[Ffmpeg-devel-irc] ffmpeg.log.20130723

burek burek021 at gmail.com
Wed Jul 24 02:05:01 CEST 2013


[00:00] <brontosaurusrex> -crf = 0 = lossless, -crf = 23 = lossy
[00:00] <Aprel> k, brb
[00:00] <brontosaurusrex> basically -crf 23 will make smaller and uglier files
[00:12] <w1jp> Is there an updated 'how-to' on building the ffmpeg-all on Mac OS X? For example, I understand that yasm isn't required anymore.
[00:13] <w1jp> I also am noting that ffplay doesn't build and I didn't see any errors to that effect.
[00:14] <brontosaurusrex> w1jp, what guide are you following?
[00:14] <Aprel> K, I'm back. Still seeing desync very visible 3 mins into video from screen capture. 10min capture = 1GB file with -crf 23.
[00:15] <w1jp> The one on the wiki (trac.ffmpeg.org)
[00:15] <brontosaurusrex> Aprel, and the player that you are using is?
[00:15] <w1jp> Want to build ffplay
[00:15] <w1jp> I imagine sdl
[00:16] <brontosaurusrex> yeah, i remember that ffplay (was never able to build it)
[00:16] <Aprel> brontosaurusrex: totem. Also see the exact same desync in editing software pitivi and kdenlive, so it's not the paler
[00:16] <brontosaurusrex> Aprel, how do you measure desync?
[00:17] <Aprel> brontosaurusrex: I'm watching a video w people talking and I notice the lips don't match the words. Those framerates I gave earlier I got examine a video in editing software.
[00:18] <Aprel> So I play a video, record the screen capture, and watch the screen capture (for this debugging)
[00:18] <brontosaurusrex> Aprel, what would happen if you convert the clip with ffmpeg to something I-frameish? like prores maybe or that avid thingy
[00:19] <Aprel> brontosaurusrex: ffmpeg command?
[00:19] <brontosaurusrex> Aprel, also, what happens with mplayer ?
[00:19] <brontosaurusrex> Aprel, hold on ...
[00:21] <brontosaurusrex> Aprel, ffmpeg -i in.file -vcodec dnxhd -acodec pcm_s16le -b:v 120M -f mov out.mov
[00:22] <brontosaurusrex> i'am pretty sure kdenlive should have some good support for dnxhd (from memory)
[00:22] <Aprel> k, I will try that.
[00:22] <brontosaurusrex> no promisses, i'am guessing
[00:24] <Aprel> All right. It's encoding.
[00:29] <Aprel> It's gonna take a little bit. I need to do like 10 mins of this video I have handy to really know if it's resyncing.
[00:30] <brontosaurusrex> Aprel, another guess would be something to do with variable-frame-rate and mkv container, try mp4
[00:30] <brontosaurusrex> Aprel, or try to capture to say dnxhd
[00:31] <Aprel> Also had another video up in a player just like 300x300 and screencapture that player with -crf 23. Very bad, quality, obviously. I can't really see people's mouths to judge the desync, but it doesn't seem to desync as much if at all with only 300x300 of the screen.
[00:31] <brontosaurusrex> (But do some reading, i think dnxhd is resolution dependant, or it used to be)
[00:31] <Aprel> Also I used to capture in the mp4 container before I knew what mkv was, and I got the same problem.
[00:34] <Aprel> Just finished the encoding. -vcodec dnxhd didn't make a difference.
[00:35] <brontosaurusrex> Aprel, try to capture to dnxhd directly
[00:35] <brontosaurusrex> but i think you must use standard hd - 1920x1080 (not 1920x1200)
[00:36] <Aprel> brontosaurusrex: like this?:  ffmpeg -f x11grab -r 25 -s 1920x1080 -i :0.0 -f alsa -ac 2 -i pulse -vcodec dnxhd -crf 23 -preset ultrafast -acodec pcm_s16le output.mov
[00:37] <brontosaurusrex> yeah
[00:37] <brontosaurusrex> no
[00:38] <brontosaurusrex> skip "-crf 23 -preset ultrafast -acodec pcm_s16le"
[00:38] <Aprel> k.
[00:39] <Aprel> brontosaurusrex: video parameters incompatible with DNxHD.
[00:40] <Aprel> I think I need to set a bitrate... so add -b 175M?
