diff options
| -rw-r--r-- | crates/typst-pdf/src/image.rs | 52 |
1 files changed, 17 insertions, 35 deletions
diff --git a/crates/typst-pdf/src/image.rs b/crates/typst-pdf/src/image.rs index 3857e68f..a4833e6e 100644 --- a/crates/typst-pdf/src/image.rs +++ b/crates/typst-pdf/src/image.rs @@ -113,42 +113,24 @@ pub(crate) fn write_images(ctx: &mut PdfContext) { /// Skips the alpha channel as that's encoded separately. fn encode_raster_image(image: &RasterImage) -> (Vec<u8>, Filter, bool) { let dynamic = image.dynamic(); - match (image.format(), dynamic) { - // 8-bit gray JPEG. - (RasterFormat::Jpg, DynamicImage::ImageLuma8(_)) => { - let mut data = Cursor::new(vec![]); - dynamic.write_to(&mut data, image::ImageFormat::Jpeg).unwrap(); - (data.into_inner(), Filter::DctDecode, false) - } - - // 8-bit RGB JPEG (CMYK JPEGs get converted to RGB earlier). - (RasterFormat::Jpg, DynamicImage::ImageRgb8(_)) => { - let mut data = Cursor::new(vec![]); - dynamic.write_to(&mut data, image::ImageFormat::Jpeg).unwrap(); - (data.into_inner(), Filter::DctDecode, true) - } - + let channel_count = dynamic.color().channel_count(); + let has_color = channel_count > 2; + + if image.format() == RasterFormat::Jpg { + let mut data = Cursor::new(vec![]); + dynamic.write_to(&mut data, image::ImageFormat::Jpeg).unwrap(); + (data.into_inner(), Filter::DctDecode, has_color) + } else { // TODO: Encode flate streams with PNG-predictor? - - // 8-bit gray PNG. - (RasterFormat::Png, DynamicImage::ImageLuma8(luma)) => { - let data = deflate(luma.as_raw()); - (data, Filter::FlateDecode, false) - } - - // Anything else (including Rgb(a) PNGs). - (_, buf) => { - let (width, height) = buf.dimensions(); - let mut pixels = Vec::with_capacity(3 * width as usize * height as usize); - for (_, _, Rgba([r, g, b, _])) in buf.pixels() { - pixels.push(r); - pixels.push(g); - pixels.push(b); - } - - let data = deflate(&pixels); - (data, Filter::FlateDecode, true) - } + let data = match (dynamic, channel_count) { + (DynamicImage::ImageLuma8(luma), _) => deflate(luma.as_raw()), + (DynamicImage::ImageRgb8(rgb), _) => deflate(rgb.as_raw()), + // Grayscale image + (_, 1 | 2) => deflate(dynamic.to_luma8().as_raw()), + // Anything else + _ => deflate(dynamic.to_rgb8().as_raw()), + }; + (data, Filter::FlateDecode, has_color) } } |