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-rw-r--r--vendor/tiff/src/encoder/compression/deflate.rs83
-rw-r--r--vendor/tiff/src/encoder/compression/lzw.rs47
-rw-r--r--vendor/tiff/src/encoder/compression/mod.rs60
-rw-r--r--vendor/tiff/src/encoder/compression/packbits.rs214
-rw-r--r--vendor/tiff/src/encoder/compression/uncompressed.rs37
5 files changed, 441 insertions, 0 deletions
diff --git a/vendor/tiff/src/encoder/compression/deflate.rs b/vendor/tiff/src/encoder/compression/deflate.rs
new file mode 100644
index 0000000..5e7a261
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/deflate.rs
@@ -0,0 +1,83 @@
+use crate::{encoder::compression::*, tags::CompressionMethod};
+use flate2::{write::ZlibEncoder, Compression as FlateCompression};
+use std::io::Write;
+
+/// The Deflate algorithm used to compress image data in TIFF files.
+#[derive(Debug, Clone, Copy)]
+pub struct Deflate {
+ level: FlateCompression,
+}
+
+/// The level of compression used by the Deflate algorithm.
+/// It allows trading compression ratio for compression speed.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[non_exhaustive]
+pub enum DeflateLevel {
+ /// The fastest possible compression mode.
+ Fast = 1,
+ /// The conserative choice between speed and ratio.
+ Balanced = 6,
+ /// The best compression available with Deflate.
+ Best = 9,
+}
+
+impl Default for DeflateLevel {
+ fn default() -> Self {
+ DeflateLevel::Balanced
+ }
+}
+
+impl Deflate {
+ /// Create a new deflate compressor with a specific level of compression.
+ pub fn with_level(level: DeflateLevel) -> Self {
+ Self {
+ level: FlateCompression::new(level as u32),
+ }
+ }
+}
+
+impl Default for Deflate {
+ fn default() -> Self {
+ Self::with_level(DeflateLevel::default())
+ }
+}
+
+impl Compression for Deflate {
+ const COMPRESSION_METHOD: CompressionMethod = CompressionMethod::Deflate;
+
+ fn get_algorithm(&self) -> Compressor {
+ Compressor::Deflate(self.clone())
+ }
+}
+
+impl CompressionAlgorithm for Deflate {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ let mut encoder = ZlibEncoder::new(writer, self.level);
+ encoder.write_all(bytes)?;
+ encoder.try_finish()?;
+ Ok(encoder.total_out())
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::encoder::compression::tests::TEST_DATA;
+ use std::io::Cursor;
+
+ #[test]
+ fn test_deflate() {
+ const EXPECTED_COMPRESSED_DATA: [u8; 64] = [
+ 0x78, 0x9C, 0x15, 0xC7, 0xD1, 0x0D, 0x80, 0x20, 0x0C, 0x04, 0xD0, 0x55, 0x6E, 0x02,
+ 0xA7, 0x71, 0x81, 0xA6, 0x41, 0xDA, 0x28, 0xD4, 0xF4, 0xD0, 0xF9, 0x81, 0xE4, 0xFD,
+ 0xBC, 0xD3, 0x9C, 0x58, 0x04, 0x1C, 0xE9, 0xBD, 0xE2, 0x8A, 0x84, 0x5A, 0xD1, 0x7B,
+ 0xE7, 0x97, 0xF4, 0xF8, 0x08, 0x8D, 0xF6, 0x66, 0x21, 0x3D, 0x3A, 0xE4, 0xA9, 0x91,
+ 0x3E, 0xAC, 0xF1, 0x98, 0xB9, 0x70, 0x17, 0x13,
+ ];
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Deflate::default().write_to(&mut writer, TEST_DATA).unwrap();
+ assert_eq!(EXPECTED_COMPRESSED_DATA, compressed_data.as_slice());
+ }
+}
diff --git a/vendor/tiff/src/encoder/compression/lzw.rs b/vendor/tiff/src/encoder/compression/lzw.rs
new file mode 100644
index 0000000..0e0f2aa
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/lzw.rs
@@ -0,0 +1,47 @@
+use crate::{encoder::compression::*, tags::CompressionMethod};
+use std::io::Write;
+use weezl::encode::Encoder as LZWEncoder;
+
+/// The LZW algorithm used to compress image data in TIFF files.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub struct Lzw;
+
+impl Compression for Lzw {
+ const COMPRESSION_METHOD: CompressionMethod = CompressionMethod::LZW;
+
+ fn get_algorithm(&self) -> Compressor {
