[Ffmpeg-devel-irc] ffmpeg.log.20111127

burek burek021 at gmail.com
Mon Nov 28 02:05:01 CET 2011

[00:35] <pinkette> is it true that  aacencoder by android is better than  faac or aac-ffmpeg
[00:36] <JEEBsv> IIRC both based more or less on the example implementation sources for an AAC encoder > faac, libvo-aacenc
[00:36] <JEEBsv> ffaac's encoder is still very much a work-in-progress
[00:37] <pinkette> jeebsv sorry can you repeat that?  are you saying  libvo-aacenc >  faac ?
[00:37] <JEEBsv> so I'd say that libvo-aacenc and faac are better than ffaac
[00:37] <JEEBsv> ffmpeg's aac encoder = ffaac
[00:37] <pinkette> i see
[00:37] <JEEBsv> but those two then should be quite similar
[00:37] <pinkette> okay what about  libvo  vs faac then
[00:38] <pinkette> libvo and faac is pretty much same?
[00:38] <JEEBsv> aye
[00:39] <JEEBsv> I think since both base on the example implementation sources, neither of them is really usable for builds that you think about releasing publically
[00:51] <pinkette> what other aac encoder does ffmpeg support
[00:52] <JEEBsv> libaac+ IIRC, which also uses reference implementation code as far as I can remember :D
[00:53] <pinkette> what do you mean by implementation sources/code
[00:55] <JEEBsv> the stuff that's in the AAC's specifications
[00:55] <JEEBsv> there are reference implementations
[00:55] <JEEBsv> and those are not exactly (L)GPL-compatible as far as I know
[00:59] <pinkette> isn't all aac encoder = have to have  aac specs
[01:02] <JEEBsv> yes, of course -- but copying code out of the reference implementation...
[01:02] <JEEBsv> because the specs also contain a decoder and an encoder reference implementation
[01:03] <JEEBsv> Just like you have JM with H.264
[01:59] <faab> hi! i'm converting my ogg music to mp3 so i can put it on my ipod.. 
[01:59] <faab> but the mp3s don't have tags after the coversion!
[01:59] <faab> -map_metadata 0:0 doesn't seem to fix the problem... a little help?
[02:04] <pasteeater> faab: use a pastebin site to show your ffmpeg command(s) and the complete console output(s)
[02:09] <faab> pasteeater: okay.. doing so..
[02:11] <faab> pasteeater: here it is ... http://pastebin.com/EwWLdhkY
[02:11] <faab> and there are no tags in the resultant file..
[02:12] <faab> since i'm planning to do this a large part of my library, i figured it'd be nice if i could get the tags to copy over..
[02:15] <pasteeater> ffmpeg doesn't show any metadata for test.mp3? ffmpeg -i test.mp3
[02:17] <faab> pasteeater: it would appear not: http://pastebin.com/U9L328TF
[02:17] <faab> :(
[02:21] <pasteeater> same for me...although i recall it working previously, and -map_metadata wasn't needed, but maybe i'm mistaken.
[02:21] <pasteeater> and i'm using Git head
[02:23] <faab> i'm using a cygwin build from the cygwin ports project..
[02:23] <faab> ah well..
[02:28] <notfaab> pasteeater: thanks for confirming at least ;)
[02:29] <pasteeater> notfaab: i'm still monkeying with it...
[02:30] <pasteeater> anyone know how to convert a shallow git repo to a "normal" one?
[02:31] <notfaab> pasteeater: you don't have to if you don't want to.. but if you figure it out, thanks!
[02:32] <pasteeater> it's a good distraction
[02:33] <notfaab> pasteeater: i know that feeling
[02:36] <monstaRtruck> pasteeater my sound still out of sync
[02:40] <pasteeater> monstaRtruck: I don't remember your issue
[02:42] <monstaRtruck> i made my movie smaller
[02:43] <monstaRtruck> but its not due to my comp
[02:43] <monstaRtruck> ffmpeg is jsut weird
[02:43] <monstaRtruck> does urs sync if u record a desktop
[02:43] <monstaRtruck> im trying to record a video game
[02:44] <pasteeater> i don't have any video games
[02:44] <pasteeater> except dungeon crawl
[02:44] <pasteeater> do you have a sample of your output?
