public override ImageMetaData ReadMetaData(Stream stream)
{
if (0xff != stream.ReadByte() || 0xd8 != stream.ReadByte())
{
return(null);
}
using (var file = new ArcView.Reader(stream))
{
while (-1 != file.PeekChar())
{
ushort marker = Binary.BigEndian(file.ReadUInt16());
if ((marker & 0xff00) != 0xff00)
{
break;
}
int length = Binary.BigEndian(file.ReadUInt16());
if ((marker & 0x00f0) == 0xc0 && marker != 0xffc4)
{
if (length < 8)
{
break;
}
int bits = file.ReadByte();
uint height = Binary.BigEndian(file.ReadUInt16());
uint width = Binary.BigEndian(file.ReadUInt16());
int components = file.ReadByte();
return(new ImageMetaData {
Width = width,
Height = height,
BPP = bits * components,
});
}
file.BaseStream.Seek(length - 2, SeekOrigin.Current);
}
return(null);
}
}
public override ImageMetaData ReadMetaData(Stream stream)
{
if (0xff != stream.ReadByte() || 0xd8 != stream.ReadByte())
return null;
using (var file = new ArcView.Reader (stream))
{
while (-1 != file.PeekChar())
{
ushort marker = Binary.BigEndian (file.ReadUInt16());
if ((marker & 0xff00) != 0xff00)
break;
int length = Binary.BigEndian (file.ReadUInt16());
if ((marker & 0x00f0) == 0xc0 && marker != 0xffc4)
{
if (length < 8)
break;
int bits = file.ReadByte();
uint height = Binary.BigEndian (file.ReadUInt16());
uint width = Binary.BigEndian (file.ReadUInt16());
int components = file.ReadByte();
return new ImageMetaData {
Width = width,
Height = height,
BPP = bits * components,
};
}
file.BaseStream.Seek (length-2, SeekOrigin.Current);
}
return null;
}
}
public override ImageMetaData ReadMetaData(Stream stream)
{
using (var file = new ArcView.Reader(stream))
{
short id_length = file.ReadByte();
short colormap_type = file.ReadByte();
if (colormap_type > 1)
{
return(null);
}
short image_type = file.ReadByte();
ushort colormap_first = file.ReadUInt16();
ushort colormap_length = file.ReadUInt16();
short colormap_depth = file.ReadByte();
int pos_x = file.ReadInt16();
int pos_y = file.ReadInt16();
uint width = file.ReadUInt16();
uint height = file.ReadUInt16();
int bpp = file.ReadByte();
if (bpp != 32 && bpp != 24 && bpp != 16 && bpp != 15 && bpp != 8)
{
return(null);
}
short descriptor = file.ReadByte();
uint colormap_offset = (uint)(18 + id_length);
switch (image_type)
{
default: return(null);
case 1: // Uncompressed, color-mapped images.
case 9: // Runlength encoded color-mapped images.
case 32: // Compressed color-mapped data, using Huffman, Delta, and
// runlength encoding.
case 33: // Compressed color-mapped data, using Huffman, Delta, and
// runlength encoding. 4-pass quadtree-type process.
if (colormap_depth != 24 && colormap_depth != 32)
{
return(null);
}
break;
case 2: // Uncompressed, RGB images.
case 3: // Uncompressed, black and white images.
case 10: // Runlength encoded RGB images.
case 11: // Compressed, black and white images.
break;
}
return(new TgaMetaData {
OffsetX = pos_x,
OffsetY = pos_y,
Width = width,
Height = height,
BPP = bpp,
ImageType = image_type,
ColormapType = colormap_type,
ColormapOffset = colormap_offset,
ColormapFirst = colormap_first,
ColormapLength = colormap_length,
ColormapDepth = colormap_depth,
Descriptor = descriptor,
});
}
}