+ Compressor::Lzw(*self)
+ }
+}
+
+impl CompressionAlgorithm for Lzw {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ let mut encoder = LZWEncoder::with_tiff_size_switch(weezl::BitOrder::Msb, 8);
+ let result = encoder.into_stream(writer).encode_all(bytes);
+ let byte_count = result.bytes_written as u64;
+ result.status.map(|_| byte_count)
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::encoder::compression::tests::TEST_DATA;
+ use std::io::Cursor;
+
+ #[test]
+ fn test_lzw() {
+ const EXPECTED_COMPRESSED_DATA: [u8; 63] = [
+ 0x80, 0x15, 0x0D, 0x06, 0x93, 0x98, 0x82, 0x08, 0x20, 0x30, 0x88, 0x0E, 0x67, 0x43,
+ 0x91, 0xA4, 0xDC, 0x67, 0x10, 0x19, 0x8D, 0xE7, 0x21, 0x01, 0x8C, 0xD0, 0x65, 0x31,
+ 0x9A, 0xE1, 0xD1, 0x03, 0xB1, 0x86, 0x1A, 0x6F, 0x3A, 0xC1, 0x4C, 0x66, 0xF3, 0x69,
+ 0xC0, 0xE4, 0x65, 0x39, 0x9C, 0xCD, 0x26, 0xF3, 0x74, 0x20, 0xD8, 0x67, 0x89, 0x9A,
+ 0x4E, 0x86, 0x83, 0x69, 0xCC, 0x5D, 0x01,
+ ];
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Lzw::default().write_to(&mut writer, TEST_DATA).unwrap();
+ assert_eq!(EXPECTED_COMPRESSED_DATA, compressed_data.as_slice());
+ }
+}
diff --git a/vendor/tiff/src/encoder/compression/mod.rs b/vendor/tiff/src/encoder/compression/mod.rs
new file mode 100644
index 0000000..04baef3
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/mod.rs
@@ -0,0 +1,60 @@
+use crate::tags::CompressionMethod;
+use std::io::{self, Write};
+
+mod deflate;
+mod lzw;
+mod packbits;
+mod uncompressed;
+
+pub use self::deflate::{Deflate, DeflateLevel};
+pub use self::lzw::Lzw;
+pub use self::packbits::Packbits;
+pub use self::uncompressed::Uncompressed;
+
+/// An algorithm used for compression
+pub trait CompressionAlgorithm {
+ /// The algorithm writes data directly into the writer.
+ /// It returns the total number of bytes written.
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error>;
+}
+
+/// An algorithm used for compression with associated enums and optional configurations.
+pub trait Compression: CompressionAlgorithm {
+ /// The corresponding tag to the algorithm.
+ const COMPRESSION_METHOD: CompressionMethod;
+
+ /// Method to optain a type that can store each variant of comression algorithm.
+ fn get_algorithm(&self) -> Compressor;
+}
+
+/// An enum to store each compression algorithm.
+pub enum Compressor {
+ Uncompressed(Uncompressed),
+ Lzw(Lzw),
+ Deflate(Deflate),
+ Packbits(Packbits),
+}
+
+impl Default for Compressor {
+ /// The default compression strategy does not apply any compression.
+ fn default() -> Self {
+ Compressor::Uncompressed(Uncompressed::default())
+ }
+}
+
+impl CompressionAlgorithm for Compressor {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ match self {
+ Compressor::Uncompressed(algorithm) => algorithm.write_to(writer, bytes),
+ Compressor::Lzw(algorithm) => algorithm.write_to(writer, bytes),
+ Compressor::Deflate(algorithm) => algorithm.write_to(writer, bytes),
+ Compressor::Packbits(algorithm) => algorithm.write_to(writer, bytes),
+ }
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ pub const TEST_DATA: &'static [u8] =
+ b"This is a string for checking various compression algorithms.";
+}
diff --git a/vendor/tiff/src/encoder/compression/packbits.rs b/vendor/tiff/src/encoder/compression/packbits.rs
new file mode 100644
index 0000000..7ba3833
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/packbits.rs
@@ -0,0 +1,214 @@
+use crate::{encoder::compression::*, tags::CompressionMethod};
+use std::io::{BufWriter, Error, ErrorKind, Write};
+
+/// Compressor that uses the Packbits[^note] algorithm to compress bytes.
