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-rw-r--r--third_party/rust/image/src/pnm/decoder.rs1104
1 files changed, 1104 insertions, 0 deletions
diff --git a/third_party/rust/image/src/pnm/decoder.rs b/third_party/rust/image/src/pnm/decoder.rs
new file mode 100644
index 0000000000..85c8e43787
--- /dev/null
+++ b/third_party/rust/image/src/pnm/decoder.rs
@@ -0,0 +1,1104 @@
+use std::convert::TryFrom;
+use std::io::{self, BufRead, BufReader, Cursor, Read};
+use std::str::{self, FromStr};
+use std::fmt::Display;
+use std::marker::PhantomData;
+use std::mem;
+
+use super::{ArbitraryHeader, ArbitraryTuplType, BitmapHeader, GraymapHeader, PixmapHeader};
+use super::{HeaderRecord, PNMHeader, PNMSubtype, SampleEncoding};
+use crate::color::{ColorType, ExtendedColorType};
+use crate::error::{ImageError, ImageResult};
+use crate::image::{self, ImageDecoder};
+use crate::utils;
+
+use byteorder::{BigEndian, ByteOrder, NativeEndian};
+
+/// Dynamic representation, represents all decodable (sample, depth) combinations.
+#[derive(Clone, Copy)]
+enum TupleType {
+ PbmBit,
+ BWBit,
+ GrayU8,
+ GrayU16,
+ RGBU8,
+ RGBU16,
+}
+
+trait Sample {
+ fn bytelen(width: u32, height: u32, samples: u32) -> ImageResult<usize>;
+
+ /// It is guaranteed that `bytes.len() == bytelen(width, height, samples)`
+ fn from_bytes(bytes: &[u8], width: u32, height: u32, samples: u32)
+ -> ImageResult<Vec<u8>>;
+
+ fn from_ascii(reader: &mut dyn Read, width: u32, height: u32, samples: u32)
+ -> ImageResult<Vec<u8>>;
+}
+
+struct U8;
+struct U16;
+struct PbmBit;
+struct BWBit;
+
+trait DecodableImageHeader {
+ fn tuple_type(&self) -> ImageResult<TupleType>;
+}
+
+/// PNM decoder
+pub struct PnmDecoder<R> {
+ reader: BufReader<R>,
+ header: PNMHeader,
+ tuple: TupleType,
+}
+
+impl<R: Read> PnmDecoder<R> {
+ /// Create a new decoder that decodes from the stream ```read```
+ pub fn new(read: R) -> ImageResult<PnmDecoder<R>> {
+ let mut buf = BufReader::new(read);
+ let magic = buf.read_magic_constant()?;
+ if magic[0] != b'P' {
+ return Err(ImageError::FormatError(
+ format!("Expected magic constant for pnm, P1 through P7 instead of {:?}", magic),
+ ));
+ }
+
+ let subtype = match magic[1] {
+ b'1' => PNMSubtype::Bitmap(SampleEncoding::Ascii),
+ b'2' => PNMSubtype::Graymap(SampleEncoding::Ascii),
+ b'3' => PNMSubtype::Pixmap(SampleEncoding::Ascii),
+ b'4' => PNMSubtype::Bitmap(SampleEncoding::Binary),
+ b'5' => PNMSubtype::Graymap(SampleEncoding::Binary),
+ b'6' => PNMSubtype::Pixmap(SampleEncoding::Binary),
+ b'7' => PNMSubtype::ArbitraryMap,
+ _ => {
+ return Err(ImageError::FormatError(
+ format!("Expected magic constant for pnm, P1 through P7 instead of {:?}", magic),
+ ));
+ }
+ };
+
+ match subtype {
+ PNMSubtype::Bitmap(enc) => PnmDecoder::read_bitmap_header(buf, enc),
+ PNMSubtype::Graymap(enc) => PnmDecoder::read_graymap_header(buf, enc),
+ PNMSubtype::Pixmap(enc) => PnmDecoder::read_pixmap_header(buf, enc),
+ PNMSubtype::ArbitraryMap => PnmDecoder::read_arbitrary_header(buf),
+ }
+ }
+
+ /// Extract the reader and header after an image has been read.
