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-rw-r--r--vendor/image/src/codecs/bmp/decoder.rs1483
1 files changed, 1483 insertions, 0 deletions
diff --git a/vendor/image/src/codecs/bmp/decoder.rs b/vendor/image/src/codecs/bmp/decoder.rs
new file mode 100644
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--- /dev/null
+++ b/vendor/image/src/codecs/bmp/decoder.rs
@@ -0,0 +1,1483 @@
+use std::cmp::{self, Ordering};
+use std::convert::TryFrom;
+use std::io::{self, Cursor, Read, Seek, SeekFrom};
+use std::iter::{repeat, Iterator, Rev};
+use std::marker::PhantomData;
+use std::slice::ChunksMut;
+use std::{error, fmt, mem};
+
+use byteorder::{LittleEndian, ReadBytesExt};
+
+use crate::color::ColorType;
+use crate::error::{
+ DecodingError, ImageError, ImageResult, UnsupportedError, UnsupportedErrorKind,
+};
+use crate::image::{self, ImageDecoder, ImageDecoderRect, ImageFormat, Progress};
+
+const BITMAPCOREHEADER_SIZE: u32 = 12;
+const BITMAPINFOHEADER_SIZE: u32 = 40;
+const BITMAPV2HEADER_SIZE: u32 = 52;
+const BITMAPV3HEADER_SIZE: u32 = 56;
+const BITMAPV4HEADER_SIZE: u32 = 108;
+const BITMAPV5HEADER_SIZE: u32 = 124;
+
+static LOOKUP_TABLE_3_BIT_TO_8_BIT: [u8; 8] = [0, 36, 73, 109, 146, 182, 219, 255];
+static LOOKUP_TABLE_4_BIT_TO_8_BIT: [u8; 16] = [
+ 0, 17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204, 221, 238, 255,
+];
+static LOOKUP_TABLE_5_BIT_TO_8_BIT: [u8; 32] = [
+ 0, 8, 16, 25, 33, 41, 49, 58, 66, 74, 82, 90, 99, 107, 115, 123, 132, 140, 148, 156, 165, 173,
+ 181, 189, 197, 206, 214, 222, 230, 239, 247, 255,
+];
+static LOOKUP_TABLE_6_BIT_TO_8_BIT: [u8; 64] = [
+ 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93,
+ 97, 101, 105, 109, 113, 117, 121, 125, 130, 134, 138, 142, 146, 150, 154, 158, 162, 166, 170,
+ 174, 178, 182, 186, 190, 194, 198, 202, 206, 210, 215, 219, 223, 227, 231, 235, 239, 243, 247,
+ 251, 255,
+];
+
+static R5_G5_B5_COLOR_MASK: Bitfields = Bitfields {
+ r: Bitfield { len: 5, shift: 10 },
+ g: Bitfield { len: 5, shift: 5 },
+ b: Bitfield { len: 5, shift: 0 },
+ a: Bitfield { len: 0, shift: 0 },
+};
+const R8_G8_B8_COLOR_MASK: Bitfields = Bitfields {
+ r: Bitfield { len: 8, shift: 24 },
+ g: Bitfield { len: 8, shift: 16 },
+ b: Bitfield { len: 8, shift: 8 },
+ a: Bitfield { len: 0, shift: 0 },
+};
+const R8_G8_B8_A8_COLOR_MASK: Bitfields = Bitfields {
+ r: Bitfield { len: 8, shift: 16 },
+ g: Bitfield { len: 8, shift: 8 },
+ b: Bitfield { len: 8, shift: 0 },
+ a: Bitfield { len: 8, shift: 24 },
+};
+
+const RLE_ESCAPE: u8 = 0;
+const RLE_ESCAPE_EOL: u8 = 0;
+const RLE_ESCAPE_EOF: u8 = 1;
+const RLE_ESCAPE_DELTA: u8 = 2;
+
+/// The maximum width/height the decoder will process.
+const MAX_WIDTH_HEIGHT: i32 = 0xFFFF;
+
+#[derive(PartialEq, Copy, Clone)]
+enum ImageType {
+ Palette,
+ RGB16,
+ RGB24,
+ RGB32,
+ RGBA32,
+ RLE8,
+ RLE4,
+ Bitfields16,
+ Bitfields32,
+}
+
+#[derive(PartialEq)]
+enum BMPHeaderType {
+ Core,
+ Info,
+ V2,
+ V3,
+ V4,
+ V5,
+}
+
+#[derive(PartialEq)]
+enum FormatFullBytes {
+ RGB24,
+ RGB32,
+ RGBA32,
+ Format888,
+}
+
+enum Chunker<'a> {
+ FromTop(ChunksMut<'a, u8>),
+ FromBottom(Rev<ChunksMut<'a, u8>>),
+}
+
+pub(crate) struct RowIterator<'a> {
+ chunks: Chunker<'a>,
+}
+
+impl<'a> Iterator for RowIterator<'a> {
+ type Item = &'a mut [u8];
+
+ #[inline(always)]
+ fn next(&mut self) -> Option<&'a mut [u8]> {
+ match self.chunks {
+ Chunker::FromTop(ref mut chunks) => chunks.next(),
+ Chunker::FromBottom(ref mut chunks) => chunks.next(),
+ }
+ }
+}
+
+/// All errors that can occur when attempting to parse a BMP
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
+enum DecoderError {
+ // Failed to decompress RLE data.
