[Ffmpeg-devel-irc] ffmpeg.log.20120611

[burek]

[02:13] <hwk> does ffmpeg support gpu encoding?
[02:14] <sacarasc> No.
[02:14] <hwk> is there any encoder that uses the gpu?
[02:14] <sacarasc> I've heard that encoding isn't a job suited for GPUs.
[02:15] <hwk> http://www.mainconcept.com/products/sdks/gpu-acceleration/cuda-h264avc.html
[02:15] <hwk> i found this
[02:15] <sacarasc> That's decoding, no?
[02:15] <hwk> CUDA H.264/AVC Encoder SDK 1.1
[02:16] <sacarasc> Well, you have that, then. :p
[02:16] <hwk> :)
[02:16] <sacarasc> On Windows with Nvidia.
[02:16] <hwk> http://www.mainconcept.com/fileadmin/user_upload/download/product_sheets/CUDA-Sheets_06-2010.pdf
[02:17] <hwk> seems very fast comparing to cpu
[02:19] <hwk> yep, nothing on linux
[02:20] <hwk> and its missing some features
[02:22] <hwk> not gonna get a windows dedicated server
[06:24] <namit_> hello.. I am having problems configuring ffmpeg .... it says ERROR: libfaac not found
[06:24] <namit_> if anybody could help on the matter..
[06:25] <namit_> I used the command configure --enable-gpl --enable-nonfree --enable-pthreads --enable-libfaac --enable-libmp3lame --enable-libx264
[06:27] <relaxed> namit_: install libfaac-dev and try again
[06:28] <relaxed> or libvo-aacenc
[06:29] <namit_> I cloned it from the github ... the ffmpeg... and used the command..
[06:30] <relaxed> that tells me nothing
[06:30] <relaxed> which distro are you using?
[06:31] <namit_> the recommended one... I installed the libfaac-dev
[06:31] <namit_> now the error changed to ERROR: libmp3lame >= 3.98.3
[06:31] <namit_> not ffound
[06:32] <relaxed> install the dev packages for all externals libs you want support for
[06:32] <namit_> okies
[06:32] <namit_> thanks
[06:33] <relaxed> also, "the recommended one" tells me nothing.
[06:33] <namit_> sorry...
[06:34] <relaxed> This game is pretty easy. You want help; so I ask questions and require spific answers in order to help you.
[06:34] <relaxed> specific*
[06:35] <namit_> I was able to install it ... thanks :)
[07:53] <dan_> hi
[07:53] <dan_> can anyone help me figure out how to read pts value from a pes?
[07:59] <dan_> (or could suggest a better channel to try)
[08:07] <dan_> found some parts of mpeg.c / mpegts.c which seems to do it, but the code is pretty inscrutable
[08:22] <grepper> dan_: just wrong time rather than wrong channel
[08:23] <dan_> o :/
[08:24] <grepper> between 7 hrs to 20 hrs from now is probably better time to ask, looking at activity in my scrollback
[08:25] <dan_> ok
[08:25] <dan_> thanks
[09:23] <shroomM> hey, how do I install ffmpeg man page?
[10:09] <Binbo> How ffmpeg know which packet is belong to which frame?
[11:03] <zap0> what?
[11:44] <Wakou> Good morning guys, just a quick question from a non-techy, what differences does the 1pass/2pass option give?
[12:10] <Mavrik> Wakou: if you're using bitrate as a quality setting, the two-pass options keeps to that bitrate better and gives slightly better quality at same bitrate
[12:10] <Mavrik> Wakou: it has no effect if you're using CRF
[12:13] <Wakou> Mavrik: TY, I am just doing some google readings on the subj, I have found a P2P site where people post cycling video/TV (Hard to get in UK, If you don't have satelite)
[12:14] <Mavrik> Wakou: basically, rule of thumb is: you should use CRF (which is single-pass) unless you want to do direct streaming and/or it's very important your file is of the exact size
[12:14] <Wakou> But my TV won't play Mp4.. (It can 'SEE' the file, title etc, but come up 'unsupported')
[12:15] <Mavrik> Wakou: you should look into "profiles" then - check your TV specification of which H.264 profile and level it supports
[12:15] <Wakou> So I have tried ffmpeg to change to xvid/avi. Which is great, but takes FOREVER!
[12:16] <Mavrik> of course :)
[12:16] <Wakou> The TV is not the best, 'Technika' basically Tesco own brand.. the manual is not too clear on the subj..
[12:16] <Wakou> Here is the relevant page ,,,,
[12:24] <thisisjet> Hello, I would like to save the video feed from my webcam ( /dev/video0 ) to a file using avconv/ffmpeg however I am unable to find out how to turn on the webcam (i just get permission denied.)
[12:24] <thisisjet> can anyone help me with this or point to a tutorial?
