Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

5 files changed, 2927 insertions, 0 deletions

diff --git a/vendor/tiff/src/decoder/ifd.rs b/vendor/tiff/src/decoder/ifd.rs
new file mode 100644
index 0000000..b05513d
--- /dev/null
+++ b/vendor/tiff/src/decoder/ifd.rs
@@ -0,0 +1,670 @@
+//! Function for reading TIFF tags
+
+use std::collections::HashMap;
+use std::convert::{TryFrom, TryInto};
+use std::io::{self, Read, Seek};
+use std::mem;
+use std::str;
+
+use super::stream::{ByteOrder, EndianReader, SmartReader};
+use crate::tags::{Tag, Type};
+use crate::{TiffError, TiffFormatError, TiffResult};
+
+use self::Value::{
+    Ascii, Byte, Double, Float, Ifd, IfdBig, List, Rational, RationalBig, SRational, SRationalBig,
+    Short, Signed, SignedBig, Unsigned, UnsignedBig,
+};
+
+#[allow(unused_qualifications)]
+#[derive(Debug, Clone, PartialEq)]
+#[non_exhaustive]
+pub enum Value {
+    Byte(u8),
+    Short(u16),
+    Signed(i32),
+    SignedBig(i64),
+    Unsigned(u32),
+    UnsignedBig(u64),
+    Float(f32),
+    Double(f64),
+    List(Vec<Value>),
+    Rational(u32, u32),
+    RationalBig(u64, u64),
+    SRational(i32, i32),
+    SRationalBig(i64, i64),
+    Ascii(String),
+    Ifd(u32),
+    IfdBig(u64),
+}
+
+impl Value {
+    pub fn into_u8(self) -> TiffResult<u8> {
+        match self {
+            Byte(val) => Ok(val),
+            val => Err(TiffError::FormatError(TiffFormatError::ByteExpected(val))),
+        }
+    }
+
+    pub fn into_u16(self) -> TiffResult<u16> {
+        match self {
+            Short(val) => Ok(val),
+            Unsigned(val) => Ok(u16::try_from(val)?),
+            UnsignedBig(val) => Ok(u16::try_from(val)?),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u32(self) -> TiffResult<u32> {
+        match self {
+            Short(val) => Ok(val.into()),
+            Unsigned(val) => Ok(val),
+            UnsignedBig(val) => Ok(u32::try_from(val)?),
+            Ifd(val) => Ok(val),
+            IfdBig(val) => Ok(u32::try_from(val)?),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_i32(self) -> TiffResult<i32> {
+        match self {
+            Signed(val) => Ok(val),
+            SignedBig(val) => Ok(i32::try_from(val)?),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u64(self) -> TiffResult<u64> {
+        match self {
+            Short(val) => Ok(val.into()),
+            Unsigned(val) => Ok(val.into()),
+            UnsignedBig(val) => Ok(val),
+            Ifd(val) => Ok(val.into()),
+            IfdBig(val) => Ok(val),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_i64(self) -> TiffResult<i64> {
+        match self {
+            Signed(val) => Ok(val.into()),
+            SignedBig(val) => Ok(val),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_f32(self) -> TiffResult<f32> {
+        match self {
+            Float(val) => Ok(val),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_f64(self) -> TiffResult<f64> {
+        match self {
+            Double(val) => Ok(val),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_string(self) -> TiffResult<String> {
+        match self {
+            Ascii(val) => Ok(val),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u32_vec(self) -> TiffResult<Vec<u32>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_u32()?)
+                }
+                Ok(new_vec)
+            }
+            Unsigned(val) => Ok(vec![val]),
+            UnsignedBig(val) => Ok(vec![u32::try_from(val)?]),
+            Rational(numerator, denominator) => Ok(vec![numerator, denominator]),
+            RationalBig(numerator, denominator) => {
+                Ok(vec![u32::try_from(numerator)?, u32::try_from(denominator)?])
+            }
+            Ifd(val) => Ok(vec![val]),
+            IfdBig(val) => Ok(vec![u32::try_from(val)?]),
+            Ascii(val) => Ok(val.chars().map(u32::from).collect()),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u8_vec(self) -> TiffResult<Vec<u8>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_u8()?)
+                }
+                Ok(new_vec)
+            }
+            Byte(val) => Ok(vec![val]),
+
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u16_vec(self) -> TiffResult<Vec<u16>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_u16()?)
+                }
+                Ok(new_vec)
+            }
+            Short(val) => Ok(vec![val]),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_i32_vec(self) -> TiffResult<Vec<i32>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    match v {
+                        SRational(numerator, denominator) => {
+                            new_vec.push(numerator);
+                            new_vec.push(denominator);
+                        }
+                        SRationalBig(numerator, denominator) => {
+                            new_vec.push(i32::try_from(numerator)?);
+                            new_vec.push(i32::try_from(denominator)?);
+                        }
+                        _ => new_vec.push(v.into_i32()?),
+                    }
+                }
+                Ok(new_vec)
+            }
+            Signed(val) => Ok(vec![val]),
+            SignedBig(val) => Ok(vec![i32::try_from(val)?]),
+            SRational(numerator, denominator) => Ok(vec![numerator, denominator]),
+            SRationalBig(numerator, denominator) => {
+                Ok(vec![i32::try_from(numerator)?, i32::try_from(denominator)?])
+            }
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_f32_vec(self) -> TiffResult<Vec<f32>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_f32()?)
+                }
+                Ok(new_vec)
+            }
+            Float(val) => Ok(vec![val]),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_f64_vec(self) -> TiffResult<Vec<f64>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_f64()?)
+                }
+                Ok(new_vec)
+            }
+            Double(val) => Ok(vec![val]),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_u64_vec(self) -> TiffResult<Vec<u64>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    new_vec.push(v.into_u64()?)
+                }
+                Ok(new_vec)
+            }
+            Unsigned(val) => Ok(vec![val.into()]),
+            UnsignedBig(val) => Ok(vec![val]),
+            Rational(numerator, denominator) => Ok(vec![numerator.into(), denominator.into()]),
+            RationalBig(numerator, denominator) => Ok(vec![numerator, denominator]),
+            Ifd(val) => Ok(vec![val.into()]),
+            IfdBig(val) => Ok(vec![val]),
+            Ascii(val) => Ok(val.chars().map(u32::from).map(u64::from).collect()),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::UnsignedIntegerExpected(val),
+            )),
+        }
+    }
+
+    pub fn into_i64_vec(self) -> TiffResult<Vec<i64>> {
+        match self {
+            List(vec) => {
+                let mut new_vec = Vec::with_capacity(vec.len());
+                for v in vec {
+                    match v {
+                        SRational(numerator, denominator) => {
+                            new_vec.push(numerator.into());
+                            new_vec.push(denominator.into());
+                        }
+                        SRationalBig(numerator, denominator) => {
+                            new_vec.push(numerator);
+                            new_vec.push(denominator);
+                        }
+                        _ => new_vec.push(v.into_i64()?),
+                    }
+                }
+                Ok(new_vec)
+            }
+            Signed(val) => Ok(vec![val.into()]),
+            SignedBig(val) => Ok(vec![val]),
+            SRational(numerator, denominator) => Ok(vec![numerator.into(), denominator.into()]),
+            SRationalBig(numerator, denominator) => Ok(vec![numerator, denominator]),
+            val => Err(TiffError::FormatError(
+                TiffFormatError::SignedIntegerExpected(val),
+            )),
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct Entry {
+    type_: Type,
+    count: u64,
+    offset: [u8; 8],
+}
+
+impl ::std::fmt::Debug for Entry {
+    fn fmt(&self, fmt: &mut ::std::fmt::Formatter) -> Result<(), ::std::fmt::Error> {
+        fmt.write_str(&format!(
+            "Entry {{ type_: {:?}, count: {:?}, offset: {:?} }}",
+            self.type_, self.count, &self.offset
+        ))
+    }
+}
+
+impl Entry {
+    pub fn new(type_: Type, count: u32, offset: [u8; 4]) -> Entry {
+        let mut offset = offset.to_vec();
+        offset.append(&mut vec![0; 4]);
+        Entry::new_u64(type_, count.into(), offset[..].try_into().unwrap())
+    }
+
+    pub fn new_u64(type_: Type, count: u64, offset: [u8; 8]) -> Entry {
+        Entry {
+            type_,
+            count,
+            offset,
+        }
+    }
+
+    /// Returns a mem_reader for the offset/value field
+    fn r(&self, byte_order: ByteOrder) -> SmartReader<io::Cursor<Vec<u8>>> {
+        SmartReader::wrap(io::Cursor::new(self.offset.to_vec()), byte_order)
+    }
+
+    pub fn val<R: Read + Seek>(
+        &self,
+        limits: &super::Limits,
+        bigtiff: bool,
+        reader: &mut SmartReader<R>,
+    ) -> TiffResult<Value> {
+        // Case 1: there are no values so we can return immediately.
+        if self.count == 0 {
+            return Ok(List(Vec::new()));
+        }
+
+        let bo = reader.byte_order();
+
+        let tag_size = match self.type_ {
+            Type::BYTE | Type::SBYTE | Type::ASCII | Type::UNDEFINED => 1,
+            Type::SHORT | Type::SSHORT => 2,
+            Type::LONG | Type::SLONG | Type::FLOAT | Type::IFD => 4,
+            Type::LONG8
+            | Type::SLONG8
+            | Type::DOUBLE
+            | Type::RATIONAL
+            | Type::SRATIONAL
+            | Type::IFD8 => 8,
+        };
+
+        let value_bytes = match self.count.checked_mul(tag_size) {
+            Some(n) => n,
+            None => {
+                return Err(TiffError::LimitsExceeded);
+            }
+        };
+
+        // Case 2: there is one value.
+        if self.count == 1 {
+            // 2a: the value is 5-8 bytes and we're in BigTiff mode.
+            if bigtiff && value_bytes > 4 && value_bytes <= 8 {
+                return Ok(match self.type_ {
+                    Type::LONG8 => UnsignedBig(self.r(bo).read_u64()?),
+                    Type::SLONG8 => SignedBig(self.r(bo).read_i64()?),
+                    Type::DOUBLE => Double(self.r(bo).read_f64()?),
+                    Type::RATIONAL => {
+                        let mut r = self.r(bo);
+                        Rational(r.read_u32()?, r.read_u32()?)
+                    }
+                    Type::SRATIONAL => {
+                        let mut r = self.r(bo);
+                        SRational(r.read_i32()?, r.read_i32()?)
+                    }
+                    Type::IFD8 => IfdBig(self.r(bo).read_u64()?),
+                    Type::BYTE
+                    | Type::SBYTE
+                    | Type::ASCII
+                    | Type::UNDEFINED
+                    | Type::SHORT
+                    | Type::SSHORT
+                    | Type::LONG
+                    | Type::SLONG
+                    | Type::FLOAT
+                    | Type::IFD => unreachable!(),
+                });
+            }
+
+            // 2b: the value is at most 4 bytes or doesn't fit in the offset field.
+            return Ok(match self.type_ {
+                Type::BYTE => Unsigned(u32::from(self.offset[0])),
+                Type::SBYTE => Signed(i32::from(self.offset[0] as i8)),
+                Type::UNDEFINED => Byte(self.offset[0]),
+                Type::SHORT => Unsigned(u32::from(self.r(bo).read_u16()?)),
+                Type::SSHORT => Signed(i32::from(self.r(bo).read_i16()?)),
+                Type::LONG => Unsigned(self.r(bo).read_u32()?),
+                Type::SLONG => Signed(self.r(bo).read_i32()?),
+                Type::FLOAT => Float(self.r(bo).read_f32()?),
+                Type::ASCII => {
+                    if self.offset[0] == 0 {
+                        Ascii("".to_string())
+                    } else {
+                        return Err(TiffError::FormatError(TiffFormatError::InvalidTag));
+                    }
+                }
+                Type::LONG8 => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    UnsignedBig(reader.read_u64()?)
+                }
+                Type::SLONG8 => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    SignedBig(reader.read_i64()?)
+                }
+                Type::DOUBLE => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    Double(reader.read_f64()?)
+                }
+                Type::RATIONAL => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    Rational(reader.read_u32()?, reader.read_u32()?)
+                }
+                Type::SRATIONAL => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    SRational(reader.read_i32()?, reader.read_i32()?)
+                }
+                Type::IFD => Ifd(self.r(bo).read_u32()?),
+                Type::IFD8 => {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?;
+                    IfdBig(reader.read_u64()?)
