[Ffmpeg-devel-irc] ffmpeg.log.20131124

burek burek021 at gmail.com
Mon Nov 25 02:05:01 CET 2013


[06:00] <matador007> Hmm
[10:37] <Videogamer555> I've got a problem with FFMPEG. I'm trying to convert 10 single BMP frames into a ten second video clip at 30fps.
[10:39] <Videogamer555> The idea is that it will duplicate each frame 30 times so that it will run at a standard 30fps, but still last a whole 10 seconds (instead of 1/3rd of a second as would happen if you played 10 frames at 30fps).
[10:40] <Videogamer555> My input are raw image data (BMP files) and likewise the output video file should be a raw BGR24 AVI file.
[10:41] <Videogamer555> Each frame is labeled fx.bmp where the f is litteral, x is a number from 0 to 9, so the frames are f0.bmp to f9.bmp
[10:41] <Videogamer555> My command line is ffmpeg.exe -f image2 -r 1 -i f%%01d.bmp -pix_fmt bgr24 -f avi -vcodec rawvideo -r 30 video.avi
[10:41] <Videogamer555> -f image2 tells it that the input will be images
[10:42] <Videogamer555> -r 1 tells it that it should consider the input frames to be at a framrate of 1fps.
[10:43] <Videogamer555> -i f%%01d.bmp means the filename starts with a literal f letter, %% is to a batch file the same as % is to directly typing in the command line, and 0 is padding char and 1d means it is one digit and .bmp is literal.
[10:44] <viric> Videogamer555: the manpage has an example for that, isn't it?
[10:44] <Videogamer555> Then the output pixel format is specified, the output file format and output codec being raw image data, and the intended playback rate is 30fps.
[10:44] <Videogamer555> BUt there's one problem.
[10:44] <Videogamer555> It doesn't work.
[10:45] <Videogamer555> It SHOULD duplicate the frames as needed, but it doesn't.
[10:45] <Videogamer555> Instead it uses duplicate AVI index entries to refer to the same frame, as needed.
[10:45] <Videogamer555> But Windows Media Player doesn't recognize this technique.
[10:45] <Videogamer555> And it expects one frame for each index in the AVI file.
[10:46] <Videogamer555> So it refuses to play it, though VLC player plays it fine.
[10:46] <Videogamer555> Is there a way to force FFMPEG to produce duplicate frames, and NOT just duplicate index entries?
[10:46] <viric> ah no idea
[10:47] <beastd> Videogamer555: what happens if you use http://ffmpeg.org/ffmpeg-all.html#fps-1
[10:48] <Videogamer555> Virtualdub works correctly using this technique, and as far a I know it uses FFMPEG as the engine behind it all. But FFMPEG is a bulky program that has tons of features that I'm not using, with lots of buttons, and a simple command line in a bat file is much nicer and smaller for such a simple task.
[10:49] <Videogamer555> Is this "fps" command a filter name, or a new direct command?
[10:50] <beastd> Videogamer555: it is a filter name. you could use it instead of the -r at the output file likw with -vf fps=fps=30
[10:50] <Videogamer555> I meant VDUB is a bit bulky, but FFMPEG is smaller so is more desirable.
[10:51] <Videogamer555> By the way why should I have to use a filter, if there is already a native FFMPEG command? Seems like the native command is brokern.
[10:51] <Videogamer555> *broken.
[10:51] <Videogamer555> Also isn't the proper filter command -vf fps=30 ?
[10:52] <Videogamer555> Why did you have it like -vf fps=fps=30 with the fps= in there twice?
[10:54] <Videogamer555> Seems like the output is still incompatible with WMP even though I'm now using the filter (though now the frames are being properly duplicated).
[10:55] <Videogamer555> Is it a known problem that FFMPEG's output is incompatible with Windows XP's version of WMPlayer? I think it worked fine in Windows 7 WMPlayer, but now I'm using a WinXP comp and there's a problem. What's going on.
[10:55] <Videogamer555> ?
[10:58] <Videogamer555> And still a bug with getting the last frame right. It doesn't duplicate the last of the 10 frames, so the last frame flashes on the screen for 1/30th of a second, even in VLC player. I don't know who makes FFMPEG, but it seems there program is full of bugs, especially bugs near end of video (last frame errors).
[11:04] <beastd> I was away for 10 minutes and now Videogamer555 is gone.
