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November 27, 2008
audio has frames too ii
so it turns out the current release version of perian causes audio desync when playing an ffvhuff/pcm avi. moral of the story: if you're trying to resync something, for the love of god, make sure the instrument you are using to check sync is not itself causing desync. it turns out that the "skipping frame!" messages from mencoder were actually correct in that they were also skipping video frames to compensate for the mutilated ac3 input - which means that all along all i had to do was do a simple sync correction (albeit one i have to discover myself) to fix output from tiki's borked dvd recorder - assuming i first make nmf using mencoder e.g.:
mencoder -dvd-device /p/mm6 dvd://1 -fps 59.94 -vf-add tfields=0 -vf-add scale=320:240 -ofps 59.94 -ovc lavc -lavcopts vcodec=ffvhuff -oac pcm -o nmf.avi
dgindex, because it doesn't drop video frames to compensate for the bad ac3 ones, will cause randomly progressive desync. though i need to remember to use it for timing in cases when the in-game timer isn't used, such as this mm6 run (the release versions of such runs will actually be several seconds shorter than their official times indicate).
Posted by njahnke at November 27, 2008 7:44 PM
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