[Ffmpeg-devel-irc] ffmpeg.log.20140802

burek burek021 at gmail.com
Sun Aug 3 02:05:02 CEST 2014


[01:04] <hotwings> ffmpeg git down at the moment?
[06:49] <elfer> if i have a video file, and the audio is not align with the video.. how would i align it properly? like if somebody on the video is talking, you see their mouth moving, but you do not hear the sound until .5-1.0 seconds later. how can i re-align that video's audio?
[06:49] <elfer> is there a different name for it?
[06:50] <elfer> ...rip the audio and compile the video and audio together, in a new file? or is there an ffmpeg function or even ... software linux or windows based that can accomplish this?
[07:55] <Xardas> Hello, I've got a problem with broken webms that has persisted through multiple versions of ffmpeg (x86 and x64 build from the latest version and one from like 2 months ago) and I don't understand how to fix it. Does ffmpeg save information somewhere else than the respective folder?Do installed Codec packs affect it? I am running Windows Ultimate SP1 x64 and my webms work fine in Chrome but are broken in Firefox.
[08:50] <slowguy> i want to cut a file from a precise time but i want to copy the codec too
[08:51] <sfan5> thats not possible
[08:51] <sfan5> if you want to cut video/audio you need to re-encode it
[08:55] <slowguy> sfan5: then maybe re-encode only upto next keyframe
[08:55] <slowguy> is that possible?
[08:55] <sfan5> I'm pretty sure that would be possible
[08:55] <sfan5> but I know of no programs that implement this
[08:56] <slowguy> so i need to write my program using libav*?
[08:57] <sfan5> if you want to do precise cutting without re-encoding everything?
[08:57] <slowguy> yeah :(
[08:57] <sfan5> it's mostly codec specific, so you don't need to use libav
[09:00] <slowguy> actually the original file will also be created by me..any suggestion which format would be most helpfull in this
[09:01] <slowguy> i just want to cut the file precisely without re-encoding the whole file coz that will take too long
[09:02] <slowguy> sfan5: i have another idea which i would like to discuss
[09:03] <slowguy> is there any way to find the position of next keyframe after a certain timestamp?
[09:04] <slowguy> so i can give two commands.. one with precise cutting from 14 to 19 with reencoding
[09:04] <slowguy> and then from 19 to endoffile with fast seek and copy codec
[09:05] <slowguy> and then merge these two files with concat demux..would that work?
[09:06] <anshul_mahe> What does full form of VSCFR in VSYNC_VSCFR (format_video_sync) in ffmpeg.c
[09:06] <anshul_mahe> I know FR stand for fame rate
[10:42] <sfan5> slowguy: that would probably work
[15:27] <xreal> Is LAV based on ffmpeg ?
[15:28] <slowguy> LAV= ?
[15:28] <ubitux> All LAV Filters are based on the FFmpeg multimedia libraries (licensed under GPLv2)
[15:28] <ubitux> quoting the main page of the site
[15:42] <xreal> ubitux: I wonder, why LAV doesn't have nice filters like ffmpeg. Did they remove them? Brightness etc.
[15:43] <ubitux> i don't know
[15:43] <ubitux> why do you use LAV?
[15:47] <xreal> ubitux: it's default when you install my favourite codec pack :D
[15:47] <xreal> K-Lite Codec Pac
[15:49] <Deffie> hello everyone, i've adapted a pipeline for a chinese cctv dvr which auths, trashes the received custom header and writes the h264 stream to a fifo which i'm trying to open with mplayer/avplay/ffmpeg/vlc, the only who makes some step is mplayer specifying demux h264, now the problem is that I don't know much of ffmpeg and video formats, can you help me understand which parameters can help me ? theres an image showing what i get with mplayer http://pa
[15:53] <Deffie> ok fps 12 helped a lot :)
[15:56] <Deffie> http://pbrd.co/1sdismi :)
[15:58] <xreal> ubitux: they're argumenting: "ffdshow only has DXVA, it does not support CUDA." "ffdshow only uses a subset of its functionality"
[16:17] <BlackBishop> anyone can tell me what option/param should I use for libass in conjuction with -ss for the input ? ( I want to start the video from a certain offset and so should the subtitles )
[18:54] <anshul_mahe> While transcoding video of my webcam, sometimes I am having delta(ffmpeg.c) value as high as 6000-7000, and as result ffmpeg start duplicating frames and my video freeze
[18:55] <anshul_mahe> is there any workaround for this problem
[18:56] <anshul_mahe> Do we need to compile libSDL again if we upgrade kernel, just now ffplay crash in libSDL, i upgraded my kernel to torwald git repository
[18:57] <anshul_mahe> is any one using kernel 16.0+rc+7
[18:57] <anshul_mahe> sry rc7 or near about and having same issue with ffplay
[19:27] <sfan5> anshul_mahe: if you update certain things you may need to compile sdl and/or ffplay
[19:31] <anshul_mahe> sfan5,thanks I will give that a try ,but as of now it looks like I have to compile lots of utilites
[20:27] <Nopik> hi all
[21:10] <t4nk681> I hope this is the correct place to ask this question, but is there a way to output via std or something, the waves generated with ffplay ie. --showmode 1?
[21:49] <Dominique_Michel> Hi all, I done a VCD rip of a music VCD. It was a difficult rip to do, because of scratches on the disk. Finally, usingg different solution, I was able to rip all the songs.
[21:51] <Dominique_Michel> One of them is 15 min 13 sec long, when playing it, as example with mplayer, I get the correct lenth and I can play it without trouble.
[21:51] <Dominique_Michel> I extracted the audio in it with
[21:52] <Dominique_Michel> ffmpeg -i msong.mpeg -vn -acodec copy mysong.mp2
[21:53] <Dominique_Michel> it worked, but when I play it, it play but the duration is wrong, only 5 min 01 sec
[21:55] <Dominique_Michel> I try different software like mplayer and alsaplayer, and the result is always the same, it show a duration of 5 min 1 sec, but can be played all the 15 min 13 sec
[21:56] <Dominique_Michel> After 5 min 1 sec, if I try to seek, the play resume immediately with all players I try.
[21:57] <Dominique_Michel> I try later to transcode from mp2 to ogg, because alsaplayer is not able to correctly play the mp2 file, and the issue remain.
[21:57] <Dominique_Michel> Is it something I can do, or is it a bug that should be reported somewhere?
[22:04] <Dominique_Michel> http://pastebin.com/5J0QDRqR is a paste of ffmpeg -i from the mpeg file
[22:06] <Dominique_Michel> http://pastebin.com/yAgVrzwx the same from the ogg file
[22:14] <Dominique_Michel> Strange, I just redone the conversion from mpeg to mp2, and get the correct file length.
[22:22] <Dominique_Michel> And now I have the same visible length... Sorry for the noise, must be something else.
[22:23] <Dominique_Michel> After later conversion to ogg, and I can seek into the whole file.
[00:00] --- Sun Aug  3 2014


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