[Ffmpeg-devel-irc] ffmpeg.log.20131105

[burek]

[00:01] <makar> would any of you recommend a simple command line tool to demux a ts, that is, to extract a single PID from a ts?
[00:06] <foucist> hey folks, i encoded some new f4v videos at 640x360, but when i don't have stretch on in jwplayer, it shows up considerably smaller.  you can see the ffmpeg -i for the new & old videos here: https://gist.github.com/foucist/137ba7f5ea796c0cad72
[00:07] <lvella> hey guys, do you know if I buy one of these, I'll be able to play blyrays in linux?
[00:07] <lvella> http://www.aliexpress.com/item/Special-price-free-shipping-USB-2-0-External-blu-ray-reader-BLU-RAY-Combo-BD-ROM/711790949.html
[00:08] <llogan> foucist: that's not our ffmpeg.
[00:08] <llogan> we don't serve their kind here
[00:16] <foucist> llogan: well, i'll try asking in #libav, but i'm just figurng that the issue is a lack of general encoding knowledge rather than differences between the two..  i.e. the fact that the old videos have "[PAR 1:1 DAR 16:9]"  where the new don't for example?  or something to do with framerate?
[00:18] <llogan> hard to say without your command or console output, but that's a moot point since you're not using ffmpeg
[07:55] <burek> :)
[07:56] <burek> i was replying to a post on the forum, and I was too lazy to type over and over again the same answer :)
[08:53] <tiksa> hi guys. I should do some video editing with ffmpeg and I'm asking if it's possible to make an ffmpeg one-liner with -filter_complex that includes video trimming, concatenating, overlay videos/images, text and so on? what do you think?
[08:53] <tiksa> is it realistic?
[09:06] <Ronald_Reagan> I've encoded a video with these settings: -c:v libx264 -preset slower -crf 14 -c:a copy video.mkv Adobe products cannot open this it seems. I would've thought they could. What sort of options would I use to make a file that I can open? Totally new to this video encoding stuff.
[09:12] <viric> tiksa: I want to do something similar. That's what mlt seems suited for...
[09:12] <viric> but it takes a lot of ram, and I couldn't find how to set the encoder parameters in it
[10:01] <tiksa> ok
[10:02] <tiksa> Next question.. How can I continue filter graph (?) after concat? I have something like "... concat=n=3:v=1:a=1 [a] [v] ' -map '[a]' -map '[v]'" Now I should add an overlay image, for example, to the output. Thanks for any help..
[10:03] <tiksa> I wasn't able to find anything from google so far
[10:46] <bouba> hi there, anyone's able to give me tips about this plz ?  http://pastebin.com/wmmDPD72 ; i just don't understand which param is not accepted by x264 (most probably in output)
[10:47] <bouba> the only thing which is not common is the INPUT file framerate flags
[12:37] <Baldino> Hi, is there any way to detect/select the forced subtitles of a subtitle stream in ffmpeg ?
[13:07] <sspiff>  I'm trying to figure out how the demuxing/decoding of dvb subtitles works, but I can't seem to figure it out.
[13:07] <sspiff> I'm looking at libavformat/mpegts.c, which is used for TS demuxing right?
[13:09] <bencoh> right
[13:09] <bencoh> have a look at libavcodec/dvbsubdec
[13:10] <JEEB> sspiff, if you want to talk internals of libavformat, I recommend switching to the -devel channel
[13:10] <JEEB> yeah, the libavcodec/dvbsubdec is the decoder
[13:10] <JEEB> libavformat/mpegts is the MPEG-TS demuxer
[13:11] <sspiff> JEEB: oops, wrong tab!
[13:11] <sspiff> bencoh, JEEB: thanks
[13:11] <dharriso> Hi, Im using hthe ffmpeg API to re-encode video over a network stream (HTTP). Is it possible to pad out AAC audio samples to a specific size?  Is it a case of appending hex 0 to samples or is there a construct for AAC like AVC Filler NAL to tell the player to ignore this data. I predict frame sizes up front for MP4 files to stream this content via HTTP
[13:11] <dharriso> thanks
[15:38] <dharriso> hi my connection dropped
[15:39] <dharriso> was there any answer to my question earlier in realtion to padding AAC frames to a specific size.  Is it possible?