[00:40] <Aprel> i ffmpeg outputs Frame size: 1920x1080p; bitrate: 175Mbps; pixel format: yuv422p10; framerate: 24000/1001 as one of the valid profiles, but I don't know how to set that in the command line
[00:41] <Aprel> nvm, just got it.
[00:42] <brontosaurusrex> what command did you use?
[00:43] <Aprel> just added -b 175M to the command line and it started without errors.
[00:43] <brontosaurusrex> ok
[00:45] <Aprel> btw, later I'll try capturing a long vdieo at just like 300x300 and see if the audio still is in sync at like 20 mins in. If it's fine at a small screen size, what could be the cause of the problem with only big sizes like 1920x1080?
[00:46] <brontosaurusrex> Aprel, could be a lot of things, including drivers and whatnot
[00:47] <Aprel> ugh, already had enough "fun" trying to fix a video tearing issue in ubuntu. :/
[00:47] <brontosaurusrex> also the problem is that kdenlive is something thats hard to trust
[00:48] <brontosaurusrex> so the decoder side can be problematic somehow
[00:48] <brontosaurusrex> what OS are you running? ubuntu?
[00:48] <Aprel> haha, I'm just lucky if I can get kdenlive to not crash
[00:48] <Aprel> yeah ubuntu 13.04
[00:49] <brontosaurusrex> Aprel, did you test lightworks beta?
[00:50] <Aprel> brontosaurusrex, yeah, but it's a little above my learning curve. Plus I had some codec issue (what I encoded in ffmpeg didn't play right in lightworks), but I tried the beta like several months ago so could be better
[00:51] <brontosaurusrex> yeah :|
[00:51] <brontosaurusrex> video editing in nix is just sad
[00:52] <Aprel> btw, doing it with dnxhd not only cause desyncing, but audio dropping (like people talking and their word drops as they say it).
[00:52] <brontosaurusrex> I did some editing with lightwork like 10 years ago (they were using dos then)
[00:52] <brontosaurusrex> so i had high hopes for a linux version
[00:52] <brontosaurusrex> lightworks*
[00:52] <Aprel> yeah, I want to use unix so bad to edit video, so many promising programs...so many problems with them.
[00:53] <Aprel> damn, I have to run, but I'll be back in 30 mins, if you happen to be on.
[00:53] <brontosaurusrex> have fun
[00:54] <eggyknap> Can someone explain this "No channel layout" error for me? http://pastie.org/8165503
[00:55] <eggyknap> I originally figured it meant I needed -ac, to see that what ffmpeg thought were stereo inputs were really mono... but I added that, and it correctly sees they're mono, and it still complains
[00:57] <eggyknap> The anull filters are just to allow me to refer to streams by nice names rather than [0:0], etc., which is helpful for the more general development I'm doing.
[00:58] <eggyknap> ...but perhaps they're not working as I'd like, and I just don't know it.
[01:34] <Aprel> Back. If there's a possibility that it's a driver issue causing the desync, it probably is, because I've got an nVidia GTX 550 Ti and as nice as the card is, it likes to cause a lot of problems.
[01:37] <eggyknap> Is there any reason to believe multiple ffmpeg processes would perform better than one ffmpeg process with an intelligent -threads setting?
[01:39] <Zerxer> I'm trying to use ffmpeg to record a dshow input but right now I'm having trouble with the audio. here's the command I'm using: ffmpeg -f dshow -s 1280x720 -r 59.94 -pix_fmt uyvy422 -i video="Blackmagic WDM Capture" -r 29.97 -pix_fmt yuv420p -t 15 out.mp4
[01:39] <Zerxer> that Blackmagic WDM Capture should include its own audio stream but that command itself makes my video not have any audio, is there something else I have to attach to the command?
[01:39] <Aprel> Zerxer: does this help?: http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20grab%20the%20desktop%20%28screen%29%20with%20FFmpeg
[01:41] <Zerxer> Aprel: I'm capturing from an external device but I did try looking into using :audio="" but there's no specific audio stream listed when I list devices. I tried using Blackmagic WDM Capture as both the video and audio settings but it threw an error that the audio stream wasn't found
[01:45] <jankowiak> how can I check how long an encode lasted?
[01:45] <Zerxer> I may have figured it out
[01:46] <jankowiak> I'm looking at the out put but I don't see any time output
[01:47] <Zerxer> my last question is this: if I'm capturing & encoding with a command like that, how do I safely tell it to stop capturing/outputting? do I simply close the command prompt, or will that cause it to be unclosed and corrupted in some way?