+                }
+            });
+        }
+
+        // Case 3: There is more than one value, but it fits in the offset field.
+        if value_bytes <= 4 || bigtiff && value_bytes <= 8 {
+            match self.type_ {
+                Type::BYTE => return offset_to_bytes(self.count as usize, self),
+                Type::SBYTE => return offset_to_sbytes(self.count as usize, self),
+                Type::ASCII => {
+                    let mut buf = vec![0; self.count as usize];
+                    self.r(bo).read_exact(&mut buf)?;
+                    if buf.is_ascii() && buf.ends_with(&[0]) {
+                        let v = str::from_utf8(&buf)?;
+                        let v = v.trim_matches(char::from(0));
+                        return Ok(Ascii(v.into()));
+                    } else {
+                        return Err(TiffError::FormatError(TiffFormatError::InvalidTag));
+                    }
+                }
+                Type::UNDEFINED => {
+                    return Ok(List(
+                        self.offset[0..self.count as usize]
+                            .iter()
+                            .map(|&b| Byte(b))
+                            .collect(),
+                    ));
+                }
+                Type::SHORT => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Short(r.read_u16()?));
+                    }
+                    return Ok(List(v));
+                }
+                Type::SSHORT => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Signed(i32::from(r.read_i16()?)));
+                    }
+                    return Ok(List(v));
+                }
+                Type::LONG => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Unsigned(r.read_u32()?));
+                    }
+                    return Ok(List(v));
+                }
+                Type::SLONG => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Signed(r.read_i32()?));
+                    }
+                    return Ok(List(v));
+                }
+                Type::FLOAT => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Float(r.read_f32()?));
+                    }
+                    return Ok(List(v));
+                }
+                Type::IFD => {
+                    let mut r = self.r(bo);
+                    let mut v = Vec::new();
+                    for _ in 0..self.count {
+                        v.push(Ifd(r.read_u32()?));
+                    }
+                    return Ok(List(v));
+                }
+                Type::LONG8
+                | Type::SLONG8
+                | Type::RATIONAL
+                | Type::SRATIONAL
+                | Type::DOUBLE
+                | Type::IFD8 => {
+                    unreachable!()
+                }
+            }
+        }
+
+        // Case 4: there is more than one value, and it doesn't fit in the offset field.
+        match self.type_ {
+            // TODO check if this could give wrong results
+            // at a different endianess of file/computer.
+            Type::BYTE => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                let mut buf = [0; 1];
+                reader.read_exact(&mut buf)?;
+                Ok(UnsignedBig(u64::from(buf[0])))
+            }),
+            Type::SBYTE => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(SignedBig(i64::from(reader.read_i8()? as i8)))
+            }),
+            Type::SHORT => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(UnsignedBig(u64::from(reader.read_u16()?)))
+            }),
+            Type::SSHORT => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(SignedBig(i64::from(reader.read_i16()?)))
+            }),
+            Type::LONG => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(Unsigned(reader.read_u32()?))
+            }),
+            Type::SLONG => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(Signed(reader.read_i32()?))
+            }),
+            Type::FLOAT => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(Float(reader.read_f32()?))
+            }),
+            Type::DOUBLE => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(Double(reader.read_f64()?))
+            }),
+            Type::RATIONAL => {
+                self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                    Ok(Rational(reader.read_u32()?, reader.read_u32()?))
+                })
+            }
+            Type::SRATIONAL => {
+                self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                    Ok(SRational(reader.read_i32()?, reader.read_i32()?))
+                })
+            }
+            Type::LONG8 => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(UnsignedBig(reader.read_u64()?))
+            }),
+            Type::SLONG8 => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(SignedBig(reader.read_i64()?))
+            }),
+            Type::IFD => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(Ifd(reader.read_u32()?))
+            }),
+            Type::IFD8 => self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                Ok(IfdBig(reader.read_u64()?))
+            }),
+            Type::UNDEFINED => {
+                self.decode_offset(self.count, bo, bigtiff, limits, reader, |reader| {
+                    let mut buf = [0; 1];
+                    reader.read_exact(&mut buf)?;
+                    Ok(Byte(buf[0]))
+                })
+            }
+            Type::ASCII => {
+                let n = usize::try_from(self.count)?;
+                if n > limits.decoding_buffer_size {
+                    return Err(TiffError::LimitsExceeded);
+                }
+
+                if bigtiff {
+                    reader.goto_offset(self.r(bo).read_u64()?)?
+                } else {
+                    reader.goto_offset(self.r(bo).read_u32()?.into())?
+                }
+
+                let mut out = vec![0; n];
+                reader.read_exact(&mut out)?;
+                // Strings may be null-terminated, so we trim anything downstream of the null byte
+                if let Some(first) = out.iter().position(|&b| b == 0) {
+                    out.truncate(first);
+                }
+                Ok(Ascii(String::from_utf8(out)?))
+            }
+        }
+    }
+
+    #[inline]
+    fn decode_offset<R, F>(
+        &self,
+        value_count: u64,
+        bo: ByteOrder,
+        bigtiff: bool,
+        limits: &super::Limits,
+        reader: &mut SmartReader<R>,
+        decode_fn: F,
+    ) -> TiffResult<Value>
+    where
+        R: Read + Seek,
+        F: Fn(&mut SmartReader<R>) -> TiffResult<Value>,
+    {
+        let value_count = usize::try_from(value_count)?;
+        if value_count > limits.decoding_buffer_size / mem::size_of::<Value>() {
+            return Err(TiffError::LimitsExceeded);
+        }
+
+        let mut v = Vec::with_capacity(value_count);
+
+        let offset = if bigtiff {
+            self.r(bo).read_u64()?
+        } else {
+            self.r(bo).read_u32()?.into()
+        };
+        reader.goto_offset(offset)?;
+
+        for _ in 0..value_count {
+            v.push(decode_fn(reader)?)
+        }
+        Ok(List(v))
+    }
+}
+
+/// Extracts a list of BYTE tags stored in an offset
+#[inline]
+fn offset_to_bytes(n: usize, entry: &Entry) -> TiffResult<Value> {
+    Ok(List(
+        entry.offset[0..n]
+            .iter()
+            .map(|&e| Unsigned(u32::from(e)))
+            .collect(),
+    ))
+}
+
+/// Extracts a list of SBYTE tags stored in an offset
+#[inline]
+fn offset_to_sbytes(n: usize, entry: &Entry) -> TiffResult<Value> {
+    Ok(List(
+        entry.offset[0..n]
+            .iter()
+            .map(|&e| Signed(i32::from(e as i8)))
+            .collect(),
+    ))
+}
+
+/// Type representing an Image File Directory
+pub type Directory = HashMap<Tag, Entry>;
diff --git a/vendor/tiff/src/decoder/image.rs b/vendor/tiff/src/decoder/image.rs
new file mode 100644
index 0000000..c037e31
--- /dev/null
+++ b/vendor/tiff/src/decoder/image.rs
@@ -0,0 +1,601 @@
+use super::ifd::{Directory, Value};
+use super::stream::{ByteOrder, DeflateReader, JpegReader, LZWReader, PackBitsReader};
+use super::tag_reader::TagReader;
+use super::{fp_predict_f32, fp_predict_f64, DecodingBuffer, Limits};
+use super::{stream::SmartReader, ChunkType};
+use crate::tags::{CompressionMethod, PhotometricInterpretation, Predictor, SampleFormat, Tag};
+use crate::{ColorType, TiffError, TiffFormatError, TiffResult, TiffUnsupportedError, UsageError};
+use std::convert::{TryFrom, TryInto};
+use std::io::{self, Cursor, Read, Seek};
+use std::sync::Arc;
+
+#[derive(Debug)]
+pub(crate) struct StripDecodeState {
+    pub rows_per_strip: u32,
+}
+
+#[derive(Debug)]
+/// Computed values useful for tile decoding
+pub(crate) struct TileAttributes {
+    pub image_width: usize,
+    pub image_height: usize,
+
+    pub tile_width: usize,
+    pub tile_length: usize,
+}
+
+impl TileAttributes {
+    pub fn tiles_across(&self) -> usize {
+        (self.image_width + self.tile_width - 1) / self.tile_width
+    }
+    pub fn tiles_down(&self) -> usize {
+        (self.image_height + self.tile_length - 1) / self.tile_length
+    }
+    fn padding_right(&self) -> usize {
+        (self.tile_width - self.image_width % self.tile_width) % self.tile_width
+    }
+    fn padding_down(&self) -> usize {
+        (self.tile_length - self.image_height % self.tile_length) % self.tile_length
+    }
+    pub fn get_padding(&self, tile: usize) -> (usize, usize) {
+        let row = tile / self.tiles_across();
+        let column = tile % self.tiles_across();
+
+        let padding_right = if column == self.tiles_across() - 1 {
+            self.padding_right()
+        } else {
+            0
+        };
+
+        let padding_down = if row == self.tiles_down() - 1 {
+            self.padding_down()
+        } else {
+            0
+        };
+
+        (padding_right, padding_down)
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct Image {
+    pub ifd: Option<Directory>,
+    pub width: u32,
+    pub height: u32,
+    pub bits_per_sample: Vec<u8>,
+    #[allow(unused)]
+    pub samples: u8,
+    pub sample_format: Vec<SampleFormat>,
+    pub photometric_interpretation: PhotometricInterpretation,
+    pub compression_method: CompressionMethod,
+    pub predictor: Predictor,
+    pub jpeg_tables: Option<Arc<Vec<u8>>>,
+    pub chunk_type: ChunkType,
+    pub strip_decoder: Option<StripDecodeState>,
+    pub tile_attributes: Option<TileAttributes>,
+    pub chunk_offsets: Vec<u64>,
+    pub chunk_bytes: Vec<u64>,
+}
+
+impl Image {
+    pub fn from_reader<R: Read + Seek>(
+        reader: &mut SmartReader<R>,
+        ifd: Directory,
+        limits: &Limits,
+        bigtiff: bool,
+    ) -> TiffResult<Image> {
+        let mut tag_reader = TagReader {
+            reader,
+            limits,
+            ifd: &ifd,
+            bigtiff,
+        };
+
+        let width = tag_reader.require_tag(Tag::ImageWidth)?.into_u32()?;
+        let height = tag_reader.require_tag(Tag::ImageLength)?.into_u32()?;
+        if width == 0 || height == 0 {
+            return Err(TiffError::FormatError(TiffFormatError::InvalidDimensions(
+                width, height,
+            )));
+        }
+
+        let photometric_interpretation = tag_reader
+            .find_tag(Tag::PhotometricInterpretation)?
+            .map(Value::into_u16)
+            .transpose()?
+            .and_then(PhotometricInterpretation::from_u16)
+            .ok_or(TiffUnsupportedError::UnknownInterpretation)?;
+
+        // Try to parse both the compression method and the number, format, and bits of the included samples.
+        // If they are not explicitly specified, those tags are reset to their default values and not carried from previous images.
+        let compression_method = match tag_reader.find_tag(Tag::Compression)? {
+            Some(val) => CompressionMethod::from_u16(val.into_u16()?)
+                .ok_or(TiffUnsupportedError::UnknownCompressionMethod)?,
+            None => CompressionMethod::None,
+        };
+
+        let jpeg_tables = if compression_method == CompressionMethod::ModernJPEG
+            && ifd.contains_key(&Tag::JPEGTables)
+        {
+            let vec = tag_reader
+                .find_tag(Tag::JPEGTables)?
+                .unwrap()
+                .into_u8_vec()?;
+            if vec.len() < 2 {
+                return Err(TiffError::FormatError(
+                    TiffFormatError::InvalidTagValueType(Tag::JPEGTables),
+                ));
+            }
+
+            Some(Arc::new(vec))
+        } else {
+            None
+        };
+
+        let samples = tag_reader
+            .find_tag(Tag::SamplesPerPixel)?
+            .map(Value::into_u16)
+            .transpose()?
+            .unwrap_or(1)
+            .try_into()?;
+
+        let sample_format = match tag_reader.find_tag_uint_vec(Tag::SampleFormat)? {
+            Some(vals) => {
+                let sample_format: Vec<_> = vals
+                    .into_iter()
+                    .map(SampleFormat::from_u16_exhaustive)
+                    .collect();
+
+                // TODO: for now, only homogenous formats across samples are supported.
