[Ffmpeg-devel-irc] ffmpeg.log.20120305

Tue Mar 6 02:05:01 CET 2012

[01:40] <_|Nix|_> Hi! Can someone please help me stream from my webcam to ffserver?
[01:40] <_|Nix|_> This: ffmpeg -f alsa -i hw:0,0 -f video4linux2 -i /dev/video0 http://localhost:8090/feed1.ffm
[01:40] <_|Nix|_> gives me Error while opening encoder for output stream #0.1 - maybe incorrect parameters such as bit_rate, rate, width or height
[01:41] <_|Nix|_> What should the output parameters be for ffserver?
[01:42] <_|Nix|_> The feed does not have any bit_rate rate, width, or height parameters at all.
[03:29] <diegoviola> hi
[03:30] <diegoviola> if i encode a video in webm (vpx/vorbix) format, then i upload that video to youtube, will that play in html5/flash, etc?
[03:30] <diegoviola> *vorbis
[03:30] <diegoviola> sorry if i'm being off-topic
[03:31] <sacarasc> If you encode your video to anything and upload it to youtube, they'll convert it to work with html5 and flash.
[03:31] <diegoviola> thanks
[03:32] <diegoviola> ffmpeg is awesome
[03:48] <herdingcat> hi, is that possible to run ffmpeg without status output? because I wanna run it in a script.
[03:53] <herdingcat> or r I can just put it in background?
[04:02] <grepper> herdingcat:  -loglevel quiet
[04:04] <grepper> but not having output doesn't seem too great to me, how will you debug it if something isn't right ?
[04:06] <grepper> you could also do > output.txt 2>&1 , which would keep it quiet but also give a fallback log
[04:16] <herdingcat> grepper, great. thanks ,ate
[04:38] <herdingcat> grepper, mate, -loglevel quiet is not useful.
[04:39] <burek> then ffmpeg .. 2>/dev/null
[04:39] <burek> it will make it quiet
[04:41] <herdingcat> thanks burek
[04:42] <burek> :beer: :)
[07:54] <perrth> hi, have anyone tried  -vf "frei0r=facebl0r" with ffmpeg? does it works (openCV)?
[07:54] <perrth> it should blur detected face from video input
[08:10] <frogs> compilation is broken !
[08:10] <frogs> change to libavcodec/cook.c, changes return type of function decouple_info from void to int, but contains a plain "return;"
[08:11] <frogs> libavcodec/cook.c:773:9: error: non-void function 'decouple_info' should return a value
[09:34] <shroomM> is there any way in ffmpeg to generate dvb subtitles from existing idx/sub vobsub subtitles ?
[10:39] <trupheenix> hi. i want to know how i can find out the keyframes in a video?
[10:52] <Tjoppen> ffprobe -show_packets $FILE|grep flags=K
[10:52] <Tjoppen> maybe add -A and -B to grep
[10:53] Action: cbsrobot hands Tjoppen a "master of ffprobe" batch
[10:54] <ubitux> there is also video filter like showinfo and select to help dealing with key frames
[10:56] <ubitux> Tjoppen: no need to -A -B with grep, you can use the -print_format compact
[10:56] <Tjoppen> ah
[10:57] <ubitux> showinfo is nicer imo though
[10:59] Action: cbsrobot : hands ubitux a "übermaster of ffprobe" batch
[10:59] <ubitux> @_@
[11:03] <trupheenix> Tjoppen, i meant how i can use libavcodec libavformat to do this?
[11:03] <Tjoppen> well, you can av_read_frame() and check pkt.flags
[11:37] <brontosaurusrex> has anyone tested utvideo encoder 4:2:2, 4:4:4, 4:2:0 ?
[12:05] <trupheenix> Tjoppen, tried using ffprobe. i don't understand what the output means?
[12:06] <Tjoppen> what are you trying to do?
[12:07] <trupheenix> Tjoppen, i did ffprobe -show_packets $FILE|grep flags=K
[12:30] <alfadir> hi, have a file that dies with : Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2970 >= 2970.. any tip on how to fix the file ? it fails in this check "st->cur_dts >= pkt->dts" in libavformat/utils.c 3174 compute_pkt_fields2
[12:31] <alfadir> -vcodec copy -copyts -acodec copy  is used
[13:04] <stonie> hi all.. i'd like to encode into x264 hd videos from a dvc/shoulder cam .. thats fine by me so far, except the audio stream, because its recorded with 48khz..
[13:04] <stonie> how should i encode the audio to get the best out of it?
[13:04] <brontosaurusrex> stonie: what OS?
