[Ffmpeg-devel-irc] ffmpeg.log.20120902

burek burek021 at gmail.com
Mon Sep 3 02:05:01 CEST 2012


[02:40] <miszka> Hello. :)
[02:41] <miszka> I'm trying to convert uncompressed .avi to x264+AC3 in .mkv and so far have failed... No errors, video plays well in ffplay... and *only* in ffplay.
[02:41] <miszka> Both mplayer and vlc player display garbled grey frame. Sound is ok, though.
[02:41] <miszka> Using .avi container gives the same result... So does using AviSynth as input.
[02:41] <miszka> What is interesting: I tried to convert a fragment of a random Xvid movie -- and its x264 version plays back correctly everywhere. :O
[02:43] <miszka> Command used: ffmpeg -i input.avi -vcodec libx264 -preset medium -crf 19 -acodec ac3 output.mkv
[02:44] <miszka> Not really... exotic, I'd say.
[03:39] <Azelphur> If I have a MP4 file with "Stream #0.1(und): Audio: aac, 44100 Hz, stereo, s16, 151 kb/s" audio, is it possible for me to strip the audio out without a encode job? (so I'm just left with an audio file and no video)
[03:40] <Azelphur> ie I just want the audio out without having to spend the next ~20 hours at 100% CPU :P
[03:42] <sacarasc> ffmpeg -i input.mp4 -vn -c:a copy output.mp4
[03:43] <Azelphur> sacarasc: unrecognised option c:a
[03:43] <sacarasc> Then you're using a rather old version, try -acodec instead of -c:a
[03:44] <Azelphur> cool, that worked ty :)
[04:52] <hellop> Hello.  When I capture from a webcam how can I make the stream more Variable Bitrate?  I have tried various combinations of -vb and -minrate -maxrate, but the bitrate is close to constant.  I expect if I put a piece of tape over my cam, the bitrate should drop, but it doesn't.  Any clues?
[04:55] <darkstarbyte> The stream could be coming out encoded.
[04:55] <hellop> here's my command: ffmpeg -re -f dshow -s 640x480 -r 15 -i video="Webcam" -c:v libx264 -vb 400k -f mpegts udp://127.0.0.1:10000?pkt_size=1316
[04:55] <darkstarbyte> Your using x264
[04:56] <darkstarbyte> use --crf 23 and see if you like the quality.
[04:56] <hellop> yes.
[04:56] <darkstarbyte> and remove the -vb 400k also
[04:57] <darkstarbyte> The bit rate should vary just using -b with x264
[04:57] <darkstarbyte> Taking bits from low action scenes and giving it to higher action scenes.
[04:58] <hellop> -crf 23 seems to be the default.
[05:00] <darkstarbyte> I know, but ffmpeg can mess up the options.
[05:04] <hellop> ok, tks.  So, I guess for VBR, you would need a large input buffer (somewhere, somehow) so that the encoder knows to reduce compression....  right?
[05:09] <darkstarbyte> Not really.
[05:09] <darkstarbyte> I would ask in the #x264 channel specifically.
[05:09] <darkstarbyte> I mean they would have a better answer.
[05:10] <hellop> darkstarbyte: FYI: I got "Please use -b:a or -b:v, -b is ambiguous"
[05:11] <darkstarbyte> I said don't use those -b* options
[05:11] <darkstarbyte> Unless your trying to get a certain file size exactly which case you would use two passes, and one pass to get close to the file size.
[05:12] <darkstarbyte> -crf if you don't care how big the output size is.
[05:13] <darkstarbyte> and you just want it smaller.
[05:22] <hellop> I want to stream the webcam, so I have to set a max bitrate.  I'm trying to use ffmpeg to get some better quality than with Flash.
[05:23] <hellop> I had some success using 12bit color depth.
[05:23] <hellop> But, I feel that when I cover up the camera the bitrate should instantly drop to like 10kbps.  But, it hardly budges.
