public static void EmitIco(string outputPath, ParseContext context)
{
var writer = new ByteWriter(ByteOrder.LittleEndian);
writer.AddUint16(FileFormatConstants._iconMagicHeader);
writer.AddUint16(FileFormatConstants._iconMagicType);
writer.AddUint16((ushort)context.GeneratedFrames.Count);
var offsets = new Queue <uint>();
foreach (var frame in context.GeneratedFrames)
{
var width = frame.Encoding.ClaimedWidth;
var height = frame.Encoding.ClaimedHeight;
var bitDepth = frame.Encoding.ClaimedBitDepth;
writer.AddUint8((byte)(width >= 256 ? 0 : width)); // bWidth
writer.AddUint8((byte)(height >= 256 ? 0 : height)); // bHeight
writer.AddUint8((byte)(bitDepth < 8 ? 1u << (int)bitDepth : 0)); // bColorCount
writer.AddUint8(0); // bReserved
writer.AddUint16(1); // wPlanes
writer.AddUint16((ushort)bitDepth); // wBitCount
writer.AddUint32((uint)frame.RawData.Length); // dwBytesInRes
offsets.Enqueue((uint)writer.SeekOffset);
writer.AddUint32(0); // dwImageOffset (will fix later)
}
foreach (var frame in context.GeneratedFrames)
{
var currentOffset = writer.SeekOffset;
writer.SeekOffset = (int)offsets.Dequeue();
writer.AddUint32((uint)currentOffset); // dwImageOffset
writer.SeekOffset = currentOffset;
writer.AddBlob(frame.RawData);
frame.TotalDiskUsage = (uint)frame.RawData.Length + /* sizeof(ICONDIRENTRY) */ 16;
}
File.WriteAllBytes(outputPath, writer.Data.ToArray());
}
private static void EncodeBitmapHeader(IcoFrame source, Dialect dialect, BitmapEncoding encoding, Rgba32[] colorTable, ByteWriter writer, out uint offsetToImageSize)
{
if (dialect != Dialect.Ico)
{
writer.AddUint16(FileFormatConstants._bitmapFileMagic);
writer.AddUint32(0); // Size will be filled in later
writer.AddUint32(0); // Reserved
writer.AddUint32(0); // Offset will be filled in later
}
writer.AddUint32(FileFormatConstants._bitmapInfoHeaderSize);
writer.AddUint32((uint)source.CookedData.Width);
writer.AddUint32((uint)source.CookedData.Height * ((dialect == Dialect.Ico) ? 2u : 1u));
writer.AddUint16(1); // biPlanes
writer.AddUint16((ushort)BmpUtil.GetBitDepthForPixelFormat(encoding)); // biBitCount
writer.AddUint32(FileFormatConstants.BI_RGB); // biCompression
offsetToImageSize = (uint)writer.SeekOffset;
writer.AddUint32(0); // biSizeImage
writer.AddUint32((dialect == Dialect.Ico) ? 0u : FileFormatConstants._72dpiInPixelsPerMeter); // biXPelsPerMeter
writer.AddUint32((dialect == Dialect.Ico) ? 0u : FileFormatConstants._72dpiInPixelsPerMeter); // biYPelsPerMeter
writer.AddUint32((uint)(colorTable?.Length ?? 0)); // biClrUsed
writer.AddUint32(0); // biClrImportant
if (colorTable != null)
{
foreach (var color in colorTable)
{
writer.AddUint8(color.B);
writer.AddUint8(color.G);
writer.AddUint8(color.R);
writer.AddUint8(0);
}
}
if (dialect != Dialect.Ico)
{
while (writer.Data.Count % 4 != 0)
{
writer.AddUint8(0);
}
}
}
private static byte[] FinalizeBitmap(IcoFrame source, BitmapEncoding encoding, Dialect dialect, ByteWriter writer, uint offsetToData, uint offsetToImageSize)
{
var offsetToEndOfData = writer.SeekOffset;
if (dialect == Dialect.Ico)
{
var padding = writer.Data.Count % 4;
var inferMaskFromAlpha = (source.Encoding.PixelFormat == BitmapEncoding.Pixel_argb32 && encoding != BitmapEncoding.Pixel_argb32);
for (var y = source.CookedData.Height - 1; y >= 0; y--)
{
var bits = new BitWriter(writer);
for (var x = 0; x < source.CookedData.Width; x++)
{
var mask = inferMaskFromAlpha
? (source.CookedData[x, y].A == 0)
: source.Mask[x, y];
