[Ffmpeg-devel-irc] ffmpeg.log.20151103

[burek]

[00:04:57 CET] <debianuser> c_14: `-disposition:a:1 original` seems working at least for my file! Thank you!
[00:40:35 CET] <Primer> Hi, I've been trying to compile OBS, which depends on ffmpeg libraries. The instructions state that this PPA should suffice: ppa:kirillshkrogalev/ffmpeg-next. Thing is, the build process complains that swresample is missing, and I can find no package that provides that. I'm hoping someone here is familiar with that PPA and can help. Thanks.
[00:41:14 CET] <c_14> ffmpeg provides libswresample
[00:41:40 CET] <c_14> (if proberly built)
[00:41:43 CET] <c_14> *properly
[00:42:55 CET] <Primer> I figure as much. There were other requirements that weren't met, and I found those as packages. For example, libswscale-dev was also needed, and there was a package
[00:43:44 CET] <Primer> But there is no libswresample-dev package, as suggested by this post: https://obsproject.com/forum/threads/ffmpeg-version-questions.20725/
[00:46:26 CET] <c_14> >libswresample-ffmpeg-dev
[00:46:29 CET] <c_14> According to https://launchpad.net/~kirillshkrogalev/+archive/ubuntu/ffmpeg-next/+sourcepub/4572790/+listing-archive-extra
[00:46:39 CET] <Primer> yeah, well...
[00:46:57 CET] <Primer>  libswresample-ffmpeg-dev : Depends: libavutil-ffmpeg-dev (= 7:2.4.3-1ubuntu1~trusty6) but it is not going to be installed
[00:47:24 CET] <c_14> And why isn't it going to be installed? Does it say anything else?
[00:48:17 CET] <Primer> It's a circular dep. Installing libavutil-ffmpeg-dev removes all the other ffmpeg dev packages from the PPA
[00:48:42 CET] <c_14> Looks like you have some sort of packaging conflict going on.
[00:48:47 CET] <c_14> You can always install ffmpeg from source.
[00:48:54 CET] <c_14> *build
[00:49:28 CET] <Primer> yeah, I did that too
[00:49:39 CET] <c_14> What was the problem with that?
[00:49:59 CET] <Primer> The package built, but when it installs....
[00:50:24 CET] <Primer>  trying to overwrite '/usr/include/libavformat/avio.h', which is also in package libavformat-dev 6:9.18-0ubuntu0.14.04.1
[00:50:34 CET] <Primer> So I remove the package that owns that, and...
[00:50:58 CET] <c_14> It might just be easier to set the prefix to /usr/local
[00:52:12 CET] <Primer>  qt-faststart (7:2.4.3-1ubuntu1~trusty6) breaks ffmpeg (<< 7:2) and is installed.
[00:53:11 CET] <Primer> So I disregard that and compile OBS
[00:53:23 CET] <Primer> make[2]: *** No rule to make target `/usr/lib/x86_64-linux-gnu/libavcodec.so', needed by `libobs/libobs.so.0'.  Stop.
[00:54:30 CET] <Primer> Ok, I suppose I should tweak the configuration parameters to show where the libraries actually are
[00:55:27 CET] <Primer> heh, yeah, I hadn't rerun configure, my bad
[00:55:31 CET] <Primer> it's working now
[00:55:35 CET] <furq> Primer: https://launchpad.net/~mc3man/+archive/ubuntu/trusty-media/+packages
[00:55:40 CET] <furq> that's the PPA recommended on ffmpeg.org
[00:56:32 CET] <Primer> furq: lovely, I'll try that next
[01:53:47 CET] <Primer> ok, I got everything I needed working. Thanks for the help
[02:34:19 CET] <iksik> hello
[02:35:03 CET] <iksik> is it somehow possible to stream video and audio but both to separate receivers?
[02:36:41 CET] <llogan> ffmpeg -i input -map 0:v output0 -map 0:a output1
[02:38:00 CET] <iksik> llogan: thank You
[02:54:31 CET] <Matador> My only issue is this Decklink input buffer overrun
[09:37:45 CET] <leogsa> Hello to everybody
[09:38:38 CET] <leogsa> what is the right way to automatically insert date-time in the output filename?
[09:42:06 CET] <waressearcher2> leogsa: file_name_$(date | sed -e "s/ /_/g")_.avi ?
[09:45:32 CET] <leogsa> waressearcher2: no. it writes that "sed" is not a program or file
[09:46:04 CET] <leogsa> ffmpeg -i rtmp://172.22.45.38:1935/live/stream4 -vcodec copy -b 64k -acodec mp3 file_name_$(date | sed -e "s/ /_/g")_.mkv
[09:47:41 CET] <leogsa> I do it in windows. does it matter for your command where to run it?
