[Ffmpeg-devel-irc] ffmpeg.log.20160501

Mon May 2 02:05:01 CEST 2016

[00:26:52 CEST] <dctrmnhttn> hello everyone
[01:15:53 CEST] <hyponic> anyone here?
[01:15:58 CEST] <sfan5> no
[02:42:26 CEST] <hyponic> i am trying to transcode a stream and burn subtites from that stream. i just have no idea how to get it done. i have been googling for days without bein able to crack it. here is the stream: http://pastebin.com/JnpPYTx2
[02:43:21 CEST] <c_14> Don't post questions in both channels at the same time and especially don't post user-questions in #ffmpeg-devel
[02:43:45 CEST] <c_14> Also, if by "stream" you mean live stream then you're currently out of luck
[02:44:06 CEST] <DHE> 3 channels is the record for me...
[02:44:26 CEST] <c_14> ffmpeg currently doesn't support burning in subtitles from streams (mainly due to the fact of how libavfilter handles subtitles (it doesn't)
[02:45:14 CEST] <c_14> )
[02:47:25 CEST] <hyponic> c_14 sorry about that... what would be the workaround? if there is any
[02:48:22 CEST] <c_14> you could start 2 ffmpeg processes reading from that stream and have one of them output the subtitles to a named pipe. Then the other process will read the stream and open the named pipe with the subtitles filter
[02:48:26 CEST] <c_14> that should potentially work
[02:49:50 CEST] <c_14> you could probably even just have the first process dump to an mkv fifo and then have the second read from that and use it in the subtitles filter
[02:49:55 CEST] <c_14> That way you don't have to open the stream twice
[02:52:41 CEST] <hyponic> c_14 i am not sure how to get something like that done. could you please explain?
[02:53:35 CEST] <c_14> mkfifo foo.mkv; ffmpeg -i http://foo -c copy -f matroska foo.mkv& ffmpeg -i foo.mkv -vf subtitles=foo.mkv out.mkv
[02:53:38 CEST] <c_14> should do it
[02:54:07 CEST] <hyponic> c_14 alternatively what i am trying to do is to do this: http://pastebin.com/HKE6TxkS but it seems that ffmpeg's  m3u8 muxer removes the index teletext page.
[02:57:44 CEST] Action: c_14 has no clue about teletext or how ffmpeg handles it
[03:01:43 CEST] <hyponic> c_14 how about something like this.. would that make it easier? http://pastebin.com/XHJXabbb
[03:02:28 CEST] <c_14> Make what easier?
[03:04:13 CEST] <hyponic> solve my problem.. pass this through ffmpeg's m3u8 muxer
[03:04:29 CEST] <hyponic> or burn it on the video
[03:07:43 CEST] <c_14> I'm not sure ffmpeg's hls muxer can handle multiple subtitle streams
[03:08:26 CEST] <c_14> you'd have to pick one to keep and throw the others away
[03:10:11 CEST] <hyponic> c_14 how would i pick one?
[03:10:44 CEST] <c_14> make the -map more specific. I.e. -map 0:s:0 instead of -map 0:s to pick the first one
[03:11:01 CEST] <c_14> You can also pick by metadata etc
[03:11:19 CEST] <c_14> look in the manpage for examples/info
[03:12:05 CEST] <hyponic> c_14 i'd rather transcode the sub on the video if that is doable
[03:13:16 CEST] <c_14> 00:53 <c_14> mkfifo foo.mkv; ffmpeg -i http://foo -c copy -f matroska foo.mkv& ffmpeg -i foo.mkv -vf subtitles=foo.mkv out.mkv
[03:13:20 CEST] <hyponic> c_14 0:s:2 would that be: Stream #0:6(fra): Subtitle: subrip (default) or does it have to be 0:s:6
[03:13:36 CEST] <c_14> Just change out.mkv to out.m3u8 add the hls options, drop the -map 0:s and add -sn
[03:13:57 CEST] <c_14> 0:s:2 would be the fra stream, yes
[03:14:10 CEST] <c_14> you can also do 0:6 to get the 7th stream (which would also be the fra one)
[03:14:15 CEST] <c_14> *the fra subtitle one
[03:18:14 CEST] <hyponic> c_14 sub2video: non-bitmap subtitlee=
[03:19:46 CEST] <c_14> hmm?
[03:25:13 CEST] <hyponic> c_14 tried another aproach: http://pastebin.com/3Yp2jTdi
[03:25:21 CEST] <hyponic> a different error
[04:38:05 CEST] <ptomblin> Hi. Im trying to make a green screen background that I can overlay stuff on using Garmin VIRB Edit, using the command `ffmpeg -f lavfi -i color=color=green -s 1920x1080 -t 3600 -r 60 small_green.mp4` but VIRB Edit sees the result as 1440x1080 instead of 1920x1080. Why is that?
