[Ffmpeg-devel-irc] ffmpeg.log.20121209

[burek]

[00:16] <smj> -sws_flags apparently has options for MMX and MMX2 acceleration... Are those auto-detected and no one should bother to set them manually?
[00:17] <JEEB> they're autodetected
[00:17] <JEEB> as far as I know
[00:17] <smj> okay, thanks
[00:17] <JEEB> because I was making tests and ended up basing the results of the optimized code path >_>
[00:17] <JEEB> (queue tests failing on everything else)
[00:18] <JEEB> (they're not bit-exact)
[00:19] <smj> what's the default resizing algorithm? or downscaling algorithm
[00:56] <smj> how do I list x264 presets?
[00:59] <JEEB> x264 --help, but in case you don't have the x264 binary installed you could just see http://mewiki.project357.com/wiki/X264_Settings#preset
[00:59] <JEEB> :)
[01:56] <wannabegeekster> I am on Linux and I want to record audio from my speaker output.  How can I figure out the right device to tell ffmpeg when recording?
[02:06] <smj> wannabegeekster: are you using PulseAudio
[02:06] <smj> ?
[02:54] <eekthecat> Hello.
[02:55] <sacarasc> OMG! I remember Eek. :D
[02:56] <eekthecat> Heh. It never hurts to help.
[02:56] <eekthecat> I watched way too much of that show.
[03:00] <eekthecat> I wondered if anyone would have an opinion about an error I get on some files when trying to go .flac to ALAC, sometimes I get a error about frame rate very high for a muxer not efficiently supporting it.
[03:06] <eekthecat> What did you like best about eek?
[03:31] <jedypod> Greetings! I am trying to compile ffmpeg on Mac OSX 10.8.2, following the guide here: https://ffmpeg.org/trac/ffmpeg/wiki/MacOSXCompilationGuide
[03:31] <jedypod> All of the dependencies installed without a problem following the instructions. When I try to compile and install ffmpeg, I run into an issue. I get the error "ERROR: libopenjpeg not found". It seems that the compiler is not finding the openjpeg library. I found this post about this issue https://github.com/mxcl/homebrew/issues/15772, and there is some mention of openjpeg installing its headers into a non-standard directory. Is there any
[03:31] <jedypod> way to manually specify the location of the headers for openjpeg in the ./configure command? Thanks for anyone who can help!
[03:35] <wannabegeekster> smj: Using Alsa as far as I know.  Should I be using Pulse Audio?
[03:35] <smj> no
[04:39] <elkng> is it possible to make vide with 25 frame that is invisible in regular way ?
[04:40] <elkng> s/vide/video
[04:40] <smj> invisible?
[04:51] <elkng> smj: have ever heard of 25th Frame Effect ? is ffmpeg can do same videos ?
[04:53] <smj> I don't know what that is
[04:56] <elkng> smj: http://www.youtube.com/watch?v=BecJRawFxGo
[04:57] <wannabegeekster> smj: sorry, was afk.  Definitely not using pulseaudio.
[04:58] <wannabegeekster> I have tried using the two different devices that come up from arecord -l, but neither one of those record the audio.
[04:59] <smj> elkng: what does ffmpeg have to do with psytrance? :I
[05:05] <elkng> smj: is it works with frame rate more than 24 and all frames wont be seen while playing that video ?
[05:07] <smj> is that not just a static picture?
[05:57] <roboman2444> im trying to screencast to ustream, which i am successful at
[05:57] <roboman2444> but i want both my system audio and my mic being captured
[06:38] <elkng> smj: one picture
[06:38] <elkng> of henitalia
[06:38] <elkng> s/henitalia/genitalia
[06:50] <branden_> Anyone know how to copy multiple subtitles into mpeg? as in .mpeg
[06:55] <branden_> Has that time stamp bug with mkv been fixed yet?
[06:55] <branden_> like ffmpeg -i input.ext -acodec copy -vcodec copy output.mkv
[06:55] <branden_> some like avi will make a mess of things unless you put them in .mp4 first
[06:55] <branden_> then the mp4 to mkv in order to get it to work
[08:09] <unLab-Hackbox10> Hi guys is this no longer a valid option or something I missed compiling ffmpeg -f video4linux2 -standard NTSC -channel 1 -i /dev/video1 http://127.0.0.1:8000/cam2.ffm
[08:10] <unLab-Hackbox10> Unrecognized option 'standard'
[11:41] <codecowboy> hi. is it possible to extract two audio streams from a mov file  and mix them into a single file using only ffmpeg without sox?
