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

Remove allocation when upscaling.

af/merge-core
James Jackson-South 8 years ago
parent
e808514648
commit
8f37a41d58
2 changed files with 152 additions and 149 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 296
      src/ImageSharp/Formats/Png/PngDecoderCore.cs
  2. 5
      tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.cs

296
src/ImageSharp/Formats/Png/PngDecoderCore.cs
View File

@ -341,25 +341,36 @@ namespace SixLabors.ImageSharp.Formats.Png
}
/// <summary>
/// Converts a byte array to a new array where each value in the original array is represented by the specified number of bits.
/// Reads the least significant bits from the byte pair with the others set to 0.
/// </summary>
/// <param name="buffer">The source buffer</param>
/// <param name="offset">THe offset</param>
/// <returns>The <see cref="int"/></returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static byte ReadByteLittleEndian(ReadOnlySpan<byte> buffer, int offset)
{
return (byte)(((buffer[offset] & 0xFF) << 16) | (buffer[offset + 1] & 0xFF));
}
/// <summary>
/// Attempts to convert a byte array to a new array where each value in the original array is represented by the
/// specified number of bits.
/// </summary>
/// <param name="source">The bytes to convert from. Cannot be empty.</param>
/// <param name="bytesPerScanline">The number of bytes per scanline</param>
/// <param name="bits">The number of bits per value.</param>
/// <param name="buffer">The new array.</param>
/// <returns>The resulting <see cref="ReadOnlySpan{Byte}"/> array.</returns>
/// <exception cref="System.ArgumentException"><paramref name="bits"/> is less than or equals than zero.</exception>
private static ReadOnlySpan<byte> ToArrayByBitsLength(ReadOnlySpan<byte> source, int bytesPerScanline, int bits)
private bool TryScaleUpTo8BitArray(ReadOnlySpan<byte> source, int bytesPerScanline, int bits, out IManagedByteBuffer buffer)
{
Guard.MustBeGreaterThan(source.Length, 0, nameof(source));
Guard.MustBeGreaterThan(bits, 0, nameof(bits));
if (bits >= 8)
{
return source;
buffer = null;
return false;
}
// TODO: We should be pooling this.
byte[] result = new byte[bytesPerScanline * 8 / bits];
buffer = this.MemoryAllocator.AllocateCleanManagedByteBuffer(bytesPerScanline * 8 / bits);
byte[] result = buffer.Array;
int mask = 0xFF >> (8 - bits);
int resultOffset = 0;
@ -369,26 +380,13 @@ namespace SixLabors.ImageSharp.Formats.Png
for (int shift = 0; shift < 8; shift += bits)
{
int colorIndex = (b >> (8 - bits - shift)) & mask;
result[resultOffset] = (byte)colorIndex;
resultOffset++;
}
}
return result;
}
/// <summary>
/// Reads the least significant bits from the byte pair with the others set to 0.
/// </summary>
/// <param name="buffer">The source buffer</param>
/// <param name="offset">THe offset</param>
/// <returns>The <see cref="int"/></returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static byte ReadByteLittleEndian(ReadOnlySpan<byte> buffer, int offset)
{
return (byte)(((buffer[offset] & 0xFF) << 16) | (buffer[offset + 1] & 0xFF));
return true;
}
/// <summary>
@ -669,11 +667,16 @@ namespace SixLabors.ImageSharp.Formats.Png
private void ProcessDefilteredScanline<TPixel>(ReadOnlySpan<byte> defilteredScanline, ImageFrame<TPixel> pixels)
where TPixel : struct, IPixel<TPixel>
{
var color = default(TPixel);
TPixel pixel = default;
Span<TPixel> rowSpan = pixels.GetPixelRowSpan(this.currentRow);
// Trim the first marker byte from the buffer
ReadOnlySpan<byte> scanlineBuffer = defilteredScanline.Slice(1, defilteredScanline.Length - 1);
ReadOnlySpan<byte> trimmed = defilteredScanline.Slice(1, defilteredScanline.Length - 1);
// Convert 1, 2, and 4 bit pixel data into the 8 bit equivalent.