+ pub fn into_inner(self) -> (R, PNMHeader) {
+ (self.reader.into_inner(), self.header)
+ }
+
+ fn read_bitmap_header(
+ mut reader: BufReader<R>,
+ encoding: SampleEncoding,
+ ) -> ImageResult<PnmDecoder<R>> {
+ let header = reader.read_bitmap_header(encoding)?;
+ Ok(PnmDecoder {
+ reader,
+ tuple: TupleType::PbmBit,
+ header: PNMHeader {
+ decoded: HeaderRecord::Bitmap(header),
+ encoded: None,
+ },
+ })
+ }
+
+ fn read_graymap_header(
+ mut reader: BufReader<R>,
+ encoding: SampleEncoding,
+ ) -> ImageResult<PnmDecoder<R>> {
+ let header = reader.read_graymap_header(encoding)?;
+ let tuple_type = header.tuple_type()?;
+ Ok(PnmDecoder {
+ reader,
+ tuple: tuple_type,
+ header: PNMHeader {
+ decoded: HeaderRecord::Graymap(header),
+ encoded: None,
+ },
+ })
+ }
+
+ fn read_pixmap_header(
+ mut reader: BufReader<R>,
+ encoding: SampleEncoding,
+ ) -> ImageResult<PnmDecoder<R>> {
+ let header = reader.read_pixmap_header(encoding)?;
+ let tuple_type = header.tuple_type()?;
+ Ok(PnmDecoder {
+ reader,
+ tuple: tuple_type,
+ header: PNMHeader {
+ decoded: HeaderRecord::Pixmap(header),
+ encoded: None,
+ },
+ })
+ }
+
+ fn read_arbitrary_header(mut reader: BufReader<R>) -> ImageResult<PnmDecoder<R>> {
+ let header = reader.read_arbitrary_header()?;
+ let tuple_type = header.tuple_type()?;
+ Ok(PnmDecoder {
+ reader,
+ tuple: tuple_type,
+ header: PNMHeader {
+ decoded: HeaderRecord::Arbitrary(header),
+ encoded: None,
+ },
+ })
+ }
+}
+
+trait HeaderReader: BufRead {
+ /// Reads the two magic constant bytes
+ fn read_magic_constant(&mut self) -> ImageResult<[u8; 2]> {
+ let mut magic: [u8; 2] = [0, 0];
+ self.read_exact(&mut magic)
+ .map_err(ImageError::IoError)?;
+ Ok(magic)
+ }
+
+ /// Reads a string as well as a single whitespace after it, ignoring comments
+ fn read_next_string(&mut self) -> ImageResult<String> {
+ let mut bytes = Vec::new();
+
+ // pair input bytes with a bool mask to remove comments
+ let mark_comments = self.bytes().scan(true, |partof, read| {
+ let byte = match read {
+ Err(err) => return Some((*partof, Err(err))),
+ Ok(byte) => byte,
+ };
+ let cur_enabled = *partof && byte != b'#';
+ let next_enabled = cur_enabled || (byte == b'\r' || byte == b'\n');
+ *partof = next_enabled;
+ Some((cur_enabled, Ok(byte)))
+ });
+
+ for (_, byte) in mark_comments.filter(|ref e| e.0) {
+ match byte {
+ Ok(b'\t') | Ok(b'\n') | Ok(b'\x0b') | Ok(b'\x0c') | Ok(b'\r') | Ok(b' ') => {
+ if !bytes.is_empty() {
+ break; // We're done as we already have some content
+ }
+ }
+ Ok(byte) if !byte.is_ascii() => {
+ return Err(ImageError::FormatError(
+ format!("Non ascii character {} in header", byte),
+ ));
+ },
+ Ok(byte) => {
+ bytes.push(byte);
+ },
+ Err(_) => break,
+ }
+ }
+
+ if bytes.is_empty() {
+ return Err(ImageError::IoError(io::ErrorKind::UnexpectedEof.into()));
+ }
+
+ if !bytes.as_slice().is_ascii() {
+ // We have only filled the buffer with characters for which `byte.is_ascii()` holds.
+ unreachable!("Non ascii character should have returned sooner")
+ }
+
+ let string = String::from_utf8(bytes)
+ // We checked the precondition ourselves a few lines before, `bytes.as_slice().is_ascii()`.
