private static void ReadBitmap24(ByteReader reader, ParseContext context, uint colorTableSize, int height, int width, IcoFrame source)
{
reader.SeekOffset += (int)colorTableSize * 4;
for (var y = height - 1; y >= 0; y--)
{
for (var x = 0; x < width; x++)
{
var b = reader.NextUint8();
var g = reader.NextUint8();
var r = reader.NextUint8();
source.CookedData[x, y] = new Rgba32(r, g, b, 255);
}
}
source.Encoding.PixelFormat = BitmapEncoding.Pixel_rgb24;
ReadBitmapMask(reader, context, height, width, source);
}
private static IcoFrame ProcessIcoFrame(ByteReader reader, ParseContext context)
{
var bWidth = reader.NextUint8();
var bHeight = reader.NextUint8();
var bColorCount = reader.NextUint8();
var bReserved = reader.NextUint8();
var wPlanes = reader.NextUint16();
var wBitCount = reader.NextUint16();
var dwBytesInRes = reader.NextUint32();
var dwImageOffset = reader.NextUint32();
if (bWidth != bHeight)
{
context.Reporter.WarnLine(IcoErrorCode.NotSquare, $"Icon is not square ({bWidth}x{bHeight}).", context.DisplayedPath, context.ImageDirectoryIndex.Value);
}
if (bReserved != FileFormatConstants._iconEntryReserved)
{
throw new InvalidIcoFileException(IcoErrorCode.InvalidFrameHeader_bReserved, $"ICONDIRECTORY.bReserved should be {FileFormatConstants._iconEntryReserved}, was {bReserved}.", context);
}
if (wPlanes > 1)
{
throw new InvalidIcoFileException(IcoErrorCode.InvalidFrameHeader_wPlanes, $"ICONDIRECTORY.wPlanes is {wPlanes}. Only single-plane bitmaps are supported.", context);
}
if (dwBytesInRes > int.MaxValue)
{
throw new InvalidIcoFileException(IcoErrorCode.InvalidFrameHeader_dwBytesInRes, $"ICONDIRECTORY.dwBytesInRes == {dwBytesInRes}, which is unreasonably large.", context);
}
if (dwImageOffset > int.MaxValue)
{
throw new InvalidIcoFileException(IcoErrorCode.InvalidFrameHeader_dwImageOffset, $"ICONDIRECTORY.dwImageOffset == {dwImageOffset}, which is unreasonably large.", context);
}
var source = new IcoFrame
{
TotalDiskUsage = dwBytesInRes + /* sizeof(ICONDIRENTRY) */ 16,
Encoding = new IcoFrameEncoding
{
ClaimedBitDepth = wBitCount,
ClaimedHeight = bHeight > 0 ? bHeight : 256u,
ClaimedWidth = bWidth > 0 ? bWidth : 256u,
},
};
source.RawData = reader.Data.Slice((int)dwImageOffset, (int)dwBytesInRes).ToArray();
var bitmapHeader = new ByteReader(source.RawData, ByteOrder.LittleEndian);
var signature = bitmapHeader.NextUint64();
bitmapHeader.SeekOffset = 0;
if (PngDecoder.IsProbablyPngFile(ByteOrderConverter.To(ByteOrder.NetworkEndian, signature)))
{
PngDecoder.DoPngEntry(bitmapHeader, context, source);
}
else
{
BmpDecoder.DoBitmapEntry(bitmapHeader, context, source);
}
return(source);
}
public static PngFileEncoding GetPngFileEncoding(Memory <byte> data)
{
var reader = new ByteReader(data, ByteOrder.NetworkEndian);
if (FileFormatConstants._pngHeader != reader.NextUint64())
{
throw new InvalidPngFileException(IcoErrorCode.NotPng, $"Data stream does not begin with the PNG magic constant");
}
var chunkLength = reader.NextUint32();
var chunkType = reader.NextUint32();
if (chunkType != _ihdrChunkName)
{
throw new InvalidPngFileException(IcoErrorCode.PngBadIHDR, $"PNG file should begin with IHDR chunk; found {chunkType} instead");
}
if (chunkLength < 13)
{
throw new InvalidPngFileException(IcoErrorCode.PngBadIHDR, $"IHDR chunk is invalid length {chunkLength}; expected at least 13 bytes");
}
var result = new PngFileEncoding
{
Width = reader.NextUint32(),
Height = reader.NextUint32(),
BitsPerChannel = reader.NextUint8(),
ColorType = (PngColorType)reader.NextUint8(),
};
if (result.Width == 0 || result.Height == 0)
{
throw new InvalidPngFileException(IcoErrorCode.PngIllegalInputDimensions, $"Illegal Width x Height of {result.Width} x {result.Height}");
}
switch (result.BitsPerChannel)
{
case 1:
case 2:
case 4:
case 8:
case 16:
break;
default:
throw new InvalidPngFileException(IcoErrorCode.PngIllegalInputDepth, $"Illegal bits per color channel / palette entry of {result.BitsPerChannel}");
}
switch (result.ColorType)
{
case PngColorType.Grayscale:
case PngColorType.RGB:
case PngColorType.Palette:
case PngColorType.GrayscaleAlpha:
case PngColorType.RGBA:
break;
default:
throw new InvalidPngFileException(IcoErrorCode.PngIllegalColorType, $"Illegal color type {result.ColorType}");
}
return(result);
}