[Ffmpeg-devel-irc] ffmpeg.log.20140821

burek burek021 at gmail.com
Fri Aug 22 02:05:01 CEST 2014


[00:00] <RaZoR37> okay
[01:33] <vlatkozelka> Im trying to save a udp stream containing TV channels onto segments ... the recording is fine but , the timestamp is being reset so start is 00:00:00 , everything else is good . I tried -copyts but didnt work and made things worse , now it records like 30 1 second long ts files then  the rest the time i need but still timestamps are reset .
[01:33] <vlatkozelka>  http://pastebin.com/pRWBaSad
[01:33] <vlatkozelka> can anyone help me with this ?
[06:16] <profit___> so i'm having a bad time trying to stream audio + a png to an RTMP server.
[06:16] <profit___> it stops immediately.
[06:17] <profit___> http://hastebin.com/bogecikiju.mel is what i try to run, and it immediately stops (hence the output)
[06:18] <profit___> i've tried including -loop 1 before the PNG file to no avail either
[08:14] <sekon> Hello,
[08:15] <sekon> I am trying to compile ffmpeg with libvo_aacenc
[08:18] <Zhenya> Hello
[08:18] <Zhenya> Who knows how to set a subtitle stream as default & forced?
[08:19] <ParkerR> Zhenya, forced as in forced on or forced as in hard coded?
[08:20] <Zhenya> ParkerR: By using mediainfo. I see two flags per stream. default:no  force:no. So I want to open the subtitle by default
[08:21] <ParkerR> Maybe a bug https://trac.ffmpeg.org/ticket/2402
[08:21] <Zhenya> ParkerR: I have tried -metadata:s:0 default=1  ,but then I got two default flags...  default:no, DEFAULT:1
[08:22] <ParkerR> "What is missing afaict is a possibility for the user to mark streams as default streams, an alternative is to always set the first stream as default in the Matroska muxer, I am not completely convinced that this is the best solution, consider sending a patch if that is what you want."
[08:24] <Zhenya> ParkerR: I am not sure that I have the ability to do the fix....
[08:24] <ParkerR> Not saying you do. I was just copy and pasting the first comment :P
[08:24] <Zhenya> ParkerR: Do you know how to make the subtitle as the first stream so it will be default on?
[08:25] <ParkerR> Not sure
[08:26] <Zhenya> ParkerR: Opened 17 months ago
[08:32] <klaxa> Zhenya: afaik ffmpeg does not support that feature yet, use mkvtoolnix for now
[08:33] <Zhenya> klaxa: Thanks
[09:38] <Buddy2> Hi, I would like to demux the AC3 stream of a ts file with 2 audiostreams, I tried the map function but sometimes the AC3 stream is 0:1 and sometimes the AC3 stream is 0:2   How can I make sure I always only demux the AC3 stream of the file?
[09:38] <Buddy2> ffmpeg -i input.ts -acodec copy -map 0:2 -vn audio.ac3
[09:39] <Buddy2> mediainfo always says that the AC3 stream is secondary audio
[09:39] <Buddy2> so I don't understand why ffmpeg sees it as primary sometimes
[09:39] <Buddy2>     Stream #0:1[0x2c9](eng): Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, stereo, fltp, 192 kb/s
[09:39] <Buddy2>     Stream #0:2[0x265](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 192 kb/s
[10:37] <alina-emergency> hey all for example if i want to cut a fragment like 34:20 - 36:20 and export that part as mp4 is that possible to do?
[11:12] <myubuntu> Can ffmpeg do audio mixing?
[11:16] <ubitux> yes
[11:21] <myubuntu> But I can't find any code.
[11:26] <ubitux> http://ffmpeg.org/ffmpeg-filters.html#amerge
[11:26] <ubitux> http://ffmpeg.org/ffmpeg-filters.html#amix
[11:28] <myubuntu> thanks, I 'll check
[12:51] <bigzed__> Hi, does anyone of you know if FFmpeg supports DnxHD in an MXF container created by Avid?
[13:06] <relaxed> bigzed__: I believe so
[13:08] <bigzed__> relaxed, I have exactly such a file here, but this is what FFmpeg says about it without encoding it. http://pastebin.com/vHz1cT2F
[13:08] <bigzed__> Do I have to specify special options for it?
[13:10] <relaxed> do you have any others files to test?
[13:12] <relaxed> https://code.google.com/p/ffmbc/ might have better support for them.