[01:51] <Aprel> Zerxer, when I do screen capture, I use Ctrl-C to stop. If you press it only once, it tells ffmpeg to stop and clean up. 2+ times means abort.
[01:52] <Aprel> Hardclosing the command prompt might corrupt the file. It will depend on the container.
[01:52] <Zerxer> Aprel: awesome, thanks, Ctrl-C is what I wanted :) can't wait to give this all a spin and see how it does
[01:53] <posciak> hi, I wanted to encode a stream that would have SEI recover points instead of IDRs when possible, I thought open_gop to x264 would be the option I need. I tried: ffmpeg -i in.mp4 -c:v libx264  -x264opts open_gop=1 -c:a copy out.mp4 and some variations of open_gop argument, but x264 keeps reporting "open_gop=0"... what am I doing wrong?
[01:53] <Aprel> Zerxer, good luck :)
[01:53] <Zerxer> the device I'm using outputs at 60fps so every other capture software I've used has wanted to write 60fps to disc and my hard drive is just not fast enough to do that, so I'm very excited that I discovered how to use ffmpeg to both capture it and write it to disc as 30fps
[01:53] <Zerxer> hoping to finally be done with out of sync issues
[01:55] <Aprel> Zerxer, well I hope it works out for you. I came here trying to work out out-of-sync issue captures myself :/ But I've got a graphics card, so I think that's overcomplicating things.
[02:17] <Zerxer> hm still out of sync for me too& maybe I shouldn't try changing the pixel format while capturing? the cmd log did have a lot of dropped frames
[02:19] <Zerxer> or if I can increase the buffer, says it hit 121%
[02:23] <Zerxer> what's the best way to have it capture the raw/uncompressed video but still have it cut the framerate in half before outputting to a file?
[02:28] <Aprel> Zerxer: check your CPU during the capture and see if it's close to 100%.
[02:29] <Zerxer> good idea
[02:30] <Aprel> Also feel free to report back with any progress you make. I'm having a similar issue with out-of-sync. Could be the ffmpeg code itself?
[02:31] <Zerxer> I've been having nothing but out of sync problems with my Blackmagic Intensity Shuttle itself so I'm not sure I'd jump on ffmpeg being the cause for my issue :(
[02:31] <Zerxer> the conclusion I came to is my hard drive is definitely not fast enough to handle writing 720p at 60fps
[02:31] <Zerxer> which is why I'm resorting to ffmpeg now to cut the frames in half. my last option that I'm avoiding is to use motion jpeg
[03:44] <Zerxer> I checked my CPU usage while recording and it stayed around 60%
[03:44] <Zerxer> but the cmd log, frequently, would say in red text "real-time buffer 121% full! frame dropped"
[03:49] <Aprel> hm, then you could be right about the hard drive being the bottleneck. btw, the blackmagick device, is that over usb (sorry I have no idea what that is)
[03:49] <Zerxer> yup, usb 3.0
[03:50] <Zerxer> I know absolutely nothing about video-related items, completely new in this area, but should I also be capping the bitrate of the output file?
[03:51] <Zerxer> I might as well try and not change the pixel format of it, see if that helps anything
[03:55] <uersbob> hi, im writing a c# screen recording app, and i am using the following line to feed images taken to ffmpeg using image2pipe.  It works, but the timestamps of the frames seem to be off, since when i sync it with audio, the frames are a bit to fast near the start, then slowly balance out near the end
[03:55] <uersbob> here is the line i am using.  -f image2pipe  -i pipe:.bmp  -c:v libx264  -an -y  "video.mp4"
[03:55] <Aprel> Yeah, I was thinking maybe the buffer overfill was on the usb side, but shouldn't be a problem with usb 3.0. Could be hard drive, could be ffmpeg...it's a frustrating issue, I know. You could try less bitrate=smaller file=less hd use and see if that helps. btw, what command line command are you using for the capture?
[03:56] <Aprel> uersbob: funny you should ask. We have been having out-of-sync capture problems ourselves....
[03:57] <uersbob> this is after i run another ffmpeg command using PTS to make the framerate correct, as a new video file, since it plays to fast normally
[03:59] <uersbob> i guess i am asking, how can i output the frames with the correct timestamps, when the recording is taking place
[04:10] <Zerxer> I tried making the filename .avi since that's what my other capture programs made, for a raw/uncompressed file, and then I played 10 mins and monitored the output/cpu usage as I did. I was very impressed, no dropped frames, cpu below 15%, thought I figured it out
[04:10] <Zerxer> then I went to play back the .avi file and it was very low quality, lol. but doing .mp4 causes 60% and dropped frames :(
[04:13] <Aprel> Zerxer: what's your ffmpeg command line to creat teh avi file?