[09:55:02 CET] <leogsa> waressearcher2: but in linux it works.thanx
[10:43:20 CET] <Rippd> Is it possible to stream a video from ffmpeg to vlc player?
[10:55:21 CET] <leogsa> Rippd: no. you will need any streaming server. with ffmpeg you make rtmp out of rtsp. And then send this rtmp to streaming server. and then you may watch your stream from streaming server with vlc
[10:55:55 CET] <Rippd> A bit different wuestion: Is ist possible to pause ffmpeg while it is streaming?
[10:56:22 CET] <leogsa> Rippd: sorry. (FILE instead of RTSP) no. you will need any streaming server. with ffmpeg you make rtmp out of your file. And then send this rtmp to streaming server. and then you may watch your stream from streaming server with vlc
[10:57:00 CET] <Rippd> leogsa, is it possible to tell ffmpeg to pause this rtmp stream?
[10:57:24 CET] <Rippd> i don't think so because it doesn't accept comamnds while actually working, correct?
[10:57:46 CET] <relaxed> Rippd: ctrl z (if you're using a unix like OS)
[10:58:04 CET] <leogsa> Rippd: I'm not shure. I guess the answer is no.
[10:58:28 CET] <relaxed> then `fg` to bring it to foreground
[10:58:36 CET] <leogsa> Rippd: you may stop your command. but pause?
[10:58:50 CET] <BAWSTi> Hi, I'm currently trying to get ffmpeg to work in my android application. If I want to use the command "ffmpeg -i input.wav -f mp2 output.mp3" can I do something like "ffmpeg -i /Download/input.wav -f mp2 /Download/output.mp3"??
[10:58:58 CET] <Rippd> So i would need to tell the streming server to buffer everything?
[11:39:56 CET] <Ulrar> Hi, I compiled a ffmpeg by hand for a client, and it works fine but he'd like to have alpha supports in drawtext. How do I enable that ? It does support drawtext currently, but apparently not alpha settings (if I understood what he said :D)
[11:53:13 CET] <Mordae> Hi!
[11:53:43 CET] <Mordae> Is it possible to "catch up" to a stream with ffmpeg?
[11:56:21 CET] <Mordae> I mean, there is a hardware encoder on the network that produces h264 stream at 30 fps with an I-frame every second.
[11:58:48 CET] <Mordae> It seems that the client ffmpeg will process the stream (relative to other inputs) with a random delay.
[12:02:07 CET] <BtbN> There will allways be a delay in streaming
[12:02:13 CET] <BtbN> as long as it's just a few seconds, you're fine.
[12:03:26 CET] <Mordae> What I mean is that the delay is not consistent across runs.
[12:03:56 CET] <BtbN> yes, there's stuff flowing through a network, and the time it takes for the next I-Frame to arrive depends on where you start.
[12:04:06 CET] <BtbN> It will never be 100% consistent
[12:07:02 CET] <Mordae> I would like to discard everything until all streams are live (have received their first I-frame) and then start outputting. Would that be possible?
[12:07:48 CET] <Mordae> (well, not discard; proceed with decoding, but not encode)
[12:11:31 CET] <BtbN> That's what's happening. Without an I frame, ffmpeg can't decode the stream and discards it.
[12:12:17 CET] <BtbN> If you need real-time low latency streaming, you'll have to roll your own player/transcoder. ffmpeg is designed for reliability, not ultra-low-latency.
[12:15:52 CET] <Mordae> Well, it discards the leading portion of that particular stream, but when I am combining multiple streams, each will appear to be delayed by some amount (depending on the other frame's I-frame arrival).
[12:16:05 CET] <Mordae> This is not about streaming, but about recording.
[12:58:10 CET] <DHE> if you're using libx264 you might try "-preset:v zerolatency" to see if it helps any
[12:58:32 CET] <DHE> hurts image quality/output bitrate
[13:53:19 CET] <Mordae> DHE: I can't. Encoder is a davinci box I cannot really modify.
[13:55:12 CET] <Mordae> Frankly, I am now thinking about decoding all the streams to something without I-frames. For example to huffyuv. Then I would be able to subscribe to all these streams and re-encode on the same time base.
[13:55:49 CET] <Mordae> The only problem is that I have no idea how to stream huffyuv over udp.
[13:56:33 CET] <c_14> ffmpeg -i something -c:v huffyuv -f mpegts udp://localhost:5555
[13:58:41 CET] <bencoh> ffmpeg can mux huffyuv in mpegts?
[14:00:17 CET] <Mordae> Nope.
[14:00:54 CET] <Mordae> And won't stream mkv.