+ .unwrap_or_else(|_| unreachable!("Only ascii characters should be decoded"));
+
+ Ok(string)
+ }
+
+ /// Read the next line
+ fn read_next_line(&mut self) -> ImageResult<String> {
+ let mut buffer = String::new();
+ self.read_line(&mut buffer)
+ .map_err(ImageError::IoError)?;
+ Ok(buffer)
+ }
+
+ fn read_next_u32(&mut self) -> ImageResult<u32> {
+ let s = self.read_next_string()?;
+ s.parse::<u32>()
+ .map_err(|err| ImageError::FormatError(
+ format!("Error parsing number {} in preamble: {}", s, err)
+ ))
+ }
+
+ fn read_bitmap_header(&mut self, encoding: SampleEncoding) -> ImageResult<BitmapHeader> {
+ let width = self.read_next_u32()?;
+ let height = self.read_next_u32()?;
+ Ok(BitmapHeader {
+ encoding,
+ width,
+ height,
+ })
+ }
+
+ fn read_graymap_header(&mut self, encoding: SampleEncoding) -> ImageResult<GraymapHeader> {
+ self.read_pixmap_header(encoding).map(
+ |PixmapHeader {
+ encoding,
+ width,
+ height,
+ maxval,
+ }| GraymapHeader {
+ encoding,
+ width,
+ height,
+ maxwhite: maxval,
+ },
+ )
+ }
+
+ fn read_pixmap_header(&mut self, encoding: SampleEncoding) -> ImageResult<PixmapHeader> {
+ let width = self.read_next_u32()?;
+ let height = self.read_next_u32()?;
+ let maxval = self.read_next_u32()?;
+ Ok(PixmapHeader {
+ encoding,
+ width,
+ height,
+ maxval,
+ })
+ }
+
+ fn read_arbitrary_header(&mut self) -> ImageResult<ArbitraryHeader> {
+ match self.bytes().next() {
+ None => return Err(ImageError::IoError(io::ErrorKind::UnexpectedEof.into())),
+ Some(Err(io)) => return Err(ImageError::IoError(io)),
+ Some(Ok(b'\n')) => (),
+ Some(Ok(c)) => {
+ return Err(ImageError::FormatError(
+ format!("Expected newline after P7 magic instead of {}", c),
+ ))
+ }
+ }
+
+ let mut line = String::new();
+ let mut height: Option<u32> = None;
+ let mut width: Option<u32> = None;
+ let mut depth: Option<u32> = None;
+ let mut maxval: Option<u32> = None;
+ let mut tupltype: Option<String> = None;
+ loop {
+ line.truncate(0);
+ let len = self.read_line(&mut line).map_err(ImageError::IoError)?;
+ if len == 0 {
+ return Err(ImageError::FormatError(
+ "Unexpected end of pnm header".to_string(),
+ ))
+ }
+ if line.as_bytes()[0] == b'#' {
+ continue;
+ }
+ if !line.is_ascii() {
+ return Err(ImageError::FormatError(
+ "Only ascii characters allowed in pam header".to_string(),
+ ));
+ }
+ #[allow(deprecated)]
+ let (identifier, rest) = line.trim_left()
+ .split_at(line.find(char::is_whitespace).unwrap_or_else(|| line.len()));
+ match identifier {
+ "ENDHDR" => break,
+ "HEIGHT" => if height.is_some() {
+ return Err(ImageError::FormatError("Duplicate HEIGHT line".to_string()));
+ } else {
+ let h = rest.trim()
+ .parse::<u32>()
+ .map_err(|err| ImageError::FormatError(
+ format!("Invalid height {}: {}", rest, err)
+ ))?;
+ height = Some(h);
+ },
+ "WIDTH" => if width.is_some() {
+ return Err(ImageError::FormatError("Duplicate WIDTH line".to_string()));
+ } else {
+ let w = rest.trim()
+ .parse::<u32>()
+ .map_err(|err| ImageError::FormatError(
+ format!("Invalid width {}: {}", rest, err)
+ ))?;
+ width = Some(w);
+ },
+ "DEPTH" => if depth.is_some() {
+ return Err(ImageError::FormatError("Duplicate DEPTH line".to_string()));
+ } else {
+ let d = rest.trim()
+ .parse::<u32>()
+ .map_err(|err| ImageError::FormatError(
+ format!("Invalid depth {}: {}", rest, err)
+ ))?;
+ depth = Some(d);
+ },
+ "MAXVAL" => if maxval.is_some() {
+ return Err(ImageError::FormatError("Duplicate MAXVAL line".to_string()));
+ } else {
+ let m = rest.trim()
+ .parse::<u32>()
+ .map_err(|err| ImageError::FormatError(
+ format!("Invalid maxval {}: {}", rest, err)
+ ))?;
+ maxval = Some(m);
+ },
+ "TUPLTYPE" => {
+ let identifier = rest.trim();
+ if tupltype.is_some() {
