[Ffmpeg-devel-irc] ffmpeg.log.20140211

[burek]

[00:12] <Guest68016> Hello, is it possible to stream my desktop live via http?
[04:20] <z1lt0id> I'm writing a bash script and I want to a dummy encode of an aac file to see what bitrate it would turn out to be.  Is there a way to write the information to a text file of the overall bitrate with ffmpeg?
[04:21] <ezekiel> z1lt0id: ffprobe
[04:22] <ezekiel> and/or use -stats output during encoding
[04:24] <z1lt0id> ill check out the command thanks :)
[07:42] <Logicgate> hey guys
[07:42] <Logicgate> I need to install ffmpeg properly
[07:43] <Logicgate> I had a hell of a time last time doing it
[07:43] <Logicgate> any good tutorials for CentOS
[09:30] <superware> I'm building a video player for live streams with libav*, how should I sync the frames for display? does it matter that the stream is live and packets can't "come early"?
[09:33] <luc4> Hello! I wrote some code to mux a h264 stream in avcc format into mp4 using annex b with ffmpeg. I parse the stream for the various nal types (0x65, 0x61, 0x68, 0x67 etc...), I create the annex b and I use ffmpeg to mux. Now I just encountered a stream that has none of these nal formats but types like 0x27 and 0x21. Anyone who knows what these nals are and how I should give them to ffmpeg?
[09:36] <superware> or... how should I sync a live video stream I'm getting from libav?
[09:46] <superware> I have a decoding thread and a playback thread, should I queue packets or frames in the decoding thread?
[10:46] <luc4> Hello! Can I somehow mux a rtp h264 stream into an mp4 using ffmpeg?
[11:14] <cyberef> is there anyway to determine the actual duration of a video-file that is not complete? Like for example if you aborted the upload of it in a FTP-transfer
[11:16] <Keestu> Dear all, are they any ported file of ffplay.c for SDL2.0 ?
[11:57] <excalibr> How do you achieve the same effect as adding opt --engage no_cue_duration,no_cue_relative_position in mkvmerge?
[14:27] <vak> hi
[14:27] <vak> are the avconv questions appropriate to be asked here?
[14:28] <spaam> #libav is a better place.
[14:28] <vak> thanks!
[14:38] <DelphiWorld> hi FFmpeg's
[14:39] <DelphiWorld> ffmpeg -f mpegts -i http://172.16.32.100:8081/bysid/12 -deinterlace -vcodec libx264 -vb 256k -acodec libfdk_aac -ab 48k -ar 44100 -f flv rtmp://myRTMPD:1935/myapp/MyTV
[14:39] <DelphiWorld> is working *perfectly*
[14:40] <DelphiWorld> except of sometime it's get down
[14:40] <DelphiWorld> i dont know why
[14:41] <relaxed> Logicgate: http://johnvansickle.com/ffmpeg/
[14:43] <relaxed> DelphiWorld: this has nothing to do with your issue, but instead of "-deinterlace" use "-vf yadif".
[14:44] <DelphiWorld> relaxed: hehe, first time i heard about it. can you give a clue about it or the diference?
[14:45] <DelphiWorld> relaxed, also is my settings is acceptable for that kind of streaming?
[14:48] <DelphiWorld> changed:)
[14:49] <relaxed> -vf yadif is a much better deinterlacer
[14:50] <DelphiWorld> relaxed: just the naming made me  laugh a bit
[14:50] <DelphiWorld> ok so what about the other params, are they good for live encoding?
[14:50] <relaxed> DelphiWorld: Have you read https://trac.ffmpeg.org/wiki/StreamingGuide ?
[14:51] <DelphiWorld> relaxed: a lot, but streaming & transcoding are not the same:-P
[14:53] <relaxed> well, there's a section entitled "Transcoding/repeating"
[14:54] <DelphiWorld> relaxed: i'm allready on it:-)
[15:27] <DelphiWorld> the ffmpeg is still auto shutting down!