+                if !sample_format.windows(2).all(|s| s[0] == s[1]) {
+                    return Err(TiffUnsupportedError::UnsupportedSampleFormat(sample_format).into());
+                }
+
+                sample_format
+            }
+            None => vec![SampleFormat::Uint],
+        };
+
+        let bits_per_sample = match samples {
+            1 | 3 | 4 => tag_reader
+                .find_tag_uint_vec(Tag::BitsPerSample)?
+                .unwrap_or_else(|| vec![1]),
+            _ => return Err(TiffUnsupportedError::UnsupportedSampleDepth(samples).into()),
+        };
+
+        let predictor = tag_reader
+            .find_tag(Tag::Predictor)?
+            .map(Value::into_u16)
+            .transpose()?
+            .map(|p| {
+                Predictor::from_u16(p)
+                    .ok_or(TiffError::FormatError(TiffFormatError::UnknownPredictor(p)))
+            })
+            .transpose()?
+            .unwrap_or(Predictor::None);
+
+        let chunk_type;
+        let chunk_offsets;
+        let chunk_bytes;
+        let strip_decoder;
+        let tile_attributes;
+        match (
+            ifd.contains_key(&Tag::StripByteCounts),
+            ifd.contains_key(&Tag::StripOffsets),
+            ifd.contains_key(&Tag::TileByteCounts),
+            ifd.contains_key(&Tag::TileOffsets),
+        ) {
+            (true, true, false, false) => {
+                chunk_type = ChunkType::Strip;
+
+                chunk_offsets = tag_reader
+                    .find_tag(Tag::StripOffsets)?
+                    .unwrap()
+                    .into_u64_vec()?;
+                chunk_bytes = tag_reader
+                    .find_tag(Tag::StripByteCounts)?
+                    .unwrap()
+                    .into_u64_vec()?;
+                let rows_per_strip = tag_reader
+                    .find_tag(Tag::RowsPerStrip)?
+                    .map(Value::into_u32)
+                    .transpose()?
+                    .unwrap_or(height);
+                strip_decoder = Some(StripDecodeState { rows_per_strip });
+                tile_attributes = None;
+
+                if chunk_offsets.len() != chunk_bytes.len()
+                    || rows_per_strip == 0
+                    || u32::try_from(chunk_offsets.len())?
+                        != height.saturating_sub(1) / rows_per_strip + 1
+                {
+                    return Err(TiffError::FormatError(
+                        TiffFormatError::InconsistentSizesEncountered,
+                    ));
+                }
+            }
+            (false, false, true, true) => {
+                chunk_type = ChunkType::Tile;
+
+                let tile_width =
+                    usize::try_from(tag_reader.require_tag(Tag::TileWidth)?.into_u32()?)?;
+                let tile_length =
+                    usize::try_from(tag_reader.require_tag(Tag::TileLength)?.into_u32()?)?;
+
+                if tile_width == 0 {
+                    return Err(TiffFormatError::InvalidTagValueType(Tag::TileWidth).into());
+                } else if tile_length == 0 {
+                    return Err(TiffFormatError::InvalidTagValueType(Tag::TileLength).into());
+                }
+
+                strip_decoder = None;
+                tile_attributes = Some(TileAttributes {
+                    image_width: usize::try_from(width)?,
+                    image_height: usize::try_from(height)?,
+                    tile_width,
+                    tile_length,
+                });
+                chunk_offsets = tag_reader
+                    .find_tag(Tag::TileOffsets)?
+                    .unwrap()
+                    .into_u64_vec()?;
+                chunk_bytes = tag_reader
+                    .find_tag(Tag::TileByteCounts)?
+                    .unwrap()
+                    .into_u64_vec()?;
+
+                let tile = tile_attributes.as_ref().unwrap();
+                if chunk_offsets.len() != chunk_bytes.len()
+                    || chunk_offsets.len() != tile.tiles_down() * tile.tiles_across()
+                {
+                    return Err(TiffError::FormatError(
+                        TiffFormatError::InconsistentSizesEncountered,
+                    ));
+                }
+            }
+            (_, _, _, _) => {
+                return Err(TiffError::FormatError(
+                    TiffFormatError::StripTileTagConflict,
+                ))
+            }
+        };
+
+        Ok(Image {
+            ifd: Some(ifd),
+            width,
+            height,
+            bits_per_sample,
+            samples,
+            sample_format,
+            photometric_interpretation,
+            compression_method,
+            jpeg_tables,
+            predictor,
+            chunk_type,
+            strip_decoder,
+            tile_attributes,
+            chunk_offsets,
+            chunk_bytes,
+        })
+    }
+
+    pub(crate) fn colortype(&self) -> TiffResult<ColorType> {
+        match self.photometric_interpretation {
+            PhotometricInterpretation::RGB => match self.bits_per_sample[..] {
+                [r, g, b] if [r, r] == [g, b] => Ok(ColorType::RGB(r)),
+                [r, g, b, a] if [r, r, r] == [g, b, a] => Ok(ColorType::RGBA(r)),
+                // FIXME: We should _ignore_ other components. In particular:
+                // > Beware of extra components. Some TIFF files may have more components per pixel
+                // than you think. A Baseline TIFF reader must skip over them gracefully,using the
+                // values of the SamplesPerPixel and BitsPerSample fields.
+                // > -- TIFF 6.0 Specification, Section 7, Additional Baseline requirements.
+                _ => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::InterpretationWithBits(
+                        self.photometric_interpretation,
+                        self.bits_per_sample.clone(),
+                    ),
+                )),
+            },
+            PhotometricInterpretation::CMYK => match self.bits_per_sample[..] {
+                [c, m, y, k] if [c, c, c] == [m, y, k] => Ok(ColorType::CMYK(c)),
+                _ => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::InterpretationWithBits(
+                        self.photometric_interpretation,
+                        self.bits_per_sample.clone(),
+                    ),
+                )),
+            },
+            PhotometricInterpretation::YCbCr => match self.bits_per_sample[..] {
+                [y, cb, cr] if [y, y] == [cb, cr] => Ok(ColorType::YCbCr(y)),
+                _ => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::InterpretationWithBits(
+                        self.photometric_interpretation,
+                        self.bits_per_sample.clone(),
+                    ),
+                )),
+            },
+            PhotometricInterpretation::BlackIsZero | PhotometricInterpretation::WhiteIsZero
+                if self.bits_per_sample.len() == 1 =>
+            {
+                Ok(ColorType::Gray(self.bits_per_sample[0]))
+            }
+
+            // TODO: this is bad we should not fail at this point
+            _ => Err(TiffError::UnsupportedError(
+                TiffUnsupportedError::InterpretationWithBits(
+                    self.photometric_interpretation,
+                    self.bits_per_sample.clone(),
+                ),
+            )),
+        }
+    }
+
+    fn create_reader<'r, R: 'r + Read>(
+        reader: R,
+        photometric_interpretation: PhotometricInterpretation,
+        compression_method: CompressionMethod,
+        compressed_length: u64,
+        jpeg_tables: Option<Arc<Vec<u8>>>,
+    ) -> TiffResult<Box<dyn Read + 'r>> {
+        Ok(match compression_method {
+            CompressionMethod::None => Box::new(reader),
+            CompressionMethod::LZW => {
+                Box::new(LZWReader::new(reader, usize::try_from(compressed_length)?))
+            }
+            CompressionMethod::PackBits => Box::new(PackBitsReader::new(reader, compressed_length)),
+            CompressionMethod::Deflate | CompressionMethod::OldDeflate => {
+                Box::new(DeflateReader::new(reader))
+            }
+            CompressionMethod::ModernJPEG => {
+                if jpeg_tables.is_some() && compressed_length < 2 {
+                    return Err(TiffError::FormatError(
+                        TiffFormatError::InvalidTagValueType(Tag::JPEGTables),
+                    ));
+                }
+
+                let jpeg_reader = JpegReader::new(reader, compressed_length, jpeg_tables)?;
+                let mut decoder = jpeg::Decoder::new(jpeg_reader);
+
+                match photometric_interpretation {
+                    PhotometricInterpretation::RGB => {
+                        decoder.set_color_transform(jpeg::ColorTransform::RGB)
+                    }
+                    PhotometricInterpretation::WhiteIsZero => {
+                        decoder.set_color_transform(jpeg::ColorTransform::None)
+                    }
+                    PhotometricInterpretation::BlackIsZero => {
+                        decoder.set_color_transform(jpeg::ColorTransform::None)
+                    }
+                    PhotometricInterpretation::TransparencyMask => {
+                        decoder.set_color_transform(jpeg::ColorTransform::None)
+                    }
+                    PhotometricInterpretation::CMYK => {
+                        decoder.set_color_transform(jpeg::ColorTransform::CMYK)
+                    }
+                    PhotometricInterpretation::YCbCr => {
+                        decoder.set_color_transform(jpeg::ColorTransform::YCbCr)
+                    }
+                    photometric_interpretation => {
+                        return Err(TiffError::UnsupportedError(
+                            TiffUnsupportedError::UnsupportedInterpretation(
+                                photometric_interpretation,
+                            ),
+                        ));
+                    }
+                }
+
+                let data = decoder.decode()?;
+
+                Box::new(Cursor::new(data))
+            }
+            method => {
+                return Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::UnsupportedCompressionMethod(method),
+                ))
+            }
+        })
+    }
+
+    pub(crate) fn chunk_file_range(&self, chunk: u32) -> TiffResult<(u64, u64)> {
+        let file_offset = self
+            .chunk_offsets
+            .get(chunk as usize)
+            .ok_or(TiffError::FormatError(
+                TiffFormatError::InconsistentSizesEncountered,
+            ))?;
+
+        let compressed_bytes =
+            self.chunk_bytes
+                .get(chunk as usize)
+                .ok_or(TiffError::FormatError(
+                    TiffFormatError::InconsistentSizesEncountered,
+                ))?;
+
+        Ok((*file_offset, *compressed_bytes))
+    }
+
+    pub(crate) fn chunk_dimensions(&self) -> TiffResult<(u32, u32)> {
+        match self.chunk_type {
+            ChunkType::Strip => {
+                let strip_attrs = self.strip_decoder.as_ref().unwrap();
+                Ok((self.width, strip_attrs.rows_per_strip))
+            }
+            ChunkType::Tile => {
+                let tile_attrs = self.tile_attributes.as_ref().unwrap();
+                Ok((
+                    u32::try_from(tile_attrs.tile_width)?,
+                    u32::try_from(tile_attrs.tile_length)?,
+                ))
+            }
+        }
+    }
+
+    pub(crate) fn chunk_data_dimensions(&self, chunk_index: u32) -> TiffResult<(u32, u32)> {
+        let dims = self.chunk_dimensions()?;
+
+        match self.chunk_type {
+            ChunkType::Strip => {
+                let strip_height_without_padding = chunk_index
+                    .checked_mul(dims.1)
+                    .and_then(|x| self.height.checked_sub(x))
+                    .ok_or(TiffError::UsageError(UsageError::InvalidChunkIndex(
+                        chunk_index,
+                    )))?;
+
+                // Ignore potential vertical padding on the bottommost strip
+                let strip_height = dims.1.min(strip_height_without_padding);
+
+                Ok((dims.0, strip_height))
+            }
+            ChunkType::Tile => {
+                let tile_attrs = self.tile_attributes.as_ref().unwrap();
+                let (padding_right, padding_down) = tile_attrs.get_padding(chunk_index as usize);
+
+                let tile_width = tile_attrs.tile_width - padding_right;
+                let tile_length = tile_attrs.tile_length - padding_down;
+
+                Ok((u32::try_from(tile_width)?, u32::try_from(tile_length)?))
+            }
+        }
+    }
+
+    pub(crate) fn expand_chunk(
+        &self,
+        reader: impl Read,
+        mut buffer: DecodingBuffer,
+        output_width: usize,
+        byte_order: ByteOrder,
+        chunk_index: u32,
+    ) -> TiffResult<()> {
+        // Validate that the provided buffer is of the expected type.
