[Ffmpeg-devel-irc] ffmpeg.log.20130420

[burek]

[01:13] <msmithng> can anyone explain this to me?
[01:13] <msmithng> GPAC ISO Hint Handler
[01:13] <msmithng> sorry
[01:13] <msmithng>     Stream #0:2(und): Data: none (rtp  / 0x20707472), 66 kb/s
[01:13] <msmithng>     Metadata:
[01:13] <msmithng>       creation_time   : 2013-04-13 21:27:28
[01:13] <msmithng>       handler_name    : GPAC ISO Hint Handler
[01:14] <larrikin> gpac.sourceforge.net ?
[01:16] <msmithng> ok, I'll start there&
[01:23] <msmithng> seeing these in ffprobe output as
[01:23] <msmithng> Unsupported codec with id 0 for input stream 2
[01:23] <msmithng> Unsupported codec with id 0 for input stream 3
[01:25] <StFS> Hi. I'm having audio sync problems when I record my desktop. The audio is always "downpitched" and lags. I've tried -async 1 and that fixes the sync but introduces very annoying "clipping"
[01:29] <StFS> here is the command I'm using: http://pastebin.com/ZSZDa3Ef
[01:38] <durandal_1707> StFS: perhaps your machine is not fast enough to encode it in realtime...
[01:39] <larrikin> msmithng: http://records.sigmm.ndlab.net/2012/12/open-source-column-gpac/
[01:42] <larrikin> msmithng: seems like you might need something called MP4Box to decode your stream
[02:13] <msmithng> larrikin: thank you sir& I'll look into that for sure
[03:33] <Max-P> Hi, does by chance anyone here knows how to force 2 live inputs (x11grab+alsa) keep in sync. Or is there a way to adjust buffers so it holds the same amount of data? Searching for a week now, still haven't found anything relevant :/ Thanks!
[04:31] <leo2013> hello?
[04:34] <Max-P> leo2013: There are people here. We just don't respond under 3 minutes... Meh.
[04:52] <THoRIX_> hi, i've been working with dranger's ffmpeg tutorials (im building under win64 using zeranoe builds) and im noticing something strange. Depending on how many logical cores are detected the video sync timings seem to vary.  For example if i set the program affinity to a single core then the video frames match perfectly with the audio, the more cores i enable the more the video is off sync (always behind the audio).  I can replicate the behaviour by programmical
[04:52] <THoRIX_> ly setting the thread_count under AVCodecContext.  Can anyone shed any light on why this is happening?
[12:26] <hendry> what's the best audio codec for playback on the Web? Just voice? webm? And how do I target that?
[12:27] <elkng> can ffmpeg generate some waves that makes brain relaxed ?
[12:27] <ubitux> yes
[12:28] <hendry> wondering if speex was still a thing
[12:28] <elkng> hendry: speex ?
[12:28] <hendry> audio codec IIRC
[12:28] <elkng> ubitux: how ?
[12:28] <ubitux> elkng: https://ffmpeg.org/ffmpeg-formats.html#sbg
[12:29] <klaxa> yes, audio codec targeted at voice compression
[12:29] <klaxa> for voip and such
[12:31] <elkng> ubitux: what that link about, how to generate sound waves with ffmpeg ? I need some specific audio waves for brain
[12:32] <saste> elkng, audio waves for brain, why? Now I'm curious
[12:32] <saste> but yes sbg looks interesting from that point of view
[12:32] <ubitux> elkng: "SBaGen -- Binaural Beat Brain Wave Experimenter's Lab"
[16:56] <xlinkz0> is it possible to get information about frames(pts, dts, is keyframe, frame type) from an encoded files without actually decoding the frames?
[16:58] <xlinkz0> even if ffmpeg doesn't have that functionality.. is it theoretically possible?
[16:59] <JEEB> in sane containers pts/dts and frame type might be get'able
[16:59] <xlinkz0> any functions in ffmpeg that can do that?
[17:00] <xlinkz0> i don't need it to work in general
[17:23] <zap0> anyone know of a way to determine the number of cuts in a movie?
[17:24] <xlinkz0> pkt_pts is in AV_TIME_BASE units right?
[17:25] <xlinkz0> i don't get it, the difference between every frame pts is on average 3600 and the stream is 25fps
[17:26] <xlinkz0> 25*3600 = 90k
[17:26] <xlinkz0> shouldn't it be 100k so that it makes a second?
[19:29] <xlinkz0> is there some way to iterate through keyframes and getting basic info about them like pts and dts?
