tsai
/
ImageSharp
mirror of https://github.com/SixLabors/ImageSharp
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

Use separate buffer for encoded image data and input bgra data

pull/1552/head
Brian Popow 5 years ago
parent
ea911998ef
commit
1fe943a9fa
1 changed files with 38 additions and 24 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Unified View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 62
      src/ImageSharp/Formats/WebP/Lossless/Vp8LEncoder.cs

62
src/ImageSharp/Formats/WebP/Lossless/Vp8LEncoder.cs
View File

@ -80,6 +80,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
this.method = Numerics.Clamp(method, 0, 6); this.method = Numerics.Clamp(method, 0, 6);
this.bitWriter = new Vp8LBitWriter(initialSize); this.bitWriter = new Vp8LBitWriter(initialSize);
this.Bgra = memoryAllocator.Allocate<uint>(pixelCount); this.Bgra = memoryAllocator.Allocate<uint>(pixelCount);
this.EncodedData = memoryAllocator.Allocate<uint>(pixelCount);
this.Palette = memoryAllocator.Allocate<uint>(WebpConstants.MaxPaletteSize); this.Palette = memoryAllocator.Allocate<uint>(WebpConstants.MaxPaletteSize);
this.Refs = new Vp8LBackwardRefs[3]; this.Refs = new Vp8LBackwardRefs[3];
this.HashChain = new Vp8LHashChain(pixelCount); this.HashChain = new Vp8LHashChain(pixelCount);
@ -96,10 +97,15 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
} }
/// <summary> /// <summary>
/// Gets the memory for the encoded output image data. /// Gets the memory for the image data as packed bgra values.
/// </summary> /// </summary>
public IMemoryOwner<uint> Bgra { get; } public IMemoryOwner<uint> Bgra { get; }
/// <summary>
/// Gets the memory for the encoded output image data.
/// </summary>
public IMemoryOwner<uint> EncodedData { get; }
/// <summary> /// <summary>
/// Gets or sets the scratch memory for bgra rows used for predictions. /// Gets or sets the scratch memory for bgra rows used for predictions.
/// </summary> /// </summary>
@ -237,7 +243,8 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
// Convert image pixels to bgra array. // Convert image pixels to bgra array.
this.ConvertPixelsToBgra(image, width, height); this.ConvertPixelsToBgra(image, width, height);
Span<uint> bgra = this.Bgra.GetSpan(); ReadOnlySpan<uint> bgra = this.Bgra.GetSpan();
Span<uint> encodedData = this.EncodedData.GetSpan();
// Analyze image (entropy, numPalettes etc). // Analyze image (entropy, numPalettes etc).
CrunchConfig[] crunchConfigs = this.EncoderAnalyze(bgra, width, height, out bool redAndBlueAlwaysZero); CrunchConfig[] crunchConfigs = this.EncoderAnalyze(bgra, width, height, out bool redAndBlueAlwaysZero);
@ -248,6 +255,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
bool isFirstConfig = true; bool isFirstConfig = true;
foreach (CrunchConfig crunchConfig in crunchConfigs) foreach (CrunchConfig crunchConfig in crunchConfigs)
{ {
bgra.CopyTo(encodedData);
bool useCache = true; bool useCache = true;
this.UsePalette = crunchConfig.EntropyIdx == EntropyIx.Palette || this.UsePalette = crunchConfig.EntropyIdx == EntropyIx.Palette ||
crunchConfig.EntropyIdx == EntropyIx.PaletteAndSpatial; crunchConfig.EntropyIdx == EntropyIx.PaletteAndSpatial;
@ -297,15 +305,11 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
// Encode and write the transformed image. // Encode and write the transformed image.
this.EncodeImage( this.EncodeImage(
bgra,
this.HashChain,
this.Refs,
this.CurrentWidth, this.CurrentWidth,
height, height,
useCache, useCache,
crunchConfig, crunchConfig,
this.CacheBits, this.CacheBits);
this.HistoBits);
// If we are better than what we already have. // If we are better than what we already have.
if (isFirstConfig || this.bitWriter.NumBytes() < bestSize) if (isFirstConfig || this.bitWriter.NumBytes() < bestSize)
@ -421,9 +425,11 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
return crunchConfigs.ToArray(); return crunchConfigs.ToArray();
} }