+        let color_type = self.colortype()?;
+        match (color_type, &buffer) {
+            (ColorType::RGB(n), _)
+            | (ColorType::RGBA(n), _)
+            | (ColorType::CMYK(n), _)
+            | (ColorType::YCbCr(n), _)
+            | (ColorType::Gray(n), _)
+                if usize::from(n) == buffer.byte_len() * 8 => {}
+            (ColorType::Gray(n), DecodingBuffer::U8(_)) if n < 8 => match self.predictor {
+                Predictor::None => {}
+                Predictor::Horizontal => {
+                    return Err(TiffError::UnsupportedError(
+                        TiffUnsupportedError::HorizontalPredictor(color_type),
+                    ))
+                }
+                Predictor::FloatingPoint => {
+                    return Err(TiffError::UnsupportedError(
+                        TiffUnsupportedError::FloatingPointPredictor(color_type),
+                    ));
+                }
+            },
+            (type_, _) => {
+                return Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::UnsupportedColorType(type_),
+                ))
+            }
+        }
+
+        // Validate that the predictor is supported for the sample type.
+        match (self.predictor, &buffer) {
+            (Predictor::Horizontal, DecodingBuffer::F32(_))
+            | (Predictor::Horizontal, DecodingBuffer::F64(_)) => {
+                return Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::HorizontalPredictor(color_type),
+                ));
+            }
+            (Predictor::FloatingPoint, DecodingBuffer::F32(_))
+            | (Predictor::FloatingPoint, DecodingBuffer::F64(_)) => {}
+            (Predictor::FloatingPoint, _) => {
+                return Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::FloatingPointPredictor(color_type),
+                ));
+            }
+            _ => {}
+        }
+
+        let compressed_bytes =
+            self.chunk_bytes
+                .get(chunk_index as usize)
+                .ok_or(TiffError::FormatError(
+                    TiffFormatError::InconsistentSizesEncountered,
+                ))?;
+
+        let byte_len = buffer.byte_len();
+        let compression_method = self.compression_method;
+        let photometric_interpretation = self.photometric_interpretation;
+        let predictor = self.predictor;
+        let samples = self.bits_per_sample.len();
+
+        let chunk_dims = self.chunk_dimensions()?;
+        let data_dims = self.chunk_data_dimensions(chunk_index)?;
+
+        let padding_right = chunk_dims.0 - data_dims.0;
+
+        let jpeg_tables = self.jpeg_tables.clone();
+        let mut reader = Self::create_reader(
+            reader,
+            photometric_interpretation,
+            compression_method,
+            *compressed_bytes,
+            jpeg_tables,
+        )?;
+
+        if output_width == data_dims.0 as usize && padding_right == 0 {
+            let total_samples = data_dims.0 as usize * data_dims.1 as usize * samples;
+            let tile = &mut buffer.as_bytes_mut()[..total_samples * byte_len];
+            reader.read_exact(tile)?;
+
+            for row in 0..data_dims.1 as usize {
+                let row_start = row as usize * output_width as usize * samples;
+                let row_end = (row + 1) * output_width as usize * samples;
+                let row = buffer.subrange(row_start..row_end);
+                super::fix_endianness_and_predict(row, samples, byte_order, predictor);
+            }
+            if photometric_interpretation == PhotometricInterpretation::WhiteIsZero {
+                super::invert_colors(&mut buffer.subrange(0..total_samples), color_type);
+            }
+        } else if padding_right > 0 && self.predictor == Predictor::FloatingPoint {
+            // The floating point predictor shuffles the padding bytes into the encoded output, so
+            // this case is handled specially when needed.
+            let mut encoded = vec![0u8; chunk_dims.0 as usize * samples * byte_len];
+
+            for row in 0..data_dims.1 as usize {
+                let row_start = row * output_width as usize * samples;
+                let row_end = row_start + data_dims.0 as usize * samples;
+
+                reader.read_exact(&mut encoded)?;
+                match buffer.subrange(row_start..row_end) {
+                    DecodingBuffer::F32(buf) => fp_predict_f32(&mut encoded, buf, samples),
+                    DecodingBuffer::F64(buf) => fp_predict_f64(&mut encoded, buf, samples),
+                    _ => unreachable!(),
+                }
+                if photometric_interpretation == PhotometricInterpretation::WhiteIsZero {
+                    super::invert_colors(&mut buffer.subrange(row_start..row_end), color_type);
+                }
+            }
+        } else {
+            for row in 0..data_dims.1 as usize {
+                let row_start = row * output_width as usize * samples;
+                let row_end = row_start + data_dims.0 as usize * samples;
+
+                let row = &mut buffer.as_bytes_mut()[(row_start * byte_len)..(row_end * byte_len)];
+                reader.read_exact(row)?;
+
+                // Skip horizontal padding
+                if padding_right > 0 {
+                    let len = u64::try_from(padding_right as usize * samples * byte_len)?;
+                    io::copy(&mut reader.by_ref().take(len), &mut io::sink())?;
+                }
+
+                let mut row = buffer.subrange(row_start..row_end);
+                super::fix_endianness_and_predict(row.copy(), samples, byte_order, predictor);
+                if photometric_interpretation == PhotometricInterpretation::WhiteIsZero {
+                    super::invert_colors(&mut row, color_type);
+                }
+            }
+        }
+
+        Ok(())
+    }
+}
diff --git a/vendor/tiff/src/decoder/mod.rs b/vendor/tiff/src/decoder/mod.rs
new file mode 100644
index 0000000..5fa1812
--- /dev/null
+++ b/vendor/tiff/src/decoder/mod.rs
@@ -0,0 +1,1176 @@
+use std::collections::{HashMap, HashSet};
+use std::convert::TryFrom;
+use std::io::{self, Read, Seek};
+use std::ops::Range;
+
+use crate::{
+    bytecast, ColorType, TiffError, TiffFormatError, TiffResult, TiffUnsupportedError, UsageError,
+};
+
+use self::ifd::Directory;
+use self::image::Image;
+use crate::tags::{
+    CompressionMethod, PhotometricInterpretation, Predictor, SampleFormat, Tag, Type,
+};
+
+use self::stream::{ByteOrder, EndianReader, SmartReader};
+
+pub mod ifd;
+mod image;
+mod stream;
+mod tag_reader;
+
+/// Result of a decoding process
+#[derive(Debug)]
+pub enum DecodingResult {
+    /// A vector of unsigned bytes
+    U8(Vec<u8>),
+    /// A vector of unsigned words
+    U16(Vec<u16>),
+    /// A vector of 32 bit unsigned ints
+    U32(Vec<u32>),
+    /// A vector of 64 bit unsigned ints
+    U64(Vec<u64>),
+    /// A vector of 32 bit IEEE floats
+    F32(Vec<f32>),
+    /// A vector of 64 bit IEEE floats
+    F64(Vec<f64>),
+    /// A vector of 8 bit signed ints
+    I8(Vec<i8>),
+    /// A vector of 16 bit signed ints
+    I16(Vec<i16>),
+    /// A vector of 32 bit signed ints
+    I32(Vec<i32>),
+    /// A vector of 64 bit signed ints
+    I64(Vec<i64>),
+}
+
+impl DecodingResult {
+    fn new_u8(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::U8(vec![0; size]))
+        }
+    }
+
+    fn new_u16(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 2 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::U16(vec![0; size]))
+        }
+    }
+
+    fn new_u32(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 4 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::U32(vec![0; size]))
+        }
+    }
+
+    fn new_u64(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 8 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::U64(vec![0; size]))
+        }
+    }
+
+    fn new_f32(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / std::mem::size_of::<f32>() {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::F32(vec![0.0; size]))
+        }
+    }
+
+    fn new_f64(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / std::mem::size_of::<f64>() {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::F64(vec![0.0; size]))
+        }
+    }
+
+    fn new_i8(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / std::mem::size_of::<i8>() {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::I8(vec![0; size]))
+        }
+    }
+
+    fn new_i16(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 2 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::I16(vec![0; size]))
+        }
+    }
+
+    fn new_i32(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 4 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::I32(vec![0; size]))
+        }
+    }
+
+    fn new_i64(size: usize, limits: &Limits) -> TiffResult<DecodingResult> {
+        if size > limits.decoding_buffer_size / 8 {
+            Err(TiffError::LimitsExceeded)
+        } else {
+            Ok(DecodingResult::I64(vec![0; size]))
+        }
+    }
+
+    pub fn as_buffer(&mut self, start: usize) -> DecodingBuffer {
+        match *self {
+            DecodingResult::U8(ref mut buf) => DecodingBuffer::U8(&mut buf[start..]),
+            DecodingResult::U16(ref mut buf) => DecodingBuffer::U16(&mut buf[start..]),
+            DecodingResult::U32(ref mut buf) => DecodingBuffer::U32(&mut buf[start..]),
+            DecodingResult::U64(ref mut buf) => DecodingBuffer::U64(&mut buf[start..]),
+            DecodingResult::F32(ref mut buf) => DecodingBuffer::F32(&mut buf[start..]),
+            DecodingResult::F64(ref mut buf) => DecodingBuffer::F64(&mut buf[start..]),
+            DecodingResult::I8(ref mut buf) => DecodingBuffer::I8(&mut buf[start..]),
+            DecodingResult::I16(ref mut buf) => DecodingBuffer::I16(&mut buf[start..]),
+            DecodingResult::I32(ref mut buf) => DecodingBuffer::I32(&mut buf[start..]),
+            DecodingResult::I64(ref mut buf) => DecodingBuffer::I64(&mut buf[start..]),
+        }
+    }
+}
+
+// A buffer for image decoding
+pub enum DecodingBuffer<'a> {
+    /// A slice of unsigned bytes
+    U8(&'a mut [u8]),
+    /// A slice of unsigned words
+    U16(&'a mut [u16]),
+    /// A slice of 32 bit unsigned ints
+    U32(&'a mut [u32]),
+    /// A slice of 64 bit unsigned ints
+    U64(&'a mut [u64]),
+    /// A slice of 32 bit IEEE floats
+    F32(&'a mut [f32]),
+    /// A slice of 64 bit IEEE floats
+    F64(&'a mut [f64]),
+    /// A slice of 8 bits signed ints
+    I8(&'a mut [i8]),
+    /// A slice of 16 bits signed ints
+    I16(&'a mut [i16]),
+    /// A slice of 32 bits signed ints
+    I32(&'a mut [i32]),
+    /// A slice of 64 bits signed ints
+    I64(&'a mut [i64]),
+}
+
+impl<'a> DecodingBuffer<'a> {
+    fn byte_len(&self) -> usize {
+        match *self {
+            DecodingBuffer::U8(_) => 1,
+            DecodingBuffer::U16(_) => 2,
+            DecodingBuffer::U32(_) => 4,
+            DecodingBuffer::U64(_) => 8,
+            DecodingBuffer::F32(_) => 4,
+            DecodingBuffer::F64(_) => 8,
+            DecodingBuffer::I8(_) => 1,
+            DecodingBuffer::I16(_) => 2,
+            DecodingBuffer::I32(_) => 4,
+            DecodingBuffer::I64(_) => 8,
+        }
+    }
+
+    fn copy<'b>(&'b mut self) -> DecodingBuffer<'b>
+    where
+        'a: 'b,
+    {
+        match *self {
+            DecodingBuffer::U8(ref mut buf) => DecodingBuffer::U8(buf),
+            DecodingBuffer::U16(ref mut buf) => DecodingBuffer::U16(buf),
+            DecodingBuffer::U32(ref mut buf) => DecodingBuffer::U32(buf),
+            DecodingBuffer::U64(ref mut buf) => DecodingBuffer::U64(buf),
+            DecodingBuffer::F32(ref mut buf) => DecodingBuffer::F32(buf),
+            DecodingBuffer::F64(ref mut buf) => DecodingBuffer::F64(buf),
+            DecodingBuffer::I8(ref mut buf) => DecodingBuffer::I8(buf),
+            DecodingBuffer::I16(ref mut buf) => DecodingBuffer::I16(buf),
+            DecodingBuffer::I32(ref mut buf) => DecodingBuffer::I32(buf),
+            DecodingBuffer::I64(ref mut buf) => DecodingBuffer::I64(buf),
+        }
+    }
+
+    fn subrange<'b>(&'b mut self, range: Range<usize>) -> DecodingBuffer<'b>
+    where
+        'a: 'b,
+    {
+        match *self {
+            DecodingBuffer::U8(ref mut buf) => DecodingBuffer::U8(&mut buf[range]),
+            DecodingBuffer::U16(ref mut buf) => DecodingBuffer::U16(&mut buf[range]),
+            DecodingBuffer::U32(ref mut buf) => DecodingBuffer::U32(&mut buf[range]),
+            DecodingBuffer::U64(ref mut buf) => DecodingBuffer::U64(&mut buf[range]),
+            DecodingBuffer::F32(ref mut buf) => DecodingBuffer::F32(&mut buf[range]),
+            DecodingBuffer::F64(ref mut buf) => DecodingBuffer::F64(&mut buf[range]),
+            DecodingBuffer::I8(ref mut buf) => DecodingBuffer::I8(&mut buf[range]),
+            DecodingBuffer::I16(ref mut buf) => DecodingBuffer::I16(&mut buf[range]),
+            DecodingBuffer::I32(ref mut buf) => DecodingBuffer::I32(&mut buf[range]),
+            DecodingBuffer::I64(ref mut buf) => DecodingBuffer::I64(&mut buf[range]),
+        }
+    }
+
+    fn as_bytes_mut(&mut self) -> &mut [u8] {
+        match self {
+            DecodingBuffer::U8(buf) => &mut *buf,
+            DecodingBuffer::I8(buf) => bytecast::i8_as_ne_mut_bytes(buf),
+            DecodingBuffer::U16(buf) => bytecast::u16_as_ne_mut_bytes(buf),
+            DecodingBuffer::I16(buf) => bytecast::i16_as_ne_mut_bytes(buf),
+            DecodingBuffer::U32(buf) => bytecast::u32_as_ne_mut_bytes(buf),
+            DecodingBuffer::I32(buf) => bytecast::i32_as_ne_mut_bytes(buf),
+            DecodingBuffer::U64(buf) => bytecast::u64_as_ne_mut_bytes(buf),
+            DecodingBuffer::I64(buf) => bytecast::i64_as_ne_mut_bytes(buf),
+            DecodingBuffer::F32(buf) => bytecast::f32_as_ne_mut_bytes(buf),
+            DecodingBuffer::F64(buf) => bytecast::f64_as_ne_mut_bytes(buf),
+        }
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq)]
+/// Chunk type of the internal representation
+pub enum ChunkType {
+    Strip,
+    Tile,
+}
+
+/// Decoding limits
+#[derive(Clone, Debug)]
+pub struct Limits {
+    /// The maximum size of any `DecodingResult` in bytes, the default is
+    /// 256MiB. If the entire image is decoded at once, then this will
+    /// be the maximum size of the image. If it is decoded one strip at a
+    /// time, this will be the maximum size of a strip.