[04:39:16 CEST] <ptomblin> ffprobe results in http://pastebin.com/bLCUumRx
[09:23:36 CEST] <Fyr> guys, how to create something like this:
[09:23:36 CEST] <Fyr> https://vimeo.com/85590386
[09:23:36 CEST] <Fyr> ?
[09:23:59 CEST] <Fyr> what soft was used to create this video?
[09:28:38 CEST] <Betablocker> Fyr:  css3 / javascript
[09:28:47 CEST] <Fyr> %)
[09:28:51 CEST] <Fyr> impossible
[09:30:02 CEST] <Betablocker> why ?
[09:30:14 CEST] <Betablocker> looks like a css3 animation to me
[09:51:14 CEST] <A124> Hello, probably on the net, but cannot find. Can someone sum diffrence between yadif 1 and 3?
[09:56:19 CEST] <A124> Quote: And that's where diff is left, if using yadif in mode 2 or 3. But in modes 0 and 1, more is done to the interpolated frame...
[09:56:22 CEST] <A124> Quote: And that's all modes 2 and 3 add on top of modes 0 and 1.
[09:56:37 CEST] <A124> Unless I do not understand English those two are conflicting.
[09:57:56 CEST] <A124> 3 : double frame rate, skips spatial interlacing check.
[09:58:12 CEST] <A124> I think that gets me answer (froma visynth port amusingly)
[09:59:29 CEST] <durandal_1707> Is hard to read docs
[10:03:10 CEST] <A124> I did not find the right docs apparently.
[10:03:50 CEST] <A124> Still it seems that filters with avisynth win at deinterlacing. Makes me sad to see it is made for win only.
[10:52:48 CEST] <operator> trying to stream a video file to youtube, but getting error. http://pastebin.com/UeeGn5ZH
[10:53:34 CEST] <operator> the problem is video codec, do I understand it right?
[12:34:58 CEST] <DHE> Is there any examples or means of using the downmix information from available sources to control the downmix process? using libswresample to convert 5.1 to stereo audio but the center channel needs to be turned up a bit
[12:39:03 CEST] <debianuser> Hello. What's a good way to silence several audio fragments of the file? `ffmpeg -i input.mkv -c copy -acodec flac -af "volume='if(between(t,10,11),0,1)':eval=frame, volume='if(between(t,12,13),0,1)':eval=frame" output.mkv` kind of works but I thought maybe there's an easier way to do that?
[12:39:32 CEST] <debianuser> DHE: Maybe this can help?: https://trac.ffmpeg.org/wiki/AudioChannelManipulation
[12:40:53 CEST] <DHE> debianuser: looking at the source code I saw that the AC3 codec provides side data which includes downmix info, like the orginal audio source suggests a downsampling matrix. but libswresample doesn't seem to offer anything to read it or fill in the matrix myself without sticking my hands into "internal" fields
[12:46:22 CEST] <DHE> also, API not CLI
[12:46:55 CEST] <debianuser> ah! I don't know then, sorry. :(
[12:47:41 CEST] <c_14> DHE: there's an option eh
[12:48:02 CEST] <c_14> DHE: the drc_scale option on the ac3 decoder maybe
[12:48:31 CEST] <c_14> wait, no
[12:48:35 CEST] <c_14> That wasn't it
[12:49:10 CEST] <DHE> I'm trying to see if there is a way to make AC3 output in stereo directly. It looks like it from the code - that it will use the matrix for itself - but having trouble doing it. So I'm checking both directions
[12:49:10 CEST] <c_14> I know it's possible (mpv does it). I'm just not quite sure how
[12:53:13 CEST] <c_14> DHE: it looks like you just have to set the request_channel_layout on the avctx
[12:53:33 CEST] <c_14> +to a valid AV_CH_LAYOUT
[13:00:52 CEST] <c_14> debianuser: you could use -af volume='if(between(t,10,11)+between(t,12,13),0,1):eval=frame'
[13:01:10 CEST] <c_14> other than that, probably no
[13:08:36 CEST] <debianuser> c_14: Ah, ok, thank you!
[13:12:28 CEST] <DHE> c_14: I think that worked...
[13:12:38 CEST] <DHE> (request_channel_layout)
[15:43:54 CEST] <MrSassyPants> ok how do I enable scene cut key frames in vp9 ?
[16:36:23 CEST] <hyponic> anyone that can help me out with a teletext subtitle burning issue?
[16:59:17 CEST] <getoo> i am trying to slice a video , used some google searches but wont help .. its in the middle of the video starts at 19:40 and its 5 minutes long
[17:07:03 CEST] <c_14> ffmpeg -ss 19:40 -i video -t 5:00 out.mkv
[17:15:12 CEST] <getoo> c_14: thank you
[17:27:02 CEST] <elichai2> hey
[17:27:16 CEST] <elichai2> why Ubuntu repo ffmpeg version is only 2.8.6?
