public override IImageDecoder OpenImage(ArcFile arc, Entry entry)
{
byte pic_method = arc.File.View.ReadByte(entry.Offset);
if (pic_method != 1 && pic_method != 2)
{
return(base.OpenImage(arc, entry));
}
var pent = (PdImageEntry)entry;
byte[] baseline = null;
var dir = arc.Dir as List <Entry>;
for (int i = pent.Number - 1; i >= 0; --i)
{
var base_entry = dir[i];
byte base_method = arc.File.View.ReadByte(base_entry.Offset);
if (base_method != 1 && base_method != 2)
{
PicMetaData base_info;
using (var base_input = arc.File.CreateStream(base_entry.Offset, base_entry.Size))
{
base_info = s_picFormat.Value.ReadMetaData(base_input) as PicMetaData;
if (null == base_info)
{
throw new InvalidFormatException();
}
using (var reader = new PicFormat.Reader(base_input, base_info))
{
reader.Unpack();
baseline = reader.Data;
}
}
var overlay_info = new PdOverlayMetaData {
Width = base_info.Width,
Height = base_info.Height,
BPP = 24,
Method = pic_method,
ChunkCount = arc.File.View.ReadInt32(pent.Offset + 4),
};
var input = arc.File.CreateStream(pent.Offset, pent.Size);
return(new PdOverlayImage(input, overlay_info, baseline));
}
}
return(base.OpenImage(arc, entry)); // essentialy InvalidFormatException
}
public PdOverlayImage(IBinaryStream input, PdOverlayMetaData info, byte[] baseline) : base(input, info)
{
m_method = info.Method;
m_chunk_count = info.ChunkCount;
m_baseline = baseline;
}
