Initial vendor packages

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

1 files changed, 592 insertions, 0 deletions

diff --git a/vendor/image/src/codecs/openexr.rs b/vendor/image/src/codecs/openexr.rs
new file mode 100644
index 0000000..52d6ba9
--- /dev/null
+++ b/vendor/image/src/codecs/openexr.rs
@@ -0,0 +1,592 @@
+//! Decoding of OpenEXR (.exr) Images
+//!
+//! OpenEXR is an image format that is widely used, especially in VFX,
+//! because it supports lossless and lossy compression for float data.
+//!
+//! This decoder only supports RGB and RGBA images.
+//! If an image does not contain alpha information,
+//! it is defaulted to `1.0` (no transparency).
+//!
+//! # Related Links
+//! * <https://www.openexr.com/documentation.html> - The OpenEXR reference.
+//!
+//!
+//! Current limitations (July 2021):
+//!     - only pixel type `Rgba32F` and `Rgba16F` are supported
+//!     - only non-deep rgb/rgba files supported, no conversion from/to YCbCr or similar
+//!     - only the first non-deep rgb layer is used
+//!     - only the largest mip map level is used
+//!     - pixels outside display window are lost
+//!     - meta data is lost
+//!     - dwaa/dwab compressed images not supported yet by the exr library
+//!     - (chroma) subsampling not supported yet by the exr library
+use exr::prelude::*;
+
+use crate::error::{DecodingError, EncodingError, ImageFormatHint};
+use crate::image::decoder_to_vec;
+use crate::{
+    ColorType, ExtendedColorType, ImageDecoder, ImageEncoder, ImageError, ImageFormat, ImageResult,
+    Progress,
+};
+use std::convert::TryInto;
+use std::io::{Cursor, Read, Seek, Write};
+
+/// An OpenEXR decoder. Immediately reads the meta data from the file.
+#[derive(Debug)]
+pub struct OpenExrDecoder<R> {
+    exr_reader: exr::block::reader::Reader<R>,
+
+    // select a header that is rgb and not deep
+    header_index: usize,
+
+    // decode either rgb or rgba.
+    // can be specified to include or discard alpha channels.
+    // if none, the alpha channel will only be allocated where the file contains data for it.
+    alpha_preference: Option<bool>,
+
+    alpha_present_in_file: bool,
+}
+
+impl<R: Read + Seek> OpenExrDecoder<R> {
+    /// Create a decoder. Consumes the first few bytes of the source to extract image dimensions.
+    /// Assumes the reader is buffered. In most cases,
+    /// you should wrap your reader in a `BufReader` for best performance.
+    /// Loads an alpha channel if the file has alpha samples.
+    /// Use `with_alpha_preference` if you want to load or not load alpha unconditionally.
+    pub fn new(source: R) -> ImageResult<Self> {
+        Self::with_alpha_preference(source, None)
+    }
+
+    /// Create a decoder. Consumes the first few bytes of the source to extract image dimensions.
+    /// Assumes the reader is buffered. In most cases,
+    /// you should wrap your reader in a `BufReader` for best performance.
+    /// If alpha preference is specified, an alpha channel will
+    /// always be present or always be not present in the returned image.
+    /// If alpha preference is none, the alpha channel will only be returned if it is found in the file.