+    pub decoding_buffer_size: usize,
+    /// The maximum size of any ifd value in bytes, the default is
+    /// 1MiB.
+    pub ifd_value_size: usize,
+    /// Maximum size for intermediate buffer which may be used to limit the amount of data read per
+    /// segment even if the entire image is decoded at once.
+    pub intermediate_buffer_size: usize,
+    /// The purpose of this is to prevent all the fields of the struct from
+    /// being public, as this would make adding new fields a major version
+    /// bump.
+    _non_exhaustive: (),
+}
+
+impl Limits {
+    /// A configuration that does not impose any limits.
+    ///
+    /// This is a good start if the caller only wants to impose selective limits, contrary to the
+    /// default limits which allows selectively disabling limits.
+    ///
+    /// Note that this configuration is likely to crash on excessively large images since,
+    /// naturally, the machine running the program does not have infinite memory.
+    pub fn unlimited() -> Limits {
+        Limits {
+            decoding_buffer_size: usize::max_value(),
+            ifd_value_size: usize::max_value(),
+            intermediate_buffer_size: usize::max_value(),
+            _non_exhaustive: (),
+        }
+    }
+}
+
+impl Default for Limits {
+    fn default() -> Limits {
+        Limits {
+            decoding_buffer_size: 256 * 1024 * 1024,
+            intermediate_buffer_size: 128 * 1024 * 1024,
+            ifd_value_size: 1024 * 1024,
+            _non_exhaustive: (),
+        }
+    }
+}
+
+/// The representation of a TIFF decoder
+///
+/// Currently does not support decoding of interlaced images
+#[derive(Debug)]
+pub struct Decoder<R>
+where
+    R: Read + Seek,
+{
+    reader: SmartReader<R>,
+    bigtiff: bool,
+    limits: Limits,
+    next_ifd: Option<u64>,
+    ifd_offsets: Vec<u64>,
+    seen_ifds: HashSet<u64>,
+    image: Image,
+}
+
+trait Wrapping {
+    fn wrapping_add(&self, other: Self) -> Self;
+}
+
+impl Wrapping for u8 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        u8::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for u16 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        u16::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for u32 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        u32::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for u64 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        u64::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for i8 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        i8::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for i16 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        i16::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for i32 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        i32::wrapping_add(*self, other)
+    }
+}
+
+impl Wrapping for i64 {
+    fn wrapping_add(&self, other: Self) -> Self {
+        i64::wrapping_add(*self, other)
+    }
+}
+
+fn rev_hpredict_nsamp<T: Copy + Wrapping>(image: &mut [T], samples: usize) {
+    for col in samples..image.len() {
+        image[col] = image[col].wrapping_add(image[col - samples]);
+    }
+}
+
+pub fn fp_predict_f32(input: &mut [u8], output: &mut [f32], samples: usize) {
+    rev_hpredict_nsamp(input, samples);
+    for i in 0..output.len() {
+        // TODO: use f32::from_be_bytes() when we can (version 1.40)
+        output[i] = f32::from_bits(u32::from_be_bytes([
+            input[input.len() / 4 * 0 + i],
+            input[input.len() / 4 * 1 + i],
+            input[input.len() / 4 * 2 + i],
+            input[input.len() / 4 * 3 + i],
+        ]));
+    }
+}
+
+pub fn fp_predict_f64(input: &mut [u8], output: &mut [f64], samples: usize) {
+    rev_hpredict_nsamp(input, samples);
+    for i in 0..output.len() {
+        // TODO: use f64::from_be_bytes() when we can (version 1.40)
+        output[i] = f64::from_bits(u64::from_be_bytes([
+            input[input.len() / 8 * 0 + i],
+            input[input.len() / 8 * 1 + i],
+            input[input.len() / 8 * 2 + i],
+            input[input.len() / 8 * 3 + i],
+            input[input.len() / 8 * 4 + i],
+            input[input.len() / 8 * 5 + i],
+            input[input.len() / 8 * 6 + i],
+            input[input.len() / 8 * 7 + i],
+        ]));
+    }
+}
+
+fn fix_endianness_and_predict(
+    mut image: DecodingBuffer,
+    samples: usize,
+    byte_order: ByteOrder,
+    predictor: Predictor,
+) {
+    match predictor {
+        Predictor::None => {
+            fix_endianness(&mut image, byte_order);
+        }
+        Predictor::Horizontal => {
+            fix_endianness(&mut image, byte_order);
+            match image {
+                DecodingBuffer::U8(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::U16(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::U32(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::U64(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::I8(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::I16(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::I32(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::I64(buf) => rev_hpredict_nsamp(buf, samples),
+                DecodingBuffer::F32(_) | DecodingBuffer::F64(_) => {
+                    unreachable!("Caller should have validated arguments. Please file a bug.")
+                }
+            }
+        }
+        Predictor::FloatingPoint => {
+            let mut buffer_copy = image.as_bytes_mut().to_vec();
+            match image {
+                DecodingBuffer::F32(buf) => fp_predict_f32(&mut buffer_copy, buf, samples),
+                DecodingBuffer::F64(buf) => fp_predict_f64(&mut buffer_copy, buf, samples),
+                _ => unreachable!("Caller should have validated arguments. Please file a bug."),
+            }
+        }
+    }
+}
+
+fn invert_colors_unsigned<T>(buffer: &mut [T], max: T)
+where
+    T: std::ops::Sub<T> + std::ops::Sub<Output = T> + Copy,
+{
+    for datum in buffer.iter_mut() {
+        *datum = max - *datum
+    }
+}
+
+fn invert_colors_fp<T>(buffer: &mut [T], max: T)
+where
+    T: std::ops::Sub<T> + std::ops::Sub<Output = T> + Copy,
+{
+    for datum in buffer.iter_mut() {
+        // FIXME: assumes [0, 1) range for floats
+        *datum = max - *datum
+    }
+}
+
+fn invert_colors(buf: &mut DecodingBuffer, color_type: ColorType) {
+    match (color_type, buf) {
+        (ColorType::Gray(64), DecodingBuffer::U64(ref mut buffer)) => {
+            invert_colors_unsigned(buffer, 0xffff_ffff_ffff_ffff);
+        }
+        (ColorType::Gray(32), DecodingBuffer::U32(ref mut buffer)) => {
+            invert_colors_unsigned(buffer, 0xffff_ffff);
+        }
+        (ColorType::Gray(16), DecodingBuffer::U16(ref mut buffer)) => {
+            invert_colors_unsigned(buffer, 0xffff);
+        }
+        (ColorType::Gray(n), DecodingBuffer::U8(ref mut buffer)) if n <= 8 => {
+            invert_colors_unsigned(buffer, 0xff);
+        }
+        (ColorType::Gray(32), DecodingBuffer::F32(ref mut buffer)) => {
+            invert_colors_fp(buffer, 1.0);
+        }
+        (ColorType::Gray(64), DecodingBuffer::F64(ref mut buffer)) => {
+            invert_colors_fp(buffer, 1.0);
+        }
+        _ => {}
+    }
+}
+
+/// Fix endianness. If `byte_order` matches the host, then conversion is a no-op.
+fn fix_endianness(buf: &mut DecodingBuffer, byte_order: ByteOrder) {
+    match byte_order {
+        ByteOrder::LittleEndian => match buf {
+            DecodingBuffer::U8(_) | DecodingBuffer::I8(_) => {}
+            DecodingBuffer::U16(b) => b.iter_mut().for_each(|v| *v = u16::from_le(*v)),
+            DecodingBuffer::I16(b) => b.iter_mut().for_each(|v| *v = i16::from_le(*v)),
+            DecodingBuffer::U32(b) => b.iter_mut().for_each(|v| *v = u32::from_le(*v)),
+            DecodingBuffer::I32(b) => b.iter_mut().for_each(|v| *v = i32::from_le(*v)),
+            DecodingBuffer::U64(b) => b.iter_mut().for_each(|v| *v = u64::from_le(*v)),
+            DecodingBuffer::I64(b) => b.iter_mut().for_each(|v| *v = i64::from_le(*v)),
+            DecodingBuffer::F32(b) => b
+                .iter_mut()
+                .for_each(|v| *v = f32::from_bits(u32::from_le(v.to_bits()))),
+            DecodingBuffer::F64(b) => b
+                .iter_mut()
+                .for_each(|v| *v = f64::from_bits(u64::from_le(v.to_bits()))),
+        },
+        ByteOrder::BigEndian => match buf {
+            DecodingBuffer::U8(_) | DecodingBuffer::I8(_) => {}
+            DecodingBuffer::U16(b) => b.iter_mut().for_each(|v| *v = u16::from_be(*v)),
+            DecodingBuffer::I16(b) => b.iter_mut().for_each(|v| *v = i16::from_be(*v)),
+            DecodingBuffer::U32(b) => b.iter_mut().for_each(|v| *v = u32::from_be(*v)),
+            DecodingBuffer::I32(b) => b.iter_mut().for_each(|v| *v = i32::from_be(*v)),
+            DecodingBuffer::U64(b) => b.iter_mut().for_each(|v| *v = u64::from_be(*v)),
+            DecodingBuffer::I64(b) => b.iter_mut().for_each(|v| *v = i64::from_be(*v)),
+            DecodingBuffer::F32(b) => b
+                .iter_mut()
+                .for_each(|v| *v = f32::from_bits(u32::from_be(v.to_bits()))),
+            DecodingBuffer::F64(b) => b
+                .iter_mut()
+                .for_each(|v| *v = f64::from_bits(u64::from_be(v.to_bits()))),
+        },
+    };
+}
+
+impl<R: Read + Seek> Decoder<R> {
+    /// Create a new decoder that decodes from the stream ```r```
+    pub fn new(mut r: R) -> TiffResult<Decoder<R>> {
+        let mut endianess = Vec::with_capacity(2);
+        (&mut r).take(2).read_to_end(&mut endianess)?;
+        let byte_order = match &*endianess {
+            b"II" => ByteOrder::LittleEndian,
+            b"MM" => ByteOrder::BigEndian,
+            _ => {
+                return Err(TiffError::FormatError(
+                    TiffFormatError::TiffSignatureNotFound,
+                ))
+            }
+        };
+        let mut reader = SmartReader::wrap(r, byte_order);
+
+        let bigtiff = match reader.read_u16()? {
+            42 => false,
+            43 => {
+                // Read bytesize of offsets (in bigtiff it's alway 8 but provide a way to move to 16 some day)
+                if reader.read_u16()? != 8 {
+                    return Err(TiffError::FormatError(
+                        TiffFormatError::TiffSignatureNotFound,
+                    ));
+                }
+                // This constant should always be 0
+                if reader.read_u16()? != 0 {
+                    return Err(TiffError::FormatError(
+                        TiffFormatError::TiffSignatureNotFound,
+                    ));
+                }
+                true
+            }
+            _ => {
+                return Err(TiffError::FormatError(
+                    TiffFormatError::TiffSignatureInvalid,
+                ))
+            }
+        };
+        let next_ifd = if bigtiff {
+            Some(reader.read_u64()?)
