mirror of https://github.com/SixLabors/ImageSharp
James Jackson-South
6 years ago
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GitHub
GitHub
33 changed files with 704 additions and 625 deletions
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// Copyright (c) Six Labors and contributors.
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// Licensed under the Apache License, Version 2.0.
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using System; |
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using SixLabors.ImageSharp.PixelFormats; |
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namespace SixLabors.ImageSharp.Processing.Processors.Dithering |
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{ |
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/// <summary>
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/// Implements an algorithm to alter the pixels of an image via palette dithering.
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/// </summary>
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/// <typeparam name="TPixel">The pixel format.</typeparam>
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public interface IPaletteDitherImageProcessor<TPixel> |
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where TPixel : unmanaged, IPixel<TPixel> |
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{ |
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/// <summary>
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/// Gets the configuration instance to use when performing operations.
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/// </summary>
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Configuration Configuration { get; } |
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/// <summary>
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/// Gets the dithering palette.
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/// </summary>
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ReadOnlyMemory<TPixel> Palette { get; } |
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/// <summary>
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/// Gets the dithering scale used to adjust the amount of dither. Range 0..1.
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/// </summary>
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float DitherScale { get; } |
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/// <summary>
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/// Returns the color from the dithering palette corresponding to the given color.
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/// </summary>
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/// <param name="color">The color to match.</param>
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/// <returns>The <typeparamref name="TPixel"/> match.</returns>
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TPixel GetPaletteColor(TPixel color); |
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} |
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} |
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// Copyright (c) Six Labors and contributors.
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// Licensed under the Apache License, Version 2.0.
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using System; |
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using SixLabors.ImageSharp.PixelFormats; |
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namespace SixLabors.ImageSharp.Processing.Processors.Quantization |
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{ |
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/// <summary>
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/// Allows the mapping of input colors to colors within a given palette.
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/// TODO: Expose this somehow.
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/// </summary>
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/// <typeparam name="TPixel">The pixel format.</typeparam>
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internal interface IPixelMap<TPixel> |
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where TPixel : unmanaged, IPixel<TPixel> |
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{ |
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/// <summary>
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/// Gets the color palette containing colors to match.
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/// </summary>
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ReadOnlyMemory<TPixel> Palette { get; } |
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/// <summary>
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/// Returns the closest color in the palette and the index of that pixel.
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/// </summary>
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/// <param name="color">The color to match.</param>
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/// <param name="match">The matched color.</param>
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/// <returns>The <see cref="int"/> index.</returns>
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int GetClosestColor(TPixel color, out TPixel match); |
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} |
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} |
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// Copyright (c) Six Labors and contributors.
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// Licensed under the Apache License, Version 2.0.
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using System; |
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using System.Buffers; |
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using System.Runtime.CompilerServices; |
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using SixLabors.ImageSharp.Memory; |
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using SixLabors.ImageSharp.PixelFormats; |
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namespace SixLabors.ImageSharp.Processing.Processors.Quantization |
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{ |
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/// <summary>
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/// A pixel-specific image frame where each pixel buffer value represents an index in a color palette.
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/// </summary>
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/// <typeparam name="TPixel">The pixel format.</typeparam>
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public sealed class IndexedImageFrame<TPixel> : IDisposable |
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where TPixel : unmanaged, IPixel<TPixel> |
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{ |
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private IMemoryOwner<byte> pixelsOwner; |
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private IMemoryOwner<TPixel> paletteOwner; |
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private bool isDisposed; |
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/// <summary>
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/// Initializes a new instance of the <see cref="IndexedImageFrame{TPixel}"/> class.
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/// </summary>
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/// <param name="configuration">
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/// The configuration which allows altering default behaviour or extending the library.
