Vectorize TrimTransparentPixels in GifEncoderCore by gfoidl · Pull Request #2500 · SixLabors/ImageSharp

gfoidl · 2023-07-27T19:29:26Z

Prerequisites

I have written a descriptive pull-request title
I have verified that there are no overlapping pull-requests open
I have verified that I am following the existing coding patterns and practice as demonstrated in the repository. These follow strict Stylecop rules 👮.
I have provided test coverage for my change (where applicable)

Description

A simple benchmark -- just for the inner loop -- yields:

|     Method |      Mean |    Error |   StdDev | Ratio |
|----------- |----------:|---------:|---------:|------:|
|    Default | 102.33 ns | 2.073 ns | 2.973 ns |  1.00 |
| Vectorized |  16.53 ns | 0.065 ns | 0.055 ns |  0.16 |

This is measured with .NET 7, but the codegen for .NET 6 is very similar.

benchmark code

using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Intrinsics;
using BenchmarkDotNet.Attributes;

Bench bench = new();
bench.Setup();
Console.WriteLine(bench.Default());
Console.WriteLine(bench.Vectorized());

#if !DEBUG
BenchmarkDotNet.Running.BenchmarkRunner.Run<Bench>();
#endif

public class Bench
{
    private byte[] _rowSpan = null!;
    private byte _trimmableIndex;

    [GlobalSetup]
    public void Setup()
    {
        _rowSpan = new byte[100];
        _rowSpan.AsSpan().Fill(42);
        _rowSpan.AsSpan(25, 9).Clear();

        _trimmableIndex = 42;
    }

    [Benchmark(Baseline = true)]
    public (int left, int right, bool isTransparentRow) Default()
    {
        Span<byte> rowSpan = _rowSpan;
        byte trimmableIndex = _trimmableIndex;

        int left = int.MaxValue;
        int right = int.MinValue;
        bool isTransparentRow = true;

        for (int x = 0; x < rowSpan.Length; ++x)
        {
            if (rowSpan[x] != trimmableIndex)
            {
                isTransparentRow = false;
                left = Math.Min(left, x);
                right = Math.Max(right, x);
            }
        }

        if (left == int.MaxValue)
        {
            left = 0;
        }

        if (right == int.MinValue)
        {
            right = rowSpan.Length;
        }

        return (left, right, isTransparentRow);
    }

    [Benchmark]
    public (int left, int right, bool isTransparentRow) Vectorized()
    {
        Span<byte> rowSpan = _rowSpan;
        byte trimmableIndex = _trimmableIndex;

        int left = int.MaxValue;
        int right = int.MinValue;
        bool isTransparentRow = true;

        ref byte rowPtr = ref MemoryMarshal.GetReference(rowSpan);
        nint rowLength = (nint)(uint)rowSpan.Length;
        nint x = 0;

        if (Vector128.IsHardwareAccelerated && rowLength >= Vector128<byte>.Count)
        {
            Vector256<byte> trimmableVec256 = Vector256.Create(trimmableIndex);

            if (Vector256.IsHardwareAccelerated && rowLength >= Vector256<byte>.Count)
            {
                do
                {
                    Vector256<byte> vec = Vector256.LoadUnsafe(ref rowPtr, (nuint)x);
                    Vector256<byte> notEquals = ~Vector256.Equals(vec, trimmableVec256);

                    if (notEquals != Vector256<byte>.Zero)
                    {
                        isTransparentRow = false;
                        uint mask = notEquals.ExtractMostSignificantBits();
                        nint start = x + (nint)uint.TrailingZeroCount(mask);

                        nint end = (nint)uint.LeadingZeroCount(mask);
                        // end is from the end, but we need the index from the beginning
                        end = x + Vector256<byte>.Count - 1 - end;

                        left = Math.Min(left, (int)start);
                        right = Math.Max(right, (int)end);
                    }

                    x += Vector256<byte>.Count;
                }
                while (x <= rowLength - Vector256<byte>.Count);
            }

            Vector128<byte> trimmableVec = Vector256.IsHardwareAccelerated
                ? trimmableVec256.GetLower()
                : Vector128.Create(trimmableIndex);

            while (x <= rowLength - Vector128<byte>.Count)
            {
                Vector128<byte> vec = Vector128.LoadUnsafe(ref rowPtr, (nuint)x);
                Vector128<byte> notEquals = ~Vector128.Equals(vec, trimmableVec);

                if (notEquals != Vector128<byte>.Zero)
                {
                    isTransparentRow = false;
                    uint mask = notEquals.ExtractMostSignificantBits();
                    nint start = x + (nint)uint.TrailingZeroCount(mask);

                    nint end = (nint)uint.LeadingZeroCount(mask) - Vector128<byte>.Count;
                    // end is from the end, but we need the index from the beginning
                    end = x + Vector128<byte>.Count - 1 - end;

                    left = Math.Min(left, (int)start);
                    right = Math.Max(right, (int)end);
                }

                x += Vector128<byte>.Count;
            }
        }

        for (; x < rowLength; ++x)
        {
            if (Unsafe.Add(ref rowPtr, x) != trimmableIndex)
            {
                isTransparentRow = false;
                left = Math.Min(left, (int)x);
                right = Math.Max(right, (int)x);
            }
        }

        if (left == int.MaxValue)
        {
            left = 0;
        }

        if (right == int.MinValue)
        {
            right = (int)rowLength;
        }

        return (left, right, isTransparentRow);
    }
}

gfoidl

Some notes for review.