+    pub fn with_alpha_preference(source: R, alpha_preference: Option<bool>) -> ImageResult<Self> {
+        // read meta data, then wait for further instructions, keeping the file open and ready
+        let exr_reader = exr::block::read(source, false).map_err(to_image_err)?;
+
+        let header_index = exr_reader
+            .headers()
+            .iter()
+            .position(|header| {
+                // check if r/g/b exists in the channels
+                let has_rgb = ["R", "G", "B"]
+                    .iter()
+                    .all(|&required|  // alpha will be optional
+                    header.channels.find_index_of_channel(&Text::from(required)).is_some());
+
+                // we currently dont support deep images, or images with other color spaces than rgb
+                !header.deep && has_rgb
+            })
+            .ok_or_else(|| {
+                ImageError::Decoding(DecodingError::new(
+                    ImageFormatHint::Exact(ImageFormat::OpenExr),
+                    "image does not contain non-deep rgb channels",
+                ))
+            })?;
+
+        let has_alpha = exr_reader.headers()[header_index]
+            .channels
+            .find_index_of_channel(&Text::from("A"))
+            .is_some();
+
+        Ok(Self {
+            alpha_preference,
+            exr_reader,
+            header_index,
+            alpha_present_in_file: has_alpha,
+        })
+    }
+
+    // does not leak exrs-specific meta data into public api, just does it for this module
+    fn selected_exr_header(&self) -> &exr::meta::header::Header {
+        &self.exr_reader.meta_data().headers[self.header_index]
+    }
+}
+
+impl<'a, R: 'a + Read + Seek> ImageDecoder<'a> for OpenExrDecoder<R> {
+    type Reader = Cursor<Vec<u8>>;
+
+    fn dimensions(&self) -> (u32, u32) {
+        let size = self
+            .selected_exr_header()
+            .shared_attributes
+            .display_window
+            .size;
+        (size.width() as u32, size.height() as u32)
+    }
+
+    fn color_type(&self) -> ColorType {
+        let returns_alpha = self.alpha_preference.unwrap_or(self.alpha_present_in_file);
+        if returns_alpha {
+            ColorType::Rgba32F
+        } else {
+            ColorType::Rgb32F
+        }
+    }
+
+    fn original_color_type(&self) -> ExtendedColorType {
+        if self.alpha_present_in_file {
+            ExtendedColorType::Rgba32F
+        } else {
+            ExtendedColorType::Rgb32F
+        }
+    }
+
+    /// Use `read_image` instead if possible,
+    /// as this method creates a whole new buffer just to contain the entire image.
+    fn into_reader(self) -> ImageResult<Self::Reader> {
+        Ok(Cursor::new(decoder_to_vec(self)?))
+    }
+
+    fn scanline_bytes(&self) -> u64 {
+        // we cannot always read individual scan lines for every file,
+        // as the tiles or lines in the file could be in random or reversed order.
+        // therefore we currently read all lines at once
+        // Todo: optimize for specific exr.line_order?
+        self.total_bytes()
+    }
+
+    // reads with or without alpha, depending on `self.alpha_preference` and `self.alpha_present_in_file`
+    fn read_image_with_progress<F: Fn(Progress)>(
+        self,
+        unaligned_bytes: &mut [u8],
+        progress_callback: F,
+    ) -> ImageResult<()> {
+        let blocks_in_header = self.selected_exr_header().chunk_count as u64;
+        let channel_count = self.color_type().channel_count() as usize;
+
+        let display_window = self.selected_exr_header().shared_attributes.display_window;
+        let data_window_offset =
+            self.selected_exr_header().own_attributes.layer_position - display_window.position;
+
+        {
+            // check whether the buffer is large enough for the dimensions of the file
+            let (width, height) = self.dimensions();
+            let bytes_per_pixel = self.color_type().bytes_per_pixel() as usize;
+            let expected_byte_count = (width as usize)
+                .checked_mul(height as usize)
+                .and_then(|size| size.checked_mul(bytes_per_pixel));
+
+            // if the width and height does not match the length of the bytes, the arguments are invalid
+            let has_invalid_size_or_overflowed = expected_byte_count
+                .map(|expected_byte_count| unaligned_bytes.len() != expected_byte_count)
+                // otherwise, size calculation overflowed, is bigger than memory,
+                // therefore data is too small, so it is invalid.
