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12e856c26d
Original commit message from CVS: Riff, EBML, fourcc etc. work. Not fully finished, but better than what we used to have and definately worth a first broad testing. I've revived rifflib. Rifflib used to be a bytestream-for-riff, which just dup'ed bytestream. I've rewritten rifflib to be a modern riff- chunk parser that uses bytestream fully, plus adds some extra functions so that riff file parsing becomes extremely easy. It also contains some small usability functions for strh/strf and metadata parsing. Note that it doesn't use the new tagging yet, that's a TODO. Avidemux has been rewritten to use this. I think we all agreed that avidemux was pretty much a big mess, which is because it used all sort of bytestream magic all around the place. It was just ugly. This is a lot nicer, very complete and safe. I think this is far more robust than what the old avidemux could ever have been. Of course, it might contain bugs, please let me know. EBML writing has also been implemented. This is useful for matroska. I'm intending to modify avidemux (with a riffwriter) similarly. Maybe I'll change wavparse/-enc too to use rifflib. Lastly, several plugins have been modified to use rifflib's fourcc parsing instead of their own. this puts fourcc parsing in one central place, which should make it a lot simpler to add new fourccs. We might want to move this to its own lib instead of rifflib. Enjoy! |
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| .. | ||
| .gitignore | ||
| avi-ids.h | ||
| gstavi.c | ||
| gstavidecoder.c | ||
| gstavidemux.c | ||
| gstavidemux.h | ||
| gstavimux.c | ||
| gstavimux.h | ||
| Makefile.am | ||
| README | ||
The avi decoder plugins ----------------------- The avi decoder consists of a set of gstreamer plugins: - demuxer (avidemux) - avi to gstreamer type converter (avitypes) - windows dlls wrappers. the avidecoder element uses the above plugins to perform the avi decoding. It is constructed as a custom bin which initially only has the demuxer element in it. The demuxer has a set of padtemplates for raw audio and video. (------------------------------------) ! avidecoder ! ! (video/raw)... ! (----------) ! ! ! demuxer (video/x-msvideo, auds).. ! ! ! ! ! -src ! ! ! / ! (video/x-msvideo, vids).. - src ! ! ! ! (----------) (audio/raw)... ! ! (------------------------------------) the demuxer has a set of padtemplates for the raw avi header properties. The avi decoder will act on the new_pad signal of the demuxer element and will attach an avitype plugin to the new pad. Caps negotiation will convert the raw avi caps to the gstreamer caps. If the src pad of the avitypes plugin are compatible with the avidecoder padtemplate, the avitype pad is ghosted to the avidecoder bin, this is the case where no codec is needed (for raw PCM samples, for example). When the avitypes caps are not compatible with one of the avidecoder templates, a static autoplugger is used the find an element to connect the demuxers pad to the decoders padtemplate. When no element could be found, an windec plugin is attached to the demuxers pad and the avitypes plugin is removed from the decoder. example: -------- An avidecoder that has a video pad (decoded with windows dlls) and an audio pad (raw PCM). (----------------------------------------------------------------) ! avidecoder (--------) (------) ! ! !avitypes! !windec! /-- (video/raw) ! (----------) /-sink src--sink src ----- ! ! !demuxer (video/x-msvideo, ! ! ! ! ! ! ! auds).. (--------) (------) ! ! -sink ! (--------) ! ! / ! (video/x-..,!avitypes! ! -sink ! ! vids).. ! ! ! ! (----------) \-sink src -------------------- (audio/raw) ! (--------) ! (----------------------------------------------------------------) TODO ---- automatically generate the padtemplates from all possible avi types found in the registry.