gfoidl · 2023-07-27T19:33:17Z

+                        Vector256<byte> vec = Vector256.LoadUnsafe(ref rowPtr, (nuint)x);
+                        Vector256<byte> notEquals = ~Vector256.Equals(vec, trimmableVec256);
+
+                        if (notEquals != Vector256<byte>.Zero)


At the moment I don't have any idea on how to make this branchless.
isTransparentRow could be tracked in a vector, but left and right not, as there's a mismatch of vector-types, namely byte and int.

A quite complicated approach would be to use VectorXYZ<byte> and track the left and right -- but just before these can overflow merge it back to the scalar left, right and start over. But I guess the book-keeping is more work, so I'm not sure if this is actually faster. For sure the code gets painful.

gfoidl · 2023-07-27T19:35:45Z

+                }
+            }
+#endif
+            for (; x < rowLength; ++x)


The remainder could be handled vectorized too, by shifting the mask of the most significant bits around by the count of elements left in the final vector.
I tried this somewhere else, the cost for that book-keeping isn't negligible, so didn't do this here and now (maybe I'll try this later).

Hm, I remembered that movemask isn't the fastest, and ptest (TestZ in .NET-terms) is faster but current benchmarks didn't prove this, also Intel's instruction table didn't show any benefit in terms of latency or throughput. Thus simplified that check.

JimBobSquarePants · 2023-07-29T08:59:28Z

Oof! Look at those numbers!! Thanks so much for looking at this. I'm going have a good dig through it to wrap my head round what you have done.

gfoidl · 2023-07-29T09:04:47Z

😃
I think the easiest way to understand / check is to use the benchmark-code (see top-comment) in a simple console app and step with the debugger through it (maybe change the size of the _rowSpan to 20 or that like.
Calculation of the correct index for end is the strangest part IMO.

PS: I'm back on Tuesday, so maybe slow to respond in the meantime.

JimBobSquarePants · 2023-08-09T11:30:27Z

This is fantastic stuff. I figured theoretically after reading some of the source for Span.IndexOf that masking with bit counting would be the vectorized solution I just had no idea how I'd actually implement it.

Tip of the cap to you sir.

