[Ffmpeg-devel-irc] ffmpeg.log.20131117

burek burek021 at gmail.com
Mon Nov 18 02:05:01 CET 2013


[00:08] <pyBlob> and is it possible for ffplay to display 2 video-streams at the same time that were created from a video filter?
[00:09] <Samus_Aran> pyBlob: display two how?  you could load two player, I suppose
[00:09] <pyBlob> ... for 3d-avis ffplay opens 2 windows, because there are 2 video streams
[00:09] <Samus_Aran> didn't know you were doing 3D
[00:10] <pyBlob> but I can't make it open two windows when the video filter has 2 outputs
[00:10] <pyBlob> (but only 1 input)
[00:11] <pyBlob> so currently I'm not using a 3d-video
[00:12] <Samus_Aran> not related to 3D, but you can overlay one video on another
[00:12] <Samus_Aran> you could put them side-by-side if that's your goal
[00:12] <pyBlob> yes ... that would be possible
[00:12] <Samus_Aran> for the colour-space conversion, use -pix_fmt
[00:13] <Samus_Aran> before the output file, if you're trying to change it
[00:13] <pyBlob> I need it in the video-filter
[00:15] <Samus_Aran> so try putting it before that
[00:16] <Samus_Aran> -pix_fmt rgb24
[00:16] <Samus_Aran> is probably what you want, not sure
[00:22] <pyBlob> no, that doesn't work :/
[00:22] <pyBlob> it has to be something inside the filter
[00:26] <pyBlob> I've tried "format=pix_fmts=rgb24,split[a][b];..." but it doesn't work
[00:27] <Samus_Aran> I'm not sure what to suggest, I've barely touched filters.  maybe someone else can help
[00:49] <pyBlob> yay, crashed ffmpeg xD
[00:51] <pyBlob> because ffmepg mapped a video stream into an audio stream =)
[01:30] <Samus_Aran> pyBlob: how did you manage to do that?
[01:31] <pyBlob> putting -map 0:a after -lavfi "..."
[01:31] <pyBlob> when putting the map before the filter everything is fine ._.
[01:36] <Samus_Aran> and that crashes ffmpeg, or just doesn't work as expected?
[01:37] <pyBlob> it crashes ffmpeg
[02:16] <Samus_Aran> lol @ this error: scale/rate is 1/0 which is invalid. (This file has been generated by broken software.)
[02:16] <Samus_Aran> it was generated by ffmpeg
[02:17] <Samus_Aran> ffmpeg seems incapable of cutting clips from an AAC/PCM Matroska file without completely ruining the internal time keeping
[02:17] <Samus_Aran> er, AVC+PCM
[02:18] <Samus_Aran> previously it gives lots of these errors: Non-monotonous DTS in output stream
[02:31] <Samus_Aran> the problem has something to do with ffmpeg converting .ts to .mkv, because if I try to cut segments from the original .ts it works without timing errors
[02:48] <t4nk218> <-- Running Ubuntu 13.10...can't get ffmpeg to capture video despite the codec.
[02:48] <t4nk218> ffmpeg -f x11grab -r 25 -s 1920x1200 -i :0.0 -sameq /home/ken/Desktop/test.mp4
[02:49] <t4nk218> it successfully saves the file, just doesn't have any video.
[02:49] <t4nk218> please tell me there is something wrong with the Ubuntu 13.10 ffmpeg default package and that a MAKE or something like that will fix it.
[02:52] <JEEB> t4nk218, if you want to use the stuff that comes with ubuntu you should use the 'avconv' command
[02:52] <JEEB> since ubuntu uses the libav fork, and not ffmpeg as the project
[03:11] <t4nk218> JEEB, thank you. I got the same result with the avconv command. I'm not getting any errors. Could there be an issue with x11grab?
[03:12] <JEEB> no idea, also libav problems should generally go to #libav :)
[03:13] <t4nk218> will do..thx
[04:45] <annath> Hey all. I'm trying to grab a single image from a webcam connected to a beaglebone via USB, but whenever I run the command it just kind of stops and never finishes. Here is the command I am running and the output: http://pastebin.com/nzjGCdqX Does anyone have any ideas what might be causing this?
[04:46] <annath> I've left it for a few minutes there waiting for it to complete but it never does. Also, the light on the webcam turns on like it's in use.
[05:02] <buu> annath: Uh, stop using avconv and use ffmpeg?
[05:03] <buu> And have you verified you can read anything from that device? Are you sure its the correct device? What does strace say?
[05:04] <buu> In otherwords what makes you think this is related to ffmpeg?
[05:58] <davo> which ffmpeg version contained av_open_input_file function?
[05:58] <davo> (if that's even a valid question)
[05:59] <davo> i'm trying to build a package that needs an older version, ~0.5 - ~1.10 i think
[05:59] <davo> er, 0.10 not sure
[11:50] <ArtemMakhutov> Hi, I have a question about PTS/DTS in H264:
[11:50] <ArtemMakhutov> I am trying to mux a raw H264 stream to a TS container. This fails with an error that the H264 stream does not contain PTS/DTS. But muxing the same stream to MKV everything works fine. Later this MKV can be reused to MUX from it to TS.
[11:50] <ArtemMakhutov> Is the MKV container not using PTS/DTS? Or is this getting calculated in MKV? Why is it not possible to directly mux to TS?