+ let appended = tupltype.take().map(|mut v| {
+ v.push(' ');
+ v.push_str(identifier);
+ v
+ });
+ tupltype = appended;
+ } else {
+ tupltype = Some(identifier.to_string());
+ }
+ }
+ _ => return Err(ImageError::FormatError("Unknown header line".to_string())),
+ }
+ }
+
+ let (h, w, d, m) = match (height, width, depth, maxval) {
+ (None, _, _, _) => {
+ return Err(ImageError::FormatError(
+ "Expected one HEIGHT line".to_string(),
+ ))
+ }
+ (_, None, _, _) => {
+ return Err(ImageError::FormatError(
+ "Expected one WIDTH line".to_string(),
+ ))
+ }
+ (_, _, None, _) => {
+ return Err(ImageError::FormatError(
+ "Expected one DEPTH line".to_string(),
+ ))
+ }
+ (_, _, _, None) => {
+ return Err(ImageError::FormatError(
+ "Expected one MAXVAL line".to_string(),
+ ))
+ }
+ (Some(h), Some(w), Some(d), Some(m)) => (h, w, d, m),
+ };
+
+ let tupltype = match tupltype {
+ None => None,
+ Some(ref t) if t == "BLACKANDWHITE" => Some(ArbitraryTuplType::BlackAndWhite),
+ Some(ref t) if t == "BLACKANDWHITE_ALPHA" => {
+ Some(ArbitraryTuplType::BlackAndWhiteAlpha)
+ }
+ Some(ref t) if t == "GRAYSCALE" => Some(ArbitraryTuplType::Grayscale),
+ Some(ref t) if t == "GRAYSCALE_ALPHA" => Some(ArbitraryTuplType::GrayscaleAlpha),
+ Some(ref t) if t == "RGB" => Some(ArbitraryTuplType::RGB),
+ Some(ref t) if t == "RGB_ALPHA" => Some(ArbitraryTuplType::RGBAlpha),
+ Some(other) => Some(ArbitraryTuplType::Custom(other)),
+ };
+
+ Ok(ArbitraryHeader {
+ height: h,
+ width: w,
+ depth: d,
+ maxval: m,
+ tupltype,
+ })
+ }
+}
+
+impl<R: Read> HeaderReader for BufReader<R> {}
+
+/// Wrapper struct around a `Cursor<Vec<u8>>`
+pub struct PnmReader<R>(Cursor<Vec<u8>>, PhantomData<R>);
+impl<R> Read for PnmReader<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> ImageDecoder<'a> for PnmDecoder<R> {
+ type Reader = PnmReader<R>;
+
+ fn dimensions(&self) -> (u32, u32) {
+ (self.header.width(), self.header.height())
+ }
+
+ fn color_type(&self) -> ColorType {
+ match self.tuple {
+ TupleType::PbmBit => ColorType::L8,
+ TupleType::BWBit => ColorType::L8,
+ TupleType::GrayU8 => ColorType::L8,
+ TupleType::GrayU16 => ColorType::L16,
+ TupleType::RGBU8 => ColorType::Rgb8,
+ TupleType::RGBU16 => ColorType::Rgb16,
+ }
+ }
+
+ fn original_color_type(&self) -> ExtendedColorType {
+ match self.tuple {
+ TupleType::PbmBit => ExtendedColorType::L1,
+ TupleType::BWBit => ExtendedColorType::L1,
+ TupleType::GrayU8 => ExtendedColorType::L8,
+ TupleType::GrayU16 => ExtendedColorType::L16,
+ TupleType::RGBU8 => ExtendedColorType::Rgb8,
+ TupleType::RGBU16 => ExtendedColorType::Rgb16,
+ }
+ }
+
+ fn into_reader(self) -> ImageResult<Self::Reader> {
+ Ok(PnmReader(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()));
+ buf.copy_from_slice(&match self.tuple {
+ TupleType::PbmBit => self.read_samples::<PbmBit>(1),
+ TupleType::BWBit => self.read_samples::<BWBit>(1),
+ TupleType::RGBU8 => self.read_samples::<U8>(3),
+ TupleType::RGBU16 => self.read_samples::<U16>(3),
+ TupleType::GrayU8 => self.read_samples::<U8>(1),
+ TupleType::GrayU16 => self.read_samples::<U16>(1),
+ }?);
+ Ok(())
+ }
+}
+
+fn err_input_is_too_short() -> ImageError {
+ return ImageError::FormatError(
+ "Not enough data was provided to the Decoder to decode the image".into()
+ )
+}
+
+impl<R: Read> PnmDecoder<R> {
+ fn read_samples<S: Sample>(&mut self, components: u32) -> ImageResult<Vec<u8>> {
+ match self.subtype().sample_encoding() {
+ SampleEncoding::Binary => {
+ let width = self.header.width();
+ let height = self.header.height();
+ let bytecount = S::bytelen(width, height, components)?;
+ let mut bytes = vec![];
+
+ self.reader
+ .by_ref()
+ // This conversion is potentially lossy but unlikely and in that case we error
+ // later anyways.