gfoidl · 2023-08-09T12:15:01Z

Thanks for the kind words ❤️

Updated [SixLabors.ImageSharp](https://github.com/SixLabors/ImageSharp) from 2.1.9 to 4.1.2. <details> <summary>Release notes</summary> _Sourced from [SixLabors.ImageSharp's releases](https://github.com/SixLabors/ImageSharp/releases)._ ## 4.1.2 ## What's Changed * Harden codec and metadata input validation by @JimBobSquarePants in SixLabors/ImageSharp#3187 * Fix TIFF decoding of legacy 8-bit color maps by @JimBobSquarePants in SixLabors/ImageSharp#3189 **Full Changelog**: SixLabors/ImageSharp@v4.1.1...v4.1.2 ## 4.1.1 ## What's Changed * Fix CCITT decompressor bounds checks and error handling by @JimBobSquarePants in SixLabors/ImageSharp#3176 **Full Changelog**: SixLabors/ImageSharp@v4.1.0...v4.1.1 ## 4.1.0 ## What's Changed * GIF: background handling & quantizer overflow fix by @JimBobSquarePants in SixLabors/ImageSharp#3133 * Validate PBM max pixel value by @JimBobSquarePants in SixLabors/ImageSharp#3134 * Add support for Apple CgBI PNG images by @Erik-White in SixLabors/ImageSharp#3136 * Fix GIF transparency handling and dither by @JimBobSquarePants in SixLabors/ImageSharp#3143 * Bump codecov/codecov-action from 6 to 7 by @dependabot[bot] in SixLabors/ImageSharp#3141 * Add BlendWithCoverage overloads. Optimize Rgba32 compatible shuffling. by @JimBobSquarePants in SixLabors/ImageSharp#3150 * Bump actions/checkout from 6 to 7 by @dependabot[bot] in SixLabors/ImageSharp#3146 * Bump actions/cache from 5 to 6 by @dependabot[bot] in SixLabors/ImageSharp#3149 * Fix convolution sampling for bounds smaller than the kernel radius by @JimBobSquarePants in SixLabors/ImageSharp#3152 * Enhance pixel formats and associated-alpha operations with optimizations by @JimBobSquarePants in SixLabors/ImageSharp#3154 * Bump actions/setup-dotnet from 5 to 6 by @dependabot[bot] in SixLabors/ImageSharp#3155 * Fix degeneracy check for resize transforms by @JimBobSquarePants in SixLabors/ImageSharp#3157 * Improvements to Apple CgBI PNG handling by @Erik-White in SixLabors/ImageSharp#3137 * Clone TIFF profiles into image metadata by @JimBobSquarePants in SixLabors/ImageSharp#3159 * Add AOT compiler seeds for pixel formats and ICO, CUR, QOI codecs by @JimBobSquarePants in SixLabors/ImageSharp#3160 * Normalize SIMD pipelines using TensorPrimitives_ by @JimBobSquarePants in SixLabors/ImageSharp#3161 * Add ANI decoder support by @Poker-sang in SixLabors/ImageSharp#2899 * Remove AntialiasThreshold from GraphicsOptions by @JimBobSquarePants in SixLabors/ImageSharp#3162 * Add plus and extended pixel blend modes by @JimBobSquarePants in SixLabors/ImageSharp#3163 * Fix 16-bit binary PBM sample byte order by @JimBobSquarePants in SixLabors/ImageSharp#3164 * Make MemoryAllocator limits configurable and extensible by @JimBobSquarePants in SixLabors/ImageSharp#3165 ## New Contributors * @Erik-White made their first contribution in SixLabors/ImageSharp#3136 **Full Changelog**: SixLabors/ImageSharp@v4.0.0...v4.1.0 ## 4.0.0 ## What's Changed * Update to net8 by @stefannikolei in SixLabors/ImageSharp#2583 * Handle dedup of local palette of 256 length - Main by @JimBobSquarePants in SixLabors/ImageSharp#2607 * Replace custom Crc32 by @JimBobSquarePants in SixLabors/ImageSharp#2611 * Sync 3.1 DrawImage fixes by @tocsoft in SixLabors/ImageSharp#2612 * Fix handling gif encoding for global palettes - Main by @JimBobSquarePants in SixLabors/ImageSharp#2615 * Bump actions/setup-dotnet from 3 to 4 by @dependabot[bot] in SixLabors/ImageSharp#2613 * Adjusted the casing of the Webp format name by @jscarle in SixLabors/ImageSharp#2623 * Fix Paeth Filter decode on platforms that do not support Ssse3 - Main by @JimBobSquarePants in SixLabors/ImageSharp#2620 * Fix WebP animation speed bug by @marklagendijk in SixLabors/ImageSharp#2624 * Promote PixelTypeInfo to Pixel by @stefannikolei in SixLabors/ImageSharp#2601 * TGA: Treat 32 bit True Color images always as transparent by @brianpopow in SixLabors/ImageSharp#2643 * Modernize and optimize pixel format operations across platforms. by @JimBobSquarePants in SixLabors/ImageSharp#2645 * Cleanup SimdUtils by @JimBobSquarePants in SixLabors/ImageSharp#2654 * Bump actions/cache from 3 to 4 by @dependabot[bot] in SixLabors/ImageSharp#2648 * Bump codecov/codecov-action from 3 to 4 by @dependabot[bot] in