ReadOnlySpan<byte> scanlineSpan = this.TryScaleUpTo8BitArray(trimmed, this.bytesPerScanline, this.header.BitDepth, out IManagedByteBuffer buffer)
? buffer.GetSpan()
: trimmed;
switch (this.pngColorType)
{
@ -681,9 +684,6 @@ namespace SixLabors.ImageSharp.Formats.Png
int factor = 255 / ((int)Math.Pow(2, this.header.BitDepth) - 1);
// Convert 1, 2, and 4 bit pixel data into the 8 bit equivalent.
ReadOnlySpan<byte> scanline = ToArrayByBitsLength(scanlineBuffer, this.bytesPerScanline, this.header.BitDepth);
if (!this.hasTrans)
{
if (this.header.BitDepth == 16)
@ -691,12 +691,12 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgb48 rgb48 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 2)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.R = luminance;
rgb48.G = luminance;
rgb48.B = luminance;
color.PackFromRgb48(rgb48);
rowSpan[x] = color;
pixel.PackFromRgb48(rgb48);
rowSpan[x] = pixel;
}
}
else
@ -705,12 +705,12 @@ namespace SixLabors.ImageSharp.Formats.Png
var rgba32 = new Rgba32(0, 0, 0, byte.MaxValue);
for (int x = 0; x < this.header.Width; x++)
{
byte luminance = (byte)(scanline[x] * factor);
byte luminance = (byte)(scanlineSpan[x] * factor);
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
}
@ -721,14 +721,14 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 2)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgba64.R = luminance;
rgba64.G = luminance;
rgba64.B = luminance;
rgba64.A = luminance.Equals(this.luminance16Trans) ? ushort.MinValue : ushort.MaxValue;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -736,14 +736,14 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba32 rgba32 = default;
for (int x = 0; x < this.header.Width; x++)
{
byte luminance = (byte)(scanline[x] * factor);
byte luminance = (byte)(scanlineSpan[x] * factor);
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
rgba32.A = luminance.Equals(this.luminanceTrans) ? byte.MinValue : byte.MaxValue;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
}
@ -757,15 +757,15 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 4)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort alpha = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
ushort alpha = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgba64.R = luminance;
rgba64.G = luminance;
rgba64.B = luminance;
rgba64.A = alpha;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -774,16 +774,16 @@ namespace SixLabors.ImageSharp.Formats.Png
for (int x = 0; x < this.header.Width; x++)
{
int offset = x * this.bytesPerPixel;
byte luminance = scanlineBuffer[offset];
byte alpha = scanlineBuffer[offset + this.bytesPerSample];
byte luminance = scanlineSpan[offset];
byte alpha = scanlineSpan[offset + this.bytesPerSample];
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
rgba32.A = alpha;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
@ -791,7 +791,7 @@ namespace SixLabors.ImageSharp.Formats.Png
case PngColorType.Palette:
this.ProcessScanlineFromPalette(scanlineBuffer, rowSpan);
this.ProcessScanlineFromPalette(scanlineSpan, rowSpan);
break;
@ -804,16 +804,16 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgb48 rgb48 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 6)
{
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
color.PackFromRgb48(rgb48);
rowSpan[x] = color;
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
pixel.PackFromRgb48(rgb48);
rowSpan[x] = pixel;
}
}
else
{
PixelOperations<TPixel>.Instance.PackFromRgb24Bytes(scanlineBuffer, rowSpan, this.header.Width);
PixelOperations<TPixel>.Instance.PackFromRgb24Bytes(scanlineSpan, rowSpan, this.header.Width);
}
}
else
@ -824,20 +824,20 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 6)
{
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
rgba64.Rgb = rgb48;
rgba64.A = rgb48.Equals(this.rgb48Trans) ? ushort.MinValue : ushort.MaxValue;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
{
ReadOnlySpan<Rgb24> rgb24Span = MemoryMarshal.Cast<byte, Rgb24>(scanlineBuffer);