[13:04] <stonie> ffmpeg on linux AND win
[13:05] <stonie> ..some use OSX tho, but i got no idea on that yet
[13:05] <brontosaurusrex> stonie: on win or linux you can use nero AAC enc, a bin is/was provided by nero, video is then encoded/muxed with ffmpeg
[13:05] <brontosaurusrex> or use one or the other internal AAC or FAAC
[13:06] <brontosaurusrex> on OSX i use apple AAC encoder
[13:07] <brontosaurusrex> whats wrong with 48 kHz ?
[13:09] <stonie> i tried with 192kbs aac/libvo_aacenc .. but it seems to have a bad resolution and some silence sounds arent encoded
[13:10] <brontosaurusrex> stonie: a 2ch audio is original, or 5,1?
[13:11] <stonie> 2ch
[13:12] <stonie> just atmo and mic
[13:12] <brontosaurusrex> right
[13:12] <brontosaurusrex> well, test either nero AAC or apple AAC
[13:12] <brontosaurusrex> both is possible on win, nero is possible on nix
[13:13] <brontosaurusrex> or/and FAAC
[13:13] <stonie> ok ty ill try some more .. but you dont think it has something to do with the audio bitrate? 192 should be enough i thought
[13:13] <brontosaurusrex> it is
[13:13] <stonie> k
[13:13] <stonie> tyvm
[13:14] <brontosaurusrex> AAC should be transparent at around 100 kbps (with decent encoder) i think
[13:15] <brontosaurusrex> what is the exact cli that you used for libvo_aacenc?
[13:46] <cbsrobot> stonie: on osx you can also use afconvert
[13:47] <ubitux> they stole the name of the ffmpeg audio filter!
[13:50] Action: cbsrobot calls his local sopa representativ 
[14:38] <speedup_audio> guys is there a way for me to speed up a bunch of audio files?
[14:50] <luc4> Hi! I'm using ffplay on ARM to play some wma, but I noticed that over a certain bitrate, alsa reports repeatedly underruns. Anyone who experienced the same?
[15:07] <stonie> cbsrobot, ok thanks for the tipp
[16:05] <luc4> Hi! I'm using ffplay on ARM to play some wma, but I noticed that over a certain bitrate, alsa reports repeatedly underruns. Anyone who experienced the same?
[19:05] <Freakshow> can I use ffplay to pull bits from a unix domain socket? seeing some limited results in the google searches... but nothing substantial
[19:10] <Freakshow> seeing this: http://web.archiveorange.com/archive/v/yR2T4qzzjJxem91xfV7Q
[19:16] <rhizmoe> hi all
[19:16] <rhizmoe> can ffmpeg's text features apply character along an arbitrary (bezier) path?
[19:17] <rhizmoe> plural "characters," natch
[19:33] <cbsrobot> Freakshow: just try it out ...
[19:33] <cbsrobot> rhizmoe: no
[19:34] <cbsrobot> rhizmoe: but patch welcome :-)
[19:35] <Freakshow> cbsrobot: can you elaborate on 'just try it out'? I haven't had a chance to completely read through that particular post, but is the method valid for getting a quick glimpse of the running encode i.e. outputting to both the domain socket and the desired output of ffmpeg?
[20:58] <funkster> im screen recording with ffmpeg and its working great, i looking to record a specific part of my screen within a window, instead od guessing/trial by error, is there a way I can tell what the offsets of recording will be?
[21:02] <relaxed> funkster: xwininfo
[21:05] <pasteeater> funkster: you might like ffcast. it has a "select the window or area you want to record" option, IIRC.
[21:06] <pasteeater> https://github.com/lolilolicon/FFcast2
[21:16] <cbsrobot> Freakshow: what do you want to achive ?
[21:16] <cbsrobot> what does "getting a quick glimpse" mean ?
[21:41] <Freakshow> cbsrobot: say for instance, I start an encode and then want to view it as it occurs... but only when I select the option to view... it can drop the data the rest of the time..
[21:42] <rhizmoe> cbsrobot: i'll see if i can eventually a) learn C well enuogh (again ;) and b) get the time :)
[21:43] <Freakshow> in my cli for ffmpeg, I'm thinking an output to a domain socket, and then the rest to the actual ingest point...
[21:44] <tck9> can ffmpeg to swf -> flv conversion or swf -> mp4?
[21:48] <cbsrobot> rhizmoe: I have some ideas about it - ping me when you have time
[21:48] <cbsrobot> Freakshow: there are options to use when encoding
[21:48] <cbsrobot> press h to see them (whil encoding)
[21:49] <rhizmoe> tck9: http://forum.videohelp.com/threads/309773-Extracting-video-from-SWF might help
[21:49] <Freakshow> hmm... press 'h' where?