[11:11] <relaxed> beastd: "Ain't nobody got time for that"
[11:14] <beastd> :9
[11:14] <beastd> :)
[14:02] <cian1500ww> Hi guys, I'm having problems killing an ffmpeg process invoked with the python subprocess module. When I kill from the process from the command line I get the following output: http://paste.ubuntu.com/6468480/ but when I kill it from with python with os.kill() I get the following output: http://paste.ubuntu.com/6468477/ It doesn't exit cleanly and leaves behind a corrupt video file. Any ideas why this
[14:02] <cian1500ww> happening?
[14:04] <cian1500ww> So, os.kill(ffmpeg.pid) gives me: http://paste.ubuntu.com/6468480/ where as "$ kill ffmpeg.pid" gives me: http://paste.ubuntu.com/6468477/
[14:15] <Samus_Aran> anyone know how timestamps work if you cut a segment from a video, then apply a filter like fade in.  will the fade in be applied to the original whole video length, or to the cut segment?
[19:17] <CaptainAmerica> hi
[19:18] <CaptainAmerica> is it there a way to use opengl game as a live source ?
[19:18] <klaxa> i think there was a project aiming exactly at that
[19:18] <klaxa> it wasn't ffmpeg though
[19:19] <CaptainAmerica> oh... no i wanted to do it with ffmeg i thought may some plugin was available
[19:20] <sacarasc> Does X capturing not work for it?
[19:20] <klaxa> you can use x11grab to gram from X
[19:20] <klaxa> yeah
[19:22] <CaptainAmerica> x11grab is a ffmpeg plugin ?
[19:22] <klaxa> it's an input format
[19:23] <CaptainAmerica> hmmm thanks i'll try to find some info about it
[19:23] <klaxa> CaptainAmerica: https://its.ffmpeg.org/wiki/How%20to%20grab%20the%20desktop%20%28screen%29%20with%20FFmpeg
[19:23] <klaxa> args
[19:28] <ss_haze> hello everyone using ffmpeg
[19:29] <ss_haze> ffmpeg -i file.mov -ab 56 -ar 44100 -b 200 -r 15 -s 1280x720 -f flv file.flv
[19:29] <ss_haze> I'm using this
[19:29] <ss_haze> but it gives low res
[19:29] <ss_haze> how do I get best quality convert
[19:29] <ss_haze> sacarasc, I'm doing this via php
[19:30] <ss_haze> should I dump
[19:30] <sacarasc> You should run the command and give the output!
[19:30] <ss_haze> can I just keep orginal framerate quality and stuff
[19:34] <klaxa> quality is subjective
[19:34] <sacarasc> So, it's not about resolution, but about quality?
[19:35] <sacarasc> Use a better coded.
[19:35] <sacarasc> *codec
[19:35] <sacarasc> Use a higher than 200 bits per second bitrate.
[19:35] <sacarasc> (If you don't have it as 200k, it will be just 200.)
[19:37] <ss_haze> res could also stay the same
[19:37] <ss_haze> I just need other format for h264 vid to go in firefox
[19:37] <klaxa> vp8 in webm
[19:37] <ss_haze> yes
[19:37] <klaxa> ffmpeg -i video.mkv out.webm
[19:38] <klaxa> that should set everything you need
[19:38] <sacarasc> I thought firefox did H264 these days, at least on Windows?
[19:38] <klaxa> since webm is so restricted
[20:00] <bio-tty> is there a program like sox, that can dump the filter it has designed from my specification?
[20:00] <bio-tty> let's say i provide parameters for sox to apply a highpass filter.  and then i want the A array for a FIR filter, that i can import in another tool.
[20:08] <ss_haze> this does nothing
[20:08] <ss_haze> ffmpeg -i ".$file_path." -vcodec copy -acodec copy -y webm ".$file_path2."
[20:09] <klaxa> no no no
[20:09] <klaxa> don't copy the audio and video codec
[20:09] <LithosLaptop2> if the source doesn't contain Vorbis/Opus + VP8/VP9 video then it wont work
[20:23] <ss_haze> ffmpeg -i ".$file_path." ".$file_path3."
[20:23] <ss_haze> this gives me corrupt file
[20:23] <ss_haze> ffmpeg -i ".$file_path." ".$file_path2." and this gives webm file with bad quality
[20:28] <ss_haze> .flv is corrupt
[20:28] <ss_haze> and .webm is bad
[20:28] <ss_haze> so why
[20:28] <ss_haze> ?