+ .take(bytecount as u64)
+ .read_to_end(&mut bytes)?;
+
+ if bytes.len() != bytecount {
+ return Err(err_input_is_too_short());
+ }
+
+ let samples = S::from_bytes(&bytes, width, height, components)?;
+ Ok(samples)
+ }
+ SampleEncoding::Ascii => {
+ let samples = self.read_ascii::<S>(components)?;
+ Ok(samples)
+ }
+ }
+ }
+
+ fn read_ascii<Basic: Sample>(&mut self, components: u32) -> ImageResult<Vec<u8>> {
+ Basic::from_ascii(&mut self.reader, self.header.width(), self.header.height(), components)
+ }
+
+ /// Get the pnm subtype, depending on the magic constant contained in the header
+ pub fn subtype(&self) -> PNMSubtype {
+ self.header.subtype()
+ }
+}
+
+fn read_separated_ascii<T: FromStr>(reader: &mut dyn Read) -> ImageResult<T>
+ where T::Err: Display
+{
+ let is_separator = |v: &u8| match *v {
+ b'\t' | b'\n' | b'\x0b' | b'\x0c' | b'\r' | b' ' => true,
+ _ => false,
+ };
+
+ let token = reader
+ .bytes()
+ .skip_while(|v| v.as_ref().ok().map(&is_separator).unwrap_or(false))
+ .take_while(|v| v.as_ref().ok().map(|c| !is_separator(c)).unwrap_or(false))
+ .collect::<Result<Vec<u8>, _>>()?;
+
+ if !token.is_ascii() {
+ return Err(ImageError::FormatError(
+ "Non ascii character where sample value was expected".to_string(),
+ ));
+ }
+
+ let string = str::from_utf8(&token)
+ // We checked the precondition ourselves a few lines before, `token.is_ascii()`.
+ .unwrap_or_else(|_| unreachable!("Only ascii characters should be decoded"));
+
+ string
+ .parse()
+ .map_err(|err| ImageError::FormatError(format!("Error parsing {} as a sample: {}", string, err)))
+}
+
+impl Sample for U8 {
+ fn bytelen(width: u32, height: u32, samples: u32) -> ImageResult<usize> {
+ Ok((width * height * samples) as usize)
+ }
+
+ fn from_bytes(
+ bytes: &[u8],
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ assert_eq!(bytes.len(), Self::bytelen(width, height, samples).unwrap());
+ Ok(bytes.to_vec())
+ }
+
+ fn from_ascii(
+ reader: &mut dyn Read,
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ (0..width*height*samples)
+ .map(|_| read_separated_ascii(reader))
+ .collect()
+ }
+}
+
+impl Sample for U16 {
+ fn bytelen(width: u32, height: u32, samples: u32) -> ImageResult<usize> {
+ Ok((width * height * samples * 2) as usize)
+ }
+
+ fn from_bytes(
+ bytes: &[u8],
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ assert_eq!(bytes.len(), Self::bytelen(width, height, samples).unwrap());
+
+ let mut buffer = bytes.to_vec();
+ for chunk in buffer.chunks_mut(2) {
+ let v = BigEndian::read_u16(chunk);
+ NativeEndian::write_u16(chunk, v);
+ }
+ Ok(buffer)
+ }
+
+ fn from_ascii(
+ reader: &mut dyn Read,
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ let mut buffer = vec![0; (width * height * samples * 2) as usize];
+ for i in 0..(width*height*samples) as usize {
+ let v = read_separated_ascii::<u16>(reader)?;
+ NativeEndian::write_u16(&mut buffer[2*i..][..2], v);
+ }
+ Ok(buffer)
+ }
+}
+
+// The image is encoded in rows of bits, high order bits first. Any bits beyond the row bits should
+// be ignored. Also, contrary to rgb, black pixels are encoded as a 1 while white is 0. This will
+// need to be reversed for the grayscale output.
+impl Sample for PbmBit {
+ fn bytelen(width: u32, height: u32, samples: u32) -> ImageResult<usize> {
+ let count = width * samples;
+ let linelen = (count / 8) + ((count % 8) != 0) as u32;
+ Ok((linelen * height) as usize)
+ }
+
+ fn from_bytes(
+ bytes: &[u8],
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ assert_eq!(bytes.len(), Self::bytelen(width, height, samples).unwrap());
+
+ let mut expanded = utils::expand_bits(1, width * samples, bytes);
+ for b in expanded.iter_mut() {
+ *b = !*b;
+ }
+ Ok(expanded)
+ }
+
+ fn from_ascii(
+ reader: &mut dyn Read,
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ let count = (width*height*samples) as usize;
+ let raw_samples = reader.bytes()
+ .filter_map(|ascii| match ascii {
+ Ok(b'0') => Some(Ok(1)),
+ Ok(b'1') => Some(Ok(0)),
+ Err(err) => Some(Err(ImageError::IoError(err))),
+ Ok(b'\t')
+ | Ok(b'\n')
+ | Ok(b'\x0b')
+ | Ok(b'\x0c')
+ | Ok(b'\r')
+ | Ok(b' ') => None,
+ Ok(c) => Some(Err(ImageError::FormatError(
+ format!("Unexpected character {} within sample raster", c),
+ ))),
+ })
+ .take(count)
+ .collect::<ImageResult<Vec<u8>>>()?;
+
+ if raw_samples.len() < count {
+ return Err(err_input_is_too_short())
+ }
+
+ Ok(raw_samples)
+ }
+}
+
+// Encoded just like a normal U8 but we check the values.