+        } else {
+            Some(u64::from(reader.read_u32()?))
+        };
+
+        let mut seen_ifds = HashSet::new();
+        seen_ifds.insert(*next_ifd.as_ref().unwrap());
+        let ifd_offsets = vec![*next_ifd.as_ref().unwrap()];
+
+        let mut decoder = Decoder {
+            reader,
+            bigtiff,
+            limits: Default::default(),
+            next_ifd,
+            ifd_offsets,
+            seen_ifds,
+            image: Image {
+                ifd: None,
+                width: 0,
+                height: 0,
+                bits_per_sample: vec![1],
+                samples: 1,
+                sample_format: vec![SampleFormat::Uint],
+                photometric_interpretation: PhotometricInterpretation::BlackIsZero,
+                compression_method: CompressionMethod::None,
+                jpeg_tables: None,
+                predictor: Predictor::None,
+                chunk_type: ChunkType::Strip,
+                strip_decoder: None,
+                tile_attributes: None,
+                chunk_offsets: Vec::new(),
+                chunk_bytes: Vec::new(),
+            },
+        };
+        decoder.next_image()?;
+        Ok(decoder)
+    }
+
+    pub fn with_limits(mut self, limits: Limits) -> Decoder<R> {
+        self.limits = limits;
+        self
+    }
+
+    pub fn dimensions(&mut self) -> TiffResult<(u32, u32)> {
+        Ok((self.image().width, self.image().height))
+    }
+
+    pub fn colortype(&mut self) -> TiffResult<ColorType> {
+        self.image().colortype()
+    }
+
+    fn image(&self) -> &Image {
+        &self.image
+    }
+
+    /// Loads the IFD at the specified index in the list, if one exists
+    pub fn seek_to_image(&mut self, ifd_index: usize) -> TiffResult<()> {
+        // Check whether we have seen this IFD before, if so then the index will be less than the length of the list of ifd offsets
+        if ifd_index >= self.ifd_offsets.len() {
+            // We possibly need to load in the next IFD
+            if self.next_ifd.is_none() {
+                return Err(TiffError::FormatError(
+                    TiffFormatError::ImageFileDirectoryNotFound,
+                ));
+            }
+
+            loop {
+                // Follow the list until we find the one we want, or we reach the end, whichever happens first
+                let (_ifd, next_ifd) = self.next_ifd()?;
+
+                if next_ifd.is_none() {
+                    break;
+                }
+
+                if ifd_index < self.ifd_offsets.len() {
+                    break;
+                }
+            }
+        }
+
+        // If the index is within the list of ifds then we can load the selected image/IFD
+        if let Some(ifd_offset) = self.ifd_offsets.get(ifd_index) {
+            let (ifd, _next_ifd) = Self::read_ifd(&mut self.reader, self.bigtiff, *ifd_offset)?;
+
+            self.image = Image::from_reader(&mut self.reader, ifd, &self.limits, self.bigtiff)?;
+
+            Ok(())
+        } else {
+            Err(TiffError::FormatError(
+                TiffFormatError::ImageFileDirectoryNotFound,
+            ))
+        }
+    }
+
+    fn next_ifd(&mut self) -> TiffResult<(Directory, Option<u64>)> {
+        if self.next_ifd.is_none() {
+            return Err(TiffError::FormatError(
+                TiffFormatError::ImageFileDirectoryNotFound,
+            ));
+        }
+
+        let (ifd, next_ifd) = Self::read_ifd(
+            &mut self.reader,
+            self.bigtiff,
+            self.next_ifd.take().unwrap(),
+        )?;
+
+        if let Some(next) = next_ifd {
+            if !self.seen_ifds.insert(next) {
+                return Err(TiffError::FormatError(TiffFormatError::CycleInOffsets));
+            }
+            self.next_ifd = Some(next);
+            self.ifd_offsets.push(next);
+        }
+
+        Ok((ifd, next_ifd))
+    }
+
+    /// Reads in the next image.
+    /// If there is no further image in the TIFF file a format error is returned.
+    /// To determine whether there are more images call `TIFFDecoder::more_images` instead.
+    pub fn next_image(&mut self) -> TiffResult<()> {
+        let (ifd, _next_ifd) = self.next_ifd()?;
+
+        self.image = Image::from_reader(&mut self.reader, ifd, &self.limits, self.bigtiff)?;
+        Ok(())
+    }
+
+    /// Returns `true` if there is at least one more image available.
+    pub fn more_images(&self) -> bool {
+        self.next_ifd.is_some()
+    }
+
+    /// Returns the byte_order
+    pub fn byte_order(&self) -> ByteOrder {
+        self.reader.byte_order
+    }
+
+    #[inline]
+    pub fn read_ifd_offset(&mut self) -> Result<u64, io::Error> {
+        if self.bigtiff {
+            self.read_long8()
+        } else {
+            self.read_long().map(u64::from)
+        }
+    }
+
+    /// Reads a TIFF byte value
+    #[inline]
+    pub fn read_byte(&mut self) -> Result<u8, io::Error> {
+        let mut buf = [0; 1];
+        self.reader.read_exact(&mut buf)?;
+        Ok(buf[0])
+    }
+
+    /// Reads a TIFF short value
+    #[inline]
+    pub fn read_short(&mut self) -> Result<u16, io::Error> {
+        self.reader.read_u16()
+    }
+
+    /// Reads a TIFF sshort value
+    #[inline]
+    pub fn read_sshort(&mut self) -> Result<i16, io::Error> {
+        self.reader.read_i16()
+    }
+
+    /// Reads a TIFF long value
+    #[inline]
+    pub fn read_long(&mut self) -> Result<u32, io::Error> {
+        self.reader.read_u32()
+    }
+
+    /// Reads a TIFF slong value
+    #[inline]
+    pub fn read_slong(&mut self) -> Result<i32, io::Error> {
+        self.reader.read_i32()
+    }
+
+    /// Reads a TIFF float value
+    #[inline]
+    pub fn read_float(&mut self) -> Result<f32, io::Error> {
+        self.reader.read_f32()
+    }
+
+    /// Reads a TIFF double value
+    #[inline]
+    pub fn read_double(&mut self) -> Result<f64, io::Error> {
+        self.reader.read_f64()
+    }
+
+    #[inline]
+    pub fn read_long8(&mut self) -> Result<u64, io::Error> {
+        self.reader.read_u64()
+    }
+
+    #[inline]
+    pub fn read_slong8(&mut self) -> Result<i64, io::Error> {
+        self.reader.read_i64()
+    }
+
+    /// Reads a string
+    #[inline]
+    pub fn read_string(&mut self, length: usize) -> TiffResult<String> {
+        let mut out = vec![0; length];
+        self.reader.read_exact(&mut out)?;
+        // Strings may be null-terminated, so we trim anything downstream of the null byte
+        if let Some(first) = out.iter().position(|&b| b == 0) {
+            out.truncate(first);
+        }
+        Ok(String::from_utf8(out)?)
+    }
+
+    /// Reads a TIFF IFA offset/value field
+    #[inline]
+    pub fn read_offset(&mut self) -> TiffResult<[u8; 4]> {
+        if self.bigtiff {
+            return Err(TiffError::FormatError(
+                TiffFormatError::InconsistentSizesEncountered,
+            ));
+        }
+        let mut val = [0; 4];
+        self.reader.read_exact(&mut val)?;
+        Ok(val)
+    }
+
+    /// Reads a TIFF IFA offset/value field
+    #[inline]
+    pub fn read_offset_u64(&mut self) -> Result<[u8; 8], io::Error> {
+        let mut val = [0; 8];
+        self.reader.read_exact(&mut val)?;
+        Ok(val)
+    }
+
+    /// Moves the cursor to the specified offset
+    #[inline]
+    pub fn goto_offset(&mut self, offset: u32) -> io::Result<()> {
+        self.goto_offset_u64(offset.into())
+    }
+
+    #[inline]
+    pub fn goto_offset_u64(&mut self, offset: u64) -> io::Result<()> {
+        self.reader.seek(io::SeekFrom::Start(offset)).map(|_| ())
+    }
+
+    /// Reads a IFD entry.
+    // An IFD entry has four fields:
+    //
+    // Tag   2 bytes
+    // Type  2 bytes
+    // Count 4 bytes
+    // Value 4 bytes either a pointer the value itself
+    fn read_entry(
+        reader: &mut SmartReader<R>,
+        bigtiff: bool,
+    ) -> TiffResult<Option<(Tag, ifd::Entry)>> {
+        let tag = Tag::from_u16_exhaustive(reader.read_u16()?);
+        let type_ = match Type::from_u16(reader.read_u16()?) {
+            Some(t) => t,
+            None => {
+                // Unknown type. Skip this entry according to spec.
+                reader.read_u32()?;
+                reader.read_u32()?;
+                return Ok(None);
+            }
+        };
+        let entry = if bigtiff {
+            let mut offset = [0; 8];
+
+            let count = reader.read_u64()?;
+            reader.read_exact(&mut offset)?;
+            ifd::Entry::new_u64(type_, count, offset)
+        } else {
+            let mut offset = [0; 4];
+
+            let count = reader.read_u32()?;
+            reader.read_exact(&mut offset)?;
+            ifd::Entry::new(type_, count, offset)
+        };
+        Ok(Some((tag, entry)))
+    }
+
+    /// Reads the IFD starting at the indicated location.
+    fn read_ifd(
+        reader: &mut SmartReader<R>,
+        bigtiff: bool,
+        ifd_location: u64,
+    ) -> TiffResult<(Directory, Option<u64>)> {
+        reader.goto_offset(ifd_location)?;
+
+        let mut dir: Directory = HashMap::new();
+
+        let num_tags = if bigtiff {
+            reader.read_u64()?
+        } else {
+            reader.read_u16()?.into()
+        };
+        for _ in 0..num_tags {
+            let (tag, entry) = match Self::read_entry(reader, bigtiff)? {
+                Some(val) => val,
+                None => {
+                    continue;
+                } // Unknown data type in tag, skip
+            };
+            dir.insert(tag, entry);
+        }
+
+        let next_ifd = if bigtiff {
+            reader.read_u64()?
+        } else {
+            reader.read_u32()?.into()
+        };
+
+        let next_ifd = match next_ifd {
+            0 => None,
+            _ => Some(next_ifd),
+        };
+
+        Ok((dir, next_ifd))
+    }
+
+    /// Tries to retrieve a tag.
+    /// Return `Ok(None)` if the tag is not present.
+    pub fn find_tag(&mut self, tag: Tag) -> TiffResult<Option<ifd::Value>> {
+        let entry = match self.image().ifd.as_ref().unwrap().get(&tag) {
+            None => return Ok(None),
+            Some(entry) => entry.clone(),
+        };
+
+        Ok(Some(entry.val(
+            &self.limits,
+            self.bigtiff,
+            &mut self.reader,
+        )?))
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired unsigned type.
+    pub fn find_tag_unsigned<T: TryFrom<u64>>(&mut self, tag: Tag) -> TiffResult<Option<T>> {
+        self.find_tag(tag)?
+            .map(|v| v.into_u64())
+            .transpose()?
+            .map(|value| {
+                T::try_from(value).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into())
+            })
+            .transpose()
+    }
+
+    /// Tries to retrieve a vector of all a tag's values and convert them to
+    /// the desired unsigned type.
+    pub fn find_tag_unsigned_vec<T: TryFrom<u64>>(
+        &mut self,
+        tag: Tag,
+    ) -> TiffResult<Option<Vec<T>>> {
+        self.find_tag(tag)?
+            .map(|v| v.into_u64_vec())
+            .transpose()?
+            .map(|v| {
+                v.into_iter()
+                    .map(|u| {
+                        T::try_from(u).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into())
+                    })
+                    .collect()
+            })
+            .transpose()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired unsigned type.