+///
+/// [^note]: PackBits is often ineffective on continuous tone images,
+/// including many grayscale images. In such cases, it is better
+/// to leave the image uncompressed.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub struct Packbits;
+
+impl Compression for Packbits {
+ const COMPRESSION_METHOD: CompressionMethod = CompressionMethod::PackBits;
+
+ fn get_algorithm(&self) -> Compressor {
+ Compressor::Packbits(*self)
+ }
+}
+
+impl CompressionAlgorithm for Packbits {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ // Inspired by https://github.com/skirridsystems/packbits
+
+ const MIN_REPT: u8 = 3; // Minimum run to compress between differ blocks
+ const MAX_BYTES: u8 = 128; // Maximum number of bytes that can be encoded in a header byte
+
+ // Encoding for header byte based on number of bytes represented.
+ fn encode_diff(n: u8) -> u8 {
+ n - 1
+ }
+ fn encode_rept(n: u8) -> u8 {
+ let var = 256 - (n - 1) as u16;
+ var as u8
+ }
+
+ fn write_u8<W: Write>(writer: &mut W, byte: u8) -> Result<u64, Error> {
+ writer.write(&[byte]).map(|byte_count| byte_count as u64)
+ }
+
+ let mut bufwriter = BufWriter::new(writer);
+ let mut bytes_written = 0u64; // The number of bytes written into the writer
+ let mut offset: Option<u64> = None; // The index of the first byte written into the writer
+
+ let mut src_index: usize = 0; // Index of the current byte
+ let mut src_count = bytes.len(); //The number of bytes remaining to be compressed
+
+ let mut in_run = false; // Indication whether counting of similar bytes is performed
+ let mut run_index = 0u8; // Distance into pending bytes that a run starts
+
+ let mut bytes_pending = 0u8; // Bytes looked at but not yet output
+ let mut pending_index = 0usize; // Index of the first pending byte
+
+ let mut curr_byte: u8; // Byte currently being considered
+ let mut last_byte: u8; // Previous byte
+
+ // Need at least one byte to compress
+ if src_count == 0 {
+ return Err(Error::new(ErrorKind::WriteZero, "write zero"));
+ }
+
+ // Prime compressor with first character.
+ last_byte = bytes[src_index];
+ src_index += 1;
+ bytes_pending += 1;
+
+ while src_count - 1 != 0 {
+ src_count -= 1;
+ curr_byte = bytes[src_index];
+ src_index += 1;
+ bytes_pending += 1;
+
+ if in_run {
+ if (curr_byte != last_byte) || (bytes_pending > MAX_BYTES) {
+ offset.get_or_insert(write_u8(&mut bufwriter, encode_rept(bytes_pending - 1))?);
+ write_u8(&mut bufwriter, last_byte)?;
+ bytes_written += 2;
+
+ bytes_pending = 1;
+ pending_index = src_index - 1;
+ run_index = 0;
+ in_run = false;
+ }
+ } else {
+ if bytes_pending > MAX_BYTES {
+ // We have as much differing data as we can output in one chunk.
+ // Output MAX_BYTES leaving one byte.
+ offset.get_or_insert(write_u8(&mut bufwriter, encode_diff(MAX_BYTES))?);
+ bufwriter.write(&bytes[pending_index..pending_index + MAX_BYTES as usize])?;
+ bytes_written += 1 + MAX_BYTES as u64;
+
+ pending_index += MAX_BYTES as usize;
+ bytes_pending -= MAX_BYTES;
+ run_index = bytes_pending - 1; // A run could start here
+ } else if curr_byte == last_byte {
+ if (bytes_pending - run_index >= MIN_REPT) || (run_index == 0) {
+ // This is a worthwhile run
+ if run_index != 0 {
+ // Flush differing data out of input buffer
+ offset.get_or_insert(write_u8(&mut bufwriter, encode_diff(run_index))?);
+ bufwriter
+ .write(&bytes[pending_index..pending_index + run_index as usize])?;
+ bytes_written += 1 + run_index as u64;
+ }
+ bytes_pending -= run_index; // Length of run
+ in_run = true;
+ }
+ } else {
+ run_index = bytes_pending - 1; // A run could start here
+ }
+ }
+ last_byte = curr_byte;
+ }
+
+ // Output the remainder
+ if in_run {
+ bytes_written += 2;
+ offset.get_or_insert(write_u8(&mut bufwriter, encode_rept(bytes_pending))?);
+ write_u8(&mut bufwriter, last_byte)?;
+ } else {
+ bytes_written += 1 + bytes_pending as u64;
+ offset.get_or_insert(write_u8(&mut bufwriter, encode_diff(bytes_pending))?);
+ bufwriter.write(&bytes[pending_index..pending_index + bytes_pending as usize])?;
+ }
