[Ffmpeg-devel-irc] ffmpeg.log.20130115

burek burek021 at gmail.com
Wed Jan 16 02:05:01 CET 2013


[00:09] <Sashmo_> some told me that there is some C library out there that can do very good PAL-NTSC conversion, but I dont have a name, anyone know anything about it?
[01:05] <Fedcomp> hi guys
[01:05] <Fedcomp> can i ask?
[01:05] <klaxa> always
[01:05] <Fedcomp> i have PC computer with Intel Core i3, and linux machine with core 2 duo
[01:06] <Fedcomp> i want to stream. But xsplit gives me ugly quality on my pc, so i want to use linux machine as encoding
[01:06] <Fedcomp> does pc:ffmpeg to linux:crtmpserver+ffmpeg to stream to twitch any better than ffsplit?
[01:07] <Fedcomp> worth to try?
[01:07] <klaxa> worth to try? probably, it's an interesting setup and not trivial
[01:07] <Fedcomp> it's not that hard to setup, i have some knowledge and almost done with crtmpserver
[01:08] <klaxa> linux machine with core 2 duo might be a bit weak for live-encoding, depending on the content
[01:08] <Fedcomp> can ffmpeg grab opengl/directx video directly?
[01:08] <klaxa> you could let ffmpeg stream over udp throughout the network and let it grab that stream on the linux machine
[01:08] <Fedcomp> well, i agree, but it's better than capture from screen, encode, send
[01:08] <Fedcomp> hmm interesting advice.
[01:09] <klaxa> since using rtmp involves using udp anyways, it might reduce overhead
[01:09] <Fedcomp> got that. can ffmpeg grab opengl/directx video directly?
[01:09] <Fedcomp> i haven't found answer for this anywhere.
[01:09] <klaxa> http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20grab%20the%20desktop%20%28screen%29%20with%20FFmpeg
[01:09] <klaxa> i doubt it can
[01:09] <Fedcomp> it's not desktop, it's a game :3
[01:09] <saste> Fedcomp, it can't, support X11 grabbing though
[01:10] <Fedcomp> okay ty.
[01:10] <Fedcomp> using windows for now due to bad games support on linux.
[01:10] <saste> and watches pelcome
[01:10] <Fedcomp> is it planned? or you don't consider it?
[01:10] <Fedcomp> i mean opengl/directx grabbing
[01:10] <saste> Fedcomp, create a ticket and we'll see
[01:11] <saste> no opengl expertise here
[01:11] <Fedcomp> okay
[01:11] <Fedcomp> sorry no time to make ticket, but thanks for answers.
[09:35] <dott_infernus> Hi, I was here, yesterday...I need some help
[10:43] <EricAhn> are there any "VideoCodec vcopy" in ffserver.conf? I reviewed the ffserver.c but, I can't found. But, It have the feature in ffmpeg.
[10:44] <EricAhn> are there any reason that does not support copying video/audio data into ffserver (ffm)?
[10:45] <EricAhn> It doesn't think that far.
[10:45] <EricAhn> ?
[11:24] <dott_infernus> Hi. guys...I'm trying to use ffmpeg libraries on Qt... It gives me undefined reference when I try to call some function inside libraries...what I have to write into .pro file?
[12:01] <viric> umh
[12:01] <viric> I've used "-t 11400" encoding from video4linux2
[12:01] <viric> And after 3h40m of video, it was still encoding
[12:35] <dott_infernus> Hi, is there anyone?
[13:02] <dott_infernus> Guys, could someone help me with this-> http://pastebin.com/X9u52xDs
[13:02] <dott_infernus> This problem with ffmpeg is trying to kill my life
[13:02] <dott_infernus> afk
[13:04] <cbsrobot> dott_infernus: shouldnt the include path just be /usr/local/include ?
[13:11] <saste> dott_infernus, please use pkg-config
[13:11] <saste> check doc/example/Makefile to see how to integrate ffmpeg libs into your projects
[13:28] <Podium> Hello all!  Does anyone know something about color-shift in the contrast/saturation ?? This happends here when I try to transcode a ProRes (yuv422p10le) file to a libx264 (yuv420p) file...
[13:31] <Mavrik> define color shift
[13:31] <Mavrik> but yes, you'll lose some color information when doing that
[13:32] <Podium> Hi Mavrik! White becomes gray.... Grass greens becomes gray/green...
[13:32] <Podium> It's just a little... But it's really a little to much
[13:33] <Mavrik> hmmm
[13:33] <Mavrik> that sounds excessive (usually only reds become duller)
[13:35] <Podium> So it's logical color changes a bit... (I can image) but is there maybe a "default" color correction preset?
[13:36] <Mavrik> Podium, there's the colormatrix parameter for libx264 which specifies the color conversion matrix: http://mewiki.project357.com/wiki/X264_Settings#colormatrix
[13:36] <Mavrik> I've found that it sometimes fixes the problems
[13:36] <Mavrik> try setting different color matrices with -x264opts
[13:48] <Podium> Thx... I don't know yet if its a solution. But I see to colormatrix's (smpte170m & smpte240m) who look familair!