[05:47] <hellop> I can't figure it out.  Settings like this don't seem to do what they're supposed to: " -b 256k -minrate 128k -maxrate 512k -bufsize 8192 -g 300 "
[05:48] <hellop> I can't figure out what to put... since there's just a bunch of different suggestions out there.  You say "don't use -b*"  But before you said "The bit rate should vary just using -b with x264".
[05:48] <hellop> Who can you trust in the world of ffmpeg?  no one.  not even yourself.
[05:57] <hellop> The docs: --vbv-maxrate <integer> (x264) -maxrate <integer> (FFmpeg)
[05:58] <hellop> You would think the doc writer would understand specifying what unit the "integer" is, would be crucial to the reader.
[06:00] <hellop> I will pay 50Euros/hr to anyone who can skype me and explain how to figure out how to use these options.
[06:23] <hellop> I am burning 1 Euro per minute until someone helps me.
[07:46] <hellop> I found this info on ffmpeg ratecontrol, which helped a bit: http://ffmpeg-users.933282.n4.nabble.com/attachment/935622/0/ratecontrol-notes.txt
[13:24] <Multbrelch> Hello. I have a problem compiling ffmpeg after this guide: https://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide  (OS: Ubuntu 12.04, 64Bit)
[13:25] <Multbrelch> executing 'ffmpeg' yields: ffmpeg: error while loading shared libraries: libfdk-aac.so.0: cannot open shared object file: No such file or directory
[13:25] <Multbrelch> I used this Install script: http://pastebin.com/NXjF2iEZ and this was the output: http://pastebin.com/vMWh3x5p
[13:26] <Multbrelch> The installation was 'successful' but ... ffmpeg gives me this output. Any idea?
[13:32] <saste> Multbrelch: is a problem with libfdk-aac.so
[13:32] <saste> check that it is really installed in the correct place
[13:33] <saste> as a workaround, you may just disable it when configuring ffmpeg
[13:33] <Multbrelch> hi saste ... where is it normally located?
[13:33] <saste> /usr/lib
[13:33] <Multbrelch> not here? : /usr/local/lib
[13:33] <Multbrelch> I will have a look
[13:34] <Multbrelch> its not in /usr/lib
[13:35] <saste> so that's it
[13:35] <saste> it should fail when configuring ffmpeg, if it can't find the lib, so there may be something fishy
[13:36] <Multbrelch> I found it here: http://pastebin.com/QmTpDTt3
[13:36] <Multbrelch> in /usr/local/lib
[13:37] <joeyjones> hhmm...
[13:37] <joeyjones> ffmpeg libavcodec seems to be what's killing off my windows compile of mplayer
[13:37] <joeyjones> ironically everything encoded fine yesterday...
[13:37] <Multbrelch> BTW, I just found this comment: http://ubuntuforums.org/showthread.php?p=12208567 (see last comment)
[13:39] <saste> Multbrelch: where is ffmpeg installed?
[13:39] <Multbrelch> ffmpeg: /usr/local/bin/ffmpeg
[13:40] <Multbrelch> saste^
[13:41] <saste> Multbrelch: ldd ffmpeg
[13:41] <Multbrelch> ldd: ./ffmpeg: not regular file
[13:41] <Multbrelch> ?
[13:41] <joeyjones> ok, wtf
[13:42] <joeyjones> i pulled the head from git and now ./configure fails
[13:42] <saste> Multbrelch: ldd /complete/path/to/ffmpeg
[13:42] <Multbrelch> http://pastebin.com/R1jQZNEf <= ldd /usr/local/bin/ffmpeg
[13:43] <Multbrelch> yep there it is ^ already understodd :)
[13:43] <Multbrelch> saste, ^
[13:44] <saste> Multbrelch: Ok, so it is only looking in /usr/lib, when you installed custom lib in /usr/local/lib
[13:44] <Multbrelch> okay ...
