[Ffmpeg-devel-irc] ffmpeg.log.20140125

Sun Jan 26 02:05:01 CET 2014

[04:39] <fundies> Error: Track 2 with the CodecID 'S_VOBSUB' is missing the "codec private" element and cannot be extracted. How to fix?
[05:10] <fundies> relaxed, mkvextract cant extract vobsub from mkv created w/ ffmpeg
[05:11] <fundies> mkvextract tracks dvd.mkv 2:vobsub
[05:11] <fundies> ffmpeg -fflags genpts -i dvd.mpg -c copy -map 0:1 -map 0:2 -map 0:3 -map 0:4 -map 0:5 dvd.mkv
[05:15] <relaxed> fundies: does it work if you remux with mkvmerge instead of ffmpeg?
[05:17] <fundies> mmg doesnt copy over the vobsubs at all
[05:19] <relaxed> maybe someone in #matroska has an idea
[05:52] <smit> where can I find the windows binary for ffserver? it's not in the packages on http://ffmpeg.zeranoe.com/builds/
[06:11] <dantxo> Hello.
[06:11] <dantxo> I'm using ffmpeg to stream audio and video form a webcam.
[06:12] <dantxo> whenever I reboot my computer the /dev/video* devices get reordered
[06:12] <dantxo> so I can't trust that video1 is always the webcam
[06:12] <klaxa> can't you create udev rules for that?
[06:13] <dantxo> Is there a way to identify the video source by hw id or something? like what I doo with the audio part
[06:15] <dantxo> klaxa: thank you
[06:25] <bmuk> Hey everyone I'm trying to record my desktop and I'm getting terrible performance (1-4 fps). I'm not really sure what I am doing wrong. ffmpeg -video_size 1024x768 -framerate 25 -f x11grab -i :0.0+100,200 output.flv this is the command I am using
[06:26] <bmuk> the x server is using insane amounts of cpu while this runs, but this itself only uses 3%
[06:27] <relaxed> dantxo: do you have /proc/videodev ?
[06:30] <bmuk> http://pastebin.com/D7kTXaeL
[06:30] <bmuk> that is the command followed by the output
[06:32] <relaxed> bmuk: add -c:v libx264 -preset:v veryfast after the input
[06:34] <bmuk> I'm still getting 3-4 fps
[06:34] <relaxed> OS? cpu?
[06:35] <bmuk> arch linux, 3.12.8-1. amd fx 6300
[06:35] <dantxo> relaxed, sorry I was away from the computer, there is no videodev under /proc/
[06:38] <relaxed> bmuk: you're using the command directly from the guide, yes?
[06:39] <relaxed> which resolution are you actually using on your desktop?
[06:39] <relaxed> dantxo: how many /dev/video* device do you have?
[06:39] <bmuk> yes I am. My monitor is 1920x1080
[06:40] <relaxed> devices*
[06:40] <dantxo> 3, video0, video1 and video2
[06:40] <relaxed> what are the other two?
[06:40] <dantxo> video 1 and 2 are two webcams, and I want them to be always the same name under /dev/
[06:40] <relaxed> bmuk: ffmpeg -video_size 1920x1080 -framerate 25 -f x11grab -i :0.0 -c:v libx264 -preset:v veryfast output.mp4
[06:41] <dantxo> I've added a udev rule as suggested but it does not seem to work
[06:42] <bmuk> this is giving me 26 fps. Is processor just really slow?
[06:43] <dantxo> the rule that I've created for the first webcam is  SUBSYSTEM=="video4linux", BUS=="usb", SYSFS{idVendor}=="045e", SYSFS{idProduct}=="0761", NAME="video5"
[06:43] <relaxed> bmuk: lowering the "-framerate" should help
[06:43] <dantxo> for the second webcam SUBSYSTEM=="video4linux", BUS=="usb", SYSFS{idVendor}=="046d", SYSFS{idProduct}=="082b", NAME="video6"
[06:43] <dantxo> they are still named video1 and video2 under /dev/ after reboot though
[06:43] <bmuk> thank you relaxed.
[06:44] <relaxed> bmuk: You can also scale down the output. Try adding -filter:v scale=w=1280:h=-1 after the input.
[06:45] <bmuk> actually, I increased the framerate to 60 and it was much more usabel
[06:45] <bmuk> useable*
[06:53] <relaxed> dantxo: yeah, I don't know. maybe ask in your OS's channel
[07:43] <fundies> so no way to extract vobsubs from a mkv?
[08:30] <dantxo> how can I lower the picture quality of a webm stream? I'm over local network and the video is pretty slow, choppend, pretty bad overall
[09:25] <__raven_> klaxa: how to detect for (amount of) edges with result for scripts?