SixLabors/ImageSharp#2657 * Bump NuGet/setup-nuget from 1 to 2 by @dependabot[bot] in SixLabors/ImageSharp#2658 * Add v3.1.x fixes #2673 and #2674 into main. by @JimBobSquarePants in SixLabors/ImageSharp#2675 * Add fixes 2668, 2676, and 2677 to main by @JimBobSquarePants in SixLabors/ImageSharp#2678 * Merge 2681 to v4 Main by @JimBobSquarePants in SixLabors/ImageSharp#2690 * Add JPEG COM marker support by @RobertMut in SixLabors/ImageSharp#2641 * Bump actions/upload-artifact from 3 to 4 by @dependabot[bot] in SixLabors/ImageSharp#2625 * Only exit JPEG scan decoding after multiple EOF hits by @JimBobSquarePants in SixLabors/ImageSharp#2701 * V4 Ensure VP8X alpha flag is updated correctly. by @JimBobSquarePants in SixLabors/ImageSharp#2703 * Fix animated png handling (issue #2708) by @SpaceCheetah in SixLabors/ImageSharp#2710 * Merge latest release from v3 by @JimBobSquarePants in SixLabors/ImageSharp#2720 * Fix MacOS jobs by @antonfirsov in SixLabors/ImageSharp#2728 * Fix async-over-sync issue in Image.DecodeAsync() by @kroymann in SixLabors/ImageSharp#2725 * Fix overflow in MemoryAllocator.Create(options) by @antonfirsov in SixLabors/ImageSharp#2730 * GifDecoder: Limit lzw bits to a maximum of 12 bits by @brianpopow in SixLabors/ImageSharp#2744 * GifDecoder : Allow skipping bad metadata using identify by @JimBobSquarePants in SixLabors/ImageSharp#2749 * Add ICO and CUR file decoder. by @frg2089 in SixLabors/ImageSharp#2579 * v4 - Fix off-by-one error when centering a transform. by @JimBobSquarePants in SixLabors/ImageSharp#2761 * v4 Fix 2758 by @JimBobSquarePants in SixLabors/ImageSharp#2764 * Simplify Color Space Conversion APIs by @JimBobSquarePants in SixLabors/ImageSharp#2739 * Webp: Fix Issue 2763 by @brianpopow in SixLabors/ImageSharp#2767 * V4 Correctly break during Png decoding by @JimBobSquarePants in SixLabors/ImageSharp#2773 * V4 : Fix filtering on PNG encode. by @JimBobSquarePants in SixLabors/ImageSharp#2778 * Fix #2779 buffer overrun by @KirillAldashkin in SixLabors/ImageSharp#2780 * Fix ImageMetadata docs typo by @lofcz in SixLabors/ImageSharp#2781 * Add API for metadata conversion between formats. by @JimBobSquarePants in SixLabors/ImageSharp#2751 * Tiff decoder: Fix issue 2679 by @brianpopow in SixLabors/ImageSharp#2789 * Replace PngCrcChunkHandling by @JimBobSquarePants in SixLabors/ImageSharp#2786 * Add tagname to debugger visualization for Exif- and Iptc-values, to facilitate easier debugging and discovery by @lassevk in SixLabors/ImageSharp#2787 * V4 - Correctly handle transform spaces when building transform matrices. by @JimBobSquarePants in SixLabors/ImageSharp#2795 * Allow decoding Tiff of different frame size. by @JimBobSquarePants in SixLabors/ImageSharp#2788 * Add progressive JPEG encoder by @ardabada in SixLabors/ImageSharp#2740 * Fix using dither in BmpEncoder when bit per pixel is <= 4 by @mistoll in SixLabors/ImageSharp#2819 * Add QuadDistortion to ProjectiveTransformBuilder by @Socolin in SixLabors/ImageSharp#2748 * WEBP : Use Correct Width With AlphaDecoder by @JimBobSquarePants in SixLabors/ImageSharp#2823 ... (truncated) ## 3.1.12 ## What's Changed * v3 : Add Full Metadata Parsing for WEBP Animations by @JimBobSquarePants in SixLabors/ImageSharp#3002 * V3: Prevent negative allocation attempt for huge TIFF files by @JimBobSquarePants in SixLabors/ImageSharp#3004 * Backport v3 : Tiff decoder: Fix issue 2679 by @JimBobSquarePants in SixLabors/ImageSharp#3007 **Full Changelog**: SixLabors/ImageSharp@v3.1.11...v3.1.12 ## 3.1.11 ## What's Changed * Backport V3 - GIF: Check for end of stream when reading comments. by @JimBobSquarePants in SixLabors/ImageSharp#2955 **Full Changelog**: SixLabors/ImageSharp@v3.1.10...v3.1.11 ## 3.1.10 ## What's Changed * V3: Remove ExifTagValue.InteroperabilityIndex by @JimBobSquarePants in SixLabors/ImageSharp#2939 * V3 TIFF : Allow additional and undefined extra samples by @JimBobSquarePants in SixLabors/ImageSharp#2942 * V3 Use EXIF byte order for EXIF encoded strings. by @JimBobSquarePants in SixLabors/ImageSharp#2944 * V3 Backport : Reduce the number of memory allocations in lossless WebP encoder by @JimBobSquarePants in SixLabors/ImageSharp#2947 **Full Changelog**: SixLabors/ImageSharp@v3.1.9...v3.1.10 ## 3.1.9 ## What's Changed * V3: Do not attempt to decode iDAT chunks