+    /// Returns an error if the tag is not present.
+    pub fn get_tag_unsigned<T: TryFrom<u64>>(&mut self, tag: Tag) -> TiffResult<T> {
+        self.find_tag_unsigned(tag)?
+            .ok_or_else(|| TiffFormatError::RequiredTagNotFound(tag).into())
+    }
+
+    /// Tries to retrieve a tag.
+    /// Returns an error if the tag is not present
+    pub fn get_tag(&mut self, tag: Tag) -> TiffResult<ifd::Value> {
+        match self.find_tag(tag)? {
+            Some(val) => Ok(val),
+            None => Err(TiffError::FormatError(
+                TiffFormatError::RequiredTagNotFound(tag),
+            )),
+        }
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_u32(&mut self, tag: Tag) -> TiffResult<u32> {
+        self.get_tag(tag)?.into_u32()
+    }
+    pub fn get_tag_u64(&mut self, tag: Tag) -> TiffResult<u64> {
+        self.get_tag(tag)?.into_u64()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_f32(&mut self, tag: Tag) -> TiffResult<f32> {
+        self.get_tag(tag)?.into_f32()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_f64(&mut self, tag: Tag) -> TiffResult<f64> {
+        self.get_tag(tag)?.into_f64()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_u32_vec(&mut self, tag: Tag) -> TiffResult<Vec<u32>> {
+        self.get_tag(tag)?.into_u32_vec()
+    }
+
+    pub fn get_tag_u16_vec(&mut self, tag: Tag) -> TiffResult<Vec<u16>> {
+        self.get_tag(tag)?.into_u16_vec()
+    }
+    pub fn get_tag_u64_vec(&mut self, tag: Tag) -> TiffResult<Vec<u64>> {
+        self.get_tag(tag)?.into_u64_vec()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_f32_vec(&mut self, tag: Tag) -> TiffResult<Vec<f32>> {
+        self.get_tag(tag)?.into_f32_vec()
+    }
+
+    /// Tries to retrieve a tag and convert it to the desired type.
+    pub fn get_tag_f64_vec(&mut self, tag: Tag) -> TiffResult<Vec<f64>> {
+        self.get_tag(tag)?.into_f64_vec()
+    }
+
+    /// Tries to retrieve a tag and convert it to a 8bit vector.
+    pub fn get_tag_u8_vec(&mut self, tag: Tag) -> TiffResult<Vec<u8>> {
+        self.get_tag(tag)?.into_u8_vec()
+    }
+
+    /// Tries to retrieve a tag and convert it to a ascii vector.
+    pub fn get_tag_ascii_string(&mut self, tag: Tag) -> TiffResult<String> {
+        self.get_tag(tag)?.into_string()
+    }
+
+    fn check_chunk_type(&self, expected: ChunkType) -> TiffResult<()> {
+        if expected != self.image().chunk_type {
+            return Err(TiffError::UsageError(UsageError::InvalidChunkType(
+                expected,
+                self.image().chunk_type,
+            )));
+        }
+
+        Ok(())
+    }
+
+    /// The chunk type (Strips / Tiles) of the image
+    pub fn get_chunk_type(&self) -> ChunkType {
+        self.image().chunk_type
+    }
+
+    /// Number of strips in image
+    pub fn strip_count(&mut self) -> TiffResult<u32> {
+        self.check_chunk_type(ChunkType::Strip)?;
+        let rows_per_strip = self.image().strip_decoder.as_ref().unwrap().rows_per_strip;
+
+        if rows_per_strip == 0 {
+            return Ok(0);
+        }
+
+        // rows_per_strip - 1 can never fail since we know it's at least 1
+        let height = match self.image().height.checked_add(rows_per_strip - 1) {
+            Some(h) => h,
+            None => return Err(TiffError::IntSizeError),
+        };
+
+        Ok(height / rows_per_strip)
+    }
+
+    /// Number of tiles in image
+    pub fn tile_count(&mut self) -> TiffResult<u32> {
+        self.check_chunk_type(ChunkType::Tile)?;
+        Ok(u32::try_from(self.image().chunk_offsets.len())?)
+    }
+
+    pub fn read_chunk_to_buffer(
+        &mut self,
+        mut buffer: DecodingBuffer,
+        chunk_index: u32,
+        output_width: usize,
+    ) -> TiffResult<()> {
+        let offset = self.image.chunk_file_range(chunk_index)?.0;
+        self.goto_offset_u64(offset)?;
+
+        let byte_order = self.reader.byte_order;
+
+        self.image.expand_chunk(
+            &mut self.reader,
+            buffer.copy(),
+            output_width,
+            byte_order,
+            chunk_index,
+        )?;
+
+        Ok(())
+    }
+
+    fn result_buffer(&self, width: usize, height: usize) -> TiffResult<DecodingResult> {
+        let buffer_size = match width
+            .checked_mul(height)
+            .and_then(|x| x.checked_mul(self.image().bits_per_sample.len()))
+        {
+            Some(s) => s,
+            None => return Err(TiffError::LimitsExceeded),
+        };
+
+        let max_sample_bits = self
+            .image()
+            .bits_per_sample
+            .iter()
+            .cloned()
+            .max()
+            .unwrap_or(8);
+        match self
+            .image()
+            .sample_format
+            .first()
+            .unwrap_or(&SampleFormat::Uint)
+        {
+            SampleFormat::Uint => match max_sample_bits {
+                n if n <= 8 => DecodingResult::new_u8(buffer_size, &self.limits),
+                n if n <= 16 => DecodingResult::new_u16(buffer_size, &self.limits),
+                n if n <= 32 => DecodingResult::new_u32(buffer_size, &self.limits),
+                n if n <= 64 => DecodingResult::new_u64(buffer_size, &self.limits),
+                n => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::UnsupportedBitsPerChannel(n),
+                )),
+            },
+            SampleFormat::IEEEFP => match max_sample_bits {
+                32 => DecodingResult::new_f32(buffer_size, &self.limits),
+                64 => DecodingResult::new_f64(buffer_size, &self.limits),
+                n => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::UnsupportedBitsPerChannel(n),
+                )),
+            },
+            SampleFormat::Int => match max_sample_bits {
+                n if n <= 8 => DecodingResult::new_i8(buffer_size, &self.limits),
+                n if n <= 16 => DecodingResult::new_i16(buffer_size, &self.limits),
+                n if n <= 32 => DecodingResult::new_i32(buffer_size, &self.limits),
+                n if n <= 64 => DecodingResult::new_i64(buffer_size, &self.limits),
+                n => Err(TiffError::UnsupportedError(
+                    TiffUnsupportedError::UnsupportedBitsPerChannel(n),
+                )),
+            },
+            format => {
+                Err(TiffUnsupportedError::UnsupportedSampleFormat(vec![format.clone()]).into())
+            }
+        }
+    }
+
+    /// Read the specified chunk (at index `chunk_index`) and return the binary data as a Vector.
+    pub fn read_chunk(&mut self, chunk_index: u32) -> TiffResult<DecodingResult> {
+        let data_dims = self.image().chunk_data_dimensions(chunk_index)?;
+
+        let mut result = self.result_buffer(data_dims.0 as usize, data_dims.1 as usize)?;
+
+        self.read_chunk_to_buffer(result.as_buffer(0), chunk_index, data_dims.0 as usize)?;
+
+        Ok(result)
+    }
+
+    /// Returns the default chunk size for the current image. Any given chunk in the image is at most as large as
+    /// the value returned here. For the size of the data (chunk minus padding), use `chunk_data_dimensions`.
+    pub fn chunk_dimensions(&self) -> (u32, u32) {
+        self.image().chunk_dimensions().unwrap()
+    }
+
+    /// Returns the size of the data in the chunk with the specified index. This is the default size of the chunk,
+    /// minus any padding.
+    pub fn chunk_data_dimensions(&self, chunk_index: u32) -> (u32, u32) {
+        self.image()
+            .chunk_data_dimensions(chunk_index)
+            .expect("invalid chunk_index")
+    }
+
+    /// Decodes the entire image and return it as a Vector
+    pub fn read_image(&mut self) -> TiffResult<DecodingResult> {
+        let width = self.image().width;
+        let height = self.image().height;
+        let mut result = self.result_buffer(width as usize, height as usize)?;
+        if width == 0 || height == 0 {
+            return Ok(result);
+        }
+
+        let chunk_dimensions = self.image().chunk_dimensions()?;
+        let chunk_dimensions = (
+            chunk_dimensions.0.min(width),
+            chunk_dimensions.1.min(height),
+        );
+        if chunk_dimensions.0 == 0 || chunk_dimensions.1 == 0 {
+            return Err(TiffError::FormatError(
+                TiffFormatError::InconsistentSizesEncountered,
+            ));
+        }
+
+        let samples = self.image().bits_per_sample.len();
+        if samples == 0 {
+            return Err(TiffError::FormatError(
+                TiffFormatError::InconsistentSizesEncountered,
+            ));
+        }
+
+        let chunks_across = ((width - 1) / chunk_dimensions.0 + 1) as usize;
+        let strip_samples = width as usize * chunk_dimensions.1 as usize * samples;
+
+        for chunk in 0..self.image().chunk_offsets.len() {
+            self.goto_offset_u64(self.image().chunk_offsets[chunk])?;
+
+            let x = chunk % chunks_across;
+            let y = chunk / chunks_across;
+            let buffer_offset = y * strip_samples + x * chunk_dimensions.0 as usize * samples;
+            let byte_order = self.reader.byte_order;
+            self.image.expand_chunk(
+                &mut self.reader,
+                result.as_buffer(buffer_offset).copy(),
+                width as usize,
+                byte_order,
+                chunk as u32,
+            )?;
+        }
+
+        Ok(result)
+    }
+}
diff --git a/vendor/tiff/src/decoder/stream.rs b/vendor/tiff/src/decoder/stream.rs
new file mode 100644
index 0000000..e0323c2
--- /dev/null
+++ b/vendor/tiff/src/decoder/stream.rs
@@ -0,0 +1,435 @@
+//! All IO functionality needed for TIFF decoding
+
+use std::convert::TryFrom;
+use std::io::{self, BufRead, BufReader, Read, Seek, SeekFrom, Take};
+use std::sync::Arc;
+
+/// Byte order of the TIFF file.
+#[derive(Clone, Copy, Debug)]
+pub enum ByteOrder {
+    /// little endian byte order
+    LittleEndian,
+    /// big endian byte order
+    BigEndian,
+}
+
+/// Reader that is aware of the byte order.