[13:17] <bigzed__> checked with FFmbc as well, but it  stops with this http://pastebin.com/Ce1nQa7N
[13:17] <bigzed__> do you know if it is possible to specify the pixel format by hand?
[14:07] <needffmpeghelp> hi
[14:07] <needffmpeghelp> I am working on adding an overlay to either a video or an image
[14:07] <needffmpeghelp> if I want to overlay an image or a video on top of another video, that seems to work with:
[14:08] <needffmpeghelp> ffmpeg -y -i image.jpg -strict experimental -vf "movie=video2.mp4, scale=90:-1 [watermark]; [in][watermark] overlay=main_w-overlay_w-36:main_h-overlay_h-48 [out]" -c:v libx264 -profile:v baseline -acodec aac videoOutput.mp4
[14:08] <needffmpeghelp> sorry, that doens't work
[14:09] <needffmpeghelp> ffmpeg -y -i video.mp4 -strict experimental -vf "movie=video2.mp4, scale=90:-1 [watermark]; [in][watermark] overlay=main_w-overlay_w-36:main_h-overlay_h-48 [out]" -c:v libx264 -profile:v baseline -acodec aac videoOutput.mp4  works
[14:09] <needffmpeghelp> that works
[14:09] <needffmpeghelp> but if I put the image as the first input, then I end up with a 1 frame video
[14:09] <needffmpeghelp> and if I do -loop 1 at the beginning, then the video never stops
[14:10] <relaxed> bigzed: yes, ffmpeg -pix_fmt $format -i input
[14:10] <needffmpeghelp> basically what I want is for the video to be as long as the longest video (either the video or the overlay), and if it's an image as the background then I want the image to display for the full length of the other input
[14:12] <relaxed> needffmpeghelp: it's recommended to use -filter_complex now for overlays and watermarks
[14:19] <needffmpeghelp> ok, I'll try read up on it a bit and come back if I still need help
[14:33] <Buddy2> how can I demux all audiostreams from a ts file without specifying outputfiles? Just dump everything that's audio? :)
[14:39] <slowguy> i need to print all the keyframe timestamp in a file..i am using ffprobe but its very slow
[14:40] <slowguy> is it possible to make ffmpeg dump this info at the time of encoding itself?
[15:16] <davis> hello
[15:17] <davis> im trying to follow along with the ffmpeg basics book. I'm also looking at the online ffmpeg docs.
[15:18] <davis> early in the book and on this page here
[15:18] <davis> https://www.ffmpeg.org/ffmpeg.html#Synopsis
[15:18] <davis> is a description of how to overlay two videos.
[15:18] <davis> the approach is similar, it looks this
[15:19] <davis> ffmpeg -i foo.mkv -i goo.mkv -filter_complex 'overlay' boo.mkv
[15:19] <davis> however, when I do this, I get an error about "Unrecognized option" filter_complex
[15:20] <davis> ive tried using the longer command syntax describe but it still fails.
[15:20] <ubitux> but you're probably just outdated, like with a several years old ffmpeg
[15:21] <ubitux> you probably have a ffmpeg that is at least 3 years old
[15:21] <davis> hmm. I was using the one built in to ubuntu distro. Should I use a custom site or build from source?
[15:21] <ubitux> right, so you're not even using ffmpeg but a fork, so yeah no surprise
[15:21] <ubitux> you'd better build from the source yes
[15:22] <davis> ok, i'll try to pull frm git and see if I can get it to build on this distro
[17:43] <relaxed> davis: or http://johnvansickle.com/ffmpeg/
[19:45] <lenarhoyt> hi, I'm trying to convert Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default) to mp3
[19:46] <lenarhoyt> however the file turns out to be twice as long and some parts repeat
[19:51] <lenarhoyt> http://pastie.org/private/etle8g5qjbpyosoelqrya
[19:52] <relaxed> llogan: what did you need?