+impl Sample for BWBit {
+ fn bytelen(width: u32, height: u32, samples: u32) -> ImageResult<usize> {
+ U8::bytelen(width, height, samples)
+ }
+
+ fn from_bytes(
+ bytes: &[u8],
+ width: u32,
+ height: u32,
+ samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ assert_eq!(bytes.len(), Self::bytelen(width, height, samples).unwrap());
+
+ let values = U8::from_bytes(bytes, width, height, samples)?;
+ if let Some(val) = values.iter().find(|&val| *val > 1) {
+ return Err(ImageError::FormatError(
+ format!("Sample value {} outside of bounds", val),
+ ));
+ };
+ Ok(values)
+ }
+
+ fn from_ascii(
+ _reader: &mut dyn Read,
+ _width: u32,
+ _height: u32,
+ _samples: u32,
+ ) -> ImageResult<Vec<u8>> {
+ unreachable!("BW bits from anymaps are never encoded as ascii")
+ }
+}
+
+impl DecodableImageHeader for BitmapHeader {
+ fn tuple_type(&self) -> ImageResult<TupleType> {
+ Ok(TupleType::PbmBit)
+ }
+}
+
+impl DecodableImageHeader for GraymapHeader {
+ fn tuple_type(&self) -> ImageResult<TupleType> {
+ match self.maxwhite {
+ v if v <= 0xFF => Ok(TupleType::GrayU8),
+ v if v <= 0xFFFF => Ok(TupleType::GrayU16),
+ _ => Err(ImageError::FormatError(
+ "Image maxval is not less or equal to 65535".to_string(),
+ )),
+ }
+ }
+}
+
+impl DecodableImageHeader for PixmapHeader {
+ fn tuple_type(&self) -> ImageResult<TupleType> {
+ match self.maxval {
+ v if v <= 0xFF => Ok(TupleType::RGBU8),
+ v if v <= 0xFFFF => Ok(TupleType::RGBU16),
+ _ => Err(ImageError::FormatError(
+ "Image maxval is not less or equal to 65535".to_string(),
+ )),
+ }
+ }
+}
+
+impl DecodableImageHeader for ArbitraryHeader {
+ fn tuple_type(&self) -> ImageResult<TupleType> {
+ match self.tupltype {
+ None if self.depth == 1 => Ok(TupleType::GrayU8),
+ None if self.depth == 2 => Err(ImageError::UnsupportedColor(ExtendedColorType::La8)),
+ None if self.depth == 3 => Ok(TupleType::RGBU8),
+ None if self.depth == 4 => Err(ImageError::UnsupportedColor(ExtendedColorType::Rgba8)),
+
+ Some(ArbitraryTuplType::BlackAndWhite) if self.maxval == 1 && self.depth == 1 => {
+ Ok(TupleType::BWBit)
+ }
+ Some(ArbitraryTuplType::BlackAndWhite) => Err(ImageError::FormatError(
+ "Invalid depth or maxval for tuple type BLACKANDWHITE".to_string(),
+ )),
+
+ Some(ArbitraryTuplType::Grayscale) if self.depth == 1 && self.maxval <= 0xFF => {
+ Ok(TupleType::GrayU8)
+ }
+ Some(ArbitraryTuplType::Grayscale) if self.depth <= 1 && self.maxval <= 0xFFFF => {
+ Ok(TupleType::GrayU16)
+ }
+ Some(ArbitraryTuplType::Grayscale) => Err(ImageError::FormatError(
+ "Invalid depth or maxval for tuple type GRAYSCALE".to_string(),
+ )),
+
+ Some(ArbitraryTuplType::RGB) if self.depth == 3 && self.maxval <= 0xFF => {
+ Ok(TupleType::RGBU8)
+ }
+ Some(ArbitraryTuplType::RGB) if self.depth == 3 && self.maxval <= 0xFFFF => {
+ Ok(TupleType::RGBU16)
+ }
+ Some(ArbitraryTuplType::RGB) => Err(ImageError::FormatError(
+ "Invalid depth for tuple type RGB".to_string(),
+ )),
+
+ Some(ArbitraryTuplType::BlackAndWhiteAlpha) => Err(ImageError::FormatError(
+ "Unsupported color type: BlackAndWhiteAlpha".to_string()
+ )),
+ Some(ArbitraryTuplType::GrayscaleAlpha) => {
+ Err(ImageError::UnsupportedColor(ExtendedColorType::La8))
+ }
+ Some(ArbitraryTuplType::RGBAlpha) => {
+ Err(ImageError::UnsupportedColor(ExtendedColorType::Rgba8))
+ }
+ _ => Err(ImageError::FormatError(
+ "Tuple type not recognized".to_string(),
+ )),
+ }
+ }
+}
+#[cfg(test)]
+mod tests {
+ use super::*;
+ /// Tests reading of a valid blackandwhite pam