private void EncodeImage(ReadOnlySpan<uint> bgra, Vp8LHashChain hashChain, Vp8LBackwardRefs[] refsArray, int width, int height, bool useCache, CrunchConfig config, int cacheBits, int histogramBits) private void EncodeImage(int width, int height, bool useCache, CrunchConfig config, int cacheBits)
{ {
int histogramImageXySize = LosslessUtils.SubSampleSize(width, histogramBits) * LosslessUtils.SubSampleSize(height, histogramBits); // bgra data with transformations applied.
Span<uint> bgra = this.EncodedData.GetSpan();
int histogramImageXySize = LosslessUtils.SubSampleSize(width, this.HistoBits) * LosslessUtils.SubSampleSize(height, this.HistoBits);
ushort[] histogramSymbols = new ushort[histogramImageXySize]; ushort[] histogramSymbols = new ushort[histogramImageXySize];
var huffTree = new HuffmanTree[3 * WebpConstants.CodeLengthCodes]; var huffTree = new HuffmanTree[3 * WebpConstants.CodeLengthCodes];
for (int i = 0; i < huffTree.Length; i++) for (int i = 0; i < huffTree.Length; i++)
@ -444,7 +450,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
} }
// Calculate backward references from BGRA image. // Calculate backward references from BGRA image.
hashChain.Fill(this.memoryAllocator, bgra, this.quality, width, height); this.HashChain.Fill(this.memoryAllocator, bgra, this.quality, width, height);
Vp8LBitWriter bitWriterBest = config.SubConfigs.Count > 1 ? this.bitWriter.Clone() : this.bitWriter; Vp8LBitWriter bitWriterBest = config.SubConfigs.Count > 1 ? this.bitWriter.Clone() : this.bitWriter;
Vp8LBitWriter bwInit = this.bitWriter; Vp8LBitWriter bwInit = this.bitWriter;
@ -458,13 +464,13 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
this.quality, this.quality,
subConfig.Lz77, subConfig.Lz77,
ref cacheBits, ref cacheBits,
hashChain, this.HashChain,
refsArray[0], this.Refs[0],
refsArray[1]); // TODO : Pass do not cache this.Refs[1]);
// Keep the best references aside and use the other element from the first // Keep the best references aside and use the other element from the first
// two as a temporary for later usage. // two as a temporary for later usage.
Vp8LBackwardRefs refsTmp = refsArray[refsBest.Equals(refsArray[0]) ? 1 : 0]; Vp8LBackwardRefs refsTmp = this.Refs[refsBest.Equals(this.Refs[0]) ? 1 : 0];
this.bitWriter.Reset(bwInit); this.bitWriter.Reset(bwInit);
var tmpHisto = new Vp8LHistogram(cacheBits); var tmpHisto = new Vp8LHistogram(cacheBits);
@ -475,7 +481,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
} }
// Build histogram image and symbols from backward references. // Build histogram image and symbols from backward references.
HistogramEncoder.GetHistoImageSymbols(width, height, refsBest, this.quality, histogramBits, cacheBits, histogramImage, tmpHisto, histogramSymbols); HistogramEncoder.GetHistoImageSymbols(width, height, refsBest, this.quality, this.HistoBits, cacheBits, histogramImage, tmpHisto, histogramSymbols);
// Create Huffman bit lengths and codes for each histogram image. // Create Huffman bit lengths and codes for each histogram image.
int histogramImageSize = histogramImage.Count; int histogramImageSize = histogramImage.Count;
@ -517,8 +523,15 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
} }
} }
this.bitWriter.PutBits((uint)(histogramBits - 2), 3); this.bitWriter.PutBits((uint)(this.HistoBits - 2), 3);
this.EncodeImageNoHuffman(histogramBgra, hashChain, refsTmp, refsArray[2], LosslessUtils.SubSampleSize(width, histogramBits), LosslessUtils.SubSampleSize(height, histogramBits), this.quality); this.EncodeImageNoHuffman(
histogramBgra,
this.HashChain,
refsTmp,
this.Refs[2],
LosslessUtils.SubSampleSize(width, this.HistoBits),
LosslessUtils.SubSampleSize(height, this.HistoBits),
this.quality);
} }
// Store Huffman codes. // Store Huffman codes.
@ -547,12 +560,12 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
} }
// Store actual literals. // Store actual literals.
this.StoreImageToBitMask(width, histogramBits, refsBest, histogramSymbols, huffmanCodes); this.StoreImageToBitMask(width, this.HistoBits, refsBest, histogramSymbols, huffmanCodes);
// Keep track of the smallest image so far. // Keep track of the smallest image so far.