+ CorruptRleData,
+
+ /// The bitfield mask interleaves set and unset bits
+ BitfieldMaskNonContiguous,
+ /// Bitfield mask invalid (e.g. too long for specified type)
+ BitfieldMaskInvalid,
+ /// Bitfield (of the specified width – 16- or 32-bit) mask not present
+ BitfieldMaskMissing(u32),
+ /// Bitfield (of the specified width – 16- or 32-bit) masks not present
+ BitfieldMasksMissing(u32),
+
+ /// BMP's "BM" signature wrong or missing
+ BmpSignatureInvalid,
+ /// More than the exactly one allowed plane specified by the format
+ MoreThanOnePlane,
+ /// Invalid amount of bits per channel for the specified image type
+ InvalidChannelWidth(ChannelWidthError, u16),
+
+ /// The width is negative
+ NegativeWidth(i32),
+ /// One of the dimensions is larger than a soft limit
+ ImageTooLarge(i32, i32),
+ /// The height is `i32::min_value()`
+ ///
+ /// General negative heights specify top-down DIBs
+ InvalidHeight,
+
+ /// Specified image type is invalid for top-down BMPs (i.e. is compressed)
+ ImageTypeInvalidForTopDown(u32),
+ /// Image type not currently recognized by the decoder
+ ImageTypeUnknown(u32),
+
+ /// Bitmap header smaller than the core header
+ HeaderTooSmall(u32),
+
+ /// The palette is bigger than allowed by the bit count of the BMP
+ PaletteSizeExceeded {
+ colors_used: u32,
+ bit_count: u16,
+ },
+}
+
+impl fmt::Display for DecoderError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ match self {
+ DecoderError::CorruptRleData => f.write_str("Corrupt RLE data"),
+ DecoderError::BitfieldMaskNonContiguous => f.write_str("Non-contiguous bitfield mask"),
+ DecoderError::BitfieldMaskInvalid => f.write_str("Invalid bitfield mask"),
+ DecoderError::BitfieldMaskMissing(bb) => {
+ f.write_fmt(format_args!("Missing {}-bit bitfield mask", bb))
+ }
+ DecoderError::BitfieldMasksMissing(bb) => {
+ f.write_fmt(format_args!("Missing {}-bit bitfield masks", bb))
+ }
+ DecoderError::BmpSignatureInvalid => f.write_str("BMP signature not found"),
+ DecoderError::MoreThanOnePlane => f.write_str("More than one plane"),
+ DecoderError::InvalidChannelWidth(tp, n) => {
+ f.write_fmt(format_args!("Invalid channel bit count for {}: {}", tp, n))
+ }
+ DecoderError::NegativeWidth(w) => f.write_fmt(format_args!("Negative width ({})", w)),
+ DecoderError::ImageTooLarge(w, h) => f.write_fmt(format_args!(
+ "Image too large (one of ({}, {}) > soft limit of {})",
+ w, h, MAX_WIDTH_HEIGHT
+ )),
+ DecoderError::InvalidHeight => f.write_str("Invalid height"),
+ DecoderError::ImageTypeInvalidForTopDown(tp) => f.write_fmt(format_args!(
+ "Invalid image type {} for top-down image.",
+ tp
+ )),
+ DecoderError::ImageTypeUnknown(tp) => {
+ f.write_fmt(format_args!("Unknown image compression type {}", tp))
+ }
+ DecoderError::HeaderTooSmall(s) => {
+ f.write_fmt(format_args!("Bitmap header too small ({} bytes)", s))
+ }
+ DecoderError::PaletteSizeExceeded {
+ colors_used,
+ bit_count,
+ } => f.write_fmt(format_args!(
+ "Palette size {} exceeds maximum size for BMP with bit count of {}",
+ colors_used, bit_count
+ )),
+ }
+ }
+}
+
+impl From<DecoderError> for ImageError {
+ fn from(e: DecoderError) -> ImageError {
+ ImageError::Decoding(DecodingError::new(ImageFormat::Bmp.into(), e))
+ }
+}
+
+impl error::Error for DecoderError {}
+
+/// Distinct image types whose saved channel width can be invalid
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
+enum ChannelWidthError {
+ /// RGB
+ Rgb,
+ /// 8-bit run length encoding
+ Rle8,
+ /// 4-bit run length encoding
+ Rle4,
+ /// Bitfields (16- or 32-bit)
+ Bitfields,
+}
+
+impl fmt::Display for ChannelWidthError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.write_str(match self {
+ ChannelWidthError::Rgb => "RGB",
+ ChannelWidthError::Rle8 => "RLE8",
+ ChannelWidthError::Rle4 => "RLE4",
+ ChannelWidthError::Bitfields => "bitfields",
+ })
+ }
+}
+
+/// Convenience function to check if the combination of width, length and number of
+/// channels would result in a buffer that would overflow.
+fn check_for_overflow(width: i32, length: i32, channels: usize) -> ImageResult<()> {
+ num_bytes(width, length, channels)
+ .map(|_| ())
+ .ok_or_else(|| {
+ ImageError::Unsupported(UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::GenericFeature(format!(
+ "Image dimensions ({}x{} w/{} channels) are too large",
+ width, length, channels
+ )),
+ ))
+ })
+}
+
+/// Calculate how many many bytes a buffer holding a decoded image with these properties would
+/// require. Returns `None` if the buffer size would overflow or if one of the sizes are negative.
+fn num_bytes(width: i32, length: i32, channels: usize) -> Option<usize> {
+ if width <= 0 || length <= 0 {
+ None
+ } else {
+ match channels.checked_mul(width as usize) {
+ Some(n) => n.checked_mul(length as usize),
+ None => None,
+ }
+ }
+}
+
+/// Call the provided function on each row of the provided buffer, returning Err if the provided
+/// function returns an error, extends the buffer if it's not large enough.
+fn with_rows<F>(
+ buffer: &mut [u8],
+ width: i32,
+ height: i32,
+ channels: usize,
+ top_down: bool,
+ mut func: F,
+) -> io::Result<()>
+where
+ F: FnMut(&mut [u8]) -> io::Result<()>,
+{
+ // An overflow should already have been checked for when this is called,
+ // though we check anyhow, as it somehow seems to increase performance slightly.
