[Ffmpeg-devel-irc] ffmpeg.log.20120603

[burek]

[00:04] <smjms> should sws_flags be set before input file names or after them?
[00:05] <smjms> I get an error, if I set them after the input
[00:05] <smjms> "well maybe you should do it the other way"
[00:05] <smjms> but does it only have effect when set after the input file name?
[00:14] <smjms> does anyone have any questions?
[00:16] <smjms> why are you here?
[00:19] <smjms> ah, no one is here
[02:09] <kn100`> Is it possible to join multiple videos together using ffmpeg
[02:09] <kn100`> as in use these 5 input videos to make 1 long output video in this format
[05:27] <onitaL> Hello, How do I "Fix VBR mp3 header" with  ffmpeg (or lame) http://ennorehling.tumblr.com/post/24142173417/solved-file-marked-as-permanent-failure-on-server
[05:33] <onitaL> " ffmpeg  -i a.mp3  -acodec copy -y b.mp3"
[05:34] <onitaL> seems to have worked
[09:59] <netphreak> Hi all!
[10:01] <netphreak> Anyone know how i can make ffmpeg rescale video proportionally "only" if width or height is larger than a defined size?
[10:04] <burek> and what to do if not
[10:04] <netphreak> just leave it as it is..
[10:05] <burek> so no need for ffmpeg at all in that case?
[10:05] <burek> you can obviously use a shell script for that, first query the video size and if needed, run ffmpeg, if not then quit
[10:05] <netphreak> Only if the source width or height is larger than a certain size..
[10:06] <ubitux> it's possible with eval
[10:06] <ubitux> (the ffmpeg eval builtin)
[10:08] <netphreak> burek: Could be nice to avoid quering ffmpeg too many times..
[10:09] <netphreak> ubitux: Got an example og the eval solution?
[10:09] <ubitux> http://ffmpeg.org/ffmpeg.html#scale
[10:10] <ubitux> http://ffmpeg.org/ffmpeg.html#Expression-Evaluation
[10:11] <netphreak> thanks :)
[10:12] <burek> hm, yes, he could use min(real_x, max_x) to scale one dimension
[10:13] <burek> but in the case that real_x is lower than a defined size, ffmpeg would scale 1:1 right?
[10:14] <burek> i.e. wouldn't just quit, but it would "rescale" to the same size, if I understood correctly?
[10:14] <ubitux> yes, likely
[10:15] <ubitux> actually i don't think the scale filter will do anything but the issue is that it will re-encode anyway
[10:16] <netphreak> That's not a problem, as i need to reencode to a new bitrate anyway..
[10:18] <ubitux> another issue is that it needs a more complicated heuristic to deal with both condition at the same time
[10:19] <ubitux> (you need to check W and H when setting the new W, and W and H when setting the H)
[10:19] <ubitux> (otherwise it might not do what you want)
[10:24] <netphreak> ok..
[10:24] <netphreak> thanks for all your help :)
[11:33] <rainmaker1> Hi, I guess that answer is no but just to confirm, it is not possible to do multi-pass encoding with live stream? Or is there any way we can achive better results with fast moving scenes, we see from time to time a few "cubes" on the screen no matter what profiles we use...
[11:55] <atlithorn> hello, I've been in contact with Nicolas George on the mailing list about my problem, haven't quite been able to crack it yet
[11:56] <atlithorn> ffmpeg -i test1.flv  -i test2.flv -filter_complex '[0]scale=iw/2:ih/2,pad=2*iw:ih[left];[1]scale=iw/2:ih/2[right];[left][right]overlay=main_w/2:0;[0:1][1:1] amerge' out.flv
[11:58] <atlithorn> I get No opaque field provided, an AVABufferSinkParams struct is required
[12:00] <atlithorn> I'm trying to mix 2 videos together via overlay for images and amerge for audio
[23:22] <smjms> you don't find it by searching, and the man page could fill a book
[23:23] <burek> The generic syntax is: ffmpeg [global options] [[infile options][‘-i’ infile]]... {[outfile options] outfile} ...
