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fccHandler · 10th August 2005, 23:49

I know a little something about subtitles on DVD...

Like AC-3 and LPCM, they are stored in private_stream_1 and each packet payload begins with a "substream" byte immediately following its PES header. Note that an AC-3 packet includes 3 additional bytes of information (6 for LPCM), but subpictures don't. I believe the substream number ranges from 0x20 to 0x3F for subpictures. The pictures are RLE-compressed bitmaps, 2 bits per pixel.

Demuxing the stream is easy, but detecting the language would probably require you to parse the IFO. That part I know absolutely nothing about...

10th August 2005, 23:49	#45 \| Link
fccHandler Registered Jedi Join Date: Jan 2003 Location: Georgia, U.S.A. Posts: 733	I know a little something about subtitles on DVD... Like AC-3 and LPCM, they are stored in private_stream_1 and each packet payload begins with a "substream" byte immediately following its PES header. Note that an AC-3 packet includes 3 additional bytes of information (6 for LPCM), but subpictures don't. I believe the substream number ranges from 0x20 to 0x3F for subpictures. The pictures are RLE-compressed bitmaps, 2 bits per pixel. Demuxing the stream is easy, but detecting the language would probably require you to parse the IFO. That part I know absolutely nothing about... __________________ May the FOURCC be with you...