if (isFirstIteration || (bitWriterBest != null && this.bitWriter.NumBytes() < bitWriterBest.NumBytes())) if (isFirstIteration || (bitWriterBest != null && this.bitWriter.NumBytes() < bitWriterBest.NumBytes()))
{ {
// TODO: This was done in the reference by swapping references, this will be slower // TODO: This was done in the reference by swapping references, this will be slower.
bitWriterBest = this.bitWriter.Clone(); bitWriterBest = this.bitWriter.Clone();
} }
@ -589,7 +602,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
{ {
this.bitWriter.PutBits(WebpConstants.TransformPresent, 1); this.bitWriter.PutBits(WebpConstants.TransformPresent, 1);
this.bitWriter.PutBits((uint)Vp8LTransformType.SubtractGreen, 2); this.bitWriter.PutBits((uint)Vp8LTransformType.SubtractGreen, 2);
LosslessUtils.SubtractGreenFromBlueAndRed(this.Bgra.GetSpan()); LosslessUtils.SubtractGreenFromBlueAndRed(this.EncodedData.GetSpan());
} }
private void ApplyPredictFilter(int width, int height, bool usedSubtractGreen) private void ApplyPredictFilter(int width, int height, bool usedSubtractGreen)
@ -600,7 +613,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
int transformWidth = LosslessUtils.SubSampleSize(width, predBits); int transformWidth = LosslessUtils.SubSampleSize(width, predBits);
int transformHeight = LosslessUtils.SubSampleSize(height, predBits); int transformHeight = LosslessUtils.SubSampleSize(height, predBits);
PredictorEncoder.ResidualImage(width, height, predBits, this.Bgra.GetSpan(), this.BgraScratch.GetSpan(), this.TransformData.GetSpan(), nearLosslessStrength, exact, usedSubtractGreen); PredictorEncoder.ResidualImage(width, height, predBits, this.EncodedData.GetSpan(), this.BgraScratch.GetSpan(), this.TransformData.GetSpan(), nearLosslessStrength, exact, usedSubtractGreen);
this.bitWriter.PutBits(WebpConstants.TransformPresent, 1); this.bitWriter.PutBits(WebpConstants.TransformPresent, 1);
this.bitWriter.PutBits((uint)Vp8LTransformType.PredictorTransform, 2); this.bitWriter.PutBits((uint)Vp8LTransformType.PredictorTransform, 2);
@ -615,7 +628,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
int transformWidth = LosslessUtils.SubSampleSize(width, colorTransformBits); int transformWidth = LosslessUtils.SubSampleSize(width, colorTransformBits);
int transformHeight = LosslessUtils.SubSampleSize(height, colorTransformBits); int transformHeight = LosslessUtils.SubSampleSize(height, colorTransformBits);
PredictorEncoder.ColorSpaceTransform(width, height, colorTransformBits, this.quality, this.Bgra.GetSpan(), this.TransformData.GetSpan()); PredictorEncoder.ColorSpaceTransform(width, height, colorTransformBits, this.quality, this.EncodedData.GetSpan(), this.TransformData.GetSpan());
this.bitWriter.PutBits(WebpConstants.TransformPresent, 1); this.bitWriter.PutBits(WebpConstants.TransformPresent, 1);
this.bitWriter.PutBits((uint)Vp8LTransformType.CrossColorTransform, 2); this.bitWriter.PutBits((uint)Vp8LTransformType.CrossColorTransform, 2);
@ -1161,9 +1174,9 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
private void MapImageFromPalette(int width, int height) private void MapImageFromPalette(int width, int height)
{ {
Span<uint> src = this.Bgra.GetSpan(); Span<uint> src = this.EncodedData.GetSpan();
int srcStride = this.CurrentWidth; int srcStride = this.CurrentWidth;
Span<uint> dst = this.Bgra.GetSpan(); // Applying the palette will be done in place. Span<uint> dst = this.EncodedData.GetSpan(); // Applying the palette will be done in place.
Span<uint> palette = this.Palette.GetSpan(); Span<uint> palette = this.Palette.GetSpan();
int paletteSize = this.PaletteSize; int paletteSize = this.PaletteSize;
int xBits; int xBits;
@ -1698,6 +1711,7 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
public void Dispose() public void Dispose()
{ {
this.Bgra.Dispose(); this.Bgra.Dispose();
this.EncodedData.Dispose();
this.BgraScratch.Dispose(); this.BgraScratch.Dispose();
this.Palette.Dispose(); this.Palette.Dispose();
this.TransformData.Dispose(); this.TransformData.Dispose();

Write Preview
Loading…
Cancel
Save