[13:44] <saste> try this: export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
[13:44] <saste> and run ffmpeg
[13:44] <saste> you may need to set your environment in order to look for library in the correct path
[13:44] <Multbrelch> I think you got it! so far it starts
[13:45] <saste> Multbrelch: it is nothing ffmpeg specific to be clear, but people have problems about it all the time, so maybe we should mention such issues in the docs/wiki
[13:45] <Multbrelch> Somebody should put this info into the Wiki (https://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide)
[13:45] <Multbrelch> Yes as ^
[13:46] <saste> Multbrelch: are you volunteering? ;-)
[13:46] <Multbrelch> Hehehe
[13:46] <Multbrelch> Wot do you mean?
[13:46] <Multbrelch> I'm new to ffmpeg
[13:46] <saste> don't need to be perfect
[13:46] <Multbrelch> ... and compiled ~4 times a program under Linux
[13:46] <saste> once it's there it's easy to fix it
[13:46] <Multbrelch> so ...
[13:47] <saste> ok as you prefer
[13:47] <Multbrelch> I shall modify the page?
[13:47] <saste> you can if you want
[13:47] <Multbrelch> Ah, open source ...
[13:47] <joeyjones> Multbrelch: just don;t go and deface anything :p
[13:47] <Multbrelch> Okay, I will see .. I need to register ...
[13:47] <Multbrelch> haha
[13:47] <joeyjones> otherwise ANON  will get you...
[13:48] <Multbrelch> Wait ...
[13:48] <Multbrelch> ANON = ?
[13:48] <joeyjones> wow
[13:48] <joeyjones> uumm...
[13:48] <joeyjones> never mind
[13:49] <Multbrelch> What I can do is to put a note in Section "Finish"
[13:49] <Multbrelch> "Note that it might happen that one has to set a environment path variable ....  blabla"
[13:49] <Multbrelch> You can correct afterwards ...
[13:49] <Multbrelch> saste, joeyjones ^
[13:53] <saste> Multbrelch: seems ok
[13:56] <Multbrelch> saste, I have an account for the ffmpeg forum (http://ffmpeg.gusari.org/). Do I need a new account for http://ffmpeg.org/?
[14:00] <Multbrelch> yes I need
[14:00] <Multbrelch> ...
[14:41] <Multbrelch> saste, see here: https://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide
[14:41] <Multbrelch> I have written a note
[14:42] <saste> Multbrelch: thanks
[14:43] <saste> for the future, when you do a change add a description, so it's easier to understand what has been done
[14:43] <saste> https://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide?action=history
[14:43] <Multbrelch> Yep, I just recognized that ...
[14:44] <Multbrelch> I will do ... In any case, I will compile the thing also on other three machines ... lets see if it is a 'systematic' thing ...
[14:44] <saste> ubuntu?
[14:45] <Multbrelch> yep, ubuntu 12.04 64Bit, 3x
[14:45] <saste> i expect so, unless you customized your LD_LIBRARY_PATH to point to /usr/local/lib
[14:45] <Multbrelch> No I didn't
[14:46] <saste> as alternative you may install in /usr/, but that would clash with system libraries
[14:46] <saste> so it's not advised
[14:46] <Multbrelch> So seems to be a systematic 'point'
[14:46] <saste> (unless you really know (TM) what you're doing)
[14:59] <Multbrelch> saste, thx for all I need to go, I tell you what I will find on the other two systems ...
[14:59] <Multbrelch> cheers
[19:27] <seablade_mbp> Is there a way to tell ffmpeg not to create the 'ffmpeg2pass*.log.temp' files, or to place them somewhere not in the CWD? (Ideally /var/log/ffmpeg or /tmp?)
[19:30] <saste> seablade_mbp: -passlogfile ?
[19:30] <seablade_mbp> saste, I am seeing references to x264 encoding not supporting that, is that still the case(These are old pre1.0 reports)?
[19:31] <saste> which version do you have?