[20:18] <esing> Hey
[20:18] <esing> Is avconv also supported in #ffmpeg?
[20:19] <klaxa> no
[20:19] <klaxa> #libav is the channel you are seeking
[20:19] <esing> Thanks
[20:20] <esing> (I try to record from /dev/video0 and when I tried it with ffmpeg I got the message: This program is only provided for compatibility and will be removed in a future release. Please use avconv instead.
[20:20] <durandal_1707> because you are using ffmpeg from older Libav release
[20:21] <klaxa> you can get a recent static ffmpeg build or compile the latest version from source
[20:23] <esing> Oh, I see
[20:23] <iive> the message is a lie
[20:23] <iive> libav doesn't support ffmpeg
[20:24] <iive> ffmpeg supports ffmpeg.
[20:24] <esing> I use the kubuntu package and I worry if I compile the newest ffmpeg source myself that it doesn't updates automatically anymore
[20:25] <esing> Shall I ignore the message and work with the "older" ffmpeg?
[20:27] <klaxa> right now you're not using ffmpeg
[20:34] <iive> there should be debian package on the ffmpeg download page
[20:40] <esing> klaxa, Hm? If I write ffmpeg in the terminal I suppose Iam using ffmpeg
[20:43] <xlinkz0> esing: http://blog.pkh.me/p/13-the-ffmpeg-libav-situation.html
[20:44] <xlinkz0> apparently ubuntu is lying to you
[20:44] <esing> xlinkz0, thanks for the link
[20:45] <xlinkz0> good thing i compiled from source, didn't even know about this until now :\
[20:51] <xlinkz0> if codec_context->time_base is 1/180000 and fps is 25 shouldn't the pts difference between frame i+25 and i be 180000?
[20:55] <xlinkz0> is this a weekend thing or is the channel usually so quiet?
[20:57] <zap0> everyones baked
[22:31] <Fjorgynn> :D
[22:36] <xlinkz0> why isn't ticks_per_frame built into time_base?
[22:36] <xlinkz0> i mean what's the purpose of having two variables
[22:37] <xlinkz0> is it for legacy compatibility or another reason?
[22:43] <Fjorgynn> :D
[22:43] <Fjorgynn> Dunno
[22:43] <Fjorgynn> sorry
[22:51] <brontosaurusrex> is -aspect 16:9 still valid option?
[22:53] <xlinkz0> channel is dead come back monday
[22:56] <Fjorgynn> :)
[22:56] <Fjorgynn> brontosaurusrex: -vf aspect=16:9
[22:56] <Fjorgynn> I think
[22:57] <xlinkz0> brontosaurusrex: ffmpeg -h | grep aspect
[22:59] <brontosaurusrex> right, its still valid
[23:00] <brontosaurusrex> probably due to a fact that audio files can't really have aspect :P
[23:09] <brontosaurusrex> burek, do you have any cool notes on how to built completely static ffmpeg on debian?
[23:10] <brontosaurusrex> i need x11_grab and fdk_aac
[23:11] <esing> I worry if I compile ffmpeg that I have compatibilty issues with libav's libaries
[23:12] <esing> Or maybe I read it wrong: "However, both Libav and FFmpeg periodically break backward compatibility in order to more easily provide new features, so applications built against one version will not always work with the next. "
[23:12] <esing> (From: https://launchpad.net/~jon-severinsson/+archive/ffmpeg )
[23:14] <galtgendo> is there a way to reindex an avi file using ffmpeg alone ?
[23:15] <galtgendo> also, is reindexing possible without reencoding ?
[23:18] <brontosaurusrex> -c:v copy -c:a copy < galtgendo
[23:20] <galtgendo> brontosaurusrex: that doesn't work - the video seems OK, but the audio is shot
[23:21] <brontosaurusrex> shot?
[23:31] <galtgendo> it's ...I don't know...garbled ?
[23:55] <xlinkz0> esing: just remove all of libav and compile ffmpeg
[23:56] <esing> xlinkz0, and if I'd wanted to use libav again I would do the same reverse, but install the libav ubuntu package, right?
[23:57] <xlinkz0> idk, they conflict so choose one or the other
[23:57] <xlinkz0> or install ffmpeg into a non shared folder
[23:58] <esing> thanks for the tip
[23:58] <xlinkz0> better yet do that, compile ffmpeg without installing
[23:58] <xlinkz0> and alias to its location
[00:00] --- Sun Apr 21 2013