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-rw-r--r--vendor/qoi/src/decode.rs396
1 files changed, 0 insertions, 396 deletions
diff --git a/vendor/qoi/src/decode.rs b/vendor/qoi/src/decode.rs
deleted file mode 100644
index 019dac2..0000000
--- a/vendor/qoi/src/decode.rs
+++ /dev/null
@@ -1,396 +0,0 @@
-#[cfg(any(feature = "std", feature = "alloc"))]
-use alloc::{vec, vec::Vec};
-#[cfg(feature = "std")]
-use std::io::Read;
-
-// TODO: can be removed once https://github.com/rust-lang/rust/issues/74985 is stable
-use bytemuck::{cast_slice_mut, Pod};
-
-use crate::consts::{
- QOI_HEADER_SIZE, QOI_OP_DIFF, QOI_OP_INDEX, QOI_OP_LUMA, QOI_OP_RGB, QOI_OP_RGBA, QOI_OP_RUN,
- QOI_PADDING, QOI_PADDING_SIZE,
-};
-use crate::error::{Error, Result};
-use crate::header::Header;
-use crate::pixel::{Pixel, SupportedChannels};
-use crate::types::Channels;
-use crate::utils::{cold, unlikely};
-
-const QOI_OP_INDEX_END: u8 = QOI_OP_INDEX | 0x3f;
-const QOI_OP_RUN_END: u8 = QOI_OP_RUN | 0x3d; // <- note, 0x3d (not 0x3f)
-const QOI_OP_DIFF_END: u8 = QOI_OP_DIFF | 0x3f;
-const QOI_OP_LUMA_END: u8 = QOI_OP_LUMA | 0x3f;
-
-#[inline]
-fn decode_impl_slice<const N: usize, const RGBA: bool>(data: &[u8], out: &mut [u8]) -> Result<usize>
-where
- Pixel<N>: SupportedChannels,
- [u8; N]: Pod,
-{
- let mut pixels = cast_slice_mut::<_, [u8; N]>(out);
- let data_len = data.len();
- let mut data = data;
-
- let mut index = [Pixel::<4>::new(); 256];
- let mut px = Pixel::<N>::new().with_a(0xff);
- let mut px_rgba: Pixel<4>;
-
- while let [px_out, ptail @ ..] = pixels {
- pixels = ptail;
- match data {
- [b1 @ QOI_OP_INDEX..=QOI_OP_INDEX_END, dtail @ ..] => {
- px_rgba = index[*b1 as usize];
- px.update(px_rgba);
- *px_out = px.into();
- data = dtail;
- continue;
- }
- [QOI_OP_RGB, r, g, b, dtail @ ..] => {
- px.update_rgb(*r, *g, *b);
- data = dtail;
- }
- [QOI_OP_RGBA, r, g, b, a, dtail @ ..] if RGBA => {
- px.update_rgba(*r, *g, *b, *a);
- data = dtail;
- }
- [b1 @ QOI_OP_RUN..=QOI_OP_RUN_END, dtail @ ..] => {
- *px_out = px.into();
- let run = ((b1 & 0x3f) as usize).min(pixels.len());
- let (phead, ptail) = pixels.split_at_mut(run); // can't panic
- phead.fill(px.into());
- pixels = ptail;
- data = dtail;
- continue;
- }
- [b1 @ QOI_OP_DIFF..=QOI_OP_DIFF_END, dtail @ ..] => {
- px.update_diff(*b1);
- data = dtail;
- }
- [b1 @ QOI_OP_LUMA..=QOI_OP_LUMA_END, b2, dtail @ ..] => {
- px.update_luma(*b1, *b2);
- data = dtail;
- }
- _ => {
- cold();
- if unlikely(data.len() < QOI_PADDING_SIZE) {
- return Err(Error::UnexpectedBufferEnd);
- }
- }
- }
-
- px_rgba = px.as_rgba(0xff);
- index[px_rgba.hash_index() as usize] = px_rgba;
- *px_out = px.into();
- }
-
- if unlikely(data.len() < QOI_PADDING_SIZE) {
- return Err(Error::UnexpectedBufferEnd);
- } else if unlikely(data[..QOI_PADDING_SIZE] != QOI_PADDING) {
- return Err(Error::InvalidPadding);
- }
-
- Ok(data_len.saturating_sub(data.len()).saturating_sub(QOI_PADDING_SIZE))
-}
-
-#[inline]
-fn decode_impl_slice_all(
- data: &[u8], out: &mut [u8], channels: u8, src_channels: u8,
-) -> Result<usize> {
- match (channels, src_channels) {
- (3, 3) => decode_impl_slice::<3, false>(data, out),
- (3, 4) => decode_impl_slice::<3, true>(data, out),
- (4, 3) => decode_impl_slice::<4, false>(data, out),
- (4, 4) => decode_impl_slice::<4, true>(data, out),
- _ => {
- cold();
- Err(Error::InvalidChannels { channels })
- }
- }
-}
-
-/// Decode the image into a pre-allocated buffer.