[14:01:04 CET] <c_14> Worked for me.
[14:02:04 CET] <Mordae> c_14: Try receiving.
[14:03:33 CET] <c_14> Hmm, you're right.
[14:15:44 CET] <Admin__> hey, anyone ever see ffmpeg segmenting run away with a segment size ?
[14:16:28 CET] <Admin__> most segments run for hours at 2 - 3 M / file but after some time all channels ( streams ) go to large sizes like 100+MB each file on a .ts and it doens't rotate but it happens on all channels not just one
[14:16:30 CET] <Admin__> very very odd
[14:16:34 CET] <Admin__> a bug maybe?
[14:53:57 CET] <DHE> Admin__: I've seen that happen, usually when there's a stream problem. I've also had them go days/weeks without issue
[14:54:47 CET] <Admin__> hum... i get stream problem but.. if it goes down it should stop writing and then it should continue
[14:54:52 CET] <Admin__> or at least write ( blank ) data
[16:08:17 CET] <mdsh> when encoding audio but copying video, the -map commands appear to be ignored and the audio stream ends up as stream 0 - am I doing something wrong or is this a know limitation with the current git head?
[16:08:43 CET] <c_14> There is no way to ensure ordering of output streams (nor does it really matter).
[16:09:51 CET] <mdsh> I disagree with your assertion that is does not matter
[16:10:54 CET] <c_14> Why does it matter?
[16:12:14 CET] <Fjorgynn> apt-get install vim
[16:12:27 CET] <mdsh> compatibility with specifications provided by third parties - contractual oblications
[16:14:21 CET] <c_14> What's your current command.
[16:19:02 CET] <mdsh> ffmpeg -loglevel debug -threads 4 -c:a pcm_s24le -i pipe: -threads 4 -c:v copy -aspect:v 16:9 -map 0:v -threads 4 -c:a:0 pcm_s24le -ac:0 4 -map 0:a -threads 4 -filter_complex "[0:1][0:2][0:3][0:4]amerge=inputs=4,pan=4c|c0=0.5*c0+0.5*c1|c1=0.5*c0+0.5*c1|c2=0.5*c2+0.5*c3|c3=0.5*c2+0.5*c3" -f nut pipe:
[16:21:12 CET] <c_14> Try adding an explicit map to the filter_complex, and then placing all the maps after the filter_complex in the order you want them
[16:21:33 CET] <c_14> Although
[16:21:39 CET] <c_14> Is the output from the filter_complex even used?
[16:23:47 CET] <mdsh> I get out the mixed audio from the filter_complex (I believe - embarrassing if I'm wrong) - at least FFmpeg tells me that it is "pan -> Stream #0:0 (pcm_s24le)"
[16:24:30 CET] <c_14> Ok, then that's probably the reason. Add an explicit output pad to the end of the filterchain and map it explicitly.
[16:26:17 CET] <mdsh> I think I tried that, maybe I got the format wrong - let me try again...
[16:29:09 CET] <mdsh> thank's c_14 - I got the format wrong for the output pad -> -map command. Working perfectly now. Thanks for your help
[18:08:07 CET] <spoiled1234> when concat three avi videos, I am using the codec mpeg.  After I receive the final version of the video, there is a black frame between each video segment.  Just wondering if anyone has experienced this before?
[20:01:40 CET] <Youbi> Hi, I just built ffmpeg and mpv, and there is no subrip support with ffmpeg. How can I enable it?
[20:14:41 CET] <c_14> Youbi: what exactly is the issue?
[20:17:41 CET] <Youbi> c_14, when I run `mpv my_movie.mkv`, and there is a my_movie.srt file, mpv start but there is a warning message:
[20:18:00 CET] <Youbi> [sub] Could not find subtitle decoder for format 'subrip'.
[20:18:31 CET] <c_14> I don't think it's possible _not_ to build the subrip decoder. (unless you're doing weird things)
[20:18:39 CET] <c_14> Does ffmpeg -codecs list suprib?
[20:18:43 CET] <c_14> *subrip
[20:19:11 CET] <Youbi> DES... subrip               SubRip subtitle (decoders: srt subrip ) (encoders: srt subrip )
[20:19:34 CET] <c_14> ffmpeg -i file -f null /dev/null <- does that show any warnings or errors?
[20:21:34 CET] <Youbi> Nope
[20:21:45 CET] <c_14> Ask in #mpv
[20:21:47 CET] <Youbi> Should it show anything about srt file?
[20:21:52 CET] <c_14> Oh
[20:21:55 CET] <c_14> Is the srt file separate?
[20:22:16 CET] <c_14> If it is, specify the srt file instead of the video in that above command
[20:23:17 CET] <Youbi> Yes it is.