when image is fully decoded. by @JimBobSquarePants in SixLabors/ImageSharp#2927 * V3 - Do not throw exception for non-required chunks. by @JimBobSquarePants in SixLabors/ImageSharp#2929 * V3: Do not encode WEBP images exceeding max dimensions by @JimBobSquarePants in SixLabors/ImageSharp#2931 **Full Changelog**: SixLabors/ImageSharp@v3.1.8...v3.1.9 ## 3.1.8 ## What's Changed * V3 : Fix GIF, PNG, and WEBP Edge Case Handling by @JimBobSquarePants in SixLabors/ImageSharp#2882 * V3 Nested sub ifds parsing fix by @JimBobSquarePants in SixLabors/ImageSharp#2913 * V3: Undo horizontal prediction for each tile row in case of tiled tiff's by @JimBobSquarePants in SixLabors/ImageSharp#2914 * V3 - Use BPP from Color Writer for Compressor by @JimBobSquarePants in SixLabors/ImageSharp#2915 **Full Changelog**: SixLabors/ImageSharp@v3.1.7...v3.1.8 ## 3.1.7 ## What's Changed * V3 : Decode Chunky Tile Rows Directly. by @JimBobSquarePants in SixLabors/ImageSharp#2874 * V3: Gracefully handle LZW overflows by @JimBobSquarePants in SixLabors/ImageSharp#2880 * [3.1] Set LangVersion=12 unconditionally by @antonfirsov in SixLabors/ImageSharp#2896 **Full Changelog**: SixLabors/ImageSharp@v3.1.6...v3.1.7 ## 3.1.6 ## What's Changed * Mono AOT decoder workaround for slow jpeg decoding. by @JimBobSquarePants in SixLabors/ImageSharp#2762 * V3 - Correctly handle transform spaces when building transform matrices. by @JimBobSquarePants in SixLabors/ImageSharp#2791 * Backport : V3 Fix #2779 buffer overrun by @JimBobSquarePants in SixLabors/ImageSharp#2824 * Backport - v3 WEBP : Use Correct Width With AlphaDecoder by @JimBobSquarePants in SixLabors/ImageSharp#2827 * Rewrite ChunkedMemoryStream by @JimBobSquarePants in SixLabors/ImageSharp#2828 **Full Changelog**: SixLabors/ImageSharp@v3.1.5...v3.1.6 ## 3.1.5 ## What's Changed * [3.1] Fix overflow in MemoryAllocator.Create(options) by @antonfirsov in SixLabors/ImageSharp#2731 * v3 - Backport. Handle out of bounds Gif LZW max code by @JimBobSquarePants in SixLabors/ImageSharp#2754 * Fix off-by-one error when centering a transform. by @JimBobSquarePants in SixLabors/ImageSharp#2760 * v3.1.x Fix 2758 by @JimBobSquarePants in SixLabors/ImageSharp#2759 * v3.1.x - Backport Webp: Fix Issue 2763/2692 by @JimBobSquarePants in SixLabors/ImageSharp#2768 * Correctly break during Png decoding by @JimBobSquarePants in SixLabors/ImageSharp#2769 * Fix filtering on PNG encode. by @JimBobSquarePants in SixLabors/ImageSharp#2775 **Full Changelog**: SixLabors/ImageSharp@v3.1.4...v3.1.5 ## 3.1.4 ## What's Changed * Backport - Only exit JPEG scan decoding after multiple EOF hits by @JimBobSquarePants in SixLabors/ImageSharp#2702 * Ensure VP8X alpha flag is updated correctly. by @JimBobSquarePants in SixLabors/ImageSharp#2699 * Backport APNG fix to release/3.1.x by @SpaceCheetah in SixLabors/ImageSharp#2713 * Limit Read Palette Indices by @JimBobSquarePants in SixLabors/ImageSharp#2718 * Limit all memory allocations in the MemoryAllocator layer by @antonfirsov in SixLabors/ImageSharp#2706 * Clear Pixel Buffers on Decode. by @JimBobSquarePants in SixLabors/ImageSharp#2716 **Full Changelog**: SixLabors/ImageSharp@v3.1.3...v3.1.4 ## 3.1.3 ## What's Changed * Make DrawImage processor more robust to bad input. by @JimBobSquarePants in SixLabors/ImageSharp#2673 * Don't skip reading data for animation chunks on identify. by @JimBobSquarePants in SixLabors/ImageSharp#2674 * Fix AccessViolationException and hard crash with animated webp by @JimBobSquarePants in SixLabors/ImageSharp#2676 * Use a smarter approach to determine the transparent index when encoding palette Pngs. by @JimBobSquarePants in SixLabors/ImageSharp#2677 * Limit ancillary PNG chunk size. by @JimBobSquarePants in SixLabors/ImageSharp#2681 **Full Changelog**: SixLabors/ImageSharp@v3.1.2...v3.1.3 ## 3.1.2 ## What's Changed * Fix Paeth Filter decode on platforms that do not support Ssse3 by @JimBobSquarePants in SixLabors/ImageSharp#2618 * Backport: Fix WebP animation speed bug by @JimBobSquarePants in SixLabors/ImageSharp#2637 **Full Changelog**: SixLabors/ImageSharp@v3.1.1...v3.1.2 ## 3.1.1 ## What's Changed * Handle dedup of local palette of 256 length by @JimBobSquarePants in SixLabors/ImageSharp#2605 * Correctly calculate foreground Rectangle when negative background location is set (3.1 