[19:52] <lenarhoyt> A.m4a is 08:00:33.35, while B.mp3 is about 18:18:24.00 long
[19:54] <lenarhoyt> 2,25 is an odd factor :/
[19:55] <lenarhoyt> hm, ffmpeg recognizes the length correctly
[19:55] <lenarhoyt> its only apples mp3 decoder
[19:56] <lenarhoyt> http://i.imgur.com/sVUs6ZQ.png
[19:57] <lenarhoyt> http://pastie.org/private/ebgjyyvo9ydrcafeidscya
[20:02] <llogan> relaxed: burek seems to have vanished, and his builds have vanished. i was thinking of providing 32 builds. got a script i can base if off? </lazy>
[20:02] <llogan> i mean his builds have halted
[20:04] <llogan> lenarhoyt: might be bug https://trac.ffmpeg.org/ticket/2697
[20:04] <relaxed> I can add 32bit builds this weekend
[20:04] <llogan> ok, that works too
[20:04] <llogan> thanks
[20:04] <llogan> ping me and i'll update the download page
[20:05] <relaxed> will do
[20:12] <brontosaurusrex> is something like "ffprobe -show_frames -of compact=p=0 -f lavfi "movie=MOVIEFILENAME,select=gt(scene\,.4)" > MOVIEFILENAME.csv" doable with ffmpeg as well, or must I use ffprobe?
[20:13] <anshul_mahe> no not possible with ffmpeg, you can refer man  ffmpeg
[20:14] <anshul_mahe> -show_frames is only possible with ffmpeg
[20:14] <anshul_mahe> is libavfilter thread safe.
[20:15] <anshul_mahe> ?
[20:18] <anshul_mahe> When i call avfilter_graph_free while using all input filter, it gives me seg fault
[20:20] <rudi_s> mencoder supported -vobsoubout to dump the subtiles as .idx and .sub files. Is this still possible with ffmpeg?
[20:20] <rudi_s> I tried to convert the .vob to .mkv, but it seems the idx-"part" is not correctly transferred, as mkvextract doesn't let me extract the .idx/.sub from the resulting mkv file.
[20:20] <rudi_s> (codecprivate seems to be missing.)
[20:47] <lameiro> hi. I am running the following command line ( http://pastebin.com/nWk2swUd ) with latest zeranoe windows 32-static build and i get videos shorter than I expect - 60s expected, 59.1s generated according to mediainfo. I see in the ffmpeg verbose log 591 frames encoded (which matches the length/framerate). My concat.txt file has 60 jpegs, all exact same width and height. I searched the forums but couldn't really find anything similar. Can anybody clar
[20:47] <lameiro> ify?
[21:42] <c_14> lameiro: have you tried the image2 demuxer?
[21:42] <lameiro> c_14, no, i will read up and try it, thanks for the pointer
[22:06] <lameiro> c_14, got exactly same result ( http://pastebin.com/jm2GeLNB ) - thanks anyway
[22:08] <c_14> Are the first/last frames displaying correctly when you play the output?
[22:26] <lameiro> c_14, from visual inspection the first frame is playing too fast (not for 1sec) and maybe the last as well, but for the latter i can't be sure just visually. (is there any way to see interframe timing? i am using latest VLC as player)
[22:28] <lameiro> c_14,  all images are there for sure though
[22:30] <c_14> If you can get some sort of OSD up, you can check the timing against that.
[22:31] <c_14> Heck, you could timestamp with ffmpeg.
[22:31] <c_14> I just asked because I've had people here with issues where the first/last frame didn't display/only for a split-second.
[22:35] <lameiro> c_14, found in vlc how to do frame stepping, indeed first image is only displayed for 1 frame, while others stay for 10 frames as expected.
[22:35] <c_14> Can you switch from using -r 1 to -framerate 1 ?
[22:43] <c_14> Ok, so I went back through my logs. If your problem is the same as the one in my logs, you can fix it by outputting to matroska instead of mp4, or by using -vf fps=10 instead of -r 10 (though in that case the last frame might be cut short)
[22:44] <c_14> Though I'd try that with the -framerate 1 first just in case.
[22:51] <lameiro> with -framerate 1 (no change at output -r, should I?): http://pastebin.com/ukX6uSv1
[22:51] <lameiro> same result, first frame too short
[22:53] <c_14> Ok, that one was a longshot. But try outputting to mkv/using the fps filter.
[22:55] <lameiro> i will try those 2 things, thanks very much c_14
[23:41] <rjp421> do i need to specify a/v codecs again before appending another output using -f flv <rtmp_uri>?
[23:41] <c_14> yes, unless you use the tee muxer
[00:00] <vlatkozelka> Im trying to save a udp stream containing TV channels onto segments ... the recording is fine but , the timestamp is being reset so start is 00:00:00 , everything else is good . I tried -copyts but didnt work and made things worse , now it records like 30 1 second long ts files then  the rest the time i need but still timestamps are reset .
[00:00] --- Fri Aug 22 2014


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