[20:23:34 CET] <waressearcher2> hallo leute
[20:23:43 CET] <Youbi> Input #0, srt, from '/home/olimex/media/Dr.Who Seasons 1-7/Doctor Who 2012 - Season 7/S07E01 Asylum Of The Daleks 720p.srt':
[20:23:46 CET] <Youbi>   Duration: N/A, bitrate: N/A
[20:23:48 CET] <Youbi>     Stream #0:0: Subtitle: subrip
[20:23:58 CET] <Youbi> (error on output stream because its /dev/null)
[20:24:37 CET] <c_14> It shouldn't error out on that case though.
[20:26:32 CET] <Youbi> Output #0, null, to '/dev/null':
[20:26:35 CET] <Youbi> Output file #0 does not contain any stream
[20:26:42 CET] <Youbi> c_14: You mean that ^ is not normal?
[20:26:58 CET] <c_14> Ah, change the -f null to -f srt
[20:35:06 CET] <Youbi> https://dpaste.de/jM8v/raw I get this
[20:37:57 CET] <c_14> Looks fine to me.
[20:40:08 CET] <c_14> Probably an mpv issue then.
[20:42:30 CET] <Youbi> Ok, Im chatting on #mpv atm ^^
[20:42:34 CET] <Youbi> Thanks for your help :)
[20:46:18 CET] <ChocolateArmpits> How can I set the start time of an mpegts file when remuxing ?
[20:47:34 CET] <c_14> No good way I know of.
[20:49:20 CET] <ChocolateArmpits> Well the segmenter has an option for that, isn't that implemented somehow else for single files ?
[20:49:57 CET] <c_14> Well, there's -start_at_zero
[20:50:07 CET] <c_14> Which does something similar.
[20:50:09 CET] <c_14> But besides that.
[20:50:45 CET] <ChocolateArmpits> the segmenter has "-initial_offset"
[20:50:57 CET] <ChocolateArmpits> That's what I had in mind at least
[20:53:22 CET] <klaxa> what about setpts filter?
[20:53:42 CET] <c_14> Ah, that should do it, more or less.
[20:53:42 CET] <klaxa> and something like setpts=STARTPTS-PTS or so
[20:53:43 CET] <Youbi> c_14: Should it be a missing libass/?
[20:54:12 CET] <c_14> If you don't have libass, mpv won't be able to render text subtitles. Yes. (Though the error message is a bit weird).
[20:54:35 CET] <klaxa> ah, it should be the other way around i think, PTS-STARTPTS
[20:54:39 CET] <ChocolateArmpits> klaxa: using filters means conversion
[20:54:40 CET] <klaxa> that way it starts at 0
[20:54:45 CET] <klaxa> it does
[20:55:09 CET] <c_14> Well, it would be PTS-STARTPTS+[START_TIMESTAMP]
[20:55:09 CET] <klaxa> ah, you said remuxing, sorry
[20:59:33 CET] <Youbi> Yes, its weird that libass is needed to render any subtitle format ^^'
[21:06:48 CET] <ChocolateArmpits> Another question, how does an inter frame in H264 exactly determine where to look for a reference frame. Is it a frame offset setting or something ?
[21:10:49 CET] <BtbN> it has a list of reference frames.
[21:12:24 CET] <ChocolateArmpits> BtbN: is the list made up of offsets, say P frame is +5 frames.
[21:12:29 CET] <ChocolateArmpits> ?
[21:12:56 CET] <BtbN> No idea, you'll have to read the h264 spec for implementation details.
[21:59:11 CET] <Guest39> what does error code -22 mean?
[22:02:03 CET] <llogan> possibly a messed up build
[22:03:52 CET] <Guest39> Its the return from avcodec_decode_video2(gVideoCodecCtx, gFrame, &frameFinished, packet);
[22:06:58 CET] <ChocolateArmpits> BtbN:  yeah it seems to be a reference list (two of them in fact) giving an offset
[22:07:41 CET] <llogan> Guest39: i don't know. try libav-user mailing list.
[22:08:03 CET] <Guest39> ok thanks
[22:58:37 CET] <waressearcher2> wie gehts
[22:58:44 CET] <waressearcher2> wie stehts
[22:59:52 CET] <user3> I have several .mp4 video files (them all with audio), some with video motion and others with only a fixed background throughout. is there a test I can apply to determine if a given mp4 file has only a fixed background
[23:00:39 CET] <user3>  it's ok if the test has to read the whole file
[23:19:46 CET] <ubuntu-mate> Probably not THE answer, but have you given ffprobe a try?
[23:43:55 CET] <user3> I will. I have to reboot before
[00:00:00 CET] --- Wed Nov  4 2015