+
+ bufwriter.flush()?;
+ Ok(bytes_written)
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::encoder::compression::tests::TEST_DATA;
+ use std::io::Cursor;
+
+ #[test]
+ fn test_packbits_single_byte() {
+ // compress single byte
+ const UNCOMPRESSED_DATA: [u8; 1] = [0x3F];
+ const EXPECTED_COMPRESSED_DATA: [u8; 2] = [0x00, 0x3F];
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Packbits::default()
+ .write_to(&mut writer, &UNCOMPRESSED_DATA)
+ .unwrap();
+ assert_eq!(compressed_data, EXPECTED_COMPRESSED_DATA);
+ }
+
+ #[test]
+ fn test_packbits_rept() {
+ // compress buffer with repetitive sequence
+ const UNCOMPRESSED_DATA: &'static [u8] =
+ b"This strrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrring hangs.";
+ const EXPECTED_COMPRESSED_DATA: &'static [u8] = b"\x06This st\xD1r\x09ing hangs.";
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Packbits::default()
+ .write_to(&mut writer, UNCOMPRESSED_DATA)
+ .unwrap();
+ assert_eq!(compressed_data, EXPECTED_COMPRESSED_DATA);
+ }
+
+ #[test]
+ fn test_packbits_large_rept_nonrept() {
+ // compress buffer with large repetitive and non-repetitive sequence
+ let mut data = b"This st".to_vec();
+ for _i in 0..158 {
+ data.push(b'r');
+ }
+ data.extend_from_slice(b"ing hangs.");
+ for i in 0..158 {
+ data.push(i);
+ }
+
+ const EXPECTED_COMPRESSED_DATA: [u8; 182] = [
+ 0x06, 0x54, 0x68, 0x69, 0x73, 0x20, 0x73, 0x74, 0x81, 0x72, 0xE3, 0x72, 0x7F, 0x69,
+ 0x6E, 0x67, 0x20, 0x68, 0x61, 0x6E, 0x67, 0x73, 0x2E, 0x00, 0x01, 0x02, 0x03, 0x04,
+ 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12,
+ 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20,
+ 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E,
+ 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
+ 0x3D, 0x3E, 0x3F, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A,
+ 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
+ 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66,
+ 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74,
+ 0x75, 0x27, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F, 0x80, 0x81,
+ 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F,
+ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D,
+ ];
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Packbits::default()
+ .write_to(&mut writer, data.as_slice())
+ .unwrap();
+ assert_eq!(compressed_data, EXPECTED_COMPRESSED_DATA);
+ }
+
+ #[test]
+ fn test_packbits() {
+ // compress teststring
+ const EXPECTED_COMPRESSED_DATA: &'static [u8] =
+ b"\x3CThis is a string for checking various compression algorithms.";
+
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Packbits::default()
+ .write_to(&mut writer, TEST_DATA)
+ .unwrap();
+ assert_eq!(compressed_data, EXPECTED_COMPRESSED_DATA);
+ }
+}
diff --git a/vendor/tiff/src/encoder/compression/uncompressed.rs b/vendor/tiff/src/encoder/compression/uncompressed.rs
new file mode 100644
index 0000000..900426f
--- /dev/null
+++ b/vendor/tiff/src/encoder/compression/uncompressed.rs
@@ -0,0 +1,37 @@
+use crate::{encoder::compression::*, tags::CompressionMethod};
+use std::io::Write;
+
+/// The default algorithm which does not compress at all.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub struct Uncompressed;
+
+impl Compression for Uncompressed {
+ const COMPRESSION_METHOD: CompressionMethod = CompressionMethod::None;
+
+ fn get_algorithm(&self) -> Compressor {
+ Compressor::Uncompressed(*self)
+ }
+}
+
+impl CompressionAlgorithm for Uncompressed {
+ fn write_to<W: Write>(&mut self, writer: &mut W, bytes: &[u8]) -> Result<u64, io::Error> {
+ writer.write(bytes).map(|byte_count| byte_count as u64)
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+ use crate::encoder::compression::tests::TEST_DATA;
+ use std::io::Cursor;
+
+ #[test]
+ fn test_no_compression() {
+ let mut compressed_data = Vec::<u8>::new();
+ let mut writer = Cursor::new(&mut compressed_data);
+ Uncompressed::default()
+ .write_to(&mut writer, TEST_DATA)
+ .unwrap();
+ assert_eq!(TEST_DATA, compressed_data);
+ }
+}