[12:24] <thisisjet> thanks
[12:25] <Wakou> http://imgur.com/iECEv
[12:25] <juanmabc> thisisjet: ls -lh the file, group video here
[12:26] <Mavrik> Wakou: it doesn't look like it supports mp4 container
[12:26] <Mavrik> or MPEG4 video for that matter
[12:26] <thisisjet> crw-rw----+ 1 root video 81, 0 Jun 10 22:25 /dev/video0
[12:26] <Mavrik> (H.264 MPEG4 video, sorry)
[12:28] <thisisjet> there is the ls output, but what do you mean by "group video"?
[12:28] <juanmabc> thisisjet: type also $ groups (see if you are in video)
[12:28] <thisisjet> no, i have no group
[12:28] <thisisjet> should i start by addin that?
[12:28] <Wakou> I have been using winff to xvid, works but takes a long time. Could you suggest some setting to make it faster, I am not TOO concerned that the quality is beautiful, but obv I don't want it too grainy/blurry etc..
[12:28] <juanmabc> thisisjet: add yourself to video group (remember to relog in)
[12:29] <Mavrik> Wakou: "Buy a better CPU" :\
[12:29] <Mavrik> Wakou: libxvid doesn't really have much in terms of encoding speed settings
[12:29] <thisisjet> ok thanks, I'll try that
[12:29] <Mavrik> maybe set number of threads
[12:29] <Wakou> :) Oh yes I am lusting after a nice shiny six core beast
[12:30] <Wakou> Would it be quicker if I booted to a console and just ran the ffmpeg?
[12:30] <Mavrik> Wakou: I doubt it... try googling up settings that speed up libxvid
[12:31] <Wakou> Mavrik: TY, I will do that...  No point in encoding to mpeg2?
[12:32] <Mavrik> Wakou: hmm... MPEG2 encoder MIGHT be faster... but you'll have to test it on your hardware
[12:32] <Wakou> Mavrik: TY TY..
[12:32] <thisisjet> do I have to fully log out all sessions of me? or would starting a new bash session be fine?
[12:33] <thisisjet> because that didn't work :P
[12:33] <thisisjet> ahhh
[12:33] <thisisjet> nvmind
[12:33] <juanmabc> thisisjet: fully desktop session
[12:33] <thisisjet> seems i do need to
[12:33] <thisisjet> yes
[12:33] <thisisjet> thanks
[12:33] <thisisjet> brbr
[12:37] <thisisjet> hmmm... I am now in the video group, but still  I can not get permission to the /dev/video0 device..... details: http://fpaste.org/T1Eo/
[12:39] <Mavrik> um
[12:40] <Mavrik> this might not be the best channel to ask about avconv issues, since they changed the interface
[12:40] <Mavrik> but you're certanly missing the -f video4linux2 input format setting
[12:40] <juanmabc> thisisjet: you do know libav is a fork?
[12:41] <thisisjet> no, is ffmpeg still prefered?
[12:41] <juanmabc> also see the man pages for some webcam example
[12:41] <thisisjet> i just am using the default installed pkgs with my ubuntu install
[12:42] <Mavrik> yeah, Ubuntu f*ed up since they symlink ffmpeg to avconv which isn't equivalent
[12:43] <juanmabc> thisisjet: try that (converted to avplay maybe, who knows) $ ffplay -f video4linux2 /dev/video0
[12:44] <juanmabc> the main reason i could think is ubuntu ffmpeg mantainer was part of the forkers of libav
[12:44] <juanmabc> not like ubuntu choose in equality
[12:44] <thisisjet> great, that seems to work... though the -i flag still is giving permission denied.... at any rate, that should b enough for me to take it from here. thanks.
[12:45] <juanmabc> good
[14:08] Action: itrufeng how to use ffmpeg convert wma to mp3.HELP~
[14:34] <smjms> itrufeng: just a moment
[14:36] <itrufeng> smjms: ok
[14:38] <smjms> ffmpeg -i inputfile.wma outputfile.mp3
[14:38] <smjms> replace the filenames
[14:50] <SMJ> because you're encoding already from a lossy compression format, I would use a higher bitrate than the default to avoid further degrading
[15:01] <SMJ> ffmpeg -i inputfile.wma -acodec libmp3lame -aq 3 outputfile.mp3
[15:07] <hwk> how can i get the video duration of a video using ffprobe?\
[15:13] <hwk> i noticed not all movies have the duration information
[15:19] <hwk> im using this: /usr/local/bin/ffprobe -v 0 -show_streams -print_format json myfile.flv
[15:20] <hwk> without the -show_streams option i the info including duration
[15:27] <hwk> or do i need to /usr/local/bin/ffprobe -v 0 -show_streams -count_frame -print_format json myfile.flv and after total_frames/frame_rate to get the duration?
[15:28] <hwk> and also is it possible to limit the output of -show_streams to the video one?
[15:28] <hwk> one/ones
[15:30] Action: hwk slaps ubitux around a bit with a large trout
[15:30] <hwk> around?
[15:30] <ubitux> yay.
[15:31] <hwk> help :)
[15:31] <ubitux> the duration might be in the format, or in the streams
[15:31] <hwk> in my case, neither in those
[15:31] <ubitux> it won't be exact most of the time, and it might not be available in some case (a network stream for instance)
[15:32] <hwk> so the best of getting the duration is to calculate it?