[02:44] <monstaRtruck> yes
[02:44] <monstaRtruck> ther is some commant that will pull the sound back
[02:45] <pasteeater> huh?
[02:45] <monstaRtruck> my sound is 3 seconds late
[02:55] <pasteeater> notfaab: duh. not working for me. why didn't i notice this before?
[02:56] <notfaab> pasteeater: notice what?
[02:58] <pasteeater> the metadata not copying from in to out
[03:02] <notfaab> you mean, it didn't work for you way-back-when you remembered it working? :P
[03:05] <pasteeater> i don't remember
[03:07] <monstaRtruck> pasteeater how come its out of sync
[03:07] <monstaRtruck> so many ppl complaining theirs out of sync too
[03:08] <pasteeater> i don't know.
[03:08] <monstaRtruck> hav u ever tried recording desktop
[03:26] <notfaab> pasteeater: i'll just use musicbrainz picard to retag all the albums..
[03:26] <notfaab> thanks though! have a nice night..
[07:47] <kcm1700> ls -altp
[07:47] <kcm1700> oh, sorry.
[10:06] <cryptopsy> can ffmpeg be used to make sounds deeper?
[10:07] <cryptopsy> as in, have someone's voice sound deeper
[10:08] <cryptopsy> also known as the pitch ?
[10:10] <cryptopsy> apparently sox can do it
[10:16] <cryptopsy> what's the operation where you remove scratchy background noise from recordings?
[10:16] <o3u> hi, i would like to stream selected videos that are processed by ffmpeg, i'm thinking of doing it by creating a pipe (lets say pipe.mp4), and use jsvideo on a webpage to read that pipe, it would involve running ffmpeg continuously until visitor leaves page, does anyone know if this would work?
[10:17] <cryptopsy> hiss reduction
[10:17] <cryptopsy> that's it
[10:17] <o3u> ffmpeg would output to the pipe, my player would read from it
[10:18] <cryptopsy> you want to video the result as it's being processed?
[10:18] <cryptopsy> view
[10:19] <o3u> pretty much, it can be processed slightly ahead of time, 
[10:20] <cryptopsy> what you said didn't make sense
[10:20] <cryptopsy> a <-stream-> b 
[10:20] <cryptopsy> which direction?
[10:23] <o3u> i have a bunch of videos i'd like to put together, concatenate so to speak, and before that happens they need to individually be processed by ffmpeg, once processed and concatenated they're streamed to my video player, however the whole concatenation only happens once the visitor is on the webpage, it cant happen before, and it must be done live
[10:23] <o3u> or "almost" live, i don't really understand your diagram there
[10:47] <cryptopsy> you don't have to concatenate them into one file
[10:47] <cryptopsy> you can have your website play one after the other
[10:47] <cryptopsy> for example if you play music in mplayer this way you can't tell two songs apart, same with video
[10:47] <cryptopsy> make sure the end of clip n lines up with the start of clip n+1 and its file
[10:48] <cryptopsy> have your website cache the video so its there for playing when the previous is finished
[15:19] <muffin_666> hey all, I have a strange problem with decoding mpeg4/aac: if I try to open the file by the standard-way (without custom IO) the file gets played nicely, however, if I try to use custom callbacks, av_read_frame() will never find packets from the audio stream, even if the audio stream is set correctly and the av_dump_format() prints out everything correct. The result is that my audioQueue is never filled. But the custom IO works fine with oth
[15:19] <muffin_666> er files e.g. h264/aac. Does anybody have an idea what might be wrong? (here is my code: http://pastebin.com/9znPAXCp)
[16:30] <masch> hi. 
[16:31] <masch> Log: http://pastebin.com/N9JUSZv4   | Config: http://pastebin.com/7m1q93uN  can anyone tell me whats wrogn? 
[18:47] <CSMan> is there a way to specify mp4 output?
[18:47] <CSMan> like you do -f flv to create flv files
[18:47] <sacarasc> How about... -f mp4
[18:47] <sacarasc> :O
[19:04] <parkeyparker> Is anyone here using ffmpeg to encode HTML5 compatible videos? If you are what bitrates are you aiming for for a good balance between quality and file size?