+ #[test]
+ fn pam_blackandwhite() {
+ let pamdata = b"P7
+WIDTH 4
+HEIGHT 4
+DEPTH 1
+MAXVAL 1
+TUPLTYPE BLACKANDWHITE
+# Comment line
+ENDHDR
+\x01\x00\x00\x01\x01\x00\x00\x01\x01\x00\x00\x01\x01\x00\x00\x01";
+ let decoder = PnmDecoder::new(&pamdata[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.original_color_type(), ExtendedColorType::L1);
+ assert_eq!(decoder.dimensions(), (4, 4));
+ assert_eq!(decoder.subtype(), PNMSubtype::ArbitraryMap);
+
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(
+ image,
+ vec![0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00,
+ 0x00, 0x01]
+ );
+ match PnmDecoder::new(&pamdata[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Arbitrary(ArbitraryHeader {
+ width: 4,
+ height: 4,
+ maxval: 1,
+ depth: 1,
+ tupltype: Some(ArbitraryTuplType::BlackAndWhite),
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ /// Tests reading of a valid grayscale pam
+ #[test]
+ fn pam_grayscale() {
+ let pamdata = b"P7
+WIDTH 4
+HEIGHT 4
+DEPTH 1
+MAXVAL 255
+TUPLTYPE GRAYSCALE
+# Comment line
+ENDHDR
+\xde\xad\xbe\xef\xde\xad\xbe\xef\xde\xad\xbe\xef\xde\xad\xbe\xef";
+ let decoder = PnmDecoder::new(&pamdata[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.dimensions(), (4, 4));
+ assert_eq!(decoder.subtype(), PNMSubtype::ArbitraryMap);
+
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(
+ image,
+ vec![0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef, 0xde, 0xad,
+ 0xbe, 0xef]
+ );
+ match PnmDecoder::new(&pamdata[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Arbitrary(ArbitraryHeader {
+ width: 4,
+ height: 4,
+ depth: 1,
+ maxval: 255,
+ tupltype: Some(ArbitraryTuplType::Grayscale),
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ /// Tests reading of a valid rgb pam
+ #[test]
+ fn pam_rgb() {
+ let pamdata = b"P7
+# Comment line
+MAXVAL 255
+TUPLTYPE RGB
+DEPTH 3
+WIDTH 2
+HEIGHT 2
+ENDHDR
+\xde\xad\xbe\xef\xde\xad\xbe\xef\xde\xad\xbe\xef";
+ let decoder = PnmDecoder::new(&pamdata[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::Rgb8);
+ assert_eq!(decoder.dimensions(), (2, 2));
+ assert_eq!(decoder.subtype(), PNMSubtype::ArbitraryMap);
+
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image,
+ vec![0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef]);
+ match PnmDecoder::new(&pamdata[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Arbitrary(ArbitraryHeader {
+ maxval: 255,
+ tupltype: Some(ArbitraryTuplType::RGB),
+ depth: 3,
+ width: 2,
+ height: 2,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ #[test]
+ fn pbm_binary() {
+ // The data contains two rows of the image (each line is padded to the full byte). For
+ // comments on its format, see documentation of `impl SampleType for PbmBit`.
+ let pbmbinary = [&b"P4 6 2\n"[..], &[0b01101100 as u8, 0b10110111]].concat();
+ let decoder = PnmDecoder::new(&pbmbinary[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.original_color_type(), ExtendedColorType::L1);
+ assert_eq!(decoder.dimensions(), (6, 2));
+ assert_eq!(
+ decoder.subtype(),
+ PNMSubtype::Bitmap(SampleEncoding::Binary)
+ );
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image, vec![255, 0, 0, 255, 0, 0, 0, 255, 0, 0, 255, 0]);
+ match PnmDecoder::new(&pbmbinary[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Bitmap(BitmapHeader {
+ encoding: SampleEncoding::Binary,
+ width: 6,
+ height: 2,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ /// A previous inifite loop.