[15:57] <dharriso> shold i try the ffmpeg-devel list
[16:15] <tiksa> dharriso: no, there wasn't any answer
[16:20] <dharriso> tiksa: have sent same question to mailing list, thanks
[18:10] <sspiff> Is there a way I can convince ffmpeg to preserve the original pts'es?
[18:18] <Mavrik> sspiff, probably with setpts filter?
[18:40] <sspiff> Mavrik: thanks
[20:46] <llogan> michaelni: more spam 3121 3122
[20:46] <llogan> that was meant for -devel...
[20:59] <maujhsn> Is this command correct: ffmpeg -f alsa -ac 2 -i pulse -f x11grab -r 30 -s 1024x768 -i :0.0 -c:a pcm_s16le -c:v libx264 -preset ultrafast -threads 0 ~/Desktop/music.mkv?
[21:01] <llogan> maujhsn: does the output look ok for you?
[21:02] <llogan> change -r to -framerate and -s to -video_size
[21:02] <llogan> (for x11grab)
[21:21] <renihs> ffmpeg stops recording audio when i select higher resolutions, e.g ffmpeg -f x11grab -r 30 -threads 6  -i :0.0 -f alsa -i hw:0,0 -acodec flac -vcodec libx264 bla.mkv  works fine
[21:21] <renihs> but once i add a resolution like -s 1680x1050 -> no audio captured, not sure if am doing something dumb or even right channel though :)
[21:22] <renihs> irc channel i mean :)
[21:25] <renihs> i only have "something distorted" for like 1/2 second on the beginning of the video
[21:32] <renihs> llogan, thanks
[21:32] <renihs> http://bpaste.net/show/147080/
[21:34] <llogan> renihs: does this help? ffmpeg -f x11grab -framerate 30 -video_size 1680x1050 -i :0.0 -f alsa -i hw:0,0 -acodec copy -vcodec libx264 -preset ultrafast -qp 0 bla.mkv
[21:36] <renihs> llogan, with your line, the "audio distortion" at th beginning is less stretched
[21:36] <renihs> and its definitive audio from what should be captured, just speed up and shortened to like 1/2s
[21:37] <renihs> http://bpaste.net/show/147083/  paste with sound
[21:37] <renihs> with lower resolution
[21:40] <llogan> renihs: using git master is preferred over (old) release branches
[21:41] <llogan> also see https://trac.ffmpeg.org/ticket/615
[21:41] <llogan> running two ffmpeg processes may help (one for audio, one for video). not really optimal solution though.
[21:43] <renihs> yup thats my case :)
[21:43] <renihs> hmmm
[21:43] <renihs> good idea
[21:45] <llogan> i wonder if arecord works normally when you're using ffmpeg to capture video (probably does, but i'm not sure)
[21:49] <renihs> i guess it does
[21:49] <renihs> i only set arecord -D front > receives stuff :p
[21:49] <renihs> when recording and playing audio
[21:49] <renihs> video recording
[21:50] <renihs> hmm well i guess i have to eithr reduce resolution or use 2 captures and merge them afterwards or like
[21:51] <llogan> if you choose to merge you can see if you can still increase framerate. screencasts look nice at higher frame rates (-framerate 60), IMO
[21:52] <llogan> and use the lossless example i gave you. then when you mux you can re-encode if you need to
[21:53] <renihs> actually, it libx264 related
[21:53] <renihs> if i capture for example with ffvhuff
[21:53] <renihs> it captures normally
[21:54] <llogan> i guess that's a solution then
[21:54] <renihs> will try with 60, problem is i am trying to capture sc2, diablo3 and stuff like that from wine to show off how greatly the csmt patches improve performance
[21:54] <renihs> not want to bump it too much :)
[21:55] <llogan> also experiment with huffyuv and ffv1. one of those might perform better than others.
[21:57] <renihs> llogan, thanks
[21:57] <renihs> i sadly know nothing about the codecs around atm
[21:57] <renihs> 60fps seem to be no problem though
[21:58] <llogan> using -r or -framerate?
