[Ffmpeg-devel-irc] ffmpeg.log.20140123

[burek]

[00:45] <cuba> hey
[00:45] <cuba> when encoding images with huffyuv or ffv1 and very low framerates like 1fps i get a video
[00:46] <cuba> but its just the same image
[00:47] <cuba> http://pastie.org/8658649
[00:47] <cuba> -r can also be 1 or 2 without any change
[00:47] <klaxa> >to show your EXACT ffmpeg command and the COMPLETE console output.
[00:47] <klaxa> i don't see any output
[00:47] <cuba> oh sorry
[00:48] <klaxa> if it's a windows terminal and you can't copy paste, a screenshot is fine too
[00:49] <cuba> http://pastie.org/8658654
[00:49] <cuba> na its fine i use cygwin
[00:50] <klaxa> >frame=  200 fps=2.6 q=-1.0 Lsize=   18729kB time=00:04:45.71 bitrate= 537.0kbits/s dup=0 drop=6855
[00:50] <klaxa> your frames are being dropped, i don't see why exactly though
[00:52] <cuba> without setting -r it works fine
[00:52] <cuba> maybe such low framerates are not supported
[00:53] <klaxa> i don't think so, but i can be wrong, can you try with -r 30 and see if that works?
[00:53] <cuba> yes that works
[00:54] <klaxa> that's weird
[00:55] <cuba> seems like everything under 25 wont work
[00:55] <klaxa> is there a reason you use ffv1 and avi?
[00:55] <cuba> >=25 does not drop
[00:55] <cuba> no not really which container shall i use?
[00:55] <klaxa> i personally use x264 and mkv for almost anything
[00:56] <cuba> same issue
[00:58] <klaxa> let me extract some frames from a video and try what you are doing
[00:58] <cuba> ah its the argument handling i think
[00:58] <cuba> but ive to download the movie
[00:58] <cuba> maybe it must stand in front
[00:59] <cuba> yep
[01:00] <cuba> as second argument it works very nice
[01:00] <cuba> thank you very much klaxa
[01:03] <klaxa> so did it work?
[01:03] <klaxa> sorry my system just crashed because >lol 2 gb ram
[01:03] <cuba> yes
[01:03] <cuba> seems like it needs to stand upfront
[01:03] <cuba> then it works perfectly
[01:04] <cuba> even with -r 0.73
[01:04] <klaxa> ah err... yeah that makes sense
[01:04] <cuba> not really, does it?
[01:05] <klaxa> no it does
[01:05] <klaxa> you put it before -i right?
[01:05] <cuba> yes
[01:05] <klaxa> that makes sense because that sets the input framerate of your images to 0.7 fps
[01:06] <klaxa> instead of taking whatever is default (maybe that's even 0) and then set the framerate for the output to 0.7
[01:06] <cuba> ah okay
[05:00] <GregDR> I have question about fragmented MP4 files&  Is it legal to have a single sample group description box ('sgpd') in the 'moov' while each 'traf' has only a sample to group box ('sbgp') that references it?  Or must the 'sgpd' and 'sbgp' always exist together in the same container box?
[08:33] <x_> If I use ffmpeg like this: ffmpeg -f flv test.flv I am able to record my desktop with 0 xruns, however as soon as I try to do -f flv 'rtmp://someserver.com/feed' I instantly get a few xruns. The xruns last for only a second or two, as thing seem to 'stabilize' if you will, and never happen again. The problem is the audio is not synced with the video when the xrun occur.
[09:07] <xlinkz0> is there any image format that supports YUV?
[10:37] <ussher_> Im trying to merge 2 stereo mp3 files.  When they are of different lengths the length of the merged file is the length of the shorter mp3.  Is there a way to loop one file so it returns to the beginning while until the main file completes? http://pastebin.com/TPV9FwvN
[10:51] <ussher_> figured it out.  make sure the overlay-track is always longer than the target file. thanks.
[11:06] <Winston__Smith> ez
[11:39] <x_> How come one xrun desyncs the audio permanently is there a way to make it detect this and rsync the audio as its going?