[13:48] <Podium> And about my audio problem yesterday...
[13:49] <Podium> I now first export the audio with ffmpeg, than delete the 14 channels with sox and than again import it with ffmpeg and the other video filters....
[13:55] <pacior> hello i am compiling ffmpeg from source on linux mint using toolchain and during script i have problem with configure script. it writes: arm-linux-androideabi-gcc is unable to create an executable file.
[13:55] <pacior> C compiler test failed.
[13:55] <pacior> i've got this messages in log: Assembler messages:
[13:55] <pacior> Fatal error: invalid -march= option: `armv7-a'
[13:55] <pacior> /tmp/ffconf.cSR9QYsG.c:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
[13:55] <pacior> C compiler test failed.
[13:55] <pacior> please help
[13:58] <viric> add -marm
[13:58] <viric> (if you don't want to generate thumb)
[13:58] <viric> and, are you sure you want armv7-a?
[14:03] <pacior> no i want really my app compatible with most of processors
[14:03] <pacior> so armv6 is ok?
[14:03] <pacior> and big thanks:)
[14:13] <pacior> thank you for previous answer, but i've got now missing argument to -mcpu error
[14:19] <viric> so it's clear, no?
[14:23] <pacior> not yet, can i find this in toolchain docs?
[14:24] <pacior> i have one question - if most android devices now are arm-based, mean nexus 7, galaxy ace etc
[14:25] <pacior> my problem starts when capture frames library starts with api level 10 since i need api level 8 for my app
[14:37] <viric> no idea about mobile phones.
[14:37] <viric> or non-GNU/linux
[15:01] <pacior> ok, thx
[15:09] <DonGnom> is there any way to convert a side-by-side 3D video to non 3D (i.e. dropping one side)?
[15:14] <pacior> viric: it's idea to compile it on android since it's kernel is linux-based
[15:15] <viric> that's why I said GNU
[15:48] <Abhijit> hi
[15:48] <Abhijit> anyone familiar with libavg coding?
[15:49] <Abhijit> i need to program libavt to use vaapi. and libavg uses ffmpeg to do the actual encoding/decoding. so how can i make ffmpeg enable to use vaapi?
[15:49] <Abhijit> help please
[21:14] <dott_infernus> Hello there...
[21:15] <dott_infernus> I need some help
[21:20] <stqn> who doesnt
[21:20] <stqn> ;)
[21:21] <dott_infernus> stqn
[21:22] <dott_infernus> may I ask you?
[21:22] <durandal11707> just ask
[21:25] <dott_infernus> I've installed ffmpeg libraries on ubuntu, following the guide
[21:26] <dott_infernus> almost here, everything is ok. I want to use this library on my own project with Qt Creator..but I didn'y find any wiki to link ffmpeg libraries into qt creator.
[21:27] <dott_infernus> I've tried to include some libraries into project file (.pro) but when I try to compile, the compiler gives me undefined reference..
[21:28] <stqn> I know you can manually edit the .pro file, but theres probably a gui for that&
[21:29] <dott_infernus> let me be more clear, I've created a new project, into to main file I call #include <libavutil/...> and go on...if I don't call any function, it compiles correctly...when I call just one function inside the libraries it gives me undefined reference
[21:30] <dott_infernus> stqn, it is what I've done
[21:30] <stqn> for example you can add : LIBS += -lssl in the .pro to link with libssl
[21:30] <stqn> (at least for the project Im working on&)
[21:31] <dott_infernus> ok...may I paste here some rows about my .pro?
[21:31] <dott_infernus> LIBS += /usr/local/lib/libavcodec.a \  /usr/local/lib/libavdevice.a \  /usr/local/lib/libavfilter.a \
[21:31] <dott_infernus> is that wrong?
[21:33] <stqn> cant say for sure, but seems ok to me
[21:34] <dott_infernus> do I need to add -l when I link libs?
[21:34] <stqn> not when you give the complete path, I think
[21:35] <dott_infernus> ah...
[21:36] <dott_infernus> another question..
[21:38] <dott_infernus> I want to compile the examples given to me after the installation of ffmpeg libraries...the examples inside doc/example...but when I launch gcc from terminal...it gives me the same error (undefined reference) ... someone told me that I've missed some libraries....how can I determine which libraries I have to call during that call? Using the makefile will avoid this problem?
[22:25] <tyebud> Hello all.  Does ffmpeg support qt chapter tracks?
[22:32] <durandal11707> tyebud: you have link/sample/file ?
[22:32] <durandal11707> chpl is supported
[22:33] <tyebud> durandal11707: yeah let me upload my example real quick.
[22:33] <tyebud> durandal11707: Here you go - https://dl.dropbox.com/u/132898/keynote_animation_test.mov
[22:35] <durandal11707> i get error: Referenced QT chapter track not found
[22:35] <tyebud> durandal11707: Yeah, same here.  But, it loads and plays the chapters or whatever they're called fine in quicktime
[22:36] <durandal11707> this is complete file?
