[FFmpeg-trac] #2686(avcodec:open): Native AAC encoder collapses at high bitrates on some samples
FFmpeg
trac at avcodec.org
Tue Oct 13 18:12:04 CEST 2015
#2686: Native AAC encoder collapses at high bitrates on some samples
-------------------------------------+-------------------------------------
Reporter: Kamedo2 | Owner:
Type: defect | klaussfreire
Priority: normal | Status: open
Version: git-master | Component: avcodec
Keywords: aac | Resolution:
regression | Blocked By:
Blocking: | Reproduced by developer: 1
Analyzed by developer: 0 |
-------------------------------------+-------------------------------------
Comment (by atomnuker):
Kamedo2: yes, all encoder options now start with "-aac_":
{{{
#!div style="font-size: 80%"
ffmpeg -help encoder=aac
{{{
AAC encoder AVOptions:
-aac_coder <int> E...A... Coding algorithm (from -1 to 3)
(default 2)
faac E...A... FAAC-inspired method
anmr E...A... ANMR method
twoloop E...A... Two loop searching method
fast E...A... Constant quantizer
-aac_ms <boolean> E...A... Force M/S stereo coding
(default false)
-aac_is <boolean> E...A... Intensity stereo coding
(default auto)
-aac_pns <boolean> E...A... Perceptual noise substitution
(default auto)
-aac_tns <boolean> E...A... Temporal noise shaping (default
auto)
-aac_pred <boolean> E...A... AAC-Main prediction (default
auto)
}}}
}}}
Any option set to automatic means that the profile will determine it by
default, unless it is set via the command line. Any option not set to a
default 'auto' means the default value indicated will be set. Also,
"-aac_ms" is not boolean as indicated but can be set to '-1' which means
it will be automatically used when there will be an encoding gain.
Keep in mind the psychoacoustic system currently doesn't account for the
cutoff which the new coder introduced, leading to bits being wasted and
the quality being decreased. Claudio will be pushing a patch to fix that.
This only affects heavy synth samples but should fix a lot of bugs which
might be related currently. This is also what's currently blocking us from
removing the 'experimental' flag.
Also, I still have to merge my LTP patches, which will happen later today.
Kamedo2: Not sure how but I got an email invitation from Shion to Slack
(Audio Video Encoding Community) which you are apparently a member of. I
understand enough Japanese to kinda understand the email and I'd love to
join but I'm still learning, let alone understanding technical jargon.
Sorry :|
Maybe after I know a little more.
--
Ticket URL: <https://trac.ffmpeg.org/ticket/2686#comment:428>
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