[19:31] <saste> should be fixed in latest git
[19:32] <seablade_mbp> saste, Well on os x with 0.11.1 apparently, built Aug23.  Haven't tested it, was asking since i saw the reports of that(And currently am converting a video file so once that is done I can test in about 5 more minutes hopefully is my guess
[19:33] <seablade_mbp> Built via brew
[19:33] <saste> 0.11.1 is still borken
[19:33] <seablade_mbp> Hmm
[19:33] <seablade_mbp> So I need to go through and build my own, this should be a nice headache and a half
[19:34] <saste> but you should still be able to use libx264 -stats option
[19:34] Action: seablade_mbp googles the -stats option
[19:39] <seablade_mbp> saste, So I would use ' -x264opts stats=/tmp/ffmpeg2pass.log ' on both of the passes correct?
[19:39] <saste> so i guess
[19:40] <seablade_mbp> HehHeh you sound so assured:)  Ok will give it a shot, thankfully it should be pretty easy to add it into my conf files for this to test it
[20:03] <seablade_mbp> saste, Didn't get stats working, but found that I could build from git HEAD with Homebrew on OS X fairly easily so built that and am testing out the passlogfile, so far it seems to be working thanks
[20:03] <saste> good
[20:04] Action: seablade_mbp loves seeing activity monitor report 1500% CPU usage and 230+ fps on encodes:)
[20:33] <Darkyen> Hey all , What sample_fmt does the liblame encoder supports ?
[20:33] <Darkyen> in the ffmpeg ??
[20:33] <Darkyen> ** libav
[20:37] <Darkyen> erm :?
[21:43] <STrRedWlf> Heya. Is there any way of telling ffmpeg not to resize any arbitrary video if it's under the size I give it (ether -s or the scale filter)?
[21:47] <Multbrelch> saste, hello?
[21:47] <Multbrelch> I compiled ffmpeg also on the other machines: same result
[22:10] <kode54> in any implementations using fdk-aac encoder, does it correctly use padding and MP4 chapters for gapless encoding?
[22:10] <kode54> padding should be using LPC for best result
[22:12] <JEEB> I think stuff like that isn't encoder-specific and your implication that there is such a thing as "mp4 chapters" makes me laugh
[22:12] <JEEB> because if you look at the ISO specs you don't have chapters anywhere
[22:12] <JEEB> there are two nonstandard ways of putting chapters into mp4, sure
[22:13] <JEEB> one being the thing that Nero made up, and another being mov chapters. The latter specifically is now written in the specs that it shouldn't be used and the first one never even went close to the specs (before it was just something that was reserved as an atom name)
[22:31] <phalaris> hi
[22:33] <phalaris> i know, it's offtopic, but yesterday there was some one here who helped me with the program reaper
[23:32] <buhman> so I do: ffmpeg -i CAPTURE-HD-RM164_2012-08-20_13_21_28.ts -an -vcodec mpeg2video -q 0 video.mpg; ffmpeg -i CAPTURE-HD-RM164_2012-08-20_13_21_28.ts -vn -acodec pcm_s16le -q 0 audio.wav
[23:32] <buhman> audio.wav ends up being 1:30:00, and video.mpg ends up being in excess of 3 hours
[23:33] <buhman> audio.wav is the correct speed, and video.mpg is at least twice as slow as it should be
[23:33] <buhman> what erm, is going on?
[23:41] <barhom> I can't seems to control BW on this; ffmpeg -re -loop_input -i error503.jpeg -vcodec mpeg2video -f mpegts udp://239.192.200.200:3301
[23:41] <barhom> its giving me something like 2000kbit, and thats really not what I want
[23:41] <barhom> its only 1 frame its going to loop really
[23:42] <buhman> video: http://sprunge.us/OJRY audio: http://sprunge.us/cOQY wtf?
[23:43] <buhman> how does that make sense?
[23:44] <buhman> but that 59.94 tbc looks suspicious
[23:45] <barhom> http://pastebin.com/aNyWxt7u < you can see I limited to 10K just to test, but the output is something like 1500kbits
[00:00] --- Mon Sep  3 2012


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