[11:40] <x_> Trying to record my desktop for live view.
[11:42] <x_> I see -async but I have not had luck with it.
[11:42] <x_> aresample
[11:50] <x_> "Stretch/squeeze samples to the given timestamps, with a maximum of 1000 samples per second compensation:" what given timestamps?
[11:55] <ussher_> x_: i've been having good luck recording 720p  with this command http://pastebin.com/2gBvXMQt
[11:57] <Winston__Smith> i played a bit with windows overlay ... here my result http://lpc.fioresardo.net/up/%C2%A9%20Lino%27s%20Screensaver%202.0.exe <<< play any video in overlay modus (dvbviewer or mediaplayer classic for example) and when screensaver switches on continous watching
[11:57] <Winston__Smith> windows 7 compatible
[12:01] <x_> ussher_, in the event of an xrun I don't want it to permanently desync
[12:02] <x_> ussher_, I can record fine but rather then stopping xruns all together rather try to handle them.
[12:02] <ussher_> x_:  your probably better at ffmpeg thatn me. i'd need to look up both of those terms to know what your talking about.  I've been doing a lot of screencasts with the above set of params and its been working.
[12:05] <x_> ussher_, ah I see, thanks for your input! ;)
[12:30] <x_> https://trac.ffmpeg.org/ticket/2420 wondering the same thing, but this is not very helpful.
[12:43] <x_> It is very really unclear that you need to have --enable-avresample set for that filter to be enabled.
[12:43] <x_> very really ha oops
[14:01] <x_> Is there a way to make ffmpeg print out the timestamps it refers to?
[14:23] <average> x_: erm..vague question, rephrase
[14:24] <relaxed> x_: version?
[14:30] <x_> so my video pts_time:0.190476 and my audio pts_time:1.19473 are not the same how do I make sure they are always the same or close to the same. like on the fly audio video sync.
[14:30] <x_> or is that even what I am looking for? I am not even sure if this would actual keep audio and video in sync in the event of an xrun or something
[15:04] <x_> relaxed, What I am asking is, is there a way of keeping audio and video in sync on the fly?
[15:07] <x_> async vsync and filters like asyncts are not what I am looking for I think.
[15:10] <x_> as they just make sure the rates for audio and video are consistent as far as I understand.
[15:11] <x_> looks like concat may do what I want.
[15:13] <x_> scratch that.
[15:28] <Mavrik> x_, you're looking for solution at the wrong place
[15:28] <Mavrik> if you have a discrepancy between audio and video
[15:28] <Mavrik> then there's something wrong with the thing that sets those PTS values
[15:28] <Mavrik> ffmpeg can't magically know what's synced if timestamps are wrong :)
[15:36] <x_> [Parsed_ashowinfo_0 @ 0x1f64120] pts_time:1.42942 [Parsed_showinfo_0 @ 0x1fa0860] pts_time:0.0952381  So it does not really know?
[15:36] <x_> when the video and audio are in sync the pts_times do match up and they don't when the video is not in sync.
[15:38] <x_> Maverick,
[15:38] <x_> Mavrik,
[15:38] <x_> huh
[15:40] <Mavrik> <x_>	 when the video and audio are in sync the pts_times do match up and they don't when the video is not in sync.
[15:40] <Mavrik> yea no kidding
[15:40] <Mavrik> that is kinda the point :P
[15:41] <x_> yeah? then why do they become desynced then?
[15:41] <x_> the timestamps are correct
[15:41] <x_> it correlates to what is on screen the audio is behind by about one second.
[15:41] <relaxed> x_: are you using a recent version of ffmpeg?
[15:41] <Mavrik> PTS TELL the player on when to show a video frame
[15:41] <Mavrik> or audio frame
[15:42] <x_> I am using a git version
[15:42] <Mavrik> if your PTS are not correct, your A/V will not be in sync
[15:42] <relaxed> Just checking
[15:42] <Mavrik> so you're somehow changing (or improperly generating) your PTS in input vidoes
[15:42] <Mavrik> *videos
[15:42] <Mavrik> since I didn't see where your source comes from and what you're doing exactly... I can't help more than that.
