I've run into some issues with the lossless mpeg2 commercial cutting not occurring at the same frame specified by myth. I'm still trying to track it down, but my guess is that it is related to some difference in how the 2 tools count frames, but I am still debugging.
Anyhow, one possibility to solve the issue was to load the key frame index from mythtv, and ensure that at the same packet position, the frame numbers were the same. But there are 2 issues with this: 1) Apparently myth stores the previous key frame number with the current file position when writing MARK_GOP_BYFRAME. This makes sense, as you may need the previous Sequence to calculate the 1st frames in the current sequence if they are 'B' frames 2) Myth is still using MARK_GOP_START which assumes a fixed key distribution. This would be ok if the key frame dist was stored somewhere (which doesn't seem to be), and if myth had a way to ensure the keyframedist was really a constant (which it doesn't actually do). This means that a DVB stream which can have a variable sequence length could get marked as using a fixed key-frame distance if it happens that the first sequence has 12 or 15 frames (I think). So my question is really about (2). Why do we still use this method at all? Can't we get rid of it, and just MARK_GOP_BYFRAME for all mpeg2 files, and just force a rebuild of the markup-table when a stream which used it is read? Or is there some benefit to using MARK_GOP_START? .Geoff .Geoff _______________________________________________ mythtv-dev mailing list [email protected] http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-dev