[20:29] <klaxa> paste ffmpeg --version
[20:29] <klaxa> and you can crank up the quantiziers for webm
[20:30] <klaxa> or rather vp8/vp9
[20:34] <lvella> I've read somewhere that codec rv40 is similar to h264, so I am wondering, wouldn't it be possible transform a rv40 stream into a h264 stream on the fly, to take advantage of h264 decoding hardware?
[20:35] <klaxa> i doubt it
[20:35] <klaxa> windows video codec 9 is similar to h264 too afaik
[20:35] <klaxa> vp8 is "similar" too
[20:35] <klaxa> you could re-encode on the fly
[20:36] <klaxa> depending on the video you will need quite a powerful cpu though
[20:36] <klaxa> but then you can just use the cpu to decode
[20:37] <lvella> the device I want to play it has a very weak CPU, but has also a x264 hardware decoder
[20:38] <klaxa> *h264
[20:38] <ss_haze> 0.6.0-svn
[20:39] <ss_haze> ffmpeg version 0.8.9-4:0.8.9-0ubuntu0.12.04.1
[20:39] <klaxa> oh... ogd...
[20:39] <klaxa> *god
[20:40] <klaxa> that's old
[20:43] <ss_haze> how do I get newer \
[20:43] <ss_haze> I use ubuntu LTS
[20:43] <klaxa> compile from source or get a static build
[20:43] <klaxa> or don't use ubuntu LTS
[20:44] <klaxa> but i guess that's out of question
[20:44] <ss_haze> why would ffmpeg -i ".$file_path." ".$file_path3."
[20:44] <ss_haze> give bad output
[20:44] <ss_haze> anyway
[20:45] <klaxa> because we don't even know what those variables expand to
[20:45] <klaxa> the filename ending of the output parameter determines what codecs are used by default
[20:46] <ss_haze> file paths
[20:46] <ss_haze> images/video/randomnumber.mov
[20:46] <ss_haze> images/video/randomnumber.webm
[20:47] <ss_haze> atleast
[20:47] <ss_haze> ffmpeg -y -i ".$file_path." -vframes 1 -ss 00:01:60 -an -vcodec png -f rawvideo -s 1280x720 ".$png_path4."
[20:47] <klaxa> it will be a) because your ffmpeg is old and 2) you should specify more parameters determining quality, e.g. -ab 96k -vb 700k or something
[20:47] <ss_haze> this gives screenshot
[20:48] <ss_haze> then give me arguments for best quality
[20:48] <ss_haze> flv is corrupted and contains no data
[20:48] <ss_haze> omg
[20:50] <klaxa> you should seriously update your ffmpeg
[20:51] <ss_haze> repo
[20:51] <ss_haze> pls
[20:52] <ss_haze> ppa:jon-severinsson/ffmpeg
[20:59] <ss_haze> ffmpeg version 0.10.9-7:0.10.9-1~precise1
[20:59] <ss_haze> now I have
[21:02] <ss_haze> webm still is bad
[21:02] <ss_haze> and flv contains no stream
[21:15] <ss_haze> http://paste.ubuntu.com/6470488/
[21:15] <ss_haze> as you can see
[21:21] <ss_haze> https://phpacademy.org/topics/convert-uploaded-videos-to-flash-and-webm-video-types-adding-that-to-database/31267#165286
[21:21] <ss_haze> ok here is the full post
[21:21] <ss_haze> if anybody wants to check full code
[21:22] <ss_haze> on this
[21:48] <ss_haze> so
[21:48] <ss_haze> nobody knows why it happens like that?
[21:50] <ss_haze> http://paste.ubuntu.com/6470676/
[21:50] <ss_haze> this what happens in terminal
[21:53] <ss_haze> http://paste.ubuntu.com/6470687/
[21:53] <ss_haze> this is what happens with webm convertation
[22:13] <ss_haze> I got something with adding some arguments in that line
[22:13] <ss_haze> flv still in making
[23:58] <cbsrobot> ss_haze: if you want to encore to webm consider reading: https://trac.ffmpeg.org/wiki/vpxEncodingGuide
[23:59] <ss_haze> cbsrobot, I already got trought my problem
[23:59] <ss_haze> thanks anyway
[23:59] <cbsrobot> ok, and flv nowadays supports h264 in flv
[00:00] --- Mon Nov 25 2013


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