+ let row_width = channels.checked_mul(width as usize).unwrap();
+ let full_image_size = row_width.checked_mul(height as usize).unwrap();
+ assert_eq!(buffer.len(), full_image_size);
+
+ if !top_down {
+ for row in buffer.chunks_mut(row_width).rev() {
+ func(row)?;
+ }
+ } else {
+ for row in buffer.chunks_mut(row_width) {
+ func(row)?;
+ }
+ }
+ Ok(())
+}
+
+fn set_8bit_pixel_run<'a, T: Iterator<Item = &'a u8>>(
+ pixel_iter: &mut ChunksMut<u8>,
+ palette: &[[u8; 3]],
+ indices: T,
+ n_pixels: usize,
+) -> bool {
+ for idx in indices.take(n_pixels) {
+ if let Some(pixel) = pixel_iter.next() {
+ let rgb = palette[*idx as usize];
+ pixel[0] = rgb[0];
+ pixel[1] = rgb[1];
+ pixel[2] = rgb[2];
+ } else {
+ return false;
+ }
+ }
+ true
+}
+
+fn set_4bit_pixel_run<'a, T: Iterator<Item = &'a u8>>(
+ pixel_iter: &mut ChunksMut<u8>,
+ palette: &[[u8; 3]],
+ indices: T,
+ mut n_pixels: usize,
+) -> bool {
+ for idx in indices {
+ macro_rules! set_pixel {
+ ($i:expr) => {
+ if n_pixels == 0 {
+ break;
+ }
+ if let Some(pixel) = pixel_iter.next() {
+ let rgb = palette[$i as usize];
+ pixel[0] = rgb[0];
+ pixel[1] = rgb[1];
+ pixel[2] = rgb[2];
+ } else {
+ return false;
+ }
+ n_pixels -= 1;
+ };
+ }
+ set_pixel!(idx >> 4);
+ set_pixel!(idx & 0xf);
+ }
+ true
+}
+
+#[rustfmt::skip]
+fn set_2bit_pixel_run<'a, T: Iterator<Item = &'a u8>>(
+ pixel_iter: &mut ChunksMut<u8>,
+ palette: &[[u8; 3]],
+ indices: T,
+ mut n_pixels: usize,
+) -> bool {
+ for idx in indices {
+ macro_rules! set_pixel {
+ ($i:expr) => {
+ if n_pixels == 0 {
+ break;
+ }
+ if let Some(pixel) = pixel_iter.next() {
+ let rgb = palette[$i as usize];
+ pixel[0] = rgb[0];
+ pixel[1] = rgb[1];
+ pixel[2] = rgb[2];
+ } else {
+ return false;
+ }
+ n_pixels -= 1;
+ };
+ }
+ set_pixel!((idx >> 6) & 0x3u8);
+ set_pixel!((idx >> 4) & 0x3u8);
+ set_pixel!((idx >> 2) & 0x3u8);
+ set_pixel!( idx & 0x3u8);
+ }
+ true
+}
+
+fn set_1bit_pixel_run<'a, T: Iterator<Item = &'a u8>>(
+ pixel_iter: &mut ChunksMut<u8>,
+ palette: &[[u8; 3]],
+ indices: T,
+) {
+ for idx in indices {
+ let mut bit = 0x80;
+ loop {
+ if let Some(pixel) = pixel_iter.next() {
+ let rgb = palette[((idx & bit) != 0) as usize];
+ pixel[0] = rgb[0];
+ pixel[1] = rgb[1];
+ pixel[2] = rgb[2];
+ } else {
+ return;
+ }
+
+ bit >>= 1;
+ if bit == 0 {
+ break;
+ }
+ }
+ }
+}
+
+#[derive(PartialEq, Eq)]
+struct Bitfield {
+ shift: u32,
+ len: u32,
+}
+
+impl Bitfield {
+ fn from_mask(mask: u32, max_len: u32) -> ImageResult<Bitfield> {
+ if mask == 0 {
+ return Ok(Bitfield { shift: 0, len: 0 });
+ }
+ let mut shift = mask.trailing_zeros();
+ let mut len = (!(mask >> shift)).trailing_zeros();
+ if len != mask.count_ones() {
+ return Err(DecoderError::BitfieldMaskNonContiguous.into());
+ }
+ if len + shift > max_len {
+ return Err(DecoderError::BitfieldMaskInvalid.into());
+ }
+ if len > 8 {
+ shift += len - 8;
+ len = 8;
+ }
+ Ok(Bitfield { shift, len })
+ }
+
+ fn read(&self, data: u32) -> u8 {
+ let data = data >> self.shift;
+ match self.len {
+ 1 => ((data & 0b1) * 0xff) as u8,
+ 2 => ((data & 0b11) * 0x55) as u8,
+ 3 => LOOKUP_TABLE_3_BIT_TO_8_BIT[(data & 0b00_0111) as usize],
+ 4 => LOOKUP_TABLE_4_BIT_TO_8_BIT[(data & 0b00_1111) as usize],
+ 5 => LOOKUP_TABLE_5_BIT_TO_8_BIT[(data & 0b01_1111) as usize],
+ 6 => LOOKUP_TABLE_6_BIT_TO_8_BIT[(data & 0b11_1111) as usize],
+ 7 => ((data & 0x7f) << 1 | (data & 0x7f) >> 6) as u8,
+ 8 => (data & 0xff) as u8,
+ _ => panic!(),
+ }
+ }
+}
+
+#[derive(PartialEq, Eq)]
+struct Bitfields {
+ r: Bitfield,
+ g: Bitfield,
+ b: Bitfield,
+ a: Bitfield,
+}
+
+impl Bitfields {
+ fn from_mask(
+ r_mask: u32,
+ g_mask: u32,
+ b_mask: u32,
+ a_mask: u32,
+ max_len: u32,
+ ) -> ImageResult<Bitfields> {
+ let bitfields = Bitfields {
+ r: Bitfield::from_mask(r_mask, max_len)?,
+ g: Bitfield::from_mask(g_mask, max_len)?,
+ b: Bitfield::from_mask(b_mask, max_len)?,
+ a: Bitfield::from_mask(a_mask, max_len)?,
+ };
+ if bitfields.r.len == 0 || bitfields.g.len == 0 || bitfields.b.len == 0 {
+ return Err(DecoderError::BitfieldMaskMissing(max_len).into());
+ }
+ Ok(bitfields)
+ }
+}
+
+/// A bmp decoder
+pub struct BmpDecoder<R> {
+ reader: R,
+
+ bmp_header_type: BMPHeaderType,
+ indexed_color: bool,
+
+ width: i32,
+ height: i32,
+ data_offset: u64,
+ top_down: bool,
+ no_file_header: bool,
+ add_alpha_channel: bool,
+ has_loaded_metadata: bool,
+ image_type: ImageType,
+
+ bit_count: u16,
+ colors_used: u32,
+ palette: Option<Vec<[u8; 3]>>,
+ bitfields: Option<Bitfields>,
+}
+
+enum RLEInsn {
+ EndOfFile,
+ EndOfRow,
+ Delta(u8, u8),
+ Absolute(u8, Vec<u8>),
+ PixelRun(u8, u8),
+}
+
+impl<R: Read + Seek> BmpDecoder<R> {
+ fn new_decoder(reader: R) -> BmpDecoder<R> {
+ BmpDecoder {
+ reader,
+
+ bmp_header_type: BMPHeaderType::Info,
+ indexed_color: false,
+
+ width: 0,
+ height: 0,
+ data_offset: 0,
+ top_down: false,
+ no_file_header: false,
+ add_alpha_channel: false,
+ has_loaded_metadata: false,
+ image_type: ImageType::Palette,
+
+ bit_count: 0,
+ colors_used: 0,
+ palette: None,
+ bitfields: None,
+ }
+ }
+
+ /// Create a new decoder that decodes from the stream ```r```
+ pub fn new(reader: R) -> ImageResult<BmpDecoder<R>> {
+ let mut decoder = Self::new_decoder(reader);
+ decoder.read_metadata()?;
+ Ok(decoder)
+ }
+
+ /// Create a new decoder that decodes from the stream ```r``` without first
+ /// reading a BITMAPFILEHEADER. This is useful for decoding the CF_DIB format
+ /// directly from the Windows clipboard.