[04:14] <Zerxer> ffmpeg -f dshow -s 1280x720 -r 59.94 -pix_fmt uyvy422 -i video="Decklink Video Capture":audio="Decklink Audio Capture" -r 29.97 out.avi
[04:14] <Zerxer> (or out.mp4, which makes higher quality video, but dropped frames)
[04:15] <relaxed> It drops frame to achieve 30pfs.
[04:15] <relaxed> er, 30fps
[04:15] <relaxed> Is the input interlaced?
[04:16] <Zerxer> I mean it says the buffer is 121% full, frame dropped
[04:16] <Zerxer> not that it's dropping frames to achieve the 30fps
[04:16] <Zerxer> the input is 720p60
[04:17] <Zerxer> or well 720p59.94 to be completely true
[04:17] <relaxed> 59.94 does not imply progressive content.
[04:19] <Zerxer> oh, I thought the "p" did though. it's progressive
[04:21] <relaxed> I thought fractional frame rates meant the content was interlaced
[04:21] <relaxed> the correct way to specify the input frame rate is -r 60000/1001
[04:22] <Zerxer> hm do you think that's contributing to my issue then?
[04:22] <relaxed> and the output should be -r 30000/1001
[04:23] <relaxed> You need to watch the source frame by frame and make sure it's not interlaced.
[04:24] <Zerxer> I know it's not interlaced at all. it's coming out of an xbox 360 that's outputting at 720p and the blackmagic is set to progressive input as well
[04:25] <Aprel> what if you tried -vcodec libx264 -crf 0 -preset ultrafast -acodec pcm_s16le ? This will use hardly any cpu and you can see if the difference is that 15%-60% cpu increase that's causing frame drop (i.e. overfilling the buffer into cpu processing). Maybe the codec can only use 2 cores so it's pushing them all the way and 65% is on a quad core cpu?
[04:27] <Zerxer> that's possible. it is indeed a quad core
[04:28] <Zerxer> would I put that before or after the -i input? does it apply to the input or the output?
[04:29] <Aprel> After -i input. It just means don't do any on-the-fly cpu processing during capture.
[04:30] <Aprel> So if the desync looks even worse with that command, it probably means a hdd bottleneck (because it write raw video and uses a lot of hdd space). If the desync goes away, then the cpu isn't keeping up with the encoding and you can capture in raw and encode after you're done capturing.
[04:32] <Zerxer> since it's writing raw video, will I still be able to force the output to 30fps? cause I know my hdd is going to bottleneck on the raw 60fps
[04:32] <Zerxer> and that'll ruin the test
[04:32] <Zerxer> going to run it now
[04:32] <Aprel> I think so.
[04:33] <Zerxer> got some errors right away with that: track 1: could not find tag, codec not currently supported in container. and Could not write header for output file #0 (incorrect coedc parameters ?): Error number -1 occured
[04:34] <Aprel> sorry, you need to use the .mkv container
[04:34] <Zerxer> gotcha
[04:34] <Aprel> can you play that? Otherwise, it might be compatible with other containers, just not sure which.
[04:35] <Zerxer> got the buffer error right as it started, after I hit enter on the command, but it's going through now and cpu usage is below 20%. going to try actually doing things in the game now
[04:35] <Zerxer> yeah I can
[04:35] <Aprel> k, best of luck
[04:42] <Zerxer> no issues at all while recording& 15% cpu, no dropped frames (except it giving the buffer error right when it started and right when it ended). playing back the MKV file now
[04:45] <Zerxer> 6 minutes into the video and there's no sync issues! a great sign. you said that this should do no processing though, right? just a raw dump of quality? the quality just seems slightly less than what it was as the mp4 without those settings, but I could just be looking at it too much
[04:48] <Aprel> Zerxer: I was under the impression it's raw. Got that command from http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20grab%20the%20desktop%20%28screen%29%20with%20FFmpeg.
[04:49] <Aprel> It might do a very minimal processing.