ReadOnlySpan<Rgb24> rgb24Span = MemoryMarshal.Cast<byte, Rgb24>(scanlineSpan);
for (int x = 0; x < this.header.Width; x++)
{
ref readonly Rgb24 rgb24 = ref rgb24Span[x];
@ -845,8 +845,8 @@ namespace SixLabors.ImageSharp.Formats.Png
rgba32.Rgb = rgb24;
rgba32.A = rgb24.Equals(this.rgb24Trans) ? byte.MinValue : byte.MaxValue;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
}
@ -860,21 +860,23 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = 0, o = 0; x < this.header.Width; x++, o += 8)
{
rgba64.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgba64.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgba64.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
rgba64.A = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 6, 2));
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
rgba64.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgba64.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgba64.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
rgba64.A = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 6, 2));
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
{
PixelOperations<TPixel>.Instance.PackFromRgba32Bytes(scanlineBuffer, rowSpan, this.header.Width);
PixelOperations<TPixel>.Instance.PackFromRgba32Bytes(scanlineSpan, rowSpan, this.header.Width);
}
break;
}
buffer?.Dispose();
}
/// <summary>
@ -888,10 +890,15 @@ namespace SixLabors.ImageSharp.Formats.Png
private void ProcessInterlacedDefilteredScanline<TPixel>(ReadOnlySpan<byte> defilteredScanline, Span<TPixel> rowSpan, int pixelOffset = 0, int increment = 1)
where TPixel : struct, IPixel<TPixel>
{
var color = default(TPixel);
TPixel pixel = default;
// Trim the first marker byte from the buffer
ReadOnlySpan<byte> scanlineBuffer = defilteredScanline.Slice(1, defilteredScanline.Length - 1);
ReadOnlySpan<byte> trimmed = defilteredScanline.Slice(1, defilteredScanline.Length - 1);
// Convert 1, 2, and 4 bit pixel data into the 8 bit equivalent.
ReadOnlySpan<byte> scanlineSpan = this.TryScaleUpTo8BitArray(trimmed, this.bytesPerScanline, this.header.BitDepth, out IManagedByteBuffer buffer)
? buffer.GetSpan()
: trimmed;
switch (this.pngColorType)
{
@ -899,9 +906,6 @@ namespace SixLabors.ImageSharp.Formats.Png
int factor = 255 / ((int)Math.Pow(2, this.header.BitDepth) - 1);
// Convert 1, 2, and 4 bit pixel data into the 8 bit equivalent.
ReadOnlySpan<byte> scanline = ToArrayByBitsLength(scanlineBuffer, this.bytesPerScanline, this.header.BitDepth);
if (!this.hasTrans)
{
if (this.header.BitDepth == 16)
@ -909,13 +913,13 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgb48 rgb48 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 2)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.R = luminance;
rgb48.G = luminance;
rgb48.B = luminance;
color.PackFromRgb48(rgb48);
rowSpan[x] = color;
pixel.PackFromRgb48(rgb48);
rowSpan[x] = pixel;
}
}
else
@ -924,13 +928,13 @@ namespace SixLabors.ImageSharp.Formats.Png
var rgba32 = new Rgba32(0, 0, 0, byte.MaxValue);
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o++)
{
byte luminance = (byte)(scanline[o] * factor);
byte luminance = (byte)(scanlineSpan[o] * factor);
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
}
@ -941,14 +945,14 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 2)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgba64.R = luminance;
rgba64.G = luminance;
rgba64.B = luminance;
rgba64.A = luminance.Equals(this.luminance16Trans) ? ushort.MinValue : ushort.MaxValue;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -956,14 +960,14 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba32 rgba32 = default;
for (int x = pixelOffset; x < this.header.Width; x += increment)
{
byte luminance = (byte)(scanline[x] * factor);
byte luminance = (byte)(scanlineSpan[x] * factor);
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
rgba32.A = luminance.Equals(this.luminanceTrans) ? byte.MinValue : byte.MaxValue;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
}
