[Ffmpeg-devel-irc] ffmpeg.log.20140913

burek burek021 at gmail.com
Sun Sep 14 02:05:01 CEST 2014


[00:43] <BtbN> Is it possible to tell ffmpeg to transcode in realtime?
[00:43] <c_14> -re
[00:43] <BtbN> Like, even if it can go 500 fps, it should stick with the input material framerate?
[00:43] <vlatkozelka> yep -re
[00:43] <vlatkozelka> that helped me alot btw c_14 :)
[00:43] <llogan> as an input option
[00:47] <BtbN> ah, it's an input option!
[00:47] <BtbN> yep, that's why i didn't find it propably
[00:49] <BtbN> wow, twitch realy didn't like me sending them an entire 20 minute video in like 30 seconds
[00:49] <berzerka> hi. i built the latest ffmpeg version because i want to link vlc to it. it seems that all symbols are stripped off the object file on installation.
[00:49] <BtbN> it's completely broken now, looping over the same 6 seconds since 5 minutes
[00:50] <berzerka> the version in the source tree shows all the symbols, but in the installed .so there are no symbols defined.
[00:53] <berzerka> just found --disable-stripping, lets give it a try..
[01:57] <berzerka> which ffmpeg version supplies libavcodec 55?
[02:00] <berzerka> oh, got it from http://www.ffmpeg.org/download.html
[02:06] <Baked_Cake> finally got my homegroup working
[02:06] <Baked_Cake> think my problem was boh pc's had the sameo name
[02:07] <Baked_Cake> oops
[05:01] <valder21> hey all wondering if somebody can do a quick code review on my audio decoder stuff.  I can't figure out how to add sound to my videos.  All of the videos come out silent even though I believe I am writing to the stream audio samples.
[05:01] <valder21> I've posted the issue on SO : http://stackoverflow.com/questions/25813484/what-am-i-doing-wrong-with-my-audio-writing-in-ffmpeg  There is a link there to the full source of my project.
[05:03] <valder21> I also get this error when I try to open my audio codec, I can't find any reference as to what it means: "Could not open audio codec: Experimental feature"  This happens in the open_audio function.
[07:52] <haspor> hello, anyone could help me with decoding adpcm_swf to pcm data ?
[08:37] <bencc> when trying to build on ubuntu 14.04 with --enable-x11grab I'm getting intrin.h: No such file or directory
[08:48] <relaxed> bencc: did you install build-essential?
[08:57] <bencc> relaxed: yes
[08:57] <bencc> relaxed: I'm trying to use this https://github.com/pyke369/sffmpeg
[08:59] <bencc> relaxed: your static build doesn't include enablex11grab? http://johnvansickle.com/ffmpeg/
[09:16] <Reelee> Can someone please help me use -map on MPTS stream to select specific audio channel? Here is part of the MPTS stream: http://pastebin.com/kRyxTLZC. Thank you!
[09:21] <relaxed> bencc: correct
[09:22] <Nosomy> -map 0:28 for get a mdk.
[09:22] <relaxed> bencc: apt-get build-dep libav-tools
[09:27] <michaelni> haspor, can you describe the problem and show us the code that fails
[09:28] <Reelee> Nosomy: first I use -map 0:p:11 to get Program 11, but when I use -map 0:28 as 2nd parameter, I get "Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument" and "sample rate not set"
[09:29] <haspor> all right, i have flv file that has audio stream (adpcm_swf), i want to decode that to raw pcm data, its 22050hz mono s16 stuff
[09:30] <haspor> but all i get is crackling and static noise
[09:30] <haspor> with mp3/aac it works just fine
[09:40] <Nosomy> last ffplay build,  still with problem of playback mkv files with hevc stream, 'm having to use an old version, which works well for this.
[09:50] <valder21> Hi all,  I am looking for help. I don't understand how to get my audio to be heard on my output video.  I'm pretty sure I'm following examples I've seen around the web closely.  Am I not accounting for PTS/DTS properly?  All of my videos come out silent.  When I try to write out an audio frame it results with an error (code -22). "Invalid Argument" I can't seem find what that really means if I'm calling
[09:50] <valder21> avcodec_decode_audio4()
[10:11] <valder21> ?
[10:13] <Fjorgynn> :/
[10:13] <Fjorgynn> I am sleeping
[10:13] <Fjorgynn> please be atient
[10:13] <Fjorgynn> patient
[10:23] <Nosomy> ffplay version N-66249-gbcac0f4 http://pastebin.com/2aFqMywt <- mkv with hevc, playback fail
[10:40] <bencc> relaxed: I'll try it. thanks
[10:54] <bencc> I'm trying to capture desktop and sound with
[10:54] <bencc> ffmpeg -video_size 1024x768 -framerate 25 -f x11grab -i :0.0+100,200 -f alsa -ac 2 -i pulse output.flv