+                .unwrap_or(true);
+
+            if has_invalid_size_or_overflowed {
+                panic!("byte buffer not large enough for the specified dimensions and f32 pixels");
+            }
+        }
+
+        let result = read()
+            .no_deep_data()
+            .largest_resolution_level()
+            .rgba_channels(
+                move |_size, _channels| vec![0_f32; display_window.size.area() * channel_count],
+                move |buffer, index_in_data_window, (r, g, b, a_or_1): (f32, f32, f32, f32)| {
+                    let index_in_display_window =
+                        index_in_data_window.to_i32() + data_window_offset;
+
+                    // only keep pixels inside the data window
+                    // TODO filter chunks based on this
+                    if index_in_display_window.x() >= 0
+                        && index_in_display_window.y() >= 0
+                        && index_in_display_window.x() < display_window.size.width() as i32
+                        && index_in_display_window.y() < display_window.size.height() as i32
+                    {
+                        let index_in_display_window =
+                            index_in_display_window.to_usize("index bug").unwrap();
+                        let first_f32_index =
+                            index_in_display_window.flat_index_for_size(display_window.size);
+
+                        buffer[first_f32_index * channel_count
+                            ..(first_f32_index + 1) * channel_count]
+                            .copy_from_slice(&[r, g, b, a_or_1][0..channel_count]);
+
+                        // TODO white point chromaticities + srgb/linear conversion?
+                    }
+                },
+            )
+            .first_valid_layer() // TODO select exact layer by self.header_index?
+            .all_attributes()
+            .on_progress(|progress| {
+                progress_callback(
+                    Progress::new(
+                        (progress * blocks_in_header as f64) as u64,
+                        blocks_in_header,
+                    ), // TODO precision errors?
+                );
+            })
+            .from_chunks(self.exr_reader)
+            .map_err(to_image_err)?;
+
+        // TODO this copy is strictly not necessary, but the exr api is a little too simple for reading into a borrowed target slice
+
+        // this cast is safe and works with any alignment, as bytes are copied, and not f32 values.
+        // note: buffer slice length is checked in the beginning of this function and will be correct at this point
+        unaligned_bytes.copy_from_slice(bytemuck::cast_slice(
+            result.layer_data.channel_data.pixels.as_slice(),
+        ));
+        Ok(())
+    }
+}
+
+/// Write a raw byte buffer of pixels,
+/// returning an Error if it has an invalid length.
+///
+/// Assumes the writer is buffered. In most cases,
+/// you should wrap your writer in a `BufWriter` for best performance.
+// private. access via `OpenExrEncoder`
+fn write_buffer(
+    mut buffered_write: impl Write + Seek,
+    unaligned_bytes: &[u8],
+    width: u32,
+    height: u32,
+    color_type: ColorType,
+) -> ImageResult<()> {
+    let width = width as usize;
+    let height = height as usize;
+
+    {
+        // check whether the buffer is large enough for the specified dimensions
+        let expected_byte_count = width
+            .checked_mul(height)
+            .and_then(|size| size.checked_mul(color_type.bytes_per_pixel() as usize));
+
+        // if the width and height does not match the length of the bytes, the arguments are invalid
+        let has_invalid_size_or_overflowed = expected_byte_count
+            .map(|expected_byte_count| unaligned_bytes.len() < expected_byte_count)
+            // otherwise, size calculation overflowed, is bigger than memory,
+            // therefore data is too small, so it is invalid.
+            .unwrap_or(true);
+
+        if has_invalid_size_or_overflowed {
+            return Err(ImageError::Encoding(EncodingError::new(
+                ImageFormatHint::Exact(ImageFormat::OpenExr),
+                "byte buffer not large enough for the specified dimensions and f32 pixels",
+            )));
+        }
+    }
+
+    // bytes might be unaligned so we cannot cast the whole thing, instead lookup each f32 individually
+    let lookup_f32 = move |f32_index: usize| {
+        let unaligned_f32_bytes_slice = &unaligned_bytes[f32_index * 4..(f32_index + 1) * 4];
+        let f32_bytes_array = unaligned_f32_bytes_slice
+            .try_into()
+            .expect("indexing error");
+        f32::from_ne_bytes(f32_bytes_array)
+    };
+
+    match color_type {
+        ColorType::Rgb32F => {
+            exr::prelude::Image // TODO compression method zip??
