SV7 to SV 8 conversion for matroska integration : call for opinions
Christian HJ Wiesner <[email protected]> Sun, 16 Nov 2003 23:30:18 +0100
| Newsgroups | gmane.comp.multimedia.matroska.devel,gmane.comp.audio.mpc.devel,gmane.comp.audio.mpc.general |
|---|---|
| Message-ID | <[email protected]> |
Hi, please use the 'reply all' button of your mail client when replying, so all lists get copied. Frank convinced us that using SV7 in matroska is maybe not a good idea. Therefore the matroska team was discussing a couple of options today about MPC integration into matroska : 1. Wait for Frank to write a SV7 to SV8 'repacker' tool. This would slightly increa'se overhead, but this way old existing SV7 files could be packed into matroska, and all existing encoders could be used for movie soundtrack encoding 2. Make an encoder filter for DirectShow or a little CLI app with libmatroska based on Frank's 'alpha' SV8 encoder, which seems to be quite usable and according to Frank was tuned to overcome some reported sound limitations in the existing SV7 encoder. We could tag the current, 'alpha SV8 bitstream' as SV 7.2 , SV 7.5 or even SV8, and write the blocks directly into matroska files, stripping even the block size from the SV8 alpha bitstream to become as independant as possible from future bitstream changes. The chances are good that these files would be 100% SV8 compatible. If not, we could tag them differently, or convince Frank to make SV9 instead of SV8 ;-) .... 3. matroska has a very powerful and complex lacing and frame handling system, allowing us to even mux SV7 streams into matroska files, without breaking the specs. For this case we could put 32 MPC frames into a single matroska block and use either the enhanced EBML lacing or the so-called time-slices, allowing us to group a complete 'self-decodable' group of blocks into one matroska block. That way we even dont care if single bits of one frame are attached to other frames, as they form an entity in the matroska file. I would like to hear your opinions on that. Everybody is clearly invited to tell us his personal opinion about this, even if its not technically founded. Best regards Christian