@ -977,15 +981,15 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 4)
{
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
ushort alpha = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
ushort luminance = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
ushort alpha = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgba64.R = luminance;
rgba64.G = luminance;
rgba64.B = luminance;
rgba64.A = alpha;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -994,15 +998,15 @@ namespace SixLabors.ImageSharp.Formats.Png
for (int x = pixelOffset; x < this.header.Width; x += increment)
{
int offset = x * this.bytesPerPixel;
byte luminance = scanlineBuffer[offset];
byte alpha = scanlineBuffer[offset + this.bytesPerSample];
byte luminance = scanlineSpan[offset];
byte alpha = scanlineSpan[offset + this.bytesPerSample];
rgba32.R = luminance;
rgba32.G = luminance;
rgba32.B = luminance;
rgba32.A = alpha;
color.PackFromRgba32(rgba32);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba32);
rowSpan[x] = pixel;
}
}
@ -1010,8 +1014,7 @@ namespace SixLabors.ImageSharp.Formats.Png
case PngColorType.Palette:
ReadOnlySpan<byte> newScanline = ToArrayByBitsLength(scanlineBuffer, this.bytesPerScanline, this.header.BitDepth);
Span<Rgb24> pal = MemoryMarshal.Cast<byte, Rgb24>(this.palette);
Span<Rgb24> palettePixels = MemoryMarshal.Cast<byte, Rgb24>(this.palette);
if (this.paletteAlpha?.Length > 0)
{
@ -1020,12 +1023,12 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba32 rgba = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o++)
{
int index = newScanline[o];
int index = scanlineSpan[o];
rgba.A = this.paletteAlpha.Length > index ? this.paletteAlpha[index] : byte.MaxValue;
rgba.Rgb = pal[index];
rgba.Rgb = palettePixels[index];
color.PackFromRgba32(rgba);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba);
rowSpan[x] = pixel;
}
}
else
@ -1033,11 +1036,11 @@ namespace SixLabors.ImageSharp.Formats.Png
var rgba = new Rgba32(0, 0, 0, byte.MaxValue);
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o++)
{
int index = newScanline[o];
rgba.Rgb = pal[index];
int index = scanlineSpan[o];
rgba.Rgb = palettePixels[index];
color.PackFromRgba32(rgba);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba);
rowSpan[x] = pixel;
}
}
@ -1053,15 +1056,15 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 6)
{
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
rgba64.Rgb = rgb48;
rgba64.A = rgb48.Equals(this.rgb48Trans) ? ushort.MinValue : ushort.MaxValue;
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -1069,11 +1072,11 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgb48 rgb48 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 6)
{
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
color.PackFromRgb48(rgb48);
rowSpan[x] = color;
rgb48.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgb48.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgb48.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
pixel.PackFromRgb48(rgb48);
rowSpan[x] = pixel;
}
}
}
@ -1084,13 +1087,13 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba32 rgba = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += this.bytesPerPixel)
{
rgba.R = scanlineBuffer[o];
rgba.G = scanlineBuffer[o + this.bytesPerSample];
rgba.B = scanlineBuffer[o + (2 * this.bytesPerSample)];
rgba.R = scanlineSpan[o];
rgba.G = scanlineSpan[o + this.bytesPerSample];
rgba.B = scanlineSpan[o + (2 * this.bytesPerSample)];
rgba.A = this.rgb24Trans.Equals(rgba.Rgb) ? byte.MinValue : byte.MaxValue;
color.PackFromRgba32(rgba);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba);
rowSpan[x] = pixel;
}
}
else
@ -1098,12 +1101,12 @@ namespace SixLabors.ImageSharp.Formats.Png
var rgba = new Rgba32(0, 0, 0, byte.MaxValue);
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += this.bytesPerPixel)
{
rgba.R = scanlineBuffer[o];
rgba.G = scanlineBuffer[o + this.bytesPerSample];
rgba.B = scanlineBuffer[o + (2 * this.bytesPerSample)];
rgba.R = scanlineSpan[o];
rgba.G = scanlineSpan[o + this.bytesPerSample];