[21:49] <cbsrobot> Freakshow: while encoding
[21:51] <Freakshow> the encode is being called from a script... pressing 'h' during the encode isn't possible
[22:07] <giany> anyone knows why i get this on ffmpeg 0.10:
[22:07] <giany> libavcodec/libavcodec.so: undefined reference to `x264_encoder_open_120'
[22:08] <pasteeater> giany: you probably have an old x264 (or -devel) files installed along with a newer one
[22:09] <pasteeater> see topic for compile guide if you're using ubuntu
[22:12] <cuzzo> Will FFmpeg decode with hardware acceleration on the Raspberry Pi?
[22:14] <rainmaker1> Hi, I have same strange artifacts on screen when transcoding from mpeg2 to h264, how can I find out if those errors have to do with source of the stream (I am using live stream udp) or with ffmpeg/x264 or with stars on the sky :)
[22:48] <EasyAt> Hey guys, I am not sure this is the place to ask.  I have a collection of elementary stream files.  I am writing a website that people can watch an undetermined amount of video.  I need to be muxing on the fly as the person is streaming.  Is this possible?
[22:49] <EasyAt> I used to ask them the duration and mux that many files.  I would rather have them watch it, then pick a start and end time after they have found it. and then produce the final file
[22:56] <cbsrobot> Freakshow: well I was only sugessting
[22:56] <Freakshow> sorry cbsrobot: if the application is running from script, how would you suggest I access that output?
[22:57] <Freakshow> I mean, I'll give it a shot on a stand alone encode just to see what you're referencing
[22:57] <Freakshow> and go from there
[22:57] <cbsrobot> maybe you can add a -vf showinfo and write that to a temp buffer or something like that
[22:57] <cbsrobot> what language are you using ?
[22:57] <Freakshow> simple shell script at this point... nothing fancy
[22:58] <Freakshow> -vf... checking
[23:29] <flaxo> hi, some help with dvd-subtitles needed!
[23:31] <flaxo> i seem to be unable to convert an .srt file to a working dvdsub coded subtitles within a .vob
[23:32] <flaxo> nothing found on google or FAQ that fits! any help would be aprechiated
[23:46] <chuck_> hello all, i have issues while trying to extract a specific segment out of a video. i enter this command : ffmpeg -sameq -ss <some_time> -t <some_duration> -i <some_filepath> <some_other_filepath>
[23:47] <chuck_> the issue is that it seems that ffmpeg keep scanning the movie more than i need. and when i stop the process and that i play the obtained video file, it is way too much long
[23:48] <cbsrobot> flaxo: share your command
[23:49] <pasteeater> chuck_: dont use sameq. it does not mean "same quality". also, the behavior of ss can change whether you use it as input or output option
[23:49] <cbsrobot> chuck_:  update ffmpeg to the latest version
[23:49] <chuck_> cbsrobot : i've just downloaded it, i think its at it's last version
[23:49] <pasteeater> chuck_: http://ffmpeg.org/pipermail/ffmpeg-user/2011-November/002976.html
[23:50] <chuck_> pasteeater : what changes in the behavior can occur ?
[23:50] <cbsrobot> chuck_:  ok - so it's the sameq option
[23:50] <pasteeater> see link
[23:50] <pasteeater> also, add "-c copy" as an output option. this will "copy and paste" the input to the output instead of re-encoding which, i assume, is what you want
[23:51] <chuck_> ok so i can just take -sameq out of the command and it might work ?
[23:51] <pasteeater> if your ffmpeg is too old, and i can't tell because you provided no console output, then use "-vcodec copy -acodec copy" instead of "-c copy"
[23:52] <pasteeater> no. do this: ffmpeg -ss 10 -t 32 -i input -c copy output, or ffmpeg -t 32 -i input -ss 10 -c copy output
[23:52] <chuck_> i have ffmpeg version 0.7.3-4:0.7.3-0ubuntu0.11.10.1
[23:52] <pasteeater> then use "-vcodec copy -acodec copy" instead of "-c copy" as shown in my examples
[23:53] <cbsrobot> chuck_: do it the right way: http://ubuntuforums.org/showthread.php?t=786095
[23:54] <pasteeater> see if my examples work first. if not then you may have to compile as shown in the link cbsrobot supplied
[23:55] <chuck_> ok thanks pasteeater and cbsrobot. i'm gonna try all that right now
[23:55] <pasteeater> (also you're using "ffmpeg" from libav, not ffmpeg from FFmpeg project)
[23:56] <chuck_> pasteeater : what do you mean ? whats libav ?
[23:58] <cbsrobot> chuck_: same same but different
[23:58] <chuck_> haha ok
[00:00] --- Tue Mar  6 2012