> > (3) Tuned to HDTV channel. No go. AC3 has the same startcode as MPEG2, > > thus myth(or ffmpeg?) gives it the codec_id = CODEC_ID_MPEG2. Hence all > > along Myth is trying to use the MPEG2 decoder to decode AC3 streams > > (that's why I am hearing rubbish when I use a AC3 APID). > > Depends. AC3 should be in privete_stream_1 PES packets in TS stream. > At least in DVB and American ATSC. This is where ffmpeg searches for > it, see mpegps_read_packet and mpegps_read_pes_header. What do you > mean with "startcode"?
I'll have to correct myself right away. At least in ATSC content AC3 frame begins just after PES headers, in DVD there seems to be a four byte header in front of the AC3 frame. Ffmpeg seems to be expecting this header and not AC3 frame straight away so it does not recognise these. I don't have any dvd documentation so I cannot confirm this. Just some conversations on the 'net. :) I do not have any DVB AC3 content, if you have any I could check it out and make a patch for ffmpeg. AC3 frame begins with (0x0b 0x77) so we I'd guess we have to modify mpegps_read_packet and mpegps_read_pes_header to take this into account. - Juha -- Madness takes it's toll. Please have exact change.
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