+                ::from_channels(
+                (width, height),
+                SpecificChannels::rgb(|pixel: Vec2<usize>| {
+                    let pixel_index = 3 * pixel.flat_index_for_size(Vec2(width, height));
+                    (
+                        lookup_f32(pixel_index),
+                        lookup_f32(pixel_index + 1),
+                        lookup_f32(pixel_index + 2),
+                    )
+                }),
+            )
+            .write()
+            // .on_progress(|progress| todo!())
+            .to_buffered(&mut buffered_write)
+            .map_err(to_image_err)?;
+        }
+
+        ColorType::Rgba32F => {
+            exr::prelude::Image // TODO compression method zip??
+                ::from_channels(
+                (width, height),
+                SpecificChannels::rgba(|pixel: Vec2<usize>| {
+                    let pixel_index = 4 * pixel.flat_index_for_size(Vec2(width, height));
+                    (
+                        lookup_f32(pixel_index),
+                        lookup_f32(pixel_index + 1),
+                        lookup_f32(pixel_index + 2),
+                        lookup_f32(pixel_index + 3),
+                    )
+                }),
+            )
+            .write()
+            // .on_progress(|progress| todo!())
+            .to_buffered(&mut buffered_write)
+            .map_err(to_image_err)?;
+        }
+
+        // TODO other color types and channel types
+        unsupported_color_type => {
+            return Err(ImageError::Encoding(EncodingError::new(
+                ImageFormatHint::Exact(ImageFormat::OpenExr),
+                format!(
+                    "writing color type {:?} not yet supported",
+                    unsupported_color_type
+                ),
+            )))
+        }
+    }
+
+    Ok(())
+}
+
+// TODO is this struct and trait actually used anywhere?
+/// A thin wrapper that implements `ImageEncoder` for OpenEXR images. Will behave like `image::codecs::openexr::write_buffer`.
+#[derive(Debug)]
+pub struct OpenExrEncoder<W>(W);
+
+impl<W> OpenExrEncoder<W> {
+    /// Create an `ImageEncoder`. Does not write anything yet. Writing later will behave like `image::codecs::openexr::write_buffer`.
+    // use constructor, not public field, for future backwards-compatibility
+    pub fn new(write: W) -> Self {
+        Self(write)
+    }
+}
+
+impl<W> ImageEncoder for OpenExrEncoder<W>
+where
+    W: Write + Seek,
+{
+    /// Writes the complete image.
+    ///
+    /// Returns an Error if it has an invalid length.
+    /// Assumes the writer is buffered. In most cases,
+    /// you should wrap your writer in a `BufWriter` for best performance.
+    fn write_image(
+        self,
+        buf: &[u8],
+        width: u32,
+        height: u32,
+        color_type: ColorType,
+    ) -> ImageResult<()> {
+        write_buffer(self.0, buf, width, height, color_type)
+    }
+}
+
+fn to_image_err(exr_error: Error) -> ImageError {
+    ImageError::Decoding(DecodingError::new(
+        ImageFormatHint::Exact(ImageFormat::OpenExr),
+        exr_error.to_string(),
+    ))
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    use std::io::BufReader;
+    use std::path::{Path, PathBuf};
+
+    use crate::buffer_::{Rgb32FImage, Rgba32FImage};
+    use crate::error::{LimitError, LimitErrorKind};
+    use crate::{ImageBuffer, Rgb, Rgba};
+
+    const BASE_PATH: &[&str] = &[".", "tests", "images", "exr"];
+
+    /// Write an `Rgb32FImage`.
+    /// Assumes the writer is buffered. In most cases,
+    /// you should wrap your writer in a `BufWriter` for best performance.
+    fn write_rgb_image(write: impl Write + Seek, image: &Rgb32FImage) -> ImageResult<()> {
+        write_buffer(
+            write,
+            bytemuck::cast_slice(image.as_raw().as_slice()),
+            image.width(),
+            image.height(),
+            ColorType::Rgb32F,
+        )
+    }
+
+    /// Write an `Rgba32FImage`.
+    /// Assumes the writer is buffered. In most cases,
+    /// you should wrap your writer in a `BufWriter` for best performance.