fix) by @tocsoft in SixLabors/ImageSharp#2609 * Handle case when Foreground image overhangs bottom of background image during DrawImage Call (3.1 target) by @tocsoft in SixLabors/ImageSharp#2610 * Fix handling gif encoding for global palettes. by @JimBobSquarePants in SixLabors/ImageSharp#2614 **Full Changelog**: SixLabors/ImageSharp@v3.1.0...v3.1.1 ## 3.1.0 ## What's Changed * Reduced intermediate allocations by @gfoidl in SixLabors/ImageSharp#2415 * Port colorconverter YCbCr and YCCk to arm by @stefannikolei in SixLabors/ImageSharp#2417 * Added and used Numerics.Vector{128|256}Count extension by @gfoidl in SixLabors/ImageSharp#2422 * Improvements around `fixed` by @gfoidl in SixLabors/ImageSharp#2418 * Create vector constants inline and not via ROS<byte> by @gfoidl in SixLabors/ImageSharp#2419 * More tests for Webp lossless utils by @brianpopow in SixLabors/ImageSharp#2424 * Fix incorrect comments by @hey-red in SixLabors/ImageSharp#2426 * Fixed invalid jpeg buffer width compliment for scalar color converters by @br3aker in SixLabors/ImageSharp#2427 * Update Readme by @brianpopow in SixLabors/ImageSharp#2433 * Add AdvSimd in ComponentProcessor by @stefannikolei in SixLabors/ImageSharp#2429 * Fix decoding tiled tiff with unequal tile width and height by @brianpopow in SixLabors/ImageSharp#2436 * Fix Vp8Residual costs calculation by @brianpopow in SixLabors/ImageSharp#2432 * Fix thresholds for Resize kernel tests by @brianpopow in SixLabors/ImageSharp#2440 * Tiff: Undo horizontal predictor for cmyk images by @brianpopow in SixLabors/ImageSharp#2459 * fix a typo in XML comment for struct `Rgb48` by @n0099 in SixLabors/ImageSharp#2463 * Fix #2467 bmp encoding issue for BMP with 1 bit per pixel and more pixels per row than divisible by 8. by @synercoder in SixLabors/ImageSharp#2471 * Update Directory.Build.targets by @Pashkinz92 in SixLabors/ImageSharp#2468 * bugfix in Rational.cs, when both Nominator and Denominator equals to 0 by @tsardaryanCamenAI in SixLabors/ImageSharp#2453 * Fix DrawImage offsetting issues and improve API parameter names. by @JimBobSquarePants in SixLabors/ImageSharp#2474 * Use more accurate bit for alpha lookup. by @JimBobSquarePants in SixLabors/ImageSharp#2473 * Fix for B&W pbm images with width not dividable by 8 by @ynse01 in SixLabors/ImageSharp#2481 * Tiff: ccitt compression, fix for issue #2451 by @brianpopow in SixLabors/ImageSharp#2483 * Use `FileOptions.Asynchronous` when doing async IO by @Neme12 in SixLabors/ImageSharp#2488 * Allow JFXX as an App0 marker header by @JimBobSquarePants in SixLabors/ImageSharp#2482 * Adding QOI support by @LuisAlfredo92 in SixLabors/ImageSharp#2446 * Vectorize TrimTransparentPixels in GifEncoderCore by @gfoidl in SixLabors/ImageSharp#2500 * Prevent crafted DOS attack. by @JimBobSquarePants in SixLabors/ImageSharp#2501 * Reverse automatic include behavior. by @JimBobSquarePants in SixLabors/ImageSharp#2515 * Handle EOF in Jpeg bit reader when data is bad to prevent DOS attack.… by @JimBobSquarePants in SixLabors/ImageSharp#2523 * Fix #2518 by @antonfirsov in SixLabors/ImageSharp#2519 * Fix for issue 2504 - IPTC and ICC profile information being lost during TIFF file save by @JeffP134 in SixLabors/ImageSharp#2535 * Preserve Gif color palettes and deduplicate frame pixels. by @JimBobSquarePants in SixLabors/ImageSharp#2455 * Bump actions/checkout from 3 to 4 by @dependabot in SixLabors/ImageSharp#2530 * Expose and conserve the color palette for indexed png images. by @JimBobSquarePants in SixLabors/ImageSharp#2485 * Change ExifTag TimeZoneOffset to Signed Short by @Cheesebaron in SixLabors/ImageSharp#2541 * Expose non-nullable configuration to remove AOT limiting null check by @JimBobSquarePants in SixLabors/ImageSharp#2514 * Add GPSHPositioningError exif tag by @Cheesebaron in SixLabors/ImageSharp#2543 * Disallow allocation attempts of unrepresentable sizes by @antonfirsov in SixLabors/ImageSharp#2545 * Add webp decoder option to handle the background color in ANIM chunk by @brianpopow in SixLabors/ImageSharp#2547 * Tiff decoding robustness improvements by @JimBobSquarePants in SixLabors/ImageSharp#2550 * PBM decoder robustness improvements and BufferedReadStream observability by @antonfirsov in SixLabors/ImageSharp#2551 * Follow up on post-merge discussions in #2551 by @antonfirsov