[04:50] <Zerxer> I think it's fine, I have my girlfriend watching the video now and she said the quality is good. I've just been staring at all this for too long and just got done playing it directly off the xbox
[04:50] <Aprel> But it says this is the command to use for "uncompressed video/audio" which I read as raw.
[04:50] <salamanderrake> hello having issues streaming to twitch.tv http://pastebin.com/SL8Df3jA
[04:51] <salamanderrake> I used the command from here http://trac.ffmpeg.org/wiki/StreamingGuide
[04:51] <Zerxer> and thanks, you've been extremely helpful :) I hope you're able to resolve the issue you're having
[04:52] <salamanderrake> ffmpeg -f x11grab -s 1920x1200 -r 15 -i :0.0 -c:v libx264 -preset fast -pix_fmt yuv420p -s 1280x800 -threads 0 -f flv "rtmp://live.twitch.tv/app/live_********_******************************"
[04:53] <Aprel> Zerxer, thanks, glad to help. You can continue to play around with it. Seems like your problem was a combo of hdd write speed and cpu limits.
[04:53] <salamanderrake> oops thought you was talking to me Zerxer
[05:01] <salamanderrake> shoud -pix_fmt yuv420p be for 16:10 resolution recording?
[05:05] <relaxed> salamanderrake: yes, and it's the color format best supported for streaming.
[05:05] <salamanderrake> ok
[05:11] <salamanderrake> do I have to use libx264 for the video?
[05:13] <relaxed> I guess you don't have to but it's a good codec and is well supported.
[05:14] <salamanderrake> well for me its borked
[05:20] <Zerxer> Aprel: just saw in the cmd output that it actually says to hit q to stop, so there's another way to do it
[05:21] <Zerxer> then again, you do screen capture, so cmd may not be in focus for you (just caught myself there)
[05:23] <Aprel> Zerxer: you're right. And I've seen that line every time I've used ffmpeg, lol. As soon as I read that, I remembered in my head the '[q]' in the output. Never actually read that whole output line, lol. Thanks for the tip :)
[05:24] <Aprel> Zerxer: That might read sarcastic, but seriously, I never internalized the [q] shortcut despite seeing that output line all the time, lol :)
[05:24] <Zerxer> I only caught a quick glance of it and was like "wait what was that"
[05:25] <salamanderrake> here is the output from my terminal http://pastebin.com/mjGJvDeV
[05:25] <relaxed> Zerxer: -t $time
[05:26] <Aprel> Zerxer:Ha, yeah, ffmpeg output goes fast. Hope that capture command continues to work well for you.
[05:26] <Zerxer> relaxed: ? I was using that flag earlier today but I wouldn't use it for actual capture runs since I don't know how long we'd be playing the game :)
[05:27] <Zerxer> if you mean to see the output better, can at least scroll back up through it all once you end the capture
[05:28] <Aprel> Zerxer: true. I should pipe it to file more often because it floods my terminal.
[05:38] <eggyknap> Can someone explain this "No channel layout" error for me? http://pastie.org/8165503
[05:39] <eggyknap> I originally figured it meant I needed -ac, to see that what ffmpeg thought were stereo inputs were really mono... but I added that, and it correctly sees they're mono, and it still complains
[05:39] <eggyknap> The anull filters are just to allow me to refer to streams by nice names rather than [0:0], etc., which is helpful for the more general development I'm doing.
[06:23] <salamanderrake> is there a quick way to see if its libx264 thats causing my segmentation fault?
[06:34] <Mr_Ewscoba> salamanderrake yes try mpeg2video as vcodec ?
[06:49] <salamanderrake> how do I do that?
[06:50] <salamanderrake> ffmpeg -f x11grab -s 1920x1200 -r 15 -i :0.0 -c:v libmpeg2video -preset fast -pix_fmt yuv420p -s 1280x800 -threads 0 -f flv rtmp://live.twitch.tv/app/`cat ~/.twitch_key` does not work
[06:55] <salamanderrake> ok got the same error
[07:10] <Mr_Ewscoba> salamanderrake no
[07:10] <Mr_Ewscoba> -c:v mpeg2video
[07:11] <Mr_Ewscoba> and preset wont work for mpeg2video
[07:11] <salamanderrake> ahh not compatible with flv
[07:12] <Mr_Ewscoba> try the mpeg4 codec then not libx264, it should be flv compatible :)
[07:13] <salamanderrake> ok mpeg4 works
[07:13] <salamanderrake> mpeg4 @ 0x7f0f45c66780] header damaged
[07:13] <salamanderrake> saved it to mpg
[07:13] <salamanderrake> thats what I got
[07:15] <Mr_Ewscoba> try -vcodec msmpeg4
[07:16] <salamanderrake> instead of -c:v ?