[21:58] <renihs> grmbl, didnt build ffmpeg with vpx :p
[21:58] <renihs> -r
[21:58] <renihs> lemme read man
[21:59] <llogan> see https://trac.ffmpeg.org/ticket/3045
[21:59] <renihs> dont fine the -framerate option
[21:59] <renihs> s/fine/find/g
[22:00] <renihs> oh hmm
[22:00] <llogan> man ffmpeg-devices
[22:01] <renihs> oh hmm will be using -framerate
[22:02] <renihs> recompiling ffmpeg first :)
[22:02] <llogan> git master i hope
[22:02] <renihs> cant really view the raw video
[22:03] <llogan> with what player?
[22:03] <renihs> llogan, um, no i will do that in a seperate prefix
[22:03] <renihs> mplayer2, will need to rebuild that too ;p
[22:03] <renihs> among some other deps
[22:03] <renihs> i touch ffmpeg like a raw egg tbh :)
[22:04] <llogan> i thought people used mpv these days (i usually just use ffplay or mplayer)
[22:05] <renihs> oh, i guess i will fetch that :)
[22:05] <renihs> didnt even know about it
[22:06] <renihs> hmm fmpeg -threads 8 -y -i bla.mkv -c:a libvorbis -q:a 3 -c:v libvpx -b:v 2000k bla.webm
[22:06] <renihs> doesnt care about threads :p
[22:06] <renihs> pure single core getting beaten
[22:06] <renihs> ... poor
[22:06] <llogan> because you're appling threads to the input
[22:06] <renihs> omg :)
[22:06] <llogan> http://trac.ffmpeg.org/wiki/vpxEncodingGuide
[22:07] <renihs> so much fail :)
[22:07] <renihs> grmbl
[22:07] <llogan> but i know nothing of that encoder or how it deals with threads
[22:07] <renihs> in my defense i was chasing a "missing audio channel" for some time until i realised it doesnt get captured on that resolution
[22:07] <renihs> yeah i just like it because it will work in frickelfox and whatnot everwhere
[22:07] <llogan> it's a bug
[22:08] <renihs> well it performs slightly better now
[22:10] <renihs> grmbl, guess need todo more reading, now no sound anymore in output file
[22:10] <renihs> i have to admit, the builtin screen recorder in gnome3 was nifty :)
[22:58] <viric> I'm trying the mkvtoolnix Headers Editor (in mmg)... It only allows me to set the title
[22:58] <viric> While here I see dozens of more tags: http://wiki.webmproject.org/webm-metadata/global-metadata
[22:58] <viric> How is it?
[23:14] <sacarasc> viric: This channel isn't affiliated with mkvtoolnix. But you can use ffmpeg to add meta data.
[23:14] <viric> right, but that requires remuxing.
[23:15] <viric> I asked here, because maybe there are some restrictions on metadata tags that I don't know (but mmg knows :)
[23:15] <viric> and maybe someone knows too.
[23:25] <CarlosTrading1> hi
[23:26] <CarlosTrading1> i am having this error Codec AVOption g (set the group of picture (GOP) size) specified for input file #0 (http://xxxxxxxxxxxxxxxx:xxxx/) is not a decoding option.
[23:26] <CarlosTrading1> does anyone know ?
[23:30] <ac_slater> Hey guys is there a simple way to retrieve the encoded bitrate of a file? I know that sounds weird but I have some video files and I'm curious what settings the person used to encode then with x264. Maybe I should ask elsewhere
[23:32] <sacarasc> Use the programme MediaInfo, it will tell you all the options used by x264 to encode the file.
[23:34] <ac_slater> sacarasc: what about one for linux?
[23:34] <ac_slater> oh nevermind
[23:34] <ac_slater> it's available for linux too
[23:34] Action: sacarasc nods.
[23:35] <ac_slater> ;) thanks
[23:55] <llogan> CarlosTrading1: how do you get the error?
[23:56] <llogan> ac_slater: you don't need mediainfo. "strings input.mp4 | grep x264"
[00:00] --- Wed Nov  6 2013