[12:13] <tremon> hi all, what's the most straightforward way to determine the framesize in a video file? Right now I'm using awk to parse the output of avconv -i, but I'm hoping there's a better way
[12:28] <relaxed> tremon: avconv is from the #libav project. I would use awk with avprobe.
[12:28] <tremon> ah, thanks. Didn't know the two projects were separate
[12:36] <ubitux> tremon: note that ffprobe has more output formats
[12:39] <tremon> thanks, I'll read up on it
[12:43] <ubitux> tremon: stream specifier are available in ffprobe
[12:44] <ubitux> tremon: http://ffmpeg.org/ffprobe.html#Stream-specifiers-1
[12:44] <ubitux> -select_streams
[12:45] <tremon> lol. It doesn't reduce the confusion if questions in the one channel are answered in the other ;)
[12:45] <tremon> but thanks anyway
[12:45] <ubitux> i can't answer on #libav
[12:45] <ubitux> i'm an evil being from the evil project
[12:45] <relaxed> would it be considered poaching?
[12:46] <ubitux> i'm sorry for helping users
[12:47] <ubitux> tremon:
[12:47] <ubitux> - ./ffprobe -v error -select_streams v:0 -of flat -show_entries stream=width,height ~/samples/matrixbench_mpeg2.mpg
[12:47] <ubitux> streams.stream.0.width=720
[12:47] <ubitux> streams.stream.0.height=576
[12:48] <ubitux> i think this is what you are looking for
[12:48] <ubitux> note that avprobe lacks at least 3 of the features i'm showing here
[12:48] <ubitux> (stream selection, flat output, and entries filtering)
[12:48] <tremon> yes, it is
[13:17] <technocf> I'm having an issue with cracking using this script, http://pastebin.com/Dc5Ncdw3, and streaming to twitch with this one, http://pastebin.com/0Vux2WG4, I dont know where the issue is.
[13:18] <technocf> Audio crackiling
[13:18] <technocf> Also video is flashy
[13:30] <technocf> I think my audio problems are to do with ffmpeg as the audio starts out good and progressively gets worse
[13:32] <technocf> Is there even anyone active here?
[13:33] <relaxed> -qscale 5 does nothing there
[13:33] <technocf> I just copied a "perfectly working" script
[13:33] <technocf> I dont do much with ffmpeg
[13:33] <relaxed> I see that script at least once every two weeks
[13:34] <technocf> We need a propper streaming solution, but this is all we have for now.. :/
[13:34] <relaxed> what version of ffmpeg are you using?
[13:34] <technocf> ffmpeg -v ?
[13:35] <technocf> ffmpeg version 0.8.9-6:0.8.9-0ubuntu0.13.10.1, Copyright (c) 2000-2013 the Libav developers
[13:35] <technocf> from apt
[13:35] <relaxed> ok, that is from the libav project and it's very old to boot.
[13:35] <technocf> apparenly its depricated, yeah
[13:36] <relaxed> well, their focus is on avconv
[13:36] <technocf> E: Unable to locate package avconv
[13:36] <relaxed> it's probably already installed.
[13:36] <technocf> It is -derp-
[13:37] <relaxed> You need to download the latest ffmpeg source and compile it with the support you need.
[13:37] <technocf> Unrecognized option 'vpre' Failed to set value 'fast' for option 'vpre'
[13:37] <technocf> Getting that now
[13:37] <relaxed> https://trac.ffmpeg.org/wiki/UbuntuCompilationGuide
[13:37] <relaxed> follow that ^^
[13:38] <technocf> I tried to install it that way actually, I remember now.... Well I tried to but I could not for the life of me get it to compile compying it word for word so I used apt
[13:39] <technocf> copying*
[13:39] <relaxed> try again, I'll help if you run into an issue
[13:39] <technocf> ok
[13:41] <technocf> YASM installed fine
[13:43] <relaxed> ubitux: how do you list which indevs an ffmpeg binary was compiled with?
[13:44] <ubitux> -formats probably
[13:45] <technocf> I did do: "sudo apt-get update; sudo apt-get upgrade" since I last tried
[14:21] <technocf> The compile was successgul
[16:15] <slorbast> Question about command line piping when using ffmpeg to chop a video up into images: Current command: http://pastebin.com/BDAjxUTU
[16:17] <slorbast> My goal is to use livestreamer to get stream data, ffmpeg that stream into images that can be converted and do some image to text recognition on that all in one command instead of doing two separate
[16:18] <slorbast> I'd like to just feed the image data into imagemagick, but not sure how to pipe that using those options with ffmpeg. Will I need to use like a python script to look for EOF to separate out images?
[17:03] <vl4kn0> Hi, when using buffersink filter in a code, in the doc/examples there is AVBufferSinkParams structure used as a opaque parameter to avfilter_graph_create_filter. The only field that is set on that structure is pixel_fmts set to { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE }. Is this argument required? What is it used for? Can I skip it and gain therefore support for every every pixel format?
[22:21] <sly007> Why can't I join #ffmpeg-devel?
[00:00] --- Mon Nov 18 2013


More information about the Ffmpeg-devel-irc mailing list