[11:42] <Mavrik> use -map to just select audio streams?
[11:47] <codecowboy> Mavrik can you give me an example?
[11:51] <codecowboy> Mavrik if I do ""ffmpeg -i 2012-12-08-pt1.mov -map 0:0 -map 0:1 test1.m4a i only get one channel in the output
[11:51] <codecowboy> I probably mean 1 stream. The mov file contains two stereo audio streams
[11:52] <Mavrik> yeah, that's a distinct difference
[11:52] <Mavrik> one sec
[11:52] <Mavrik> codecowboy: you probably need to use the amix audio filter: http://ffmpeg.org/ffmpeg.html#amix
[11:53] <Mavrik> check also amerge, I'm not totally sure which one will do what you want
[11:53] <Mavrik> amerge looks like the more correct one
[11:54] <codecowboy> Mavrik does an input have to be a file or can it be a stream within a file?
[11:57] <codecowboy> he sample in the docs for the amerge filter is somewhat terse, and only
[11:57] <codecowboy> provides an example of merging two streams from separate files into one
[11:57] <codecowboy> dual channel stream
[12:11] <Underground78> Hello! I would appreciate some help understanding the possible impact of that change http://git.videolan.org/gitweb.cgi/ffmpeg.git/?p=ffmpeg.git;a=commit;h=8824a9ed2291d2b004dc641bd9ea8ad6f983466a on MPEG2 interlaced decoding
[12:12] <ubitux> you should ask this on the -devel channel
[12:12] <Underground78> ok thanks I'd forgotten about that
[12:35] <Hfuy> Hello. I need to rip a chunk out of a commercial DVD to a file that's editable (the decrypted mpeg-2 would be great). Can I do that with ffmpeg, ideally without having to rip the whole DVD?
[13:20] <germanstudent> Hey. I try to change specific audio (mp3) metadata (artist) without encoding the file again. Is this possible? -acodec copy?
[13:21] <klaxa> wouldn't it be easier to get an id3-tagging program?
[13:22] <germanstudent> tried mp3info but I get weird tags in some files, klaxa -.- Do you know a good one?
[13:23] <JEEB> thanks to elenril's work metadata like id3 tags can be edited in mp3 files
[13:23] <klaxa> not really, i get already tagged mp3 or flac :P
[13:23] <germanstudent> yay, JEEB. Can you tell me how?
[13:23] <JEEB> http://ffmpeg.org/ffmpeg.html see the -metadata option
[13:24] <germanstudent> thanks
[16:03] <Sashmo> hey everyone, quick question, I've been encoding live TS streams for a while now, and I think its time to smooth out my output, I can see a little freezing in the output, its not freezing, its looks almost like a frame rate issue, but its most noticeable when there are scrolls at the bottom of the screen, anyone have some ideas? http://pastebin.com/rTJZPYg5
[16:12] <Aristide> Hi !
[16:12] <Aristide> I have xrun buffer problems while screencasting ... How force audio and video to stay sync ?
[16:13] <klaxa> alsa?
[16:14] <klaxa> are you using alsa?
[16:14] <Aristide> Yes I use Alsa
[16:15] <Aristide> « ffmpeg -f alsa -ac 2 -i hw:0,0 -f x11grab -s $position -i :0.0 -acodec libmp3lame -ab 2048k -ar 48000 -vcodec mpeg2video -threads 0 -sameq -y output.avi »
[16:15] <klaxa> i know that on my end installing pulseaudio managed to stop underruns from occuring... it comes with quite the overhead though
[16:15] <Aristide> Ok
[16:16] <klaxa> might be completely unrelated though
[16:16] <smj> Aristide: you could try -async 1
[16:16] <klaxa> try that first
[16:16] <Aristide> I try to add -async 1 before test with pulseaudio
[16:17] <Aristide> smj: Where I put -async ?
[16:17] <smj> I'm not sure about that, or if it makes any difference
[16:18] <smj> I'd put it between input and output
[16:19] <Aristide> Again xrun buffer ><
[16:19] <Aristide> I try with pulseaudio
[16:19] <Aristide> ALSA buffer xrun.28 q=0.0 size=   49547kB time=00:00:42.52 bitrate=9544.1kbits/s \o/
[16:23] <smj> sure, but does it keep in sync?
[16:26] <Nick-S> ffmpeg -f image2 output-%05d.png -c:v libx264 output.ts doesn't work for me
[16:27] <Nick-S> unrecognized option 'c:v'
[16:27] <klaxa> old ffmpeg version
[16:27] <Nick-S> oh really...