rgba.B = scanlineSpan[o + (2 * this.bytesPerSample)];
color.PackFromRgba32(rgba);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba);
rowSpan[x] = pixel;
}
}
}
@ -1117,12 +1120,12 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba64 rgba64 = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += 8)
{
rgba64.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o, 2));
rgba64.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 2, 2));
rgba64.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 4, 2));
rgba64.A = BinaryPrimitives.ReadUInt16BigEndian(scanlineBuffer.Slice(o + 6, 2));
color.PackFromRgba64(rgba64);
rowSpan[x] = color;
rgba64.R = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o, 2));
rgba64.G = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 2, 2));
rgba64.B = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 4, 2));
rgba64.A = BinaryPrimitives.ReadUInt16BigEndian(scanlineSpan.Slice(o + 6, 2));
pixel.PackFromRgba64(rgba64);
rowSpan[x] = pixel;
}
}
else
@ -1130,18 +1133,20 @@ namespace SixLabors.ImageSharp.Formats.Png
Rgba32 rgba = default;
for (int x = pixelOffset, o = 0; x < this.header.Width; x += increment, o += this.bytesPerPixel)
{
rgba.R = scanlineBuffer[o];
rgba.G = scanlineBuffer[o + this.bytesPerSample];
rgba.B = scanlineBuffer[o + (2 * this.bytesPerSample)];
rgba.A = scanlineBuffer[o + (3 * this.bytesPerSample)];
rgba.R = scanlineSpan[o];
rgba.G = scanlineSpan[o + this.bytesPerSample];
rgba.B = scanlineSpan[o + (2 * this.bytesPerSample)];
rgba.A = scanlineSpan[o + (3 * this.bytesPerSample)];
color.PackFromRgba32(rgba);
rowSpan[x] = color;
pixel.PackFromRgba32(rgba);
rowSpan[x] = pixel;
}
}
break;
}
buffer?.Dispose();
}
/// <summary>
@ -1193,13 +1198,12 @@ namespace SixLabors.ImageSharp.Formats.Png
/// Processes a scanline that uses a palette
/// </summary>
/// <typeparam name="TPixel">The type of pixel we are expanding to</typeparam>
/// <param name="defilteredScanline">The scanline</param>
/// <param name="scanline">The defiltered scanline</param>
/// <param name="row">Thecurrent output image row</param>
private void ProcessScanlineFromPalette<TPixel>(ReadOnlySpan<byte> defilteredScanline, Span<TPixel> row)
private void ProcessScanlineFromPalette<TPixel>(ReadOnlySpan<byte> scanline, Span<TPixel> row)
where TPixel : struct, IPixel<TPixel>
{
ReadOnlySpan<byte> newScanline = ToArrayByBitsLength(defilteredScanline, this.bytesPerScanline, this.header.BitDepth);
ReadOnlySpan<Rgb24> pal = MemoryMarshal.Cast<byte, Rgb24>(this.palette);
ReadOnlySpan<Rgb24> palettePixels = MemoryMarshal.Cast<byte, Rgb24>(this.palette);
var color = default(TPixel);
if (this.paletteAlpha?.Length > 0)
@ -1210,9 +1214,9 @@ namespace SixLabors.ImageSharp.Formats.Png
// channel and we should try to read it.
for (int x = 0; x < this.header.Width; x++)
{
int index = newScanline[x];
int index = scanline[x];
rgba.A = this.paletteAlpha.Length > index ? this.paletteAlpha[index] : byte.MaxValue;
rgba.Rgb = pal[index];
rgba.Rgb = palettePixels[index];
color.PackFromRgba32(rgba);
row[x] = color;
@ -1220,13 +1224,13 @@ namespace SixLabors.ImageSharp.Formats.Png
}
else
{
// TODO: We should have PackFromRgb24.
var rgba = new Rgba32(0, 0, 0, byte.MaxValue);
for (int x = 0; x < this.header.Width; x++)
{
int index = newScanline[x];
int index = scanline[x];
rgba.Rgb = pal[index];
rgba.Rgb = palettePixels[index];
color.PackFromRgba32(rgba);
row[x] = color;

5
tests/ImageSharp.Tests/Formats/Png/PngDecoderTests.cs
View File

@ -44,14 +44,14 @@ namespace SixLabors.ImageSharp.Tests
// IDAT
0x00, 0x00, 0x00, 0x0C, 0x49, 0x44, 0x41, 0x54, 0x18, 0x57, 0x63, 0x60, 0x60, 0x60, 0x00, 0x00,
0x00, 0x04, 0x00, 0x01,
// IDAT CRC
0x5C, 0xCD, 0xFF, 0x69,
// IEND
0x00, 0x00, 0x00, 0x00, 0x49, 0x45,
0x4E, 0x44,
// IEND CRC
0xAE, 0x42, 0x60, 0x82
};
@ -76,7 +76,6 @@ namespace SixLabors.ImageSharp.Tests
TestImages.Png.VimImage2,
};
public static readonly string[] TestImages48Bpp =
{
TestImages.Png.Rgb48Bpp,

Write Preview
Loading…
Cancel
Save