+ pub fn new_without_file_header(reader: R) -> ImageResult<BmpDecoder<R>> {
+ let mut decoder = Self::new_decoder(reader);
+ decoder.no_file_header = true;
+ decoder.read_metadata()?;
+ Ok(decoder)
+ }
+
+ #[cfg(feature = "ico")]
+ pub(crate) fn new_with_ico_format(reader: R) -> ImageResult<BmpDecoder<R>> {
+ let mut decoder = Self::new_decoder(reader);
+ decoder.read_metadata_in_ico_format()?;
+ Ok(decoder)
+ }
+
+ /// If true, the palette in BMP does not apply to the image even if it is found.
+ /// In other words, the output image is the indexed color.
+ pub fn set_indexed_color(&mut self, indexed_color: bool) {
+ self.indexed_color = indexed_color;
+ }
+
+ #[cfg(feature = "ico")]
+ pub(crate) fn reader(&mut self) -> &mut R {
+ &mut self.reader
+ }
+
+ fn read_file_header(&mut self) -> ImageResult<()> {
+ if self.no_file_header {
+ return Ok(());
+ }
+ let mut signature = [0; 2];
+ self.reader.read_exact(&mut signature)?;
+
+ if signature != b"BM"[..] {
+ return Err(DecoderError::BmpSignatureInvalid.into());
+ }
+
+ // The next 8 bytes represent file size, followed the 4 reserved bytes
+ // We're not interesting these values
+ self.reader.read_u32::<LittleEndian>()?;
+ self.reader.read_u32::<LittleEndian>()?;
+
+ self.data_offset = u64::from(self.reader.read_u32::<LittleEndian>()?);
+
+ Ok(())
+ }
+
+ /// Read BITMAPCOREHEADER https://msdn.microsoft.com/en-us/library/vs/alm/dd183372(v=vs.85).aspx
+ ///
+ /// returns Err if any of the values are invalid.
+ fn read_bitmap_core_header(&mut self) -> ImageResult<()> {
+ // As height/width values in BMP files with core headers are only 16 bits long,
+ // they won't be larger than `MAX_WIDTH_HEIGHT`.
+ self.width = i32::from(self.reader.read_u16::<LittleEndian>()?);
+ self.height = i32::from(self.reader.read_u16::<LittleEndian>()?);
+
+ check_for_overflow(self.width, self.height, self.num_channels())?;
+
+ // Number of planes (format specifies that this should be 1).
+ if self.reader.read_u16::<LittleEndian>()? != 1 {
+ return Err(DecoderError::MoreThanOnePlane.into());
+ }
+
+ self.bit_count = self.reader.read_u16::<LittleEndian>()?;
+ self.image_type = match self.bit_count {
+ 1 | 4 | 8 => ImageType::Palette,
+ 24 => ImageType::RGB24,
+ _ => {
+ return Err(DecoderError::InvalidChannelWidth(
+ ChannelWidthError::Rgb,
+ self.bit_count,
+ )
+ .into())
+ }
+ };
+
+ Ok(())
+ }
+
+ /// Read BITMAPINFOHEADER https://msdn.microsoft.com/en-us/library/vs/alm/dd183376(v=vs.85).aspx
+ /// or BITMAPV{2|3|4|5}HEADER.
+ ///
+ /// returns Err if any of the values are invalid.
+ fn read_bitmap_info_header(&mut self) -> ImageResult<()> {
+ self.width = self.reader.read_i32::<LittleEndian>()?;
+ self.height = self.reader.read_i32::<LittleEndian>()?;
+
+ // Width can not be negative
+ if self.width < 0 {
+ return Err(DecoderError::NegativeWidth(self.width).into());
+ } else if self.width > MAX_WIDTH_HEIGHT || self.height > MAX_WIDTH_HEIGHT {
+ // Limit very large image sizes to avoid OOM issues. Images with these sizes are
+ // unlikely to be valid anyhow.
+ return Err(DecoderError::ImageTooLarge(self.width, self.height).into());
+ }
+
+ if self.height == i32::min_value() {
+ return Err(DecoderError::InvalidHeight.into());
+ }
+
+ // A negative height indicates a top-down DIB.
+ if self.height < 0 {
+ self.height *= -1;
+ self.top_down = true;
+ }
+
+ check_for_overflow(self.width, self.height, self.num_channels())?;
+
+ // Number of planes (format specifies that this should be 1).
+ if self.reader.read_u16::<LittleEndian>()? != 1 {
+ return Err(DecoderError::MoreThanOnePlane.into());
+ }
+
+ self.bit_count = self.reader.read_u16::<LittleEndian>()?;
+ let image_type_u32 = self.reader.read_u32::<LittleEndian>()?;
+
+ // Top-down dibs can not be compressed.
+ if self.top_down && image_type_u32 != 0 && image_type_u32 != 3 {
+ return Err(DecoderError::ImageTypeInvalidForTopDown(image_type_u32).into());
+ }
+ self.image_type = match image_type_u32 {
+ 0 => match self.bit_count {
+ 1 | 2 | 4 | 8 => ImageType::Palette,
+ 16 => ImageType::RGB16,
+ 24 => ImageType::RGB24,
+ 32 if self.add_alpha_channel => ImageType::RGBA32,
+ 32 => ImageType::RGB32,
+ _ => {
+ return Err(DecoderError::InvalidChannelWidth(
+ ChannelWidthError::Rgb,
+ self.bit_count,
+ )
+ .into())
+ }
+ },
+ 1 => match self.bit_count {
+ 8 => ImageType::RLE8,
+ _ => {
+ return Err(DecoderError::InvalidChannelWidth(
+ ChannelWidthError::Rle8,
+ self.bit_count,
+ )
+ .into())
+ }
+ },
+ 2 => match self.bit_count {
+ 4 => ImageType::RLE4,
+ _ => {
+ return Err(DecoderError::InvalidChannelWidth(
+ ChannelWidthError::Rle4,
+ self.bit_count,
+ )
+ .into())
+ }
+ },
+ 3 => match self.bit_count {
+ 16 => ImageType::Bitfields16,
+ 32 => ImageType::Bitfields32,
+ _ => {
+ return Err(DecoderError::InvalidChannelWidth(
+ ChannelWidthError::Bitfields,
+ self.bit_count,
+ )
+ .into())
+ }
+ },
+ 4 => {
+ // JPEG compression is not implemented yet.
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::GenericFeature("JPEG compression".to_owned()),
+ ),
+ ));
+ }
+ 5 => {
+ // PNG compression is not implemented yet.
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::GenericFeature("PNG compression".to_owned()),
+ ),
+ ));
+ }
+ 11 | 12 | 13 => {
+ // CMYK types are not implemented yet.
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::GenericFeature("CMYK format".to_owned()),
+ ),
+ ));
+ }
+ _ => {
+ // Unknown compression type.
