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Use quality and method from options in Vp8Encoder

pull/1552/head
Brian Popow 5 years ago
parent
7e23212ba1
commit
0807ede3be
2 changed files with 41 additions and 14 deletions
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  1. 53
      src/ImageSharp/Formats/WebP/Lossy/Vp8Encoder.cs
  2. 2
      src/ImageSharp/Formats/WebP/WebPEncoderCore.cs

53
src/ImageSharp/Formats/WebP/Lossy/Vp8Encoder.cs
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@ -27,6 +27,16 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
/// </summary>
private readonly Vp8BitWriter bitWriter;
/// <summary>
/// The quality, that will be used to encode the image.
/// </summary>
private readonly int quality;
/// <summary>
/// Quality/speed trade-off (0=fast, 6=slower-better).
/// </summary>
private readonly int method;
/// <summary>
/// Fixed-point precision for RGB->YUV.
/// </summary>
@ -42,7 +52,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
private const int QFix = 17;
private readonly byte[] zigzag = new byte[] { 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15 };
private readonly byte[] zigzag = { 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15 };
private readonly byte[] averageBytesPerMb = { 50, 24, 16, 9, 7, 5, 3, 2 };
@ -52,9 +62,13 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
/// <param name="memoryAllocator">The memory allocator.</param>
/// <param name="width">The width of the input image.</param>
/// <param name="height">The height of the input image.</param>
public Vp8Encoder(MemoryAllocator memoryAllocator, int width, int height)
/// <param name="quality">The encoding quality.</param>
/// <param name="method">Quality/speed trade-off (0=fast, 6=slower-better).</param>
public Vp8Encoder(MemoryAllocator memoryAllocator, int width, int height, int quality, int method)
{
this.memoryAllocator = memoryAllocator;
this.quality = quality.Clamp(0, 100);
this.method = method.Clamp(0, 6);
var pixelCount = width * height;
int mbw = (width + 15) >> 4;
@ -81,10 +95,19 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
/// </summary>
public int Alpha { get; set; }
/// <summary>
/// Gets the luma component.
/// </summary>
private IMemoryOwner<byte> Y { get; }
/// <summary>
/// Gets the chroma U component.
/// </summary>
private IMemoryOwner<byte> U { get; }
/// <summary>
/// Gets the chroma U component.
/// </summary>
private IMemoryOwner<byte> V { get; }
/// <summary>
@ -112,6 +135,12 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
/// </summary>
private int MbHeaderLimit { get; }
/// <summary>
/// Encodes the image to the specified stream from the <see cref="Image{TPixel}"/>.
/// </summary>
/// <typeparam name="TPixel">The pixel format.</typeparam>
/// <param name="image">The <see cref="Image{TPixel}"/> to encode from.</param>
/// <param name="stream">The <see cref="Stream"/> to encode the image data to.</param>
public void Encode<TPixel>(Image<TPixel> image, Stream stream)
where TPixel : unmanaged, IPixel<TPixel>
{
@ -139,10 +168,8 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
}
var it = new Vp8EncIterator(this.YTop, this.UvTop, this.Preds, this.Nz, mb, mbw, mbh);
int method = 4; // TODO: hardcoded for now
int quality = 100; // TODO: hardcoded for now
var alphas = new int[WebPConstants.MaxAlpha + 1];
int alpha = this.MacroBlockAnalysis(width, height, it, y, u, v, yStride, uvStride, method, quality, alphas, out int uvAlpha);
int alpha = this.MacroBlockAnalysis(width, height, it, y, u, v, yStride, uvStride, alphas, out int uvAlpha);
// Analysis is done, proceed to actual coding.
@ -156,7 +183,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
{
var info = new Vp8ModeScore();
it.Import(y, u, v, yStride, uvStride, width, height);
if (!this.Decimate(it, segmentInfos, info, method))
if (!this.Decimate(it, segmentInfos, info))
{
this.CodeResiduals(it, info);
}
@ -196,7 +223,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
// TODO: SetupMatrices
}
private int MacroBlockAnalysis(int width, int height, Vp8EncIterator it, Span<byte> y, Span<byte> u, Span<byte> v, int yStride, int uvStride, int method, int quality, int[] alphas, out int uvAlpha)
private int MacroBlockAnalysis(int width, int height, Vp8EncIterator it, Span<byte> y, Span<byte> u, Span<byte> v, int yStride, int uvStride, int[] alphas, out int uvAlpha)
{
int alpha = 0;
uvAlpha = 0;
@ -205,7 +232,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
do
{
it.Import(y, u, v, yStride, uvStride, width, height);
int bestAlpha = this.MbAnalyze(it, method, quality, alphas, out var bestUvAlpha);
int bestAlpha = this.MbAnalyze(it, alphas, out var bestUvAlpha);
// Accumulate for later complexity analysis.
alpha += bestAlpha;
@ -217,16 +244,16 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
return alpha;
}
private int MbAnalyze(Vp8EncIterator it, int method, int quality, int[] alphas, out int bestUvAlpha)
private int MbAnalyze(Vp8EncIterator it, int[] alphas, out int bestUvAlpha)
{
it.SetIntra16Mode(0); // default: Intra16, DC_PRED
it.SetSkip(false); // not skipped.
it.SetSegment(0); // default segment, spec-wise.
int bestAlpha;
if (method <= 1)
if (this.method <= 1)
{
bestAlpha = it.FastMbAnalyze(quality);
bestAlpha = it.FastMbAnalyze(this.quality);
}
else
{
@ -244,7 +271,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
return bestAlpha; // Mixed susceptibility (not just luma).
}
private bool Decimate(Vp8EncIterator it, Vp8SegmentInfo[] segmentInfos, Vp8ModeScore rd, int method)
private bool Decimate(Vp8EncIterator it, Vp8SegmentInfo[] segmentInfos, Vp8ModeScore rd)
{
rd.InitScore();
@ -256,7 +283,7 @@ namespace SixLabors.ImageSharp.Formats.WebP.Lossy
// For method >= 2, pick the best intra4/intra16 based on SSE (~tad slower).
// For method <= 1, we don't re-examine the decision but just go ahead with
// quantization/reconstruction.
this.RefineUsingDistortion(it, segmentInfos, rd, method >= 2, method >= 1);
this.RefineUsingDistortion(it, segmentInfos, rd, this.method >= 2, this.method >= 1);
bool isSkipped = rd.Nz == 0;
it.SetSkip(isSkipped);

2
src/ImageSharp/Formats/WebP/WebPEncoderCore.cs
View File

@ -79,7 +79,7 @@ namespace SixLabors.ImageSharp.Formats.WebP
if (this.lossy)
{
var enc = new Vp8Encoder(this.memoryAllocator, image.Width, image.Height);
var enc = new Vp8Encoder(this.memoryAllocator, image.Width, image.Height, this.quality, this.method);
enc.Encode(image, stream);
}
else

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