+pub trait EndianReader: Read {
+    /// Byte order that should be adhered to
+    fn byte_order(&self) -> ByteOrder;
+
+    /// Reads an u16
+    #[inline(always)]
+    fn read_u16(&mut self) -> Result<u16, io::Error> {
+        let mut n = [0u8; 2];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => u16::from_le_bytes(n),
+            ByteOrder::BigEndian => u16::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an i8
+    #[inline(always)]
+    fn read_i8(&mut self) -> Result<i8, io::Error> {
+        let mut n = [0u8; 1];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => i8::from_le_bytes(n),
+            ByteOrder::BigEndian => i8::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an i16
+    #[inline(always)]
+    fn read_i16(&mut self) -> Result<i16, io::Error> {
+        let mut n = [0u8; 2];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => i16::from_le_bytes(n),
+            ByteOrder::BigEndian => i16::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an u32
+    #[inline(always)]
+    fn read_u32(&mut self) -> Result<u32, io::Error> {
+        let mut n = [0u8; 4];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => u32::from_le_bytes(n),
+            ByteOrder::BigEndian => u32::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an i32
+    #[inline(always)]
+    fn read_i32(&mut self) -> Result<i32, io::Error> {
+        let mut n = [0u8; 4];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => i32::from_le_bytes(n),
+            ByteOrder::BigEndian => i32::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an u64
+    #[inline(always)]
+    fn read_u64(&mut self) -> Result<u64, io::Error> {
+        let mut n = [0u8; 8];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => u64::from_le_bytes(n),
+            ByteOrder::BigEndian => u64::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an i64
+    #[inline(always)]
+    fn read_i64(&mut self) -> Result<i64, io::Error> {
+        let mut n = [0u8; 8];
+        self.read_exact(&mut n)?;
+        Ok(match self.byte_order() {
+            ByteOrder::LittleEndian => i64::from_le_bytes(n),
+            ByteOrder::BigEndian => i64::from_be_bytes(n),
+        })
+    }
+
+    /// Reads an f32
+    #[inline(always)]
+    fn read_f32(&mut self) -> Result<f32, io::Error> {
+        let mut n = [0u8; 4];
+        self.read_exact(&mut n)?;
+        Ok(f32::from_bits(match self.byte_order() {
+            ByteOrder::LittleEndian => u32::from_le_bytes(n),
+            ByteOrder::BigEndian => u32::from_be_bytes(n),
+        }))
+    }
+
+    /// Reads an f64
+    #[inline(always)]
+    fn read_f64(&mut self) -> Result<f64, io::Error> {
+        let mut n = [0u8; 8];
+        self.read_exact(&mut n)?;
+        Ok(f64::from_bits(match self.byte_order() {
+            ByteOrder::LittleEndian => u64::from_le_bytes(n),
+            ByteOrder::BigEndian => u64::from_be_bytes(n),
+        }))
+    }
+}
+
+///
+/// # READERS
+///
+
+///
+/// ## Deflate Reader
+///
+
+pub type DeflateReader<R> = flate2::read::ZlibDecoder<R>;
+
+///
+/// ## LZW Reader
+///
+
+/// Reader that decompresses LZW streams
+pub struct LZWReader<R: Read> {
+    reader: BufReader<Take<R>>,
+    decoder: weezl::decode::Decoder,
+}
+
+impl<R: Read> LZWReader<R> {
+    /// Wraps a reader
+    pub fn new(reader: R, compressed_length: usize) -> LZWReader<R> {
+        Self {
+            reader: BufReader::with_capacity(
+                (32 * 1024).min(compressed_length),
+                reader.take(u64::try_from(compressed_length).unwrap()),
+            ),
+            decoder: weezl::decode::Decoder::with_tiff_size_switch(weezl::BitOrder::Msb, 8),
+        }
+    }
+}
+
+impl<R: Read> Read for LZWReader<R> {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        loop {
+            let result = self.decoder.decode_bytes(self.reader.fill_buf()?, buf);
+            self.reader.consume(result.consumed_in);
+
+            match result.status {
+                Ok(weezl::LzwStatus::Ok) => {
+                    if result.consumed_out == 0 {
+                        continue;
+                    } else {
+                        return Ok(result.consumed_out);
+                    }
+                }
+                Ok(weezl::LzwStatus::NoProgress) => {
+                    assert_eq!(result.consumed_in, 0);
+                    assert_eq!(result.consumed_out, 0);
+                    assert!(self.reader.buffer().is_empty());
+                    return Err(io::Error::new(
+                        io::ErrorKind::UnexpectedEof,
+                        "no lzw end code found",
+                    ));
+                }
+                Ok(weezl::LzwStatus::Done) => {
+                    return Ok(result.consumed_out);
+                }
+                Err(err) => return Err(io::Error::new(io::ErrorKind::InvalidData, err)),
+            }
+        }
+    }
+}
+
+///
+/// ## JPEG Reader (for "new-style" JPEG format (TIFF compression tag 7))
+///
+
+pub(crate) struct JpegReader {
+    jpeg_tables: Option<Arc<Vec<u8>>>,
+
+    buffer: io::Cursor<Vec<u8>>,
+
+    offset: usize,
+}
+
+impl JpegReader {
+    /// Constructs new JpegReader wrapping a SmartReader.
+    /// Because JPEG compression in TIFF allows to save quantization and/or huffman tables in one
+    /// central location, the constructor accepts this data as `jpeg_tables` here containing either
+    /// or both.
+    /// These `jpeg_tables` are simply prepended to the remaining jpeg image data.
+    /// Because these `jpeg_tables` start with a `SOI` (HEX: `0xFFD8`) or __start of image__ marker
+    /// which is also at the beginning of the remaining JPEG image data and would
+    /// confuse the JPEG renderer, one of these has to be taken off. In this case the first two
+    /// bytes of the remaining JPEG data is removed because it follows `jpeg_tables`.
+    /// Similary, `jpeg_tables` ends with a `EOI` (HEX: `0xFFD9`) or __end of image__ marker,
+    /// this has to be removed as well (last two bytes of `jpeg_tables`).
+    pub fn new<R: Read>(
+        mut reader: R,
+        length: u64,
+        jpeg_tables: Option<Arc<Vec<u8>>>,
+    ) -> io::Result<JpegReader> {
+        // Read jpeg image data
+        let mut segment = vec![0; length as usize];
+
+        reader.read_exact(&mut segment[..])?;
+
+        match jpeg_tables {
+            Some(jpeg_tables) => {
+                assert!(
+                    jpeg_tables.len() >= 2,
+                    "jpeg_tables, if given, must be at least 2 bytes long. Got {:?}",
+                    jpeg_tables
+                );
+
+                assert!(
+                    length >= 2,
+                    "if jpeg_tables is given, length must be at least 2 bytes long, got {}",
+                    length
+                );
+
+                let mut buffer = io::Cursor::new(segment);
+                // Skip the first two bytes (marker bytes)
+                buffer.seek(SeekFrom::Start(2))?;
+
+                Ok(JpegReader {
+                    buffer,
+                    jpeg_tables: Some(jpeg_tables),
+                    offset: 0,
+                })
+            }
+            None => Ok(JpegReader {
+                buffer: io::Cursor::new(segment),
+                jpeg_tables: None,
+                offset: 0,
+            }),
+        }
+    }
+}
+
+impl Read for JpegReader {
+    // #[inline]
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        let mut start = 0;
+
+        if let Some(jpeg_tables) = &self.jpeg_tables {
+            if jpeg_tables.len() - 2 > self.offset {
+                // Read (rest of) jpeg_tables to buf (without the last two bytes)
+                let size_remaining = jpeg_tables.len() - self.offset - 2;
+                let to_copy = size_remaining.min(buf.len());
+
+                buf[start..start + to_copy]
+                    .copy_from_slice(&jpeg_tables[self.offset..self.offset + to_copy]);
+
+                self.offset += to_copy;
+
+                if to_copy == buf.len() {
+                    return Ok(to_copy);
+                }
+
+                start += to_copy;
+            }
+        }
+
+        let read = self.buffer.read(&mut buf[start..])?;
+        self.offset += read;
+
+        Ok(read + start)
+    }
+}
+
+///
+/// ## PackBits Reader
+///
+
+enum PackBitsReaderState {
+    Header,
+    Literal,
+    Repeat { value: u8 },
+}
+
+/// Reader that unpacks Apple's `PackBits` format
+pub struct PackBitsReader<R: Read> {
+    reader: Take<R>,
+    state: PackBitsReaderState,
+    count: usize,
+}
+
+impl<R: Read> PackBitsReader<R> {
+    /// Wraps a reader
+    pub fn new(reader: R, length: u64) -> Self {
+        Self {
+            reader: reader.take(length),
+            state: PackBitsReaderState::Header,
+            count: 0,
+        }
+    }
+}
+
+impl<R: Read> Read for PackBitsReader<R> {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        while let PackBitsReaderState::Header = self.state {
+            if self.reader.limit() == 0 {
+                return Ok(0);
+            }
+            let mut header: [u8; 1] = [0];
+            self.reader.read_exact(&mut header)?;
+            let h = header[0] as i8;
+            if h >= -127 && h <= -1 {
+                let mut data: [u8; 1] = [0];
+                self.reader.read_exact(&mut data)?;
+                self.state = PackBitsReaderState::Repeat { value: data[0] };
+                self.count = (1 - h as isize) as usize;
+            } else if h >= 0 {
+                self.state = PackBitsReaderState::Literal;
+                self.count = h as usize + 1;
+            } else {
+                // h = -128 is a no-op.
+            }
+        }
+
+        let length = buf.len().min(self.count);
+        let actual = match self.state {
+            PackBitsReaderState::Literal => self.reader.read(&mut buf[..length])?,
+            PackBitsReaderState::Repeat { value } => {
+                for b in &mut buf[..length] {
+                    *b = value;
+                }
+
+                length
+            }
+            PackBitsReaderState::Header => unreachable!(),
+        };
+
+        self.count -= actual;
+        if self.count == 0 {
+            self.state = PackBitsReaderState::Header;
+        }
+        return Ok(actual);
+    }
+}
+
+///
+/// ## SmartReader Reader
+///
+
+/// Reader that is aware of the byte order.
+#[derive(Debug)]
+pub struct SmartReader<R>
+where
+    R: Read,
+{
+    reader: R,
+    pub byte_order: ByteOrder,
+}
+
+impl<R> SmartReader<R>
+where
+    R: Read,
+{
+    /// Wraps a reader
+    pub fn wrap(reader: R, byte_order: ByteOrder) -> SmartReader<R> {
+        SmartReader { reader, byte_order }
+    }
+    pub fn into_inner(self) -> R {
+        self.reader
+    }
+}
+impl<R: Read + Seek> SmartReader<R> {
+    pub fn goto_offset(&mut self, offset: u64) -> io::Result<()> {
+        self.seek(io::SeekFrom::Start(offset)).map(|_| ())
+    }
+}
+
+impl<R> EndianReader for SmartReader<R>
+where
+    R: Read,
+{
+    #[inline(always)]
+    fn byte_order(&self) -> ByteOrder {
+        self.byte_order
+    }
+}
+
+impl<R: Read> Read for SmartReader<R> {
+    #[inline]
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        self.reader.read(buf)
+    }
+}
+
+impl<R: Read + Seek> Seek for SmartReader<R> {
+    #[inline]
+    fn seek(&mut self, pos: io::SeekFrom) -> io::Result<u64> {
+        self.reader.seek(pos)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_packbits() {
+        let encoded = vec![
+            0xFE, 0xAA, 0x02, 0x80, 0x00, 0x2A, 0xFD, 0xAA, 0x03, 0x80, 0x00, 0x2A, 0x22, 0xF7,
+            0xAA,
+        ];
+        let encoded_len = encoded.len();
+
+        let buff = io::Cursor::new(encoded);
+        let mut decoder = PackBitsReader::new(buff, encoded_len as u64);
+
+        let mut decoded = Vec::new();
+        decoder.read_to_end(&mut decoded).unwrap();
+
+        let expected = vec![
+            0xAA, 0xAA, 0xAA, 0x80, 0x00, 0x2A, 0xAA, 0xAA, 0xAA, 0xAA, 0x80, 0x00, 0x2A, 0x22,
+            0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA,
+        ];
+        assert_eq!(decoded, expected);
+    }
+}
diff --git a/vendor/tiff/src/decoder/tag_reader.rs b/vendor/tiff/src/decoder/tag_reader.rs
new file mode 100644
index 0000000..837da40
--- /dev/null
+++ b/vendor/tiff/src/decoder/tag_reader.rs
@@ -0,0 +1,45 @@
+use std::convert::TryFrom;
+use std::io::{Read, Seek};
+
+use crate::tags::Tag;
+use crate::{TiffError, TiffFormatError, TiffResult};
+
+use super::ifd::{Directory, Value};
+use super::stream::SmartReader;
+use super::Limits;
+
+pub(crate) struct TagReader<'a, R: Read + Seek> {
+    pub reader: &'a mut SmartReader<R>,
+    pub ifd: &'a Directory,
+    pub limits: &'a Limits,
+    pub bigtiff: bool,
+}
+impl<'a, R: Read + Seek> TagReader<'a, R> {
+    pub(crate) fn find_tag(&mut self, tag: Tag) -> TiffResult<Option<Value>> {
+        Ok(match self.ifd.get(&tag) {
+            Some(entry) => Some(entry.clone().val(self.limits, self.bigtiff, self.reader)?),
+            None => None,
+        })
+    }
+    pub(crate) fn require_tag(&mut self, tag: Tag) -> TiffResult<Value> {
+        match self.find_tag(tag)? {
+            Some(val) => Ok(val),
+            None => Err(TiffError::FormatError(
+                TiffFormatError::RequiredTagNotFound(tag),
+            )),
+        }
+    }
+    pub fn find_tag_uint_vec<T: TryFrom<u64>>(&mut self, tag: Tag) -> TiffResult<Option<Vec<T>>> {
+        self.find_tag(tag)?
+            .map(|v| v.into_u64_vec())
+            .transpose()?
+            .map(|v| {
+                v.into_iter()
+                    .map(|u| {
+                        T::try_from(u).map_err(|_| TiffFormatError::InvalidTagValueType(tag).into())
+                    })
+                    .collect()
+            })
+            .transpose()
+    }
+}