[16:27] <Nick-S> not that old
[16:27] <Nick-S> but maybe old enough
[16:27] <JEEB> also if the version entry tells you that it's Libav, switch to the 'avconv' command
[16:28] <JEEB> as you have the libav project's binary then
[16:28] <Nick-S> SVN-r26400
[16:28] <JEEB> ok
[16:28] <JEEB> that's /old/
[16:28] <JEEB> like at newest, very early 2011
[16:28] <Nick-S> ok
[16:28] <Nick-S> shit :)
[16:28] <JEEB> what system are you on?
[16:28] <Nick-S> win x64
[16:28] <JEEB> ok, grab some zeranoe builds then
[16:29] <JEEB> http://ffmpeg.zeranoe.com/builds/
[16:29] <Nick-S> yep, thats what i'm using
[16:29] <JEEB> well you're using something /quite/ old if it's still SVN :D
[16:29] <JEEB> and not git
[16:35] <Nick-S> there is a really big difference in file size
[16:35] <Nick-S> 12mb to 20mb
[16:35] <Nick-S> spooky
[16:35] <Nick-S> what did they put inside
[16:36] <JEEB> see the library listing :D
[16:36] <JEEB> in most cases you won't need most of those things :)
[16:53] <Aristide> Hi again :)
[16:53] <Aristide> http://i.imgur.com/ArUG9.png I have test ffmpeg with pulse but I have this error :(
[16:58] <Aristide> Sorry I must go out I back later :)
[17:01] <funyun> hi. how do i force an aspect ratio? i am trying to encode a dvd that's 16:9 but it's keep encoding in 4:3. i've tried "-vf yadif=0,scale=854:480" and -r 16:9 but neither seem to work.
[17:09] <sacarasc> -r isn't ratio.
[17:09] <sacarasc> It's frame rate.
[17:13] <funyun> sacarasc: oh i see. so could -vf setdar='16:9' work?
[17:17] <Aristide> Hi again :)
[17:17] <funyun> nvm that worked
[17:19] <Aristide> http://i.imgur.com/ArUG9.png I have test ffmpeg with pulse but I have this error :(
[17:24] <neolynx> hello
[17:24] <neolynx> I have a question about libavcodec
[17:24] <neolynx> I try to get the mpegvideo extradata out of a mpeg elemetary stream
[17:25] <neolynx> I get pictures with avcodec_decode_video2
[17:26] <neolynx> but the AVCodecContext is not filled...
[17:26] <neolynx> but the AVCodecContext *extradata* is not filled...
[17:27] <neolynx> any hints on how to create this extradata ? I need it to fill the CodecPrivateData in matriska
[17:29] <neolynx> s/matriska/matroska/
[17:55] <cheusov> Hi. I have a h264 hd1080 video file and I'd like to benchmark VDPAU decoding (nvidia(4) driver work perfectly), that is, to skip audio and subtitle streams and decode video stream to /dev/null. Can anybody please suggest me ffmpeg args for this?
[17:55] <cheusov> ffmpeg -decoders shows h264 and h264_vdpau
[18:43] <Yulth> Hi everyone!
[18:53] <Yulth> Please, let me explain my goal: I need to stream encoded AAC audio to users from MP3 audio, but this streaming have to be in real-time. So, I need to feed users with a 3 seconds burst (in a similar manner IceCast does) to continue feeding they in real-time. Ffmpeg can convert from one stream to another without problems, but my question is: Is there any way to feed ffmpeg with 3 secs (and so read 3 secs ffmpeg's output at 100% CPU time) an
[18:53] <Yulth> d then continue feeding ffmpeg with -re option to read real-time audio output? Perhaps using -fflags nobuffer? Any ideas?
[19:02] <Yulth> any ideas? :)
[22:07] <Sashmo> hey everyone, quick question, I've been encoding live TS streams for a while now, and I think its time to smooth out my output, I can see a little freezing in the output, its not freezing, its looks almost like a frame rate issue, but its most noticeable when there are scrolls at the bottom of the screen, anyone have some ideas? http://pastebin.com/rTJZPYg5
[23:32] <Sashmo1> hey everyone, quick question, I've been encoding live TS streams for a while now, and I think its time to smooth out my output, I can see a little freezing in the output, its not freezing, its looks almost like a frame rate issue, but its most noticeable when there are scrolls at the bottom of the screen, anyone have some ideas? http://pastebin.com/rTJZPYg5
[00:00] --- Mon Dec 10 2012