in SixLabors/ImageSharp#2552 * APNG support by @Poker-sang in SixLabors/ImageSharp#2511 * WebP - Reduce the allocations in lossless encoding by @JimBobSquarePants in SixLabors/ImageSharp#2546 * Animated webp encoder by @Poker-sang in SixLabors/ImageSharp#2569 * Fix boxed quantization and update refs by @JimBobSquarePants in SixLabors/ImageSharp#2582 * Explicitly set BitsPerPixel and BitsPerSample to 1 for bicolor compressed images by @brianpopow in SixLabors/ImageSharp#2590 * [fix]: Fixed Unknown App0 Marker add profileResolver missing by @JoseEliasSantos in SixLabors/ImageSharp#2566 * Png- Do not attempt to read data for chunks of length 0. by @JimBobSquarePants in SixLabors/ImageSharp#2561 ... (truncated) ## 3.0.2 ## What's Changed * Handle EOF in Jpeg bit reader when data is bad to prevent DOS attack. by @JimBobSquarePants in SixLabors/ImageSharp#2516 **Full Changelog**: SixLabors/ImageSharp@v3.0.1...v3.0.2 ## 3.0.1 ## What's Changed * ISSUE #2385 - Implementing try get pattern to TryFindFormatByFileExtension(string extension, [NotNullWhen(true)] out IImageFormat? format) by @Ollie-Ave in SixLabors/ImageSharp#2386 * Remove mac specific skips by @stefannikolei in SixLabors/ImageSharp#2384 * Add Arm intrinsics to JpegColorConverter RGB by @stefannikolei in SixLabors/ImageSharp#2397 * Add arm64 intrinsics for cmyk converter by @stefannikolei in SixLabors/ImageSharp#2400 * Low-hanging fruit codegen optimizations by @gfoidl in SixLabors/ImageSharp#2401 * Webp: Dont use using statement for encodedAlphaData by @brianpopow in SixLabors/ImageSharp#2412 * Fixed wrong division hack by @gfoidl in SixLabors/ImageSharp#2413 * Port GrayscalConverter to Arm by @stefannikolei in SixLabors/ImageSharp#2409 * Fix RgbScalar by @stefannikolei in SixLabors/ImageSharp#2416 ## New Contributors * @Ollie-Ave made their first contribution in SixLabors/ImageSharp#2386 **Full Changelog**: SixLabors/ImageSharp@v3.0.0...v3.0.1 ## 3.0.0 ## What's Changed * Use .NET 6 only by @JimBobSquarePants in SixLabors/ImageSharp#2098 * Convolution: Border wrapping modes by @ynse01 in SixLabors/ImageSharp#2060 * Use ReadOnlySpan<byte> static data compiler optimization in more places by @turbedi in SixLabors/ImageSharp#2101 * Add support for decoding jpeg's with arithmetic coding by @brianpopow in SixLabors/ImageSharp#2073 * Replace Array.Clear(array, 0, array.Length) calls with Array.Clear(array) by @turbedi in SixLabors/ImageSharp#2103 * Preserve color profile when encoding bitmaps by @brianpopow in SixLabors/ImageSharp#2108 * Preserve color profile when encoding webp images by @brianpopow in SixLabors/ImageSharp#2109 * Preserve color profile when encoding PNG images by @brianpopow in SixLabors/ImageSharp#2110 * Add support for decoding webp images with animations by @brianpopow in SixLabors/ImageSharp#1985 * Jpeg compressed tiff: jpeg decoder should handle the conversion from YCbCr to RGB by @brianpopow in SixLabors/ImageSharp#2124 * Deduce color space as YCbCr if component id's are 1, 2, 3 by @brianpopow in SixLabors/ImageSharp#2135 * Bump actions/checkout from 2 to 3 by @dependabot in SixLabors/ImageSharp#2145 * Bump actions/setup-dotnet from 1 to 2 by @dependabot in SixLabors/ImageSharp#2143 * Bump actions/cache from 2 to 3 by @dependabot in SixLabors/ImageSharp#2142 * Bump actions/upload-artifact from 2 to 3 by @dependabot in SixLabors/ImageSharp#2146 * Bump codecov/codecov-action from 1 to 3 by @dependabot in SixLabors/ImageSharp#2144 * Skip invalid markers during jpeg decoding by @br3aker in SixLabors/ImageSharp#2147 * Tiff: Performance improvements for Fax4 decompression by @brianpopow in SixLabors/ImageSharp#2134 * Fix regression in TIF image loading by @brianpopow in SixLabors/ImageSharp#2150 * Used inline SIMD vectors if they are constants by @gfoidl in SixLabors/ImageSharp#2122 * Print environment info on tests start by @JimBobSquarePants in SixLabors/ImageSharp#2175 * Update License by @JimBobSquarePants in SixLabors/ImageSharp#2176 * Jpeg downscaling decoding by @br3aker in SixLabors/ImageSharp#2076 * Add support for decoding tiff images with CieLab color space by @brianpopow in SixLabors/ImageSharp#2127 * Assembly Trimming Support by @ds5678 in SixLabors/ImageSharp#2160 * Jpeg color space deduction fix by @br3aker in SixLabors/ImageSharp#2177 * Add support for