[22:36] <tyebud> Yep
[22:37] <durandal11707> than it is bug, open bug report with link to this file
[22:37] <durandal11707> you could also put what qt list for chapters
[22:38] <durandal11707> btw, what created such file?
[22:38] <tyebud> This was an export from keynote
[22:38] <cbsrobot> and there is a sprite track aswell
[22:38] <cbsrobot> what is that for ?
[22:39] <tyebud> sprite track?
[22:39] <tyebud> Perhaps suptitles?
[22:41] <durandal11707> perhaps it is chapter for subtitle stream?
[22:41] <teratorn> are there any well-known video resolutions where the width or height is *not* a multiple of 2?
[22:43] <Mavrik> teratorn, multiple of 2 or divisible by 2?
[22:43] <Mavrik> hm
[22:43] <Mavrik> that's the same thing
[22:43] <teratorn> yeah :)
[22:44] <Mavrik> teratorn, pretty much any that don't use chroma subsampling
[22:44] <Mavrik> so, 4:4:4 formats
[22:44] <Mavrik> can be arbitrary
[22:44] <teratorn> yeah, I was just looking for a well-known resolution to hit my co-workers over the head with
[22:45] <Mavrik> well, since most decoders don't support anything else than 4:2:0
[22:45] <Mavrik> it's gonna be really hard to find :)
[22:45] <JEEB> more like the thing is that most commonly used end-user formats use 4:2:0 :P
[22:45] <teratorn> well, so what if there is chroma subsampling. you still have full luma resolution.
[22:45] <teratorn> it just means that certain pixels have the same color values as certain other pixels
[22:46] <JEEB> you generally can't encode subsampled stuff with a non-mod(subsampling) resolution
[22:46] <teratorn> ok that is fair. the actual complain is about doing picture-in-picture compositing (overlays).
[22:46] <Mavrik> teratorn, yeah, but encoders pretty much consistently demand that your video resolution is divisible by subsampled number
[22:46] <teratorn> they think that it has to be done on 2x2 pixel boundaries
[22:47] <teratorn> i say no
[22:47] <teratorn> for YUV420
[22:47] <Mavrik> no reason for it really
[22:47] <Mavrik> :)
[22:47] <durandal11707> people still use that?
[22:48] <teratorn> durandal11707: what? :)
[23:26] <damaru> hi - I am on debian wheezy and want to revert to ffmpeg and not avcon
[23:27] <damaru> got the .deb from the debian multimedia but then can't dpkg -i
[23:27] <damaru> hum...
[23:38] <damaru> ha ok apt-get remove acvon and the libav then download the ffmpeg deb, get the multimedia apt source, then apt-get install -f
[23:41] <AL13N> i have an odd thing: i use -s 640x480 -r 12 and i convert to mp4/ogg/webm; however, the image preview for the webm is stretched into 640x480, while the others have 640x422, subsequently taking an image with -vf frames=1 also stretches the image
[23:41] <AL13N> why would the image preview of mp4 and ogg not be stretched and webm would be stretched?
[23:42] <AL13N> it would only make sense if the -vf frames=1 loses the aspect ratio and the webm having included preview and mp4/ogg not
[23:44] <llogan> damaru: you got it working?
[23:45] <llogan> alternatively you could compile ffmpeg or use a static build
[23:45] <damaru> yep it finally worked, it was just annoying how ffmpeg was pointing to avconv
[23:45] <llogan> yes, i agree.
[23:46] <damaru> now I am trying to convert a .swf to mov or webm but get a incomplete frame
[23:48] <damaru> http://pastebin.com/pAAgSLRi
[23:49] <damaru> ousp it cuts the end
[23:50] <damaru> ho no - it's all right
[23:50] <damaru> with the error at the end of the pastbin
[23:50] <llogan> does the output look ok?
[23:50] <damaru> the output works for the few first second
[23:50] <llogan> the inpt keeps changing frame size and pixel format
[23:50] <damaru> then blanks up
[23:51] <llogan> with what player?
[23:51] <damaru> the flash video was made by a beginner so their might be error
[23:51] <damaru> with vlc
[23:51] <damaru> can I skip 'incomplete frame' ?
[23:52] <llogan> i'd blame the input, but i don't really know what to suggest
[23:52] <llogan> can vlc play the input swf file?
[23:52] <damaru> yeah I might screen record the video - vlc cannot but gnash was able to play it
[23:53] <damaru> any good recommendation for screen video recording on debian?
[23:56] <damaru> ha good old kdenlive
[23:57] <llogan> ffmpeg -f x11grab -r 30 -s 1024x768 -i :0.0 -vcodec libx264 -crf 18 -preset ultrafast -pix_fmt yuv420p output.mp4
[23:57] <stqn> damaru: the Arch wiki says ffmpeg& https://wiki.archlinux.org/index.php/FFmpeg#Screen_cast_to_.webm
[23:57] <damaru> ha!
[23:57] <damaru> that's sweet
[23:58] <llogan> that wiki page needs a good cleanup
[23:59] <stqn> I thought someone would say that ;)
[23:59] <stqn> Im not an expert myself&
[00:00] --- Wed Jan 16 2013


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