+ #[test]
+ fn pbm_binary_ascii_termination() {
+ use std::io::{Cursor, Error, ErrorKind, Read, Result};
+ struct FailRead(Cursor<&'static [u8]>);
+
+ impl Read for FailRead {
+ fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+ match self.0.read(buf) {
+ Ok(n) if n > 0 => Ok(n),
+ _ => Err(Error::new(
+ ErrorKind::BrokenPipe,
+ "Simulated broken pipe error"
+ )),
+ }
+ }
+ }
+
+ let pbmbinary = FailRead(Cursor::new(b"P1 1 1\n"));
+
+ let decoder = PnmDecoder::new(pbmbinary).unwrap();
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).expect_err("Image is malformed");
+ }
+
+ #[test]
+ fn pbm_ascii() {
+ // The data contains two rows of the image (each line is padded to the full byte). For
+ // comments on its format, see documentation of `impl SampleType for PbmBit`. Tests all
+ // whitespace characters that should be allowed (the 6 characters according to POSIX).
+ let pbmbinary = b"P1 6 2\n 0 1 1 0 1 1\n1 0 1 1 0\t\n\x0b\x0c\r1";
+ let decoder = PnmDecoder::new(&pbmbinary[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.original_color_type(), ExtendedColorType::L1);
+ assert_eq!(decoder.dimensions(), (6, 2));
+ assert_eq!(decoder.subtype(), PNMSubtype::Bitmap(SampleEncoding::Ascii));
+
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image, vec![1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0]);
+ match PnmDecoder::new(&pbmbinary[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Bitmap(BitmapHeader {
+ encoding: SampleEncoding::Ascii,
+ width: 6,
+ height: 2,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ #[test]
+ fn pbm_ascii_nospace() {
+ // The data contains two rows of the image (each line is padded to the full byte). Notably,
+ // it is completely within specification for the ascii data not to contain separating
+ // whitespace for the pbm format or any mix.
+ let pbmbinary = b"P1 6 2\n011011101101";
+ let decoder = PnmDecoder::new(&pbmbinary[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.original_color_type(), ExtendedColorType::L1);
+ assert_eq!(decoder.dimensions(), (6, 2));
+ assert_eq!(decoder.subtype(), PNMSubtype::Bitmap(SampleEncoding::Ascii));
+
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image, vec![1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0]);
+ match PnmDecoder::new(&pbmbinary[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Bitmap(BitmapHeader {
+ encoding: SampleEncoding::Ascii,
+ width: 6,
+ height: 2,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ #[test]
+ fn pgm_binary() {
+ // The data contains two rows of the image (each line is padded to the full byte). For
+ // comments on its format, see documentation of `impl SampleType for PbmBit`.
+ let elements = (0..16).collect::<Vec<_>>();
+ let pbmbinary = [&b"P5 4 4 255\n"[..], &elements].concat();
+ let decoder = PnmDecoder::new(&pbmbinary[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.dimensions(), (4, 4));
+ assert_eq!(
+ decoder.subtype(),
+ PNMSubtype::Graymap(SampleEncoding::Binary)
+ );
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image, elements);
+ match PnmDecoder::new(&pbmbinary[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Graymap(GraymapHeader {
+ encoding: SampleEncoding::Binary,
+ width: 4,
+ height: 4,
+ maxwhite: 255,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+
+ #[test]
+ fn pgm_ascii() {
+ // The data contains two rows of the image (each line is padded to the full byte). For
+ // comments on its format, see documentation of `impl SampleType for PbmBit`.
+ let pbmbinary = b"P2 4 4 255\n 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15";
+ let decoder = PnmDecoder::new(&pbmbinary[..]).unwrap();
+ assert_eq!(decoder.color_type(), ColorType::L8);
+ assert_eq!(decoder.dimensions(), (4, 4));
+ assert_eq!(
+ decoder.subtype(),
+ PNMSubtype::Graymap(SampleEncoding::Ascii)
+ );
+ let mut image = vec![0; decoder.total_bytes() as usize];
+ decoder.read_image(&mut image).unwrap();
+ assert_eq!(image, (0..16).collect::<Vec<_>>());
+ match PnmDecoder::new(&pbmbinary[..]).unwrap().into_inner() {
+ (
+ _,
+ PNMHeader {
+ decoded:
+ HeaderRecord::Graymap(GraymapHeader {
+ encoding: SampleEncoding::Ascii,
+ width: 4,
+ height: 4,
+ maxwhite: 255,
+ }),
+ encoded: _,
+ },
+ ) => (),
+ _ => panic!("Decoded header is incorrect"),
+ }
+ }
+}