+ return Err(DecoderError::ImageTypeUnknown(image_type_u32).into());
+ }
+ };
+
+ // The next 12 bytes represent data array size in bytes,
+ // followed the horizontal and vertical printing resolutions
+ // We will calculate the pixel array size using width & height of image
+ // We're not interesting the horz or vert printing resolutions
+ self.reader.read_u32::<LittleEndian>()?;
+ self.reader.read_u32::<LittleEndian>()?;
+ self.reader.read_u32::<LittleEndian>()?;
+
+ self.colors_used = self.reader.read_u32::<LittleEndian>()?;
+
+ // The next 4 bytes represent number of "important" colors
+ // We're not interested in this value, so we'll skip it
+ self.reader.read_u32::<LittleEndian>()?;
+
+ Ok(())
+ }
+
+ fn read_bitmasks(&mut self) -> ImageResult<()> {
+ let r_mask = self.reader.read_u32::<LittleEndian>()?;
+ let g_mask = self.reader.read_u32::<LittleEndian>()?;
+ let b_mask = self.reader.read_u32::<LittleEndian>()?;
+
+ let a_mask = match self.bmp_header_type {
+ BMPHeaderType::V3 | BMPHeaderType::V4 | BMPHeaderType::V5 => {
+ self.reader.read_u32::<LittleEndian>()?
+ }
+ _ => 0,
+ };
+
+ self.bitfields = match self.image_type {
+ ImageType::Bitfields16 => {
+ Some(Bitfields::from_mask(r_mask, g_mask, b_mask, a_mask, 16)?)
+ }
+ ImageType::Bitfields32 => {
+ Some(Bitfields::from_mask(r_mask, g_mask, b_mask, a_mask, 32)?)
+ }
+ _ => None,
+ };
+
+ if self.bitfields.is_some() && a_mask != 0 {
+ self.add_alpha_channel = true;
+ }
+
+ Ok(())
+ }
+
+ fn read_metadata(&mut self) -> ImageResult<()> {
+ if !self.has_loaded_metadata {
+ self.read_file_header()?;
+ let bmp_header_offset = self.reader.stream_position()?;
+ let bmp_header_size = self.reader.read_u32::<LittleEndian>()?;
+ let bmp_header_end = bmp_header_offset + u64::from(bmp_header_size);
+
+ self.bmp_header_type = match bmp_header_size {
+ BITMAPCOREHEADER_SIZE => BMPHeaderType::Core,
+ BITMAPINFOHEADER_SIZE => BMPHeaderType::Info,
+ BITMAPV2HEADER_SIZE => BMPHeaderType::V2,
+ BITMAPV3HEADER_SIZE => BMPHeaderType::V3,
+ BITMAPV4HEADER_SIZE => BMPHeaderType::V4,
+ BITMAPV5HEADER_SIZE => BMPHeaderType::V5,
+ _ if bmp_header_size < BITMAPCOREHEADER_SIZE => {
+ // Size of any valid header types won't be smaller than core header type.
+ return Err(DecoderError::HeaderTooSmall(bmp_header_size).into());
+ }
+ _ => {
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::GenericFeature(format!(
+ "Unknown bitmap header type (size={})",
+ bmp_header_size
+ )),
+ ),
+ ))
+ }
+ };
+
+ match self.bmp_header_type {
+ BMPHeaderType::Core => {
+ self.read_bitmap_core_header()?;
+ }
+ BMPHeaderType::Info
+ | BMPHeaderType::V2
+ | BMPHeaderType::V3
+ | BMPHeaderType::V4
+ | BMPHeaderType::V5 => {
+ self.read_bitmap_info_header()?;
+ }
+ };
+
+ match self.image_type {
+ ImageType::Bitfields16 | ImageType::Bitfields32 => self.read_bitmasks()?,
+ _ => {}
+ };
+
+ self.reader.seek(SeekFrom::Start(bmp_header_end))?;
+
+ match self.image_type {
+ ImageType::Palette | ImageType::RLE4 | ImageType::RLE8 => self.read_palette()?,
+ _ => {}
+ };
+
+ if self.no_file_header {
+ // Use the offset of the end of metadata instead of reading a BMP file header.
+ self.data_offset = self.reader.stream_position()?;
+ }
+
+ self.has_loaded_metadata = true;
+ }
+ Ok(())
+ }
+
+ #[cfg(feature = "ico")]
+ #[doc(hidden)]
+ pub fn read_metadata_in_ico_format(&mut self) -> ImageResult<()> {
+ self.no_file_header = true;
+ self.add_alpha_channel = true;
+ self.read_metadata()?;
+
+ // The height field in an ICO file is doubled to account for the AND mask
+ // (whether or not an AND mask is actually present).
+ self.height /= 2;
+ Ok(())
+ }
+
+ fn get_palette_size(&mut self) -> ImageResult<usize> {
+ match self.colors_used {
+ 0 => Ok(1 << self.bit_count),
+ _ => {
+ if self.colors_used > 1 << self.bit_count {
+ return Err(DecoderError::PaletteSizeExceeded {
+ colors_used: self.colors_used,
+ bit_count: self.bit_count,
+ }
+ .into());
+ }
+ Ok(self.colors_used as usize)
+ }
+ }
+ }
+
+ fn bytes_per_color(&self) -> usize {
+ match self.bmp_header_type {
+ BMPHeaderType::Core => 3,
+ _ => 4,
+ }
+ }
+
+ fn read_palette(&mut self) -> ImageResult<()> {
+ const MAX_PALETTE_SIZE: usize = 256; // Palette indices are u8.
+
+ let bytes_per_color = self.bytes_per_color();
+ let palette_size = self.get_palette_size()?;
+ let max_length = MAX_PALETTE_SIZE * bytes_per_color;
+
+ let length = palette_size * bytes_per_color;
+ let mut buf = Vec::with_capacity(max_length);
+
+ // Resize and read the palette entries to the buffer.
+ // We limit the buffer to at most 256 colours to avoid any oom issues as
+ // 8-bit images can't reference more than 256 indexes anyhow.
+ buf.resize(cmp::min(length, max_length), 0);
+ self.reader.by_ref().read_exact(&mut buf)?;
+
+ // Allocate 256 entries even if palette_size is smaller, to prevent corrupt files from
+ // causing an out-of-bounds array access.
+ match length.cmp(&max_length) {
+ Ordering::Greater => {
+ self.reader
+ .seek(SeekFrom::Current((length - max_length) as i64))?;
+ }
+ Ordering::Less => buf.resize(max_length, 0),
+ Ordering::Equal => (),
+ }
+
+ let p: Vec<[u8; 3]> = (0..MAX_PALETTE_SIZE)
+ .map(|i| {
+ let b = buf[bytes_per_color * i];
+ let g = buf[bytes_per_color * i + 1];
+ let r = buf[bytes_per_color * i + 2];
+ [r, g, b]
+ })
+ .collect();
+
+ self.palette = Some(p);
+
+ Ok(())
+ }
+
+ /// Get the palette that is embedded in the BMP image, if any.
