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Merge branch 'main' into bp/tiffonlyfirstframe
2 parents ca7e70c + 739aa39 commit 5b2413a

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6 files changed

+80
-12
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6 files changed

+80
-12
lines changed

‎src/ImageSharp/Formats/Tiff/Compression/Decompressors/GrayJpegSpectralConverter.cs‎

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// Copyright (c) Six Labors.
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// Licensed under the Apache License, Version 2.0.
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using SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder;
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using SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder.ColorConverters;
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using SixLabors.ImageSharp.PixelFormats;
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namespace SixLabors.ImageSharp.Formats.Tiff.Compression.Decompressors
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{
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/// <summary>
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/// Spectral converter for gray TIFF's which use the JPEG compression.
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/// </summary>
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/// <typeparam name="TPixel">The type of the pixel.</typeparam>
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internal sealed class GrayJpegSpectralConverter<TPixel> : SpectralConverter<TPixel>
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where TPixel : unmanaged, IPixel<TPixel>
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{
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/// <summary>
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/// Initializes a new instance of the <see cref="GrayJpegSpectralConverter{TPixel}"/> class.
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/// </summary>
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/// <param name="configuration">The configuration.</param>
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public GrayJpegSpectralConverter(Configuration configuration)
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: base(configuration)
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{
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}
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/// <inheritdoc/>
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protected override JpegColorConverterBase GetColorConverter(JpegFrame frame, IRawJpegData jpegData) => JpegColorConverterBase.GetConverter(JpegColorSpace.Grayscale, frame.Precision);
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}
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}

‎src/ImageSharp/Formats/Tiff/Compression/Decompressors/JpegTiffCompression.cs‎

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@@ -9,7 +9,6 @@
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using SixLabors.ImageSharp.Formats.Tiff.Constants;
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using SixLabors.ImageSharp.IO;
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using SixLabors.ImageSharp.Memory;
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using SixLabors.ImageSharp.Metadata;
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using SixLabors.ImageSharp.PixelFormats;
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namespace SixLabors.ImageSharp.Formats.Tiff.Compression.Decompressors
@@ -55,17 +54,41 @@ protected override void Decompress(BufferedReadStream stream, int byteCount, int
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{
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using var jpegDecoder = new JpegDecoderCore(this.configuration, new JpegDecoder());
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// If the PhotometricInterpretation is YCbCr we explicitly assume the JPEG data is in RGB color space.
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// There seems no other way to determine that the JPEG data is RGB colorspace (no APP14 marker, componentId's are not RGB).
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using SpectralConverter<Rgb24> spectralConverter = this.photometricInterpretation == TiffPhotometricInterpretation.YCbCr ?
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new RgbJpegSpectralConverter<Rgb24>(this.configuration) : new SpectralConverter<Rgb24>(this.configuration);
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var scanDecoder = new HuffmanScanDecoder(stream, spectralConverter, CancellationToken.None);
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jpegDecoder.LoadTables(this.jpegTables, scanDecoder);
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scanDecoder.ResetInterval = 0;
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jpegDecoder.ParseStream(stream, scanDecoder, CancellationToken.None);
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switch (this.photometricInterpretation)
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{
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case TiffPhotometricInterpretation.BlackIsZero:
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case TiffPhotometricInterpretation.WhiteIsZero:
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{
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using SpectralConverter<L8> spectralConverterGray = new GrayJpegSpectralConverter<L8>(this.configuration);
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var scanDecoderGray = new HuffmanScanDecoder(stream, spectralConverterGray, CancellationToken.None);
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jpegDecoder.LoadTables(this.jpegTables, scanDecoderGray);
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jpegDecoder.ParseStream(stream, scanDecoderGray, CancellationToken.None);
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// TODO: Should we pass through the CancellationToken from the tiff decoder?
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CopyImageBytesToBuffer(buffer, spectralConverter.GetPixelBuffer(CancellationToken.None));
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// TODO: Should we pass through the CancellationToken from the tiff decoder?
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CopyImageBytesToBuffer(buffer, spectralConverterGray.GetPixelBuffer(CancellationToken.None));
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break;
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}
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// If the PhotometricInterpretation is YCbCr we explicitly assume the JPEG data is in RGB color space.
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// There seems no other way to determine that the JPEG data is RGB colorspace (no APP14 marker, componentId's are not RGB).
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case TiffPhotometricInterpretation.YCbCr:
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case TiffPhotometricInterpretation.Rgb:
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{
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using SpectralConverter<Rgb24> spectralConverter = this.photometricInterpretation == TiffPhotometricInterpretation.YCbCr ?
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new RgbJpegSpectralConverter<Rgb24>(this.configuration) : new SpectralConverter<Rgb24>(this.configuration);
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var scanDecoder = new HuffmanScanDecoder(stream, spectralConverter, CancellationToken.None);
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jpegDecoder.LoadTables(this.jpegTables, scanDecoder);
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jpegDecoder.ParseStream(stream, scanDecoder, CancellationToken.None);
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// TODO: Should we pass through the CancellationToken from the tiff decoder?
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CopyImageBytesToBuffer(buffer, spectralConverter.GetPixelBuffer(CancellationToken.None));
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break;
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}
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default:
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TiffThrowHelper.ThrowNotSupported($"Jpeg compressed tiff with photometric interpretation {this.photometricInterpretation} is not supported");
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break;
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}
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}
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else
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{
@@ -86,6 +109,18 @@ private static void CopyImageBytesToBuffer(Span<byte> buffer, Buffer2D<Rgb24> pi
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}
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}
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private static void CopyImageBytesToBuffer(Span<byte> buffer, Buffer2D<L8> pixelBuffer)
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{
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int offset = 0;
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for (int y = 0; y < pixelBuffer.Height; y++)
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{
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Span<L8> pixelRowSpan = pixelBuffer.DangerousGetRowSpan(y);
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Span<byte> rgbBytes = MemoryMarshal.AsBytes(pixelRowSpan);
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rgbBytes.CopyTo(buffer.Slice(offset));
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offset += rgbBytes.Length;
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}
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}
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/// <inheritdoc/>
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protected override void Dispose(bool disposing)
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{

