internal void Read(GifReader reader)
{
Byte size = reader.ReadByte();
if (size != 4)
{
System.Diagnostics.Debug.WriteLine("Wrong size of " + ToString());
}
Byte flags = reader.ReadByte();
disposalMethod = (GifDisposalMethod)((flags & 0x1C) >> 2);
userInputExpected = 0x02 == (flags & 0x02);
transparency = 0x01 == (flags & 0x01);
delay = reader.ReadUInt16();
transparencyIndex = reader.ReadByte();
Byte terminator = reader.ReadByte();
if (terminator != 0x00)
{
throw new Exception("Unknown extension terminator: 0x" + terminator.ToString("X2"));
}
}
internal void Read(GifReader reader)
{
width = reader.ReadUInt16();
height = reader.ReadUInt16();
Byte flags = reader.ReadByte();
globalColorTableFlag = 0x80 == (flags & 0x80);
colorResolution = (Byte)(((flags & 0x70) >> 4) + 1);
globalColorTableSorted = 0x08 == (flags & 0x08);
globalColorTableSize = (UInt16)(2 << (flags & 0x07));
backgroundColorIndex = reader.ReadByte();
pixelAspectRatio = reader.ReadByte();
}
internal void Read(GifReader reader)
{
Byte size = reader.ReadByte();
if (size != 12)
{
System.Diagnostics.Debug.WriteLine("Wrong size of " + ToString());
}
left = reader.ReadUInt16();
top = reader.ReadUInt16();
width = reader.ReadUInt16();
height = reader.ReadUInt16();
cellWidth = reader.ReadByte();
cellHeight = reader.ReadByte();
foregroundColor = reader.ReadByte();
backgroundColor = reader.ReadByte();
text = reader.ReadTextSubBlocks();
}
internal void Read(GifReader reader)
{
Byte size = reader.ReadByte();
if (size != 11)
{
System.Diagnostics.Debug.WriteLine("Wrong size of " + ToString());
}
applicationIdentifier = reader.ReadString(8);
applicationAuthenticationCode = reader.ReadString(3);
bytes = reader.ReadBinarySubBlocks();
}
internal void Read(GifReader reader)
{
left = reader.ReadUInt16();
top = reader.ReadUInt16();
width = reader.ReadUInt16();
height = reader.ReadUInt16();
Byte flags = reader.ReadByte();
localColorTableFlag = 0x80 == (flags & 0x80);
interlaced = 0x40 == (flags & 0x40);
localColorTableSorted = 0x20 == (flags & 0x20);
localColorTableSize = (UInt16)(2 << (flags & 0x07));
}
internal void Read(GifReader reader)
{
lzwMinimumCodeSize = reader.ReadByte();
imageData = reader.ReadBinarySubBlocks();
}
public void Read(Stream stream)
{
blocks.Clear();
// reader
GifReader reader = new GifReader(stream);
// Header
AddBlock(new GifHeaderBlock(reader));
// Logical Screen Descriptor
GifLogicalScreenDescriptorBlock gifLogicalScreenDescriptorBlock = new GifLogicalScreenDescriptorBlock(reader);
AddBlock(gifLogicalScreenDescriptorBlock);
// Global Color Table
if (gifLogicalScreenDescriptorBlock.GlobalColorTableFlag)
{
AddBlock(new GifGlobalColorTableBlock(reader, gifLogicalScreenDescriptorBlock));
}
// Segments
while (true)
{
Byte identifier = reader.ReadByte();
switch (identifier)
{
// Frames
case 0x2C:
GifImageDescriptorBlock gifImageDescriptorBlock = new GifImageDescriptorBlock(reader);
AddBlock(gifImageDescriptorBlock);
if (gifImageDescriptorBlock.LocalColorTableFlag)
{
AddBlock(new GifLocalColorTableBlock(reader, gifImageDescriptorBlock));
}
AddBlock(new GifTableBasedImageDataBlock(reader));
break;
// Extensions
case 0x21:
Byte label = reader.ReadByte();
switch (label)
{
case 0xF9:
AddBlock(new GifGraphicControExtensionBlock(reader));
break;
case 0xFE:
AddBlock(new GifCommentExtensionBlock(reader));
break;
case 0x01:
AddBlock(new GifPlainTextExtensionBlock(reader));
break;
case 0xFF:
AddBlock(GifApplicationExtensionBlock.Create(reader));
break;
default:
AddBlock(new GifExtensionBlock(label, reader));
break;
}
break;
// Trailer
case 0x3B:
AddBlock(new GifTrailerBlock());
return;
default:
throw new Exception("Unknown segment identifier: 0x" + identifier.ToString("X2"));
}
}
}