-///
-/// Note: the resulting number of channels will match the header. In order to change
-/// the number of channels, use [`Decoder::with_channels`].
-#[inline]
-pub fn decode_to_buf(buf: impl AsMut<[u8]>, data: impl AsRef<[u8]>) -> Result<Header> {
- let mut decoder = Decoder::new(&data)?;
- decoder.decode_to_buf(buf)?;
- Ok(*decoder.header())
-}
-
-/// Decode the image into a newly allocated vector.
-///
-/// Note: the resulting number of channels will match the header. In order to change
-/// the number of channels, use [`Decoder::with_channels`].
-#[cfg(any(feature = "std", feature = "alloc"))]
-#[inline]
-pub fn decode_to_vec(data: impl AsRef<[u8]>) -> Result<(Header, Vec<u8>)> {
- let mut decoder = Decoder::new(&data)?;
- let out = decoder.decode_to_vec()?;
- Ok((*decoder.header(), out))
-}
-
-/// Decode the image header from a slice of bytes.
-#[inline]
-pub fn decode_header(data: impl AsRef<[u8]>) -> Result<Header> {
- Header::decode(data)
-}
-
-#[cfg(any(feature = "std"))]
-#[inline]
-fn decode_impl_stream<R: Read, const N: usize, const RGBA: bool>(
- data: &mut R, out: &mut [u8],
-) -> Result<()>
-where
- Pixel<N>: SupportedChannels,
- [u8; N]: Pod,
-{
- let mut pixels = cast_slice_mut::<_, [u8; N]>(out);
-
- let mut index = [Pixel::<N>::new(); 256];
- let mut px = Pixel::<N>::new().with_a(0xff);
-
- while let [px_out, ptail @ ..] = pixels {
- pixels = ptail;
- let mut p = [0];
- data.read_exact(&mut p)?;
- let [b1] = p;
- match b1 {
- QOI_OP_INDEX..=QOI_OP_INDEX_END => {
- px = index[b1 as usize];
- *px_out = px.into();
- continue;
- }
- QOI_OP_RGB => {
- let mut p = [0; 3];
- data.read_exact(&mut p)?;
- px.update_rgb(p[0], p[1], p[2]);
- }
- QOI_OP_RGBA if RGBA => {
- let mut p = [0; 4];
- data.read_exact(&mut p)?;
- px.update_rgba(p[0], p[1], p[2], p[3]);
- }
- QOI_OP_RUN..=QOI_OP_RUN_END => {
- *px_out = px.into();
- let run = ((b1 & 0x3f) as usize).min(pixels.len());
- let (phead, ptail) = pixels.split_at_mut(run); // can't panic
- phead.fill(px.into());
- pixels = ptail;
- continue;
- }
- QOI_OP_DIFF..=QOI_OP_DIFF_END => {
- px.update_diff(b1);
- }
- QOI_OP_LUMA..=QOI_OP_LUMA_END => {
- let mut p = [0];
- data.read_exact(&mut p)?;
- let [b2] = p;
- px.update_luma(b1, b2);
- }
- _ => {
- cold();
- }
- }
-
- index[px.hash_index() as usize] = px;
- *px_out = px.into();
- }
-
- let mut p = [0_u8; QOI_PADDING_SIZE];
- data.read_exact(&mut p)?;
- if unlikely(p != QOI_PADDING) {
- return Err(Error::InvalidPadding);
- }
-
- Ok(())
-}
-
-#[cfg(feature = "std")]
-#[inline]
-fn decode_impl_stream_all<R: Read>(
- data: &mut R, out: &mut [u8], channels: u8, src_channels: u8,
-) -> Result<()> {
- match (channels, src_channels) {
- (3, 3) => decode_impl_stream::<_, 3, false>(data, out),
- (3, 4) => decode_impl_stream::<_, 3, true>(data, out),
- (4, 3) => decode_impl_stream::<_, 4, false>(data, out),
- (4, 4) => decode_impl_stream::<_, 4, true>(data, out),
- _ => {
- cold();
- Err(Error::InvalidChannels { channels })
- }
- }
-}
-
-#[doc(hidden)]
-pub trait Reader: Sized {
- fn decode_header(&mut self) -> Result<Header>;
- fn decode_image(&mut self, out: &mut [u8], channels: u8, src_channels: u8) -> Result<()>;
-}
-
-pub struct Bytes<'a>(&'a [u8]);
-
-impl<'a> Bytes<'a> {
- #[inline]
- pub const fn new(buf: &'a [u8]) -> Self {
- Self(buf)
- }
-
- #[inline]
- pub const fn as_slice(&self) -> &[u8] {
- self.0
- }
-}
-
-impl<'a> Reader for Bytes<'a> {
- #[inline]
- fn decode_header(&mut self) -> Result<Header> {
- let header = Header::decode(self.0)?;
- self.0 = &self.0[QOI_HEADER_SIZE..]; // can't panic
- Ok(header)
- }
-
- #[inline]
- fn decode_image(&mut self, out: &mut [u8], channels: u8, src_channels: u8) -> Result<()> {
- let n_read = decode_impl_slice_all(self.0, out, channels, src_channels)?;
- self.0 = &self.0[n_read..];
- Ok(())
- }
-}
-
-#[cfg(feature = "std")]
-impl<R: Read> Reader for R {
- #[inline]
- fn decode_header(&mut self) -> Result<Header> {
- let mut b = [0; QOI_HEADER_SIZE];
- self.read_exact(&mut b)?;
- Header::decode(b)
- }
-
- #[inline]
- fn decode_image(&mut self, out: &mut [u8], channels: u8, src_channels: u8) -> Result<()> {
- decode_impl_stream_all(self, out, channels, src_channels)
- }
-}
-
-/// Decode QOI images from slices or from streams.
