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@ -28,44 +28,6 @@ namespace SixLabors.ImageSharp.Formats.Jpeg |
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/// </summary>
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private const int QuantizationTableCount = 2; |
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/// <summary>
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/// Gets the unscaled quantization tables in zig-zag order. Each
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/// encoder copies and scales the tables according to its quality parameter.
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/// The values are derived from section K.1 after converting from natural to
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/// zig-zag order.
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/// </summary>
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// The C# compiler emits this as a compile-time constant embedded in the PE file.
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// This is effectively compiled down to: return new ReadOnlySpan<byte>(&data, length)
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// More details can be found: https://github.com/dotnet/roslyn/pull/24621
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private static ReadOnlySpan<byte> UnscaledQuant_Luminance => new byte[] |
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{ |
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// Luminance.
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16, 11, 12, 14, 12, 10, 16, 14, 13, 14, 18, 17, 16, 19, 24, |
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40, 26, 24, 22, 22, 24, 49, 35, 37, 29, 40, 58, 51, 61, 60, |
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57, 51, 56, 55, 64, 72, 92, 78, 64, 68, 87, 69, 55, 56, 80, |
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109, 81, 87, 95, 98, 103, 104, 103, 62, 77, 113, 121, 112, |
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100, 120, 92, 101, 103, 99, |
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}; |
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/// <summary>
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/// Gets the unscaled quantization tables in zig-zag order. Each
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/// encoder copies and scales the tables according to its quality parameter.
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/// The values are derived from section K.1 after converting from natural to
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/// zig-zag order.
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/// </summary>
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// The C# compiler emits this as a compile-time constant embedded in the PE file.
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// This is effectively compiled down to: return new ReadOnlySpan<byte>(&data, length)
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// More details can be found: https://github.com/dotnet/roslyn/pull/24621
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private static ReadOnlySpan<byte> UnscaledQuant_Chrominance => new byte[] |
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{ |
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// Chrominance.
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17, 18, 18, 24, 21, 24, 47, 26, 26, 47, 99, 66, 56, 66, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, |
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}; |
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/// <summary>
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/// A scratch buffer to reduce allocations.
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/// </summary>
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@ -102,6 +64,44 @@ namespace SixLabors.ImageSharp.Formats.Jpeg |
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this.colorType = options.ColorType; |
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} |
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/// <summary>
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/// Gets the unscaled quantization tables in zig-zag order. Each
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/// encoder copies and scales the tables according to its quality parameter.
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/// The values are derived from section K.1 after converting from natural to
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/// zig-zag order.
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/// </summary>
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// The C# compiler emits this as a compile-time constant embedded in the PE file.
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// This is effectively compiled down to: return new ReadOnlySpan<byte>(&data, length)
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// More details can be found: https://github.com/dotnet/roslyn/pull/24621
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private static ReadOnlySpan<byte> UnscaledQuant_Luminance => new byte[] |
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{ |
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// Luminance.
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16, 11, 12, 14, 12, 10, 16, 14, 13, 14, 18, 17, 16, 19, 24, |
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40, 26, 24, 22, 22, 24, 49, 35, 37, 29, 40, 58, 51, 61, 60, |
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57, 51, 56, 55, 64, 72, 92, 78, 64, 68, 87, 69, 55, 56, 80, |
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109, 81, 87, 95, 98, 103, 104, 103, 62, 77, 113, 121, 112, |
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100, 120, 92, 101, 103, 99, |
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}; |
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/// <summary>
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/// Gets the unscaled quantization tables in zig-zag order. Each
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/// encoder copies and scales the tables according to its quality parameter.
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/// The values are derived from section K.1 after converting from natural to
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/// zig-zag order.
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/// </summary>
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// The C# compiler emits this as a compile-time constant embedded in the PE file.
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// This is effectively compiled down to: return new ReadOnlySpan<byte>(&data, length)
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// More details can be found: https://github.com/dotnet/roslyn/pull/24621
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private static ReadOnlySpan<byte> UnscaledQuant_Chrominance => new byte[] |
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{ |
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// Chrominance.
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17, 18, 18, 24, 21, 24, 47, 26, 26, 47, 99, 66, 56, 66, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, |
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99, 99, 99, 99, 99, 99, 99, 99, |
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}; |
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/// <summary>
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/// Encode writes the image to the jpeg baseline format with the given options.
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/// </summary>
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@ -180,7 +180,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg |
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} |
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else |
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{ |
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switch (subsample) |
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switch (this.subsample) |
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{ |
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case JpegSubsample.Ratio444: |
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scanEncoder.Encode444(image, ref luminanceQuantTable, ref chrominanceQuantTable, cancellationToken); |
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James Jackson-South
5 years ago
GitHub