[15:45] <DelphiWorld> [mpeg2video @ 0x3164560] 00 motion_type at 22 26
[15:45] <DelphiWorld> Clue less lol
[17:58] <hexhaxtron> Hello! I'm using this command: for filename in *; do ffmpeg -loop 1 -r 2 -i rise.png -i "$filename" -c:v libx264 -preset medium -tune stillimage -crf 18 -c:a copy -shortest -pix_fmt yuv420p "$filename".mkv; done
[17:58] <hexhaxtron> And I get: Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[17:58] <hexhaxtron> What should I do?
[17:58] <hexhaxtron> Is it the picture size?
[18:33] <bmhm> Hi all. I'm getting invalid frame sizes which make ffmpeg and afterwards ffserver crash. Please see: http://pastebin.com/aSqEzkqP
[18:35] <bmhm> wrong paste, see http://pastebin.com/gxncpZQx
[18:50] <bmhm> Wow, the shipped USB cable is bad.
[19:05] <bmhm> What does ffserver's StartSendOnKey do?
[19:55] <ramin> hey I try to concat two videos. I have absolute paths in the required text file, but he ffmpeg doesnt get it says then of course that the file do not exist (folder of the txt file+absolutepath)
[19:56] <rafajafar> hey I was wondering, is it possible to remove the black borders from a video using ffmpeg? When I do crop detect it's frame by frame. Anyone know of a fast way to just accept crop detects suggestion and then scale to a size?
[19:56] <ramin> one entry looks like this file 'C:/davideocliper/data/input/video/rendered/idO07rk5YVY/scene-1.avi'
[20:30] <bmhm> rafajafar: ffmpeg -i input.mp4 -vf crop=1280:700 -y output.mp4
[20:33] <rafajafar> yeah but I want to auto detect black borders and get rid of them, then resize the video to be normalized
[20:34] <rafajafar> cropdetect filter is pretty straight-on, but it only tells me what needs to be cropped, it doesn't actually do the cropping... was wondering if there's a single command, or maybe two, that will let me crop and then resize an entire video
[20:38] <rafajafar> thanks, though, bmhm
[20:39] <Mavrik> rafajafar, I don't think so
[20:39] <Mavrik> several reasons really :)
[20:40] <rafajafar> it appears crop detect works frame by frame, for one, so if it detects two different values per frame it would throw off the enitre video resolution
[20:41] <rafajafar> still would prefer an average crop or even a chain command where frame by frame is crops and THEN resizes
[20:41] <rafajafar> just trying to normalize the video for computer vision work
[20:41] <Mavrik> rafajafar, yeah, the thing is that ffmpeg filters don't really have info about context, they can only process frame by frame
[20:42] <Mavrik> so cropdetect can't really tell you an "averate" crop rectangle, only rectangle for current frame
[20:42] <Mavrik> which can differ wildly (e.g. you can have all-black frames with text in it)
[20:42] <Mavrik> that's why it can't do processing online as well - you're not allowed to change video resolution inside stream
[20:42] <rafajafar> right, so I definitely wish I could detect->crop->resize each frame in one step
[20:42] <Mavrik> yeah but you cant because frames have to be exact same size :)
[20:42] <rafajafar> hence the resize
[20:44] <rafajafar> this would speed things up immensely if ffmpeg had a way to do it rather than relying on my homebrew border detection algorithm and openCV
[20:44] <rafajafar> c'est la vie
[21:18] <jangle> what format does ffmpeg expect audio data like g.711 frames to be, or in other words, is there an equivalent to h264 annex b for g.711 audio?
[22:14] <guthead> can ffmpeg take a still frame image and zoom in and pan around and generate a video, or do I need to use something like imagemagick to actually generate the frames first and feed them into ffmpeg?
[22:22] <llogan> guthead: yes, ffmpeg can probably do that with various filters and expressions
[00:00] --- Wed Feb 12 2014