-#[derive(Clone)]
-pub struct Decoder<R> {
- reader: R,
- header: Header,
- channels: Channels,
-}
-
-impl<'a> Decoder<Bytes<'a>> {
- /// Creates a new decoder from a slice of bytes.
- ///
- /// The header will be decoded immediately upon construction.
- ///
- /// Note: this provides the most efficient decoding, but requires the source data to
- /// be loaded in memory in order to decode it. In order to decode from a generic
- /// stream, use [`Decoder::from_stream`] instead.
- #[inline]
- pub fn new(data: &'a (impl AsRef<[u8]> + ?Sized)) -> Result<Self> {
- Self::new_impl(Bytes::new(data.as_ref()))
- }
-
- /// Returns the undecoded tail of the input slice of bytes.
- #[inline]
- pub const fn data(&self) -> &[u8] {
- self.reader.as_slice()
- }
-}
-
-#[cfg(feature = "std")]
-impl<R: Read> Decoder<R> {
- /// Creates a new decoder from a generic reader that implements [`Read`](std::io::Read).
- ///
- /// The header will be decoded immediately upon construction.
- ///
- /// Note: while it's possible to pass a `&[u8]` slice here since it implements `Read`, it
- /// would be more efficient to use a specialized constructor instead: [`Decoder::new`].
- #[inline]
- pub fn from_stream(reader: R) -> Result<Self> {
- Self::new_impl(reader)
- }
-
- /// Returns an immutable reference to the underlying reader.
- #[inline]
- pub const fn reader(&self) -> &R {
- &self.reader
- }
-
- /// Consumes the decoder and returns the underlying reader back.
- #[inline]
- #[allow(clippy::missing_const_for_fn)]
- pub fn into_reader(self) -> R {
- self.reader
- }
-}
-
-impl<R: Reader> Decoder<R> {
- #[inline]
- fn new_impl(mut reader: R) -> Result<Self> {
- let header = reader.decode_header()?;
- Ok(Self { reader, header, channels: header.channels })
- }
-
- /// Returns a new decoder with modified number of channels.
- ///
- /// By default, the number of channels in the decoded image will be equal
- /// to whatever is specified in the header. However, it is also possible
- /// to decode RGB into RGBA (in which case the alpha channel will be set
- /// to 255), and vice versa (in which case the alpha channel will be ignored).
- #[inline]
- pub const fn with_channels(mut self, channels: Channels) -> Self {
- self.channels = channels;
- self
- }
-
- /// Returns the number of channels in the decoded image.
- ///
- /// Note: this may differ from the number of channels specified in the header.
- #[inline]
- pub const fn channels(&self) -> Channels {
- self.channels
- }
-
- /// Returns the decoded image header.
- #[inline]
- pub const fn header(&self) -> &Header {
- &self.header
- }
-
- /// The number of bytes the decoded image will take.
- ///
- /// Can be used to pre-allocate the buffer to decode the image into.
- #[inline]
- pub const fn required_buf_len(&self) -> usize {
- self.header.n_pixels().saturating_mul(self.channels.as_u8() as usize)
- }
-
- /// Decodes the image to a pre-allocated buffer and returns the number of bytes written.
- ///
- /// The minimum size of the buffer can be found via [`Decoder::required_buf_len`].
- #[inline]
- pub fn decode_to_buf(&mut self, mut buf: impl AsMut<[u8]>) -> Result<usize> {
- let buf = buf.as_mut();
- let size = self.required_buf_len();
- if unlikely(buf.len() < size) {
- return Err(Error::OutputBufferTooSmall { size: buf.len(), required: size });
- }
- self.reader.decode_image(buf, self.channels.as_u8(), self.header.channels.as_u8())?;
- Ok(size)
- }
-
- /// Decodes the image into a newly allocated vector of bytes and returns it.
- #[cfg(any(feature = "std", feature = "alloc"))]
- #[inline]
- pub fn decode_to_vec(&mut self) -> Result<Vec<u8>> {
- let mut out = vec![0; self.header.n_pixels() * self.channels.as_u8() as usize];
- let _ = self.decode_to_buf(&mut out)?;
- Ok(out)
- }
-}
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