[09:31] <llogan> dantxo: http://trac.ffmpeg.org/wiki/vpxEncodingGuide
[09:40] <skinkitten_> hi everybody
[09:55] <goek> Hey I cannot get FFMPEG to connect to live stream could anyone help
[09:55] <goek> kk
[10:00] <goek> http://pastebin.com/adUrZCQZ
[10:00] <goek> fflogger
[10:00] <goek> llogan*
[10:00] <goek> It hangs at that spot
[10:02] <goek> it streams on justin.tv but not livestream oddly enough
[10:02] <goek> I think its because the documentation only allowed sometging like rtmp://server/live/stream
[10:03] <goek> and FFMPEG doesn't appear to support in URL RTMP authentication
[10:03] <goek> or I don't know how rather i'm sure its possible
[10:04] <goek> Has anyone here had success in streaming to livestream before?
[10:05] <llogan> goek: apparently http://ffmpeg.zeranoe.com/forum/viewtopic.php?f=7&t=657&start=50#p3063
[10:05] Action: llogan blames livestream
[10:06] <llogan> goek: i have to go now. try the ffmpeg-user mailing list if you don't figure it out. mayber there are other livestream users
[10:09] <goek> ok thanks
[10:31] <goek> exit
[14:00] <theTroy> Hi, I am trying to simply crop a video with ffmpeg, but it seems to also re-encode the whole video, is there a way to not do that?
[14:00] <theTroy> I am using crop filter*
[14:01] <saste> theTroy, no
[14:01] <JEEB> nope, cropping changes the video
[14:02] <JEEB> and thus you have to re-encode
[14:02] <JEEB> some formats have limited cropping flags in the header, but the cropping filter most definitely doesn't touch that, and you can't do major cropping with it anyways
[14:03] <theTroy> I only want to crop the video to 2/3 of the width, it uses default h264
[14:03] <theTroy> wouldn't want to re-encode it as cubie board will take ages doing that :(
[14:03] <JEEB> yeah, not gonna happen without re-encoding
[14:04] <theTroy> thats unfortunate, thanks for the help! :)
[14:14] <bencc> I'm getting "width not divisible by 2 (547x430)" when trying to convert a video from avi to mp4
[14:15] <bencc> can I ask ffmpeg to choose the closest even number for width and height?
[14:16] <saste> bencc, yes, use the scale filter, check examples
[14:16] <bencc> saste: thanks. searching
[14:20] <bencc> saste:  this seems to work: -vf scale='trunc(in_w/2)*2:trunc(in_h/2)*2'
[14:20] <bencc> hopfully I'm doing this right
[14:21] <saste> bencc, even better you can use the HSUB and VSUB variables, they will work also for other pix fmts than yuv420p
[14:22] <bencc> saste: I need mp4 to play on browsers
[14:22] <bencc> do HSUB and VSUB work on IE, Chrome, FF... ?
[15:07] <lkiesow> saste: About https://trac.ffmpeg.org/ticket/309
[15:07] <lkiesow> At that time your approved of the idea and said that patches are welcome. Noting happened since then.
[15:07] <lkiesow> Now I ran into the same problem and wrote a patch for that
[15:08] <lkiesow> Do you have any suggestions about what is the best way to contribute that patch to ffmpeg?
[15:08] <lkiesow> I found https://github.com/FFmpeg/FFmpeg
[15:08] <lkiesow> Is a pull request against that repo a good idea?
[15:12] <relaxed> lkiesow: http://www.ffmpeg.org/developer.html
[15:14] <lkiesow> Thanks, I will have a look at that
[16:17] <DelphiWorld> hi guys
[16:18] <DelphiWorld> please would someone give me a CPU aware ffmpeg command for H.264/AAC live streaming?
[16:18] <DelphiWorld> i'm using this:
[16:18] <DelphiWorld> ffmpeg -re -f mpegts -i udp://@239.100.1.3:1234 -vcodec h264 -b:v 600k -acodec libfdk_aac -b:a 64k -f flv -threads 8 -preset veryfast rtmp://localhost:1935/myapp/rtdoc
[16:41] <DelphiWorld> what's the best CPU friendly x264 presets?