[23:25] <smjms> so what separates global options and infile options?
[23:27] <smjms> or just, what are global options?
[23:30] <robertzaccour> when trying to record my screen and audio I get runaway video. after recording the video plays much faster than the audio. here's my input ffmpeg -f alsa -ac 2 -i pulse -r 30 -s 1366x768 -f x11grab -i :0.0 -vcodec msmpeg4v2 -qscale 2 screencast.avi any suggestions?
[23:33] <burek> your cpu might be slow
[23:33] <burek> it would be wise to first grab to something lossless and later to encode to what you want
[23:34] <robertzaccour> burek, how do I do that?
[23:34] <CuZnDragon> Hello,  Is there an issue with ffmpeg git repository and opencv 2.4.0
[23:34] <burek> http://ffmpeg.gusari.org/viewtopic.php?f=25&t=594
[23:34] <burek> CuZnDragon, could be :) what issue?
[23:35] <CuZnDragon> I am getting an opencv not found even though it is installed.
[23:36] <burek> is opencv-dev installed?
[23:36] <CuZnDragon> I am on a source distribution and it is all installed.
[23:37] <robertzaccour> burek, those outputs failed
[23:37] <burek> robertzaccour,
[23:37] <burek> can you please use pastebin.com, to show your command line and its output?
[23:37] <burek> CuZnDragon, then check config.log file to see what exact error is and troubleshoot it
[23:38] <CuZnDragon> http://pastebin.com/Q3V7uTRj    that is the opencv error section from config.log
[23:39] <robertzaccour> burek, http://pastebin.com/gP71NDuw
[23:40] <CuZnDragon> a lot of linker warnings ond an error with undefined reference to cvCreateImageHeader
[23:42] <burek> robertzaccour, that may be a bug
[23:42] <burek> can you please use ffmpeg's bug trac to report it?
[23:44] <burek> CuZnDragon, your opencv version does not match
[23:44] <burek> you have it installed but it lacks some functions, expected by ffmpeg
[23:45] <burek> this is most possibly the result of mismatching version of opencv
[23:45] <CuZnDragon> That is what I was asking if there was a problem with 2.4.0 as that is the version of opencv that we have.
[23:46] <robertzaccour> burek, is there a way to uninstall this one and install the proper version?
[23:48] <robertzaccour> burek, not sure how to report the bug. I installed ffmpeg improperly maybe? I can pastebin the way I installed it to begin with
[23:48] <burek> robertzaccour, well, the best would be to compile your ffmpeg, but as I can see you did compile it, so I assume it's a bug
[23:49] <CuZnDragon> libopencv_calib3d.so.2.4.0 is definately installed along with the shorter links.
[23:49] <burek> if you report it there, developers might give you more info on that
[23:49] <burek> CuZnDragon, is that the latest version?
[23:49] <CuZnDragon> Yes released may 7th
[23:50] <robertzaccour> burek, here's the tutorial I used http://pastebin.com/ADSqwmXV
[23:50] <burek> you could ask in opencv support channel maybe to see if the error message is about mismatching versions or something else..
[23:50] <burek> but I guess they'll bounce you back here
[23:51] <burek> robertzaccour, that's ok
[23:51] <robertzaccour> I don't know much about ffmpeg. I got that tutorial from I forgot where and someone helped me figure out an input command that finally worked. The ins and outs I don't know much of
[23:52] <burek> let me ask other people about that, just a sec robertzaccour
[23:53] <robertzaccour> ok thanks
[23:53] <burek> btw, maybe you are running it as root and your DISPLAY (desktop) is not assigned to root as it is to the regular user
[23:54] <robertzaccour> burek, I'm not sure what the difference would be. Could that affect the performance?
[23:56] <burek> well, for example, on my machine (debian), when I reboot the machine, I log in as a regular user and use my desktop and stuff, but if I open the termina and login as root (using su) then I can't access my desktop
[00:00] --- Mon Jun  4 2012