+ pub fn get_palette(&self) -> Option<&[[u8; 3]]> {
+ self.palette.as_ref().map(|vec| &vec[..])
+ }
+
+ fn num_channels(&self) -> usize {
+ if self.indexed_color {
+ 1
+ } else if self.add_alpha_channel {
+ 4
+ } else {
+ 3
+ }
+ }
+
+ fn rows<'a>(&self, pixel_data: &'a mut [u8]) -> RowIterator<'a> {
+ let stride = self.width as usize * self.num_channels();
+ if self.top_down {
+ RowIterator {
+ chunks: Chunker::FromTop(pixel_data.chunks_mut(stride)),
+ }
+ } else {
+ RowIterator {
+ chunks: Chunker::FromBottom(pixel_data.chunks_mut(stride).rev()),
+ }
+ }
+ }
+
+ fn read_palettized_pixel_data(&mut self, buf: &mut [u8]) -> ImageResult<()> {
+ let num_channels = self.num_channels();
+ let row_byte_length = ((i32::from(self.bit_count) * self.width + 31) / 32 * 4) as usize;
+ let mut indices = vec![0; row_byte_length];
+ let palette = self.palette.as_ref().unwrap();
+ let bit_count = self.bit_count;
+ let reader = &mut self.reader;
+ let width = self.width as usize;
+ let skip_palette = self.indexed_color;
+
+ reader.seek(SeekFrom::Start(self.data_offset))?;
+
+ if num_channels == 4 {
+ buf.chunks_exact_mut(4).for_each(|c| c[3] = 0xFF);
+ }
+
+ with_rows(
+ buf,
+ self.width,
+ self.height,
+ num_channels,
+ self.top_down,
+ |row| {
+ reader.read_exact(&mut indices)?;
+ if skip_palette {
+ row.clone_from_slice(&indices[0..width]);
+ } else {
+ let mut pixel_iter = row.chunks_mut(num_channels);
+ match bit_count {
+ 1 => {
+ set_1bit_pixel_run(&mut pixel_iter, palette, indices.iter());
+ }
+ 2 => {
+ set_2bit_pixel_run(&mut pixel_iter, palette, indices.iter(), width);
+ }
+ 4 => {
+ set_4bit_pixel_run(&mut pixel_iter, palette, indices.iter(), width);
+ }
+ 8 => {
+ set_8bit_pixel_run(&mut pixel_iter, palette, indices.iter(), width);
+ }
+ _ => panic!(),
+ };
+ }
+ Ok(())
+ },
+ )?;
+
+ Ok(())
+ }
+
+ fn read_16_bit_pixel_data(
+ &mut self,
+ buf: &mut [u8],
+ bitfields: Option<&Bitfields>,
+ ) -> ImageResult<()> {
+ let num_channels = self.num_channels();
+ let row_padding_len = self.width as usize % 2 * 2;
+ let row_padding = &mut [0; 2][..row_padding_len];
+ let bitfields = match bitfields {
+ Some(b) => b,
+ None => self.bitfields.as_ref().unwrap(),
+ };
+ let reader = &mut self.reader;
+
+ reader.seek(SeekFrom::Start(self.data_offset))?;
+
+ with_rows(
+ buf,
+ self.width,
+ self.height,
+ num_channels,
+ self.top_down,
+ |row| {
+ for pixel in row.chunks_mut(num_channels) {
+ let data = u32::from(reader.read_u16::<LittleEndian>()?);
+
+ pixel[0] = bitfields.r.read(data);
+ pixel[1] = bitfields.g.read(data);
+ pixel[2] = bitfields.b.read(data);
+ if num_channels == 4 {
+ if bitfields.a.len != 0 {
+ pixel[3] = bitfields.a.read(data);
+ } else {
+ pixel[3] = 0xFF;
+ }
+ }
+ }
+ reader.read_exact(row_padding)
+ },
+ )?;
+
+ Ok(())
+ }
+
+ /// Read image data from a reader in 32-bit formats that use bitfields.
+ fn read_32_bit_pixel_data(&mut self, buf: &mut [u8]) -> ImageResult<()> {
+ let num_channels = self.num_channels();
+
+ let bitfields = self.bitfields.as_ref().unwrap();
+
+ let reader = &mut self.reader;
+ reader.seek(SeekFrom::Start(self.data_offset))?;
+
+ with_rows(
+ buf,
+ self.width,
+ self.height,
+ num_channels,
+ self.top_down,
+ |row| {
+ for pixel in row.chunks_mut(num_channels) {
+ let data = reader.read_u32::<LittleEndian>()?;
+
+ pixel[0] = bitfields.r.read(data);
+ pixel[1] = bitfields.g.read(data);
+ pixel[2] = bitfields.b.read(data);
+ if num_channels == 4 {
+ if bitfields.a.len != 0 {
+ pixel[3] = bitfields.a.read(data);
+ } else {
+ pixel[3] = 0xff;
+ }
+ }
+ }
+ Ok(())
+ },
+ )?;
+
+ Ok(())
+ }
+
+ /// Read image data from a reader where the colours are stored as 8-bit values (24 or 32-bit).
+ fn read_full_byte_pixel_data(
+ &mut self,
+ buf: &mut [u8],
+ format: &FormatFullBytes,
+ ) -> ImageResult<()> {
+ let num_channels = self.num_channels();
+ let row_padding_len = match *format {
+ FormatFullBytes::RGB24 => (4 - (self.width as usize * 3) % 4) % 4,
+ _ => 0,
+ };
+ let row_padding = &mut [0; 4][..row_padding_len];
+
+ self.reader.seek(SeekFrom::Start(self.data_offset))?;
+
+ let reader = &mut self.reader;
+
+ with_rows(
+ buf,
+ self.width,
+ self.height,
+ num_channels,
+ self.top_down,
+ |row| {
+ for pixel in row.chunks_mut(num_channels) {
+ if *format == FormatFullBytes::Format888 {
+ reader.read_u8()?;
+ }
+
+ // Read the colour values (b, g, r).
+ // Reading 3 bytes and reversing them is significantly faster than reading one
+ // at a time.