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/// </param>
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/// <param name="width">The frame width.</param>
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/// <param name="height">The frame height.</param>
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/// <param name="palette">The color palette.</param>
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internal IndexedImageFrame(Configuration configuration, int width, int height, ReadOnlyMemory<TPixel> palette) |
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{ |
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Guard.NotNull(configuration, nameof(configuration)); |
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Guard.MustBeLessThanOrEqualTo(palette.Length, QuantizerConstants.MaxColors, nameof(palette)); |
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Guard.MustBeGreaterThan(width, 0, nameof(width)); |
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Guard.MustBeGreaterThan(height, 0, nameof(height)); |
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this.Configuration = configuration; |
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this.Width = width; |
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this.Height = height; |
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this.pixelsOwner = configuration.MemoryAllocator.AllocateManagedByteBuffer(width * height); |
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// Copy the palette over. We want the lifetime of this frame to be independant of any palette source.
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this.paletteOwner = configuration.MemoryAllocator.Allocate<TPixel>(palette.Length); |
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palette.Span.CopyTo(this.paletteOwner.GetSpan()); |
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this.Palette = this.paletteOwner.Memory.Slice(0, palette.Length); |
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} |
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/// <summary>
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/// Gets the configuration which allows altering default behaviour or extending the library.
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/// </summary>
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public Configuration Configuration { get; } |
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/// <summary>
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/// Gets the width of this <see cref="IndexedImageFrame{TPixel}"/>.
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/// </summary>
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public int Width { get; } |
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/// <summary>
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/// Gets the height of this <see cref="IndexedImageFrame{TPixel}"/>.
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/// </summary>
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public int Height { get; } |
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/// <summary>
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/// Gets the color palette of this <see cref="IndexedImageFrame{TPixel}"/>.
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/// </summary>
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public ReadOnlyMemory<TPixel> Palette { get; } |
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/// <summary>
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/// Gets the pixels of this <see cref="IndexedImageFrame{TPixel}"/>.
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/// </summary>
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/// <returns>The <see cref="ReadOnlySpan{T}"/></returns>
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[MethodImpl(InliningOptions.ShortMethod)] |
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public ReadOnlySpan<byte> GetPixelBufferSpan() => this.pixelsOwner.GetSpan(); // TODO: Buffer2D<byte>
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/// <summary>
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/// Gets the representation of the pixels as a <see cref="ReadOnlySpan{T}"/> of contiguous memory
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/// at row <paramref name="rowIndex"/> beginning from the the first pixel on that row.
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/// </summary>
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/// <param name="rowIndex">The row index in the pixel buffer.</param>
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/// <returns>The pixel row as a <see cref="ReadOnlySpan{T}"/>.</returns>
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[MethodImpl(InliningOptions.ShortMethod)] |
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public ReadOnlySpan<byte> GetPixelRowSpan(int rowIndex) |
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=> this.GetWritablePixelRowSpanUnsafe(rowIndex); |
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/// <summary>
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/// <para>
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/// Gets the representation of the pixels as a <see cref="Span{T}"/> of contiguous memory
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/// at row <paramref name="rowIndex"/> beginning from the the first pixel on that row.
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/// </para>
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/// <para>
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/// Note: Values written to this span are not sanitized against the palette length.
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/// Care should be taken during assignment to prevent out-of-bounds errors.
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/// </para>
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/// </summary>
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/// <param name="rowIndex">The row index in the pixel buffer.</param>
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/// <returns>The pixel row as a <see cref="Span{T}"/>.</returns>
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[MethodImpl(InliningOptions.ShortMethod)] |
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public Span<byte> GetWritablePixelRowSpanUnsafe(int rowIndex) |
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=> this.pixelsOwner.GetSpan().Slice(rowIndex * this.Width, this.Width); |
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/// <inheritdoc/>
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public void Dispose() |
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{ |
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if (!this.isDisposed) |
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{ |
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this.isDisposed = true; |
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this.pixelsOwner.Dispose(); |
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this.paletteOwner.Dispose(); |
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this.pixelsOwner = null; |
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this.paletteOwner = null; |
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} |
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} |
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} |
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} |
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@ -1,91 +0,0 @@ |
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// Copyright (c) Six Labors and contributors.