bits.AddBit1((byte)(mask ? 1 : 0));
}
while ((writer.Data.Count % 4) != padding)
{
writer.AddUint8(0);
}
}
}
if (dialect != Dialect.Ico)
{
writer.SeekOffset = 2;
writer.AddUint32((uint)writer.Data.Count);
writer.SeekOffset = 10;
writer.AddUint32(offsetToData);
}
writer.SeekOffset = (int)offsetToImageSize;
writer.AddUint32((uint)(offsetToEndOfData - offsetToData)); // biSizeImage
return(writer.Data.ToArray());
}
private static byte[] EncodeRgbBitmap(IcoFrame source, ParseContext context, BitmapEncoding encoding, Dialect dialect)
{
var writer = new ByteWriter(ByteOrder.LittleEndian);
EncodeBitmapHeader(source, dialect, encoding, null, writer, out var offsetToImageSize);
var offsetToData = (uint)writer.Data.Count;
var padding = writer.Data.Count % 4;
for (var y = source.CookedData.Height - 1; y >= 0; y--)
{
var bits = new BitWriter(writer);
for (var x = 0; x < source.CookedData.Width; x++)
{
var color = source.CookedData[x, y];
if (source.Mask[x, y])
{
switch (context.MaskedImagePixelEmitOptions)
{
case StrictnessPolicy.Compliant:
case StrictnessPolicy.Loose:
color = new Rgba32(0, 0, 0, 0);
break;
case StrictnessPolicy.PreserveSource:
// Pass through whatever the original pixel was.
break;
}
}
switch (encoding)
{
case BitmapEncoding.Pixel_rgb15:
var value = X8To5(color.R) << 10 | X8To5(color.G) << 5 | X8To5(color.B);
writer.AddUint16((ushort)value);
break;
case BitmapEncoding.Pixel_rgb24:
writer.AddUint8(color.B);
writer.AddUint8(color.G);
writer.AddUint8(color.R);
break;
case BitmapEncoding.Pixel_0rgb32:
writer.AddUint8(color.B);
writer.AddUint8(color.G);
writer.AddUint8(color.R);
writer.AddUint8(0);
break;
case BitmapEncoding.Pixel_argb32:
writer.AddUint8(color.B);
writer.AddUint8(color.G);
writer.AddUint8(color.R);
writer.AddUint8(color.A);
break;
}
}
while ((writer.Data.Count % 4) != padding)
{
writer.AddUint8(0);
}
}
return(FinalizeBitmap(source, encoding, dialect, writer, offsetToData, offsetToImageSize));
}
private static byte[] EncodeIndexedBitmap(ParseContext context, BitmapEncoding encoding, Dialect dialect, IcoFrame source)
{
var numBits = BmpUtil.GetBitDepthForPixelFormat(encoding);
var colorTable = BuildColorTable(1u << numBits, context, source);
if (colorTable == null)
{
context.LastEncodeError = IcoErrorCode.TooManyColorsForBitDepth;
return(null);
}
var writer = new ByteWriter(ByteOrder.LittleEndian);
EncodeBitmapHeader(source, dialect, encoding, colorTable, writer, out var offsetToImageSize);
var reverseTable = new Dictionary <Rgba32, int>();
for (var i = 0; i < colorTable.Length; i++)
{
if (!reverseTable.ContainsKey(colorTable[i]))
{
reverseTable.Add(colorTable[i], i);
}
}
var offsetToData = (uint)writer.Data.Count;
var padding = writer.Data.Count % 4;
for (var y = source.CookedData.Height - 1; y >= 0; y--)
{
var bits = new BitWriter(writer);
for (var x = 0; x < source.CookedData.Width; x++)
{
var color = source.CookedData[x, y];
if (source.Mask[x, y])
{
switch (context.MaskedImagePixelEmitOptions)
{
case StrictnessPolicy.Compliant:
color = new Rgba32(0, 0, 0, 255);
break;
case StrictnessPolicy.PreserveSource:
// Pass through whatever the original pixel was.
break;
case StrictnessPolicy.Loose:
color = colorTable.First();
break;
}
}
color.A = 255;
var index = reverseTable[color];
bits.AddBits((uint)numBits, (byte)index);
}
while ((writer.Data.Count % 4) != padding)
{
writer.AddUint8(0);
}
}
return(FinalizeBitmap(source, encoding, dialect, writer, offsetToData, offsetToImageSize));
}