+    fn write_rgba_image(write: impl Write + Seek, image: &Rgba32FImage) -> ImageResult<()> {
+        write_buffer(
+            write,
+            bytemuck::cast_slice(image.as_raw().as_slice()),
+            image.width(),
+            image.height(),
+            ColorType::Rgba32F,
+        )
+    }
+
+    /// Read the file from the specified path into an `Rgba32FImage`.
+    fn read_as_rgba_image_from_file(path: impl AsRef<Path>) -> ImageResult<Rgba32FImage> {
+        read_as_rgba_image(BufReader::new(std::fs::File::open(path)?))
+    }
+
+    /// Read the file from the specified path into an `Rgb32FImage`.
+    fn read_as_rgb_image_from_file(path: impl AsRef<Path>) -> ImageResult<Rgb32FImage> {
+        read_as_rgb_image(BufReader::new(std::fs::File::open(path)?))
+    }
+
+    /// Read the file from the specified path into an `Rgb32FImage`.
+    fn read_as_rgb_image(read: impl Read + Seek) -> ImageResult<Rgb32FImage> {
+        let decoder = OpenExrDecoder::with_alpha_preference(read, Some(false))?;
+        let (width, height) = decoder.dimensions();
+        let buffer: Vec<f32> = decoder_to_vec(decoder)?;
+
+        ImageBuffer::from_raw(width, height, buffer)
+            // this should be the only reason for the "from raw" call to fail,
+            // even though such a large allocation would probably cause an error much earlier
+            .ok_or_else(|| {
+                ImageError::Limits(LimitError::from_kind(LimitErrorKind::InsufficientMemory))
+            })
+    }
+
+    /// Read the file from the specified path into an `Rgba32FImage`.
+    fn read_as_rgba_image(read: impl Read + Seek) -> ImageResult<Rgba32FImage> {
+        let decoder = OpenExrDecoder::with_alpha_preference(read, Some(true))?;
+        let (width, height) = decoder.dimensions();
+        let buffer: Vec<f32> = decoder_to_vec(decoder)?;
+
+        ImageBuffer::from_raw(width, height, buffer)
+            // this should be the only reason for the "from raw" call to fail,
+            // even though such a large allocation would probably cause an error much earlier
+            .ok_or_else(|| {
+                ImageError::Limits(LimitError::from_kind(LimitErrorKind::InsufficientMemory))
+            })
+    }
+
+    #[test]
+    fn compare_exr_hdr() {
+        if cfg!(not(feature = "hdr")) {
+            eprintln!("warning: to run all the openexr tests, activate the hdr feature flag");
+        }
+
+        #[cfg(feature = "hdr")]
+        {
+            let folder = BASE_PATH.iter().collect::<PathBuf>();
+            let reference_path = folder.clone().join("overexposed gradient.hdr");
+            let exr_path = folder
+                .clone()
+                .join("overexposed gradient - data window equals display window.exr");
+
+            let hdr: Vec<Rgb<f32>> = crate::codecs::hdr::HdrDecoder::new(std::io::BufReader::new(
+                std::fs::File::open(&reference_path).unwrap(),
+            ))
+            .unwrap()
+            .read_image_hdr()
+            .unwrap();
+
+            let exr_pixels: Rgb32FImage = read_as_rgb_image_from_file(exr_path).unwrap();
+            assert_eq!(
+                exr_pixels.dimensions().0 * exr_pixels.dimensions().1,
+                hdr.len() as u32
+            );
+
+            for (expected, found) in hdr.iter().zip(exr_pixels.pixels()) {
+                for (expected, found) in expected.0.iter().zip(found.0.iter()) {
+                    // the large tolerance seems to be caused by
+                    // the RGBE u8x4 pixel quantization of the hdr image format
+                    assert!(
+                        (expected - found).abs() < 0.1,
+                        "expected {}, found {}",
+                        expected,
+                        found
+                    );
+                }
+            }
+        }
+    }
+
+    #[test]
+    fn roundtrip_rgba() {