[17:28:47 CEST] <c_14> Ask the package maintainer
[17:29:10 CEST] <furq> what a nice young man
[17:31:38 CEST] <elichai2> is there an easy way to upgrade to 3.x?
[17:31:52 CEST] <c_14> download a static build
[17:31:53 CEST] <furq> elichai2: http://johnvansickle.com/ffmpeg/
[17:32:45 CEST] <elichai2> furq, yeah, but where should i put the binaries and manpages?
[17:35:02 CEST] <furq> /usr/local
[18:11:10 CEST] <getoo> how do i rip the audio from a .mkv .. i believe the audio encoding is vorbis
[18:11:37 CEST] <furq> -i src.mkv -c copy -map 0:a out.ogg
[18:11:50 CEST] <getoo> furq: thank you
[18:13:49 CEST] <getoo> that was almost instant :)
[20:17:05 CEST] <needALamp> i had video that i download from the internet, it has a subtitle that encode in the container ( checked by ffmpeg), but when i play it, it didn't shown up??? what is going on, thank you.
[20:20:26 CEST] <needALamp> hello guys..
[20:26:05 CEST] <c_14> What video player?
[20:49:42 CEST] <needALamp> hello
[20:49:55 CEST] <needALamp> hello c_14 its vlc
[20:51:25 CEST] <needALamp> but i also tested to upload this file to youtube but didnt work too
[20:51:48 CEST] <c_14> Can you upload the output of ffprobe of that file to a pastebin service?
[20:54:35 CEST] <needALamp_> hello c_14 sorry got bust out.
[20:54:54 CEST] <c_14> Can you upload the output of ffprobe of that file to a pastebin service?
[20:55:31 CEST] <needALamp_> a moment
[20:59:28 CEST] <Anonaly> hi ppl, how do I see what my ffmpeg version is ?
[21:00:09 CEST] <c_14> ffmpeg -version
[21:37:33 CEST] <anomie__> How can I render subtitles over a still image? Everything I try, only the first subtitle gets burned into the image then that's used for the rest of the video.
[21:50:59 CEST] <durandal_170> anomie__: you need to loop image
[21:51:42 CEST] <anomie__> Okay.
[21:53:01 CEST] <anomie__> I think that's working. Thanks.
[22:40:30 CEST] <hyponic> anyone with teletext subtitle experience? i am unable to burn teletext subtiles from a ts stream. any help i greatly appriciated.
[23:05:53 CEST] <Illya> how can I extract a specific audio frame of an MPEG-1 layer-3 stream?
[23:09:08 CEST] <JEEB> you'd have to use the API for that, so I recommend a tool that specifically outputs information on MPEG-1 Layer 3 streams
[23:25:12 CEST] <Anonaly> hey ppl I am about to convert hundreds of videos on my computer from .FLV (h264, ac3) to mp4, because my TV does not play  .flv files and serviio does not transcode them
[23:25:23 CEST] <Anonaly> http://forum.serviio.org/viewtopic.php?f=5&t=21979
[23:25:29 CEST] <Anonaly> going to use avconv like this
[23:25:38 CEST] <Anonaly> avconv -i infile.flv outfile.mp4,
[23:26:05 CEST] <durandal_170> this is ffmpeg channel not avconv
[23:32:48 CEST] <furq> Anonaly: add -c copy
[23:40:11 CEST] <Anonaly> codec copy furq what is this for ?
[23:41:32 CEST] <furq> you're converting flv to mp4, you don't need to reencode
[23:42:01 CEST] <furq> unless your tv doesn't play h.264 in which case your initial command wouldn't work anyway, and also you should throw your tv in the bin
[23:48:28 CEST] <Anonaly> furq, it was a free tv, 55 inch with 3d bla bla.
[23:48:49 CEST] <Anonaly> I would end up getting another tv that doesn't play some other type of file anyway
[23:49:08 CEST] <Anonaly> because so far no tv's I have experimented with play all files
[23:49:14 CEST] <Anonaly> AVI files = garbage,
[23:49:21 CEST] <Anonaly> FLV files = garbage
[23:50:12 CEST] <Anonaly> I actually blew up a Toshiba tv at london drugs once because the sales rep told me my Toshiba laptop can plug into the TV with a VGA cord, so he took my laptop plugged it in to VGA
[23:50:21 CEST] <Anonaly> and my toshiba laptop fried his toshiba tv
[23:50:26 CEST] <Anonaly> infront of our eyes
[23:50:32 CEST] <Anonaly> vga cord
[23:51:02 CEST] <Anonaly> (and it was his fault because he plugged it in)
[00:00:00 CEST] --- Mon May  2 2016