[15:32] <ubitux> the duration doesn't appear with -show_streams and -show_format?
[15:32] <ubitux> on your flv?
[15:32] <hwk> yep
[15:33] <ubitux> can i have a sample?
[15:33] <hwk> pastebin or the video itself?
[15:34] <ubitux> well first, confirm that ./ffprobe -v 0 -show_streams -show_format myfile.flv|grep duration doesn't show the info
[15:34] <hwk> http://pastebin.com/gmxupB0L this is the output
[15:35] <ubitux> this is a strange output
[15:35] <hwk> for /usr/local/bin/ffprobe -v 0 -show_streams -count_frame -print_format json myfile.flv
[15:35] <ubitux> yes
[15:35] <ubitux> and this is this missing -show_format
[15:35] <hwk> oh
[15:36] <hwk> just a second
[15:36] <hwk> my bad :)
[15:36] <hwk> the duration is in [format] sections, thus is missing in [streams]
[15:46] <ubitux> it's not missing
[15:46] <ubitux> the whole presentation has the duration specified in the format section
[15:46] <ubitux> but the duration of each stream is unknown
[15:47] <hwk> so i can rely on the duration in the format section for any video?
[15:48] <hwk> or i need to implement a fallback method for duration calculation
[15:52] <ubitux> i'd take the format duration, and fallback on streams duration
[20:42] <burek> is there any other tool on linux (except ffmpeg/vlc) that can do this:  ffmpeg -f v42l -i /dev/video0 -vcodec ... -f v42l -i /dev/video1 -vcodec ... -f v42l -i /dev/video2 -vcodec ... -f mpegts udp://remoteip:port
[20:43] <burek> shortly, to get an input from multiple input sources and mux it into mpeg-ts over udp
[20:59] <Freakshow> anyone care to review a vpre preset for me?
[20:59] <Freakshow> http://pastebin.com/1FPmmVtQ
[20:59] <burek> those are deprecated
[20:59] <burek> use native x264 presets
[21:00] <Freakshow> but they still work, right?
[21:00] <burek> they are not distributed any more
[21:00] <Freakshow> I know it's deprecated... to some degree 
[21:00] <Freakshow> 'that' I did not know
[21:00] <Freakshow> :P
[21:00] <burek> so, I guess you can try and create them yourself, but you're on your own then :)
[21:01] <Freakshow> haha
[21:01] <Freakshow> thanks
[21:01] <Freakshow> :
[21:01] <Freakshow> D
[21:01] <Freakshow> 
[21:01] Last message repeated 1 time(s).
[21:01] <burek> just type x264 --help
[21:01] <burek> and read -preset -profile and -tune
[21:01] <Freakshow> whoops... sorry, didn't mean to spam that
[21:01] <burek> and specify those at ffmpeg's cmd line with same options (-preset -profile -tune)
[21:12] <Freakshow> can you think of any reason why -vpre wouldn't be honoring an ffpreset in general?
[21:14] <sacarasc> Try using -fpre /path/foo.ffpreset
[21:25] <llogan> Freakshow: some of those options will be ignored
[21:25] <llogan> i think
[21:26] Action: llogan also recommends -preset -profile:v and -tune
[22:46] <Onionnion> wouldn't the line to do deinterlacing and resize a video's size in half be this: ffmpeg -i ~/Dropbox/clips/converts/orig/00018.MTS -vf yadif=0 scale=iw/2:-1 %d.png
[22:46] <Onionnion> oops let me retype that
[22:46] <Onionnion> ffmpeg -i input.MTS -vf yadif=0 scale=iw/2:-1 %d.png
[22:46] <hwk> -vf yadif=0,scale=iw/2:-1
[22:47] <hwk> from what i learned here
[22:47] <Onionnion> I keep getting "unrecognized option '-vf'
[22:47] <llogan> Onionnion: use a pastebin site to show your ffmpeg command and the complete console output
[22:48] <hwk> yeah, the compile flags
[22:48] <hwk> using a precompiled version?
[22:48] <Onionnion> http://pastebin.com/yFqG7zgQ
[22:49] <Onionnion> downloaded from repos, yeah
[22:49] <Onionnion> debian, squeeze
[22:49] <llogan> that does not support filtering, IIRC
[22:49] <hwk> its ages old
[22:49] <hwk> :)
[22:49] <hwk> try compiling the git trunk
[22:49] <Onionnion> Wheezy cannot come soon enough lol
[22:50] <llogan> you can compile and not install but still use it if you don't want to interfere with your installed ffmpeg
[22:50] <hwk> remove ... apt-get remove ffmpeg
[22:50] <Onionnion> isn't there a repo for ffmpeg?
[22:51] <Onionnion> deb-multimedia
[22:52] <hwk> ffmpeg development is very dynamic
[22:52] <hwk> the repos cant keep up
[22:56] <Onionnion> what about dependencies for building
[22:57] <Onionnion> actually I'll just download the stable package
[00:00] --- Tue Jun 12 2012