+ reader.read_exact(&mut pixel[0..3])?;
+ pixel[0..3].reverse();
+
+ if *format == FormatFullBytes::RGB32 {
+ reader.read_u8()?;
+ }
+
+ // Read the alpha channel if present
+ if *format == FormatFullBytes::RGBA32 {
+ reader.read_exact(&mut pixel[3..4])?;
+ } else if num_channels == 4 {
+ pixel[3] = 0xFF;
+ }
+ }
+ reader.read_exact(row_padding)
+ },
+ )?;
+
+ Ok(())
+ }
+
+ fn read_rle_data(&mut self, buf: &mut [u8], image_type: ImageType) -> ImageResult<()> {
+ // Seek to the start of the actual image data.
+ self.reader.seek(SeekFrom::Start(self.data_offset))?;
+
+ let num_channels = self.num_channels();
+ let p = self.palette.as_ref().unwrap();
+
+ // Handling deltas in the RLE scheme means that we need to manually
+ // iterate through rows and pixels. Even if we didn't have to handle
+ // deltas, we have to ensure that a single runlength doesn't straddle
+ // two rows.
+ let mut row_iter = self.rows(buf);
+
+ while let Some(row) = row_iter.next() {
+ let mut pixel_iter = row.chunks_mut(num_channels);
+
+ let mut x = 0;
+ loop {
+ let instruction = {
+ let control_byte = self.reader.read_u8()?;
+ match control_byte {
+ RLE_ESCAPE => {
+ let op = self.reader.read_u8()?;
+
+ match op {
+ RLE_ESCAPE_EOL => RLEInsn::EndOfRow,
+ RLE_ESCAPE_EOF => RLEInsn::EndOfFile,
+ RLE_ESCAPE_DELTA => {
+ let xdelta = self.reader.read_u8()?;
+ let ydelta = self.reader.read_u8()?;
+ RLEInsn::Delta(xdelta, ydelta)
+ }
+ _ => {
+ let mut length = op as usize;
+ if self.image_type == ImageType::RLE4 {
+ length = (length + 1) / 2;
+ }
+ length += length & 1;
+ let mut buffer = vec![0; length];
+ self.reader.read_exact(&mut buffer)?;
+ RLEInsn::Absolute(op, buffer)
+ }
+ }
+ }
+ _ => {
+ let palette_index = self.reader.read_u8()?;
+ RLEInsn::PixelRun(control_byte, palette_index)
+ }
+ }
+ };
+
+ match instruction {
+ RLEInsn::EndOfFile => {
+ pixel_iter.for_each(|p| p.fill(0));
+ row_iter.for_each(|r| r.fill(0));
+ return Ok(());
+ }
+ RLEInsn::EndOfRow => {
+ pixel_iter.for_each(|p| p.fill(0));
+ break;
+ }
+ RLEInsn::Delta(x_delta, y_delta) => {
+ // The msdn site on bitmap compression doesn't specify
+ // what happens to the values skipped when encountering
+ // a delta code, however IE and the windows image
+ // preview seems to replace them with black pixels,
+ // so we stick to that.
+
+ if y_delta > 0 {
+ // Zero out the remainder of the current row.
+ pixel_iter.for_each(|p| p.fill(0));
+
+ // If any full rows are skipped, zero them out.
+ for _ in 1..y_delta {
+ let row = row_iter.next().ok_or(DecoderError::CorruptRleData)?;
+ row.fill(0);
+ }
+
+ // Set the pixel iterator to the start of the next row.
+ pixel_iter = row_iter
+ .next()
+ .ok_or(DecoderError::CorruptRleData)?
+ .chunks_mut(num_channels);
+
+ // Zero out the pixels up to the current point in the row.
+ for _ in 0..x {
+ pixel_iter
+ .next()
+ .ok_or(DecoderError::CorruptRleData)?
+ .fill(0);
+ }
+ }
+
+ for _ in 0..x_delta {
+ let pixel = pixel_iter.next().ok_or(DecoderError::CorruptRleData)?;
+ pixel.fill(0);
+ }
+ x += x_delta as usize;
+ }
+ RLEInsn::Absolute(length, indices) => {
+ // Absolute mode cannot span rows, so if we run
+ // out of pixels to process, we should stop
+ // processing the image.
+ match image_type {
+ ImageType::RLE8 => {
+ if !set_8bit_pixel_run(
+ &mut pixel_iter,
+ p,
+ indices.iter(),
+ length as usize,
+ ) {
+ return Err(DecoderError::CorruptRleData.into());
+ }
+ }
+ ImageType::RLE4 => {
+ if !set_4bit_pixel_run(
+ &mut pixel_iter,
+ p,
+ indices.iter(),
+ length as usize,
+ ) {
+ return Err(DecoderError::CorruptRleData.into());
+ }
+ }
+ _ => unreachable!(),
+ }
+ x += length as usize;
+ }
+ RLEInsn::PixelRun(n_pixels, palette_index) => {
+ // A pixel run isn't allowed to span rows, but we
+ // simply continue on to the next row if we run
+ // out of pixels to set.
+ match image_type {
+ ImageType::RLE8 => {
+ if !set_8bit_pixel_run(
+ &mut pixel_iter,
+ p,
+ repeat(&palette_index),
+ n_pixels as usize,
+ ) {
+ return Err(DecoderError::CorruptRleData.into());
+ }
+ }
+ ImageType::RLE4 => {
+ if !set_4bit_pixel_run(
+ &mut pixel_iter,
+ p,
+ repeat(&palette_index),
+ n_pixels as usize,
+ ) {
+ return Err(DecoderError::CorruptRleData.into());
+ }
+ }
+ _ => unreachable!(),
+ }
+ x += n_pixels as usize;
+ }
+ }
+ }
+ }
+
+ Ok(())
+ }
+
+ /// Read the actual data of the image. This function is deliberately not public because it
+ /// cannot be called multiple times without seeking back the underlying reader in between.