[15:43] <x_> So the fact that the pts will be in sync with the output but when there is an xrun the pts no longer matcxh
[15:47] <x_> Mavrik, ffmpeg is setting the pts as far as I understand, I am capturing with x11grab and jack.
[15:49] <x_> Mavrik, Also ffmpeg will report one xrun at the beginning of the output, but never again. However the xrun will only occur if I output the file via -f flv 'someserver' other wise -f flv test.flv won't have the same behavior.
[15:49] <x_> Jack does not report an xrun.
[15:50] <x_> getting a pastebin
[15:54] <x_> http://pastebin.com/eUw9SBuW to server, http://pastebin.com/1zNdXuBT to local file
[15:55] <Mavrik> well, it seems either x11grab or jack don't properly signal their timestamps
[15:56] <x_> Mavrik, so the fact that it only xrun when I send it to a server is jacks or xorgs fault?
[15:56] <relaxed> x_: try -framerate 21
[18:52] <LucaS05> hi. do you know where can i find an analysis of the xvid format? i don't know where to ask
[18:54] <Zeranoe> LucaS05: What sort of analysis are you looking for?
[18:54] <LucaS05> how it is composed and how the compression happens (the steps)
[18:55] <LucaS05> maybe you have a pdf or something
[19:06] <JEEB> 14496-2
[19:06] <JEEB> is the format's specification
[19:06] <JEEB> MPEG-4 Visual
[19:06] <JEEB> divx/xvid and avcodec's 'mpeg4' implement this format
[19:09] <LucaS05> do you have a link?
[19:11] <JEEB> http://lmgtfy.com/?q=14496-2+.pdf
[19:13] <LucaS05> thanks :D
[19:17] <JEEB> not sure why you want to know about that format, though
[19:32] <x_> JEEB, I am experiencing an Audio packet xrun as I start to broadcast via -f flv <server_address> by not when I do as such -f flv test.flv any ideas? It actually offsets the audio by about one second.
[19:33] <x_> but not when I do as such*
[19:33] <x_> the audio does not get offset when I output by the ladder.
[20:33] <simmerz> Hi, is it possible to composite a bunch of videos on top of each other, and then scale the whole composition down, in one command? I'm using complex_filter to do the first bit, but not sure if I can do the second at the same time
[21:02] <simmerz> answered my own question :)
[21:03] <juke_> hi
[21:04] <juke_> hi take capture of a stream with ffmpeg -i "rtsp://mafreebox.freebox.fr/fbxtv_pub/stream?namespace=1&service=372" -vf select='gt(scene\,0.2)' -vsync 0 -f image2  image%3d.png
[21:05] <juke_> how can i obtain better quality than http://digitalashram.org/explode2/image046.png ?
[21:30] <maujhsn> I Would like to clone an older version of ffmpeg that I still like How is this done using the git repository?
[21:34] <clever> git log, find the hash of the version you want, git checkout hash
[21:41] <maujhsn> clever...Is it just that simple?
[21:41] <JEEB> yes
[21:42] <maujhsn> JEEB where is the git log location in '10.04"?
[21:42] <maujhsn> Or is it?
[21:43] <JEEB> uhh
[21:43] <JEEB> easiest way would be to run the ffmpeg binary and see the git hash noted :P Unless that really is from 2010 and was before the svn->git move
[21:43] <JEEB> if it is the svn, then it would note the svn revision there, and you should be able to grep the git log for that
[21:43] <JEEB> to get the hash
[21:44] <maujhsn> JEEB  Yes this would be 2010, 2011!
[21:44] <JEEB> just run the bloody binary to see the revision or hash :P
[21:47] <maujhsn> JEEB Thanks for the tip! I'll check into it!
[22:24] <slavko> hello
[00:00] --- Fri Jan 24 2014