[19:04] <blez> hello
[19:04] <blez> how to extract a frame from flv/mp4 if I had only a partial content from it
[19:04] <blez> without the beginning
[19:14] <ticapix> Hi
[19:16] <ticapix> using ffmpeg is there a way to change the fps property of a avi (mjpeg) ? without actual modifying the video (no frame being removed or duplicated), just the property of speed playback.
[19:17] <CSMan> how can I get ffmpeg to use all my cpu power?
[19:20] <ticapix> The way I do it now is to convert my video to y4m and edit manualy the file to change fps in the header. I'n sure there is a smarter way, no ?
[20:07] <michaelni> blez, using h263 / h264 raw demuxer may work
[20:08] <blez> how to do that
[20:09] <michaelni> -f h263 or -f h264 but theres a high chance it will not work
[20:10] <blez> is there a way to get the last frame in one command?
[20:33] <kriegerod> does anybody know what bug in transcoding h264 application, that uses libavcodec & x264, can cause grey crap like this http://tinypic.com/r/24en86r/5 instead of normal pic. This appears after several hours of good transcoding work
[21:18] <Foxhoundz> Is there any way to make ffmpeg guess the format of the input file? The file doesn't have any extension attached to it.
[21:18] <Foxhoundz> And this is for the ffmpeg binary on windows
[21:20] <parkeyparker> Foxhoundz: you might need to detect that yourself with a script before passing it to ffmpeg...
[21:20] <parkeyparker> Unless there is something mentioned in the documentation about it?
[21:21] <parkeyparker> As to what script you would use I don't know... However I'm sure there is some form of application/script that will look at the header section of the video and work out its extension for you automatically
[21:25] <iive> Foxhoundz: ffmpeg is supposed to guess the file type by content and use the extension as hint. there is ffprobe too.
[21:26] <parkeyparker> Ah ok, I always like to be corrected when it comes to features I didn't realise existed :P
[21:26] <Foxhoundz> It's giving me an unknown format when I do it
[21:26] <Foxhoundz> ffmpeg.exe -i "testFile" -ab 192k test.mp3
[21:27] <Foxhoundz> I think I need to add in the -f switch too
[21:27] <Foxhoundz> nevermind
[21:28] <Foxhoundz> -f only forces a specific output format
[21:28] <iive> Foxhoundz: if it can't recognize it, then it is bad...
[21:28] <parkeyparker> However forcing the output might be better than it trying to use the same output than input
[21:28] <Foxhoundz> iive: It's an FLV file and it's not corrupted
[21:29] <iive> Foxhoundz: are you sure you use recent ffmpeg ?
[21:29] <Foxhoundz> It's a few months old
[21:29] <iive> flv should be easy to guess.
[21:29] <Foxhoundz> I'll try to get the latest one and give it a shot
[21:30] <iive> rename it, and see if ffmpeg guesses it then.
[21:31] <iive> btw, are the first 3 bytes of the file data content a "FLV" string?
[21:32] <Foxhoundz> back
[21:32] <Foxhoundz> ok I downloaded the latest version
[21:32] <Foxhoundz> and it worked
[21:32] <Foxhoundz> It seems that my version was a year or so old
[22:27] <darkstarbyte> How would I find out the audio bit rate of something?
[23:18] <pasteeater> kriegerod: does the gray occur in all players?
[23:19] <kriegerod> i test it on ffplay only
[23:19] <pasteeater> use a pastebin site to show your ffmpeg command(s) and the complete console output(s)
[23:20] <pasteeater> darkstarbyte: bitrate = file size/duration, or see what 'ffmpeg -i input' says.
[23:21] <darkstarbyte> I thought that does not work because h.264 can compress files really well
[23:21] <darkstarbyte> and
[23:21] <darkstarbyte> have the same quality of mpeg2
[23:46] <pasteeater> darkstarbyte: you asked about audio bitrate. what's H.264 have to do with that? i assumed you meant an audio file.
[00:00] --- Mon Nov 28 2011

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