+ pub(crate) fn read_image_data(&mut self, buf: &mut [u8]) -> ImageResult<()> {
+ match self.image_type {
+ ImageType::Palette => self.read_palettized_pixel_data(buf),
+ ImageType::RGB16 => self.read_16_bit_pixel_data(buf, Some(&R5_G5_B5_COLOR_MASK)),
+ ImageType::RGB24 => self.read_full_byte_pixel_data(buf, &FormatFullBytes::RGB24),
+ ImageType::RGB32 => self.read_full_byte_pixel_data(buf, &FormatFullBytes::RGB32),
+ ImageType::RGBA32 => self.read_full_byte_pixel_data(buf, &FormatFullBytes::RGBA32),
+ ImageType::RLE8 => self.read_rle_data(buf, ImageType::RLE8),
+ ImageType::RLE4 => self.read_rle_data(buf, ImageType::RLE4),
+ ImageType::Bitfields16 => match self.bitfields {
+ Some(_) => self.read_16_bit_pixel_data(buf, None),
+ None => Err(DecoderError::BitfieldMasksMissing(16).into()),
+ },
+ ImageType::Bitfields32 => match self.bitfields {
+ Some(R8_G8_B8_COLOR_MASK) => {
+ self.read_full_byte_pixel_data(buf, &FormatFullBytes::Format888)
+ }
+ Some(R8_G8_B8_A8_COLOR_MASK) => {
+ self.read_full_byte_pixel_data(buf, &FormatFullBytes::RGBA32)
+ }
+ Some(_) => self.read_32_bit_pixel_data(buf),
+ None => Err(DecoderError::BitfieldMasksMissing(32).into()),
+ },
+ }
+ }
+}
+
+/// Wrapper struct around a `Cursor<Vec<u8>>`
+pub struct BmpReader<R>(Cursor<Vec<u8>>, PhantomData<R>);
+impl<R> Read for BmpReader<R> {
+ fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+ self.0.read(buf)
+ }
+ fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+ if self.0.position() == 0 && buf.is_empty() {
+ mem::swap(buf, self.0.get_mut());
+ Ok(buf.len())
+ } else {
+ self.0.read_to_end(buf)
+ }
+ }
+}
+
+impl<'a, R: 'a + Read + Seek> ImageDecoder<'a> for BmpDecoder<R> {
+ type Reader = BmpReader<R>;
+
+ fn dimensions(&self) -> (u32, u32) {
+ (self.width as u32, self.height as u32)
+ }
+
+ fn color_type(&self) -> ColorType {
+ if self.indexed_color {
+ ColorType::L8
+ } else if self.add_alpha_channel {
+ ColorType::Rgba8
+ } else {
+ ColorType::Rgb8
+ }
+ }
+
+ fn into_reader(self) -> ImageResult<Self::Reader> {
+ Ok(BmpReader(
+ Cursor::new(image::decoder_to_vec(self)?),
+ PhantomData,
+ ))
+ }
+
+ fn read_image(mut self, buf: &mut [u8]) -> ImageResult<()> {
+ assert_eq!(u64::try_from(buf.len()), Ok(self.total_bytes()));
+ self.read_image_data(buf)
+ }
+}
+
+impl<'a, R: 'a + Read + Seek> ImageDecoderRect<'a> for BmpDecoder<R> {
+ fn read_rect_with_progress<F: Fn(Progress)>(
+ &mut self,
+ x: u32,
+ y: u32,
+ width: u32,
+ height: u32,
+ buf: &mut [u8],
+ progress_callback: F,
+ ) -> ImageResult<()> {
+ let start = self.reader.stream_position()?;
+ image::load_rect(
+ x,
+ y,
+ width,
+ height,
+ buf,
+ progress_callback,
+ self,
+ |_, _| Ok(()),
+ |s, buf| s.read_image_data(buf),
+ )?;
+ self.reader.seek(SeekFrom::Start(start))?;
+ Ok(())
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+
+ #[test]
+ fn test_bitfield_len() {
+ for len in 1..9 {
+ let bitfield = Bitfield { shift: 0, len };
+ for i in 0..(1 << len) {
+ let read = bitfield.read(i);
+ let calc = (i as f64 / ((1 << len) - 1) as f64 * 255f64).round() as u8;
+ if read != calc {
+ println!("len:{} i:{} read:{} calc:{}", len, i, read, calc);
+ }
+ assert_eq!(read, calc);
+ }
+ }
+ }
+
+ #[test]
+ fn read_rect() {
+ let f = std::fs::File::open("tests/images/bmp/images/Core_8_Bit.bmp").unwrap();
+ let mut decoder = super::BmpDecoder::new(f).unwrap();
+
+ let mut buf: Vec<u8> = vec![0; 8 * 8 * 3];
+ decoder.read_rect(0, 0, 8, 8, &mut *buf).unwrap();
+ }
+
+ #[test]
+ fn read_rle_too_short() {
+ let data = vec![
+ 0x42, 0x4d, 0x04, 0xee, 0xfe, 0xff, 0xff, 0x10, 0xff, 0x00, 0x04, 0x00, 0x00, 0x00,
+ 0x7c, 0x00, 0x00, 0x00, 0x0c, 0x41, 0x00, 0x00, 0x07, 0x10, 0x00, 0x00, 0x01, 0x00,
+ 0x04, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0d, 0x00, 0x00, 0x00,
+ 0x00, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xfe, 0x21,
+ 0xff, 0x00, 0x66, 0x61, 0x72, 0x62, 0x66, 0x65, 0x6c, 0x64, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0xff, 0xd8, 0xff, 0x00, 0x00, 0x19, 0x51, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfa, 0xff, 0x00, 0x00, 0x00,
+ 0x00, 0x01, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0x00,
+ 0x00, 0x00, 0x00, 0x2d, 0x31, 0x31, 0x35, 0x36, 0x00, 0xff, 0x00, 0x00, 0x52, 0x3a,
+ 0x37, 0x30, 0x7e, 0x71, 0x63, 0x91, 0x5a, 0x04, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x2d, 0x35, 0x37, 0x00, 0xff, 0x00, 0x00, 0x52,
+ 0x3a, 0x37, 0x30, 0x7e, 0x71, 0x63, 0x91, 0x5a, 0x04, 0x05, 0x3c, 0x00, 0x00, 0x11,
+ 0x00, 0x5d, 0x7a, 0x82, 0xb7, 0xca, 0x2d, 0x31, 0xff, 0xff, 0xc7, 0x95, 0x33, 0x2e,
+ 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7c, 0x00,
+ 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x66, 0x00, 0x4d,
+ 0x4d, 0x00, 0x2a, 0x00,
+ ];
+
+ let decoder = BmpDecoder::new(Cursor::new(&data)).unwrap();
+ let mut buf = vec![0; usize::try_from(decoder.total_bytes()).unwrap()];
+ assert!(decoder.read_image(&mut buf).is_ok());
+ }
+
+ #[test]
+ fn test_no_header() {
+ let tests = [
+ "Info_R8_G8_B8.bmp",
+ "Info_A8_R8_G8_B8.bmp",
+ "Info_8_Bit.bmp",
+ "Info_4_Bit.bmp",
+ "Info_1_Bit.bmp",
+ ];
+
+ for name in &tests {
+ let path = format!("tests/images/bmp/images/{name}");
+ let ref_img = crate::open(&path).unwrap();
+ let mut data = std::fs::read(&path).unwrap();
+ // skip the BITMAPFILEHEADER
+ let slice = &mut data[14..];
+ let decoder = BmpDecoder::new_without_file_header(Cursor::new(slice)).unwrap();
+ let no_hdr_img = crate::DynamicImage::from_decoder(decoder).unwrap();
+ assert_eq!(ref_img, no_hdr_img);
+ }
+ }
+}
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