[17:13] <lkiesow> DeadSix27: There should also be an ultrafast preset for x264 which should need even less CPU power
[17:26] <dantxo> Hello again
[17:27] <dantxo> I don't really understand what I'm doing wrong
[17:27] <dantxo> I'm streaming webm format video from my webcam, with a pretty low quality
[17:27] <dantxo> but the video gets stucked, and there is a huge delay
[17:27] <dantxo> audio & video are not in sync
[17:31] <dantxo> ffserver config: http://pastie.org/8666773
[17:31] <dantxo> ffmpeg streams: http://pastie.org/8666779
[17:32] <dantxo> The mjpeg stream is really smooth without delay
[17:32] <dantxo> but the webm stream is terrible (not in video quality, that I dont mind) but with a huge delay and audio out of sync
[17:55] <DelphiWorld> ffmpeg -re -f mpegts -i udp://@239.100.1.4:1234 -vcodec h264 -b:v 600k -pix_fmt yuv420p -acodec libfdk_aac -b:a 64k -f flv -r 25 -s 1920x1080 -threads 8 -preset veryfast rtmp://localhost:1935/myapp/yemen
[17:55] <DelphiWorld> :P
[18:03] <dantxo> DelphiWorld: is that for me?
[18:03] <DelphiWorld> dantxo: what was your question? :P
[18:04] <dantxo> how to speed up webm stream
[18:05] <DelphiWorld> ah i'm not sue
[18:05] <DelphiWorld> sure
[18:14] <relaxed> dantxo1: look at "ffmpeg -h encoder=libvpx"
[18:16] <DelphiWorld> llogan: alive?
[18:21] <shevy> got a question - the video with x11grab is kinda blurred. is there a way to have it much sharper?
[18:40] <dantxo1> By doing this ffmpeg -f v4l2 -s 320x240 -i /dev/videovx2000 http://localhost:8000/ext.ffm -f v4l2 -s 320x240 -i /dev/videoc170 http://localhost:8000/int.ffm
[18:40] <dantxo1> Shouldn't each webcam feed ext.mjpg and int.mjpg streams? I see the image from the same webcam in both streams
[19:04] <lkiesow> shevy: Which command did you use?
[19:05] <shevy> hmm
[19:05] <shevy> ffmpeg -f x11grab -video_size 1024x800 -r 25 -i :0.0 /Depot/Temp/GRABBED.mpg
[19:05] <shevy> may be related to .mpg default?
[19:12] <lkiesow> I guess so
[19:12] <lkiesow> Could you try: ffmpeg -f x11grab -video_size 1024x800 -r 25 -i :0.0 -c:v libx264 -preset ultrafast -qp 0 out.mp4
[19:13] <lkiesow> Though you probably don't want to use that for actual recordings (lossless h264)
[19:14] <shevy> yeah a moment
[19:15] <shevy> hmm Unrecognized option 'preset'.
[19:15] <shevy> Error splitting the argument list: Option not found
[19:18] <lkiesow> then just ignore preset for now
[19:30] <DelphiWorld> what's -r option do?
[19:34] <shevy> DelphiWorld, should be -video_frame_rate
[19:34] <shevy> probably sets how many frames there will be in a second
[19:35] <DelphiWorld> could be
[19:42] <DelphiWorld> shevy: if i give you a live stream, can you ffprobe it and tel me how to produce similar stream?
[19:43] <shevy> DelphiWorld but I have no experience with streams
[19:44] <DelphiWorld> yeah but is h264 regardless
[20:44] <shevy> llogan hmm?
[20:44] <llogan> it will show why preset is not found
[20:45] <shevy> I see
[20:45] <shevy> http://pastie.org/pastes/8667156/text
[20:46] <llogan> shevy: you have no libx264 support
[20:46] <llogan> no --enable-libx264
[21:03] <shevy> ok, recompiling right now with --enable-libx264
[21:12] <llogan> or you could use rawvideo (huge files), or a lossless encoder other than libx264 (huffyuv, utvideo, ffv1, etc) [big files], and then re-encode that when you are done capturing the screen
[21:15] <shevy> it worked now
[21:16] <xlinkz0> i'm trying to connect with ffmpeg to a broken rtsp server
[21:17] <xlinkz0> however it does not timeout or output anything, it just hangs
[21:17] <xlinkz0> this was the whole output : http://codepad.org/i7Q6Qg3P
[21:17] <llogan> xlinkz0: your command is missing
[21:17] <xlinkz0> sorry
[21:18] <xlinkz0> http://codepad.org/m2njeW3g
[21:18] <xlinkz0> i'd like to use ffmpeg to check when that server is up
[21:18] <xlinkz0> can i make it exit after some time if it doesn't receive anything from the server?
[21:19] <llogan> -timeout
[21:19] <llogan> http://ffmpeg.org/ffmpeg-protocols.html#rtsp
[21:20] <xlinkz0> thank you !
[22:47] <lkiesow> michaelni: Thanks for merging my patch in &and cleaning it up :)
[00:00] --- Sun Jan 26 2014