GNOME Bugzilla – Bug 656734
[aacparse] Assumes 1024 samples per frame
Last modified: 2011-09-07 09:23:40 UTC
aacparse currently assumes 1024 samples per frame. Depending on the profile this can be wrong. AFAIK there can be 1024 or 960 samples with LC, 2048 samples with HE-AAC and 480 or 512 LD. No idea about the other profiles.
Created attachment 195785 [details] [review] aacparse: parse codec_data to determine samples per frame There is some info in standard codec_data that allows for 960 or 1024 samples, and attached patch parses and then uses that bit of info. However, AFAIK, in case of SBR (HE-AAC), there can be 2048 decoded samples, but those are 1024 samples upsampled along with a doubled sample rate, so that comes down to the same frame duration (which is all aacparse is doing here). Don't know about the other cases though (specs or any way to bitpick those).
Looks good and you're right with HE-AAC. No idea about the LD (low delay) profile though, the only information I found about it was in the OpenMAX specification but I didn't search very hard and we don't support it yet anyway :)
commit 625e7a6143a0eefa2cf79550b6e66c44e4c19bf0 Author: Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk> Date: Tue Sep 6 15:59:49 2011 +0200 aacparse: parse codec_data to determine number of samples per frame Fixes #656734.