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// Licensed under the Apache License, Version 2.0.
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using System; |
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using System.Buffers; |
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using System.Runtime.CompilerServices; |
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using SixLabors.ImageSharp.Memory; |
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using SixLabors.ImageSharp.PixelFormats; |
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namespace SixLabors.ImageSharp.Processing.Processors.Quantization |
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{ |
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/// <summary>
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/// Represents a quantized image frame where the pixels indexed by a color palette.
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/// </summary>
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/// <typeparam name="TPixel">The pixel format.</typeparam>
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public sealed class QuantizedFrame<TPixel> : IDisposable |
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where TPixel : unmanaged, IPixel<TPixel> |
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{ |
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private IMemoryOwner<byte> pixels; |
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private bool isDisposed; |
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/// <summary>
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/// Initializes a new instance of the <see cref="QuantizedFrame{TPixel}"/> class.
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/// </summary>
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/// <param name="memoryAllocator">Used to allocated memory for image processing operations.</param>
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/// <param name="width">The image width.</param>
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/// <param name="height">The image height.</param>
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/// <param name="palette">The color palette.</param>
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internal QuantizedFrame(MemoryAllocator memoryAllocator, int width, int height, ReadOnlyMemory<TPixel> palette) |
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{ |
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Guard.MustBeGreaterThan(width, 0, nameof(width)); |
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Guard.MustBeGreaterThan(height, 0, nameof(height)); |
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this.Width = width; |
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this.Height = height; |
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this.Palette = palette; |
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this.pixels = memoryAllocator.AllocateManagedByteBuffer(width * height, AllocationOptions.Clean); |
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} |
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/// <summary>
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/// Gets the width of this <see cref="QuantizedFrame{TPixel}"/>.
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/// </summary>
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public int Width { get; } |
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/// <summary>
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/// Gets the height of this <see cref="QuantizedFrame{TPixel}"/>.
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/// </summary>
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public int Height { get; } |
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/// <summary>
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/// Gets the color palette of this <see cref="QuantizedFrame{TPixel}"/>.
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/// </summary>
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public ReadOnlyMemory<TPixel> Palette { get; private set; } |
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/// <summary>
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/// Gets the pixels of this <see cref="QuantizedFrame{TPixel}"/>.
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/// </summary>
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/// <returns>The <see cref="Span{T}"/></returns>
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[MethodImpl(InliningOptions.ShortMethod)] |
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public ReadOnlySpan<byte> GetPixelSpan() => this.pixels.GetSpan(); |
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/// <summary>
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/// Gets the representation of the pixels as a <see cref="Span{T}"/> of contiguous memory
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/// at row <paramref name="rowIndex"/> beginning from the the first pixel on that row.
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/// </summary>
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/// <param name="rowIndex">The row.</param>
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/// <returns>The pixel row as a <see cref="ReadOnlySpan{T}"/>.</returns>
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[MethodImpl(InliningOptions.ShortMethod)] |
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public ReadOnlySpan<byte> GetRowSpan(int rowIndex) |
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=> this.GetPixelSpan().Slice(rowIndex * this.Width, this.Width); |
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/// <inheritdoc/>
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public void Dispose() |
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{ |
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if (this.isDisposed) |
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{ |
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return; |
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} |
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this.isDisposed = true; |
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this.pixels?.Dispose(); |
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this.pixels = null; |
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this.Palette = null; |
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} |
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/// <summary>
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/// Get the non-readonly memory of pixel data so <see cref="IFrameQuantizer{TPixel}"/> can fill it.
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/// </summary>
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internal Memory<byte> GetWritablePixelMemory() => this.pixels.Memory; |
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} |
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} |
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@ -1 +1 @@ |
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Subproject commit f8a76fd3a900b90c98df67ac896574383a4d09f3 |
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Subproject commit 1fea1ceab89e87cc5f11376fa46164d3d27566c0 |
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