decoding tiff with webp compressed data by @brianpopow in SixLabors/ImageSharp#2128 * Fix issue when writing lossy webp with alpha data by @brianpopow in SixLabors/ImageSharp#2173 * Fix run-length encode compression implementation mistake in tga encoder by @l1nxy in SixLabors/ImageSharp#2172 * TGA Encoder/Decoder Improvements by @brianpopow in SixLabors/ImageSharp#2197 * Tiff: Make sure 1 Bit compression is only used with 1 bit pixel type by @brianpopow in SixLabors/ImageSharp#2201 * Refactor `EnumUtils` and make it AOT-friendly. by @teo-tsirpanis in SixLabors/ImageSharp#2200 * Jpeg encoder complete rewrite by @br3aker in SixLabors/ImageSharp#2120 * Fix IPTC tags written on jpg files that contains non-English characters can't be correctly displayed on external apps #2212 by @lmerino-ep in SixLabors/ImageSharp#2213 * Identify transparency for indexed PNG correctly by @brianpopow in SixLabors/ImageSharp#2215 * Introduce Shared General Decoder Options plus Specialization by @JimBobSquarePants in SixLabors/ImageSharp#2180 * Add option to encode 2-bit Bitmap's by @brianpopow in SixLabors/ImageSharp#2220 * Fix AdaptiveThresholdProcessor throws IndexOutOfRangeException by @brianpopow in SixLabors/ImageSharp#2221 * Relaxed bmp dimensions validation by @smorokin in SixLabors/ImageSharp#2192 * Remove obsolete code by @JimBobSquarePants in SixLabors/ImageSharp#2189 * Implement Median Blur processor by @ynse01 in SixLabors/ImageSharp#2219 * Make TestFile Image threadsafe. by @JimBobSquarePants in SixLabors/ImageSharp#2225 * PNG filter improvements by @saucecontrol in SixLabors/ImageSharp#2226 * Use File-Scoped Namespaces and Global Implicit Usings by @JimBobSquarePants in SixLabors/ImageSharp#2229 * Fix for issue #2117 by @brianpopow in SixLabors/ImageSharp#2230 * Use System.Half for HalfTypeHelper by @JimBobSquarePants in SixLabors/ImageSharp#2233 * [Chore] Remove InlineningOption from ThrowHelpers by @blouflashdb in SixLabors/ImageSharp#2234 * Implement AutoLevel processor - Attempt 2 by @ynse01 in SixLabors/ImageSharp#2235 * Add TryGetLinearlySeparableComponents and tests by @JimBobSquarePants in SixLabors/ImageSharp#2224 ... (truncated) ## 2.1.13 ## What's Changed * V2 backport: 2243 - Ignore unknown chunks for WEBP by @sonbua in SixLabors/ImageSharp#2505 ## New Contributors * @sonbua made their first contribution in SixLabors/ImageSharp#2505 **Full Changelog**: SixLabors/ImageSharp@v2.1.12...v2.1.13 ## 2.1.12 ## What's Changed * Backport #2926 to release/2.1.x by @mus65 in SixLabors/ImageSharp#2985 ## New Contributors * @mus65 made their first contribution in SixLabors/ImageSharp#2985 **Full Changelog**: SixLabors/ImageSharp@v2.1.11...v2.1.12 ## 2.1.11 ## What's Changed * Backport V2 - GIF: Check for end of stream when reading comments. by @JimBobSquarePants in SixLabors/ImageSharp#2971 **Full Changelog**: SixLabors/ImageSharp@v2.1.10...v2.1.11 ## 2.1.10 ## What's Changed * Backport #2859 to release/2.1.x by @antonfirsov in SixLabors/ImageSharp#2890 * Backport #2701 to 2.1.x [copy] by @antonfirsov in SixLabors/ImageSharp#2891 **Full Changelog**: SixLabors/ImageSharp@v2.1.9...v2.1.10 Commits viewable in [compare view](SixLabors/ImageSharp@v2.1.9...v4.1.2). </details> [![Dependabot compatibility score](https://dependabot-badges.githubapp.com/badges/compatibility_score?dependency-name=SixLabors.ImageSharp&package-manager=nuget&previous-version=2.1.9&new-version=4.1.2)](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. 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Vectorize TrimTransparentPixels in GifEncoderCore

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gfoidl mentioned this pull request Jul 27, 2023

Preserve Gif color palettes and deduplicate frame pixels. #2455

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gfoidl commented Jul 27, 2023

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JimBobSquarePants merged commit 949e6ad into SixLabors:js/gif-fixes Aug 9, 2023

gfoidl deleted the git-transparency-simd branch August 9, 2023 12:14

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Vectorize TrimTransparentPixels in GifEncoderCore - #2500

Vectorize TrimTransparentPixels in GifEncoderCore#2500
JimBobSquarePants merged 2 commits into
SixLabors:js/gif-fixesfrom
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