[10:54] <bencc> getting Unknown input format: 'alsa'
[10:54] <bencc> full log http://dpaste.com/0PTADJQ
[10:55] <bencc> this is how I built ffmpeg http://dpaste.com/3JQN84J
[12:55] <relaxed> bencc1: install libasound2-dev and recompile ffmpeg
[12:56] <relaxed> it will tell you the supported indevs in configure's output. Make sure alsa is listed.
[13:18] <bencc1> relaxed: works thanks
[13:19] <bencc1> I'm using the following command but the audio and video are out of sync
[13:19] <bencc1> /usr/bin/ffmpeg -f pulse -ac 1 -i alsa_output.pci-0000_00_05.0.analog-stereo.monitor -f x11grab -framerate 15 -s 1280x960 -i :0.0 -acodec pcm_s16le -vcodec libx264 -preset:v ultrafast -crf 0 -threads 0 capture.mkv
[13:19] <bencc1> what can I do to make the video and audio in sync?
[13:45] <relaxed> bencc1: try -r 60 instead
[14:06] <haspor> here is the code im currently using to get audio stream from flvs: https://gist.github.com/anonymous/41155aa9d9a1ff933c99
[14:07] <haspor> i have no idea what might be wrong
[15:03] <mrskman> Hi, is there any way how to set default audio stream in mkv?
[15:05] <Peppery> Hi there, I am using this command to rotate and overlay a PNG over a video http://pastebin.com/ebWWj4gP - is there any way to have the PNG fill the entire video rather than manually specifiyng width and height?
[15:18] <c_14> Peppery: none I know of
[15:19] <Peppery> thanks, c_14. that's the conclusion I was coming to
[15:22] <c_14> mrskman: technically with `-metadata:s:a:0 default=1', but iirc ffmpeg does not currently write it correctly. You can use mkvtoolnix to set it.
[15:31] <mrskman> same with default/forced subtitles?
[15:32] <c_14> yep, ffmpeg will copy them if the input file has them set as default/forced, but it won't set them if they're not.
[15:33] <mrskman> ok, thanks
[16:41] <gcl5cp> is there a python biding updated?
[16:42] <klaxa> i don't think so
[17:34] <bencc1> relaxed: "-r 60" instead of "-framerate 16" ? I'll try it. can you explain why?
[19:14] <Mic_> Hi all. I'm new to ffmpeg. I am a student doing a case study on the project. I have the following question: I'm trying to gain some insight into the security vulnerabilities that were fixed in previous versions on the security page of the ffmpeg website, but I don't understand what's written there. It just shows something like the following:  CVE-2014-5271 60bfa9154d0084bc8b007b984051a6bb82d9652c
[19:15] <Mic_> What exactly does this mean and how can I get some more information about what was fixed?
[19:15] <Mic_> Thanks to anyone who can help!
[19:16] <JEEB> git clone git://git.videolan.org/ffmpeg.git && cd ffmpeg && git show 60bfa9154d0084bc8b007b984051a6bb82d9652c
[19:16] <JEEB> or http://git.videolan.org/?p=ffmpeg.git;a=commit;h=60bfa9154d0084bc8b007b984051a6bb82d9652c
[19:17] <JEEB> and then looking at the diff you can see what changed in both cases
[19:40] <haspor> anyone could finally help with this: http://pastebin.com/veHU8VBx, why it fails to decode ADPCM_SWF
[19:43] <Mic_> oh i see. thanks JEEB
[21:09] <bencc1> when capturing the screen, is it possible to get the whole screen instead of specifying the resolution?
[21:09] <bencc1> I'm using
[21:09] <bencc1> ffmpeg -f pulse -ac 1 -i alsa_output.pci-0000_00_05.0.analog-stereo.monitor -f x11grab -framerate 15 -s 1280x960 -i :0.0 -acodec pcm_s16le -vcodec libx264 -preset:v ultrafast -crf 0 -threads 0 capture.mkv
[22:36] <valder21> can somebody point me to an example of taking audio from an MP4 file and splicing it into another?  I've tried a few different examples I've found off SO and ffmpeg examples.  I just get silent videos.  Here's my current code:
[22:36] <valder21> http://pastebin.com/4ax7XMur
[22:38] <valder21> the work is done in the renderMovieRequest function.  primarily between lines 995 and 1038
[22:38] <valder21> do I need to convert the audio context to another format first?  Am I missing a step?
[22:44] <_dunno_> i have a huge file, like 10h+, and want to cut chunks of that file to different files: ffmpeg -i long_vid.mpeg2 -ss start1 -t end1 output1.avi ... -ss startn -t endn outputn.avi is this possible? or in other words - does ffmpeg know about such thing as a 'cutlist'?
[23:40] <gcl5cp> pip search ffmpeg --> ffms, wffmpeg, ffmpegwrapper, myffmpeg. are they updated?
[00:00] --- Sun Sep 14 2014


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