+        let mut next_random = vec![1.0, 0.0, -1.0, -3.14, 27.0, 11.0, 31.0]
+            .into_iter()
+            .cycle();
+        let mut next_random = move || next_random.next().unwrap();
+
+        let generated_image: Rgba32FImage = ImageBuffer::from_fn(9, 31, |_x, _y| {
+            Rgba([next_random(), next_random(), next_random(), next_random()])
+        });
+
+        let mut bytes = vec![];
+        write_rgba_image(Cursor::new(&mut bytes), &generated_image).unwrap();
+        let decoded_image = read_as_rgba_image(Cursor::new(bytes)).unwrap();
+
+        debug_assert_eq!(generated_image, decoded_image);
+    }
+
+    #[test]
+    fn roundtrip_rgb() {
+        let mut next_random = vec![1.0, 0.0, -1.0, -3.14, 27.0, 11.0, 31.0]
+            .into_iter()
+            .cycle();
+        let mut next_random = move || next_random.next().unwrap();
+
+        let generated_image: Rgb32FImage = ImageBuffer::from_fn(9, 31, |_x, _y| {
+            Rgb([next_random(), next_random(), next_random()])
+        });
+
+        let mut bytes = vec![];
+        write_rgb_image(Cursor::new(&mut bytes), &generated_image).unwrap();
+        let decoded_image = read_as_rgb_image(Cursor::new(bytes)).unwrap();
+
+        debug_assert_eq!(generated_image, decoded_image);
+    }
+
+    #[test]
+    fn compare_rgba_rgb() {
+        let exr_path = BASE_PATH
+            .iter()
+            .collect::<PathBuf>()
+            .join("overexposed gradient - data window equals display window.exr");
+
+        let rgb: Rgb32FImage = read_as_rgb_image_from_file(&exr_path).unwrap();
+        let rgba: Rgba32FImage = read_as_rgba_image_from_file(&exr_path).unwrap();
+
+        assert_eq!(rgba.dimensions(), rgb.dimensions());
+
+        for (Rgb(rgb), Rgba(rgba)) in rgb.pixels().zip(rgba.pixels()) {
+            assert_eq!(rgb, &rgba[..3]);
+        }
+    }
+
+    #[test]
+    fn compare_cropped() {
+        // like in photoshop, exr images may have layers placed anywhere in a canvas.
+        // we don't want to load the pixels from the layer, but we want to load the pixels from the canvas.
+        // a layer might be smaller than the canvas, in that case the canvas should be transparent black
+        // where no layer was covering it. a layer might also be larger than the canvas,
+        // these pixels should be discarded.
+        //
+        // in this test we want to make sure that an
+        // auto-cropped image will be reproduced to the original.
+
+        let exr_path = BASE_PATH.iter().collect::<PathBuf>();
+        let original = exr_path.clone().join("cropping - uncropped original.exr");
+        let cropped = exr_path
+            .clone()
+            .join("cropping - data window differs display window.exr");
+
+        // smoke-check that the exr files are actually not the same
+        {
+            let original_exr = read_first_flat_layer_from_file(&original).unwrap();
+            let cropped_exr = read_first_flat_layer_from_file(&cropped).unwrap();
+            assert_eq!(
+                original_exr.attributes.display_window,
+                cropped_exr.attributes.display_window
+            );
+            assert_ne!(
+                original_exr.layer_data.attributes.layer_position,
+                cropped_exr.layer_data.attributes.layer_position
+            );
+            assert_ne!(original_exr.layer_data.size, cropped_exr.layer_data.size);
+        }
+
+        // check that they result in the same image
+        let original: Rgba32FImage = read_as_rgba_image_from_file(&original).unwrap();
+        let cropped: Rgba32FImage = read_as_rgba_image_from_file(&cropped).unwrap();
+        assert_eq!(original.dimensions(), cropped.dimensions());
+
+        // the following is not a simple assert_eq, as in case of an error,
+        // the whole image would be printed to the console, which takes forever
+        assert!(original.pixels().zip(cropped.pixels()).all(|(a, b)| a == b));
+    }
+}