‎src/ImageSharp/Formats/Tiff/Compression/Decompressors/RgbJpegSpectralConverter.cs‎

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// Copyright (c) Six Labors.
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// Licensed under the Apache License, Version 2.0.
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using System.Threading;
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using SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder;
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using SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder.ColorConverters;
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using SixLabors.ImageSharp.PixelFormats;

‎tests/ImageSharp.Tests/Formats/Tiff/TiffDecoderTests.cs‎

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@@ -382,6 +382,7 @@ public void CanDecodeJustOneFrame<TPixel>(TestImageProvider<TPixel> provider)
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[WithFile(RgbWithStripsJpegCompressed, PixelTypes.Rgba32)]
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[WithFile(YCbCrJpegCompressed, PixelTypes.Rgba32)]
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[WithFile(RgbJpegCompressedNoJpegTable, PixelTypes.Rgba32)]
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[WithFile(GrayscaleJpegCompressed, PixelTypes.Rgba32)]
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public void TiffDecoder_CanDecode_JpegCompressed<TPixel>(TestImageProvider<TPixel> provider)
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where TPixel : unmanaged, IPixel<TPixel> => TestTiffDecoder(provider, useExactComparer: false);
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‎tests/ImageSharp.Tests/TestImages.cs‎

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public const string GrayscaleDeflateMultistrip = "Tiff/grayscale_deflate_multistrip.tiff";
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public const string GrayscaleUncompressed = "Tiff/grayscale_uncompressed.tiff";
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public const string GrayscaleJpegCompressed = "Tiff/JpegCompressedGray.tiff";
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public const string PaletteDeflateMultistrip = "Tiff/palette_grayscale_deflate_multistrip.tiff";
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public const string PaletteUncompressed = "Tiff/palette_uncompressed.tiff";
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public const string RgbDeflate = "Tiff/rgb_deflate.tiff";

‎tests/Images/Input/Tiff/JpegCompressedGray.tiff‎

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version https://git-lfs.github.com/spec/v1
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oid sha256:868afd018d025ed7636f1155c1b1f64ba8a36153b56c7598e8dee18ce770cd5a
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size 539660

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