[07:16] <Mr_Ewscoba> Im not sure, but flv and x264 might not be a good mix, something tell me that you can only use mpeg4 for flv
[07:16] <Mr_Ewscoba> yeah or just -c:v msmpeg4
[07:17] <salamanderrake> unknow format
[07:17] <salamanderrake> missing an m
[07:17] <salamanderrake> and no it did not work
[07:18] <salamanderrake> [flv @ 0x6c54c0] Video codec 'msmpeg4v3' for stream 0 is not compatible with FLV
[07:18] <salamanderrake> Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
[07:21] <Mr_Ewscoba> What happends if you remove the -c:v blah completely from the line
[07:21] <Mr_Ewscoba> ?
[07:21] <Mr_Ewscoba> ffmpeg -f x11grab -s 1920x1200 -r 15 -i :0.0 -pix_fmt yuv420p -s 1280x800 -threads 0 -f flv
[07:22] <salamanderrake> lol it works
[07:22] <Mr_Ewscoba> It should choose the encoder best suited itself then :)
[07:22] <Mr_Ewscoba> What encoder did it use then ? :)
[07:22] <salamanderrake> looks like dirt
[07:22] <salamanderrake> and libx264 worked before
[07:22] <relaxed> probably flv as the codec
[07:23] <salamanderrake> this script sorta worked I think before
[07:24] <salamanderrake> http://pastebin.com/mmavyTQn
[07:24] <salamanderrake> sorry
[07:24] <salamanderrake> wrong one
[07:24] <salamanderrake> thats to save to disk
[07:25] <salamanderrake> why doesn't this one work from here for twitch.tv http://trac.ffmpeg.org/wiki/StreamingGuide
[07:25] <salamanderrake> ahh its old
[07:25] <salamanderrake> thats for 1.0 I have 1.2.1
[07:27] <Mr_Ewscoba> Yup its some old shit, and rtmp and flv is some quite nasty formats with ugly limits, they will always be bugged at best in ffmpeg :)
[07:31] <Mr_Ewscoba> If you just want to stream to some vlc clients for example, you'd be better of using the apple segmenter and http.
[07:34] <salamanderrake> apple? I am on linux
[07:35] <Mr_Ewscoba> -f segment -segment_format mpegts -segment_list_type m3u8 -segment_list /var/www/live/mystream.m3u8 -segment_list_flags +live -segment_wrap 6 -segment_time 10 /var/www/live/mystream-%08d.ts
[07:35] <salamanderrake> o ok
[07:36] <salamanderrake> was trying to do this for a live session on twitch.tv
[07:39] <salamanderrake> I think something is broke on my system
[07:39] <salamanderrake> well I am off to bed
[09:19] <pinPoint> hello
[09:25] <pinPoint> I have question, can ffmpeg be used to address issues with videos?
[09:25] <pinPoint> corruption from let's say drive collapsing, etc?
[09:27] <pinPoint> I have the file but it is a R3D file... :/
[15:32] <mcr_> Hi, I have a problem. I'm using -t option to trim content. Here is full command I use: ffmpeg -ss 00:00:00 -t 00:10:10 -i big_buck_bunny_1080p_h264.mov -codec copy big_buck_bunny_1080p_h264_short.mov
[15:32] <mcr_> I'm getting error: -t is not an input option
[15:33] <mcr_> and my file isn't trimmed at all
[15:33] <mcr_> when I do -t 00:00:30, ffmpeg trims file to 30 seconds, as expected
[15:34] <mcr_> what am I doing wrong?
[15:36] <relaxed> mcr_: -t goes after the input
[15:39] <mcr_> ok, I have no error when i put -t after input, but output file size stays the same, same as reported length in VLC.
[15:41] <mcr_> I'm sorry, everything's ok now :)
[15:41] <mcr_> thanks
[16:25] <Fjorgynn> :D
[16:33] <salamanderrake> >D
[16:53] <eggyknap> Can someone explain this "No channel layout" error for me? http://pastie.org/8165503
[16:53] <eggyknap> I originally figured it meant I needed -ac, to see that what ffmpeg thought were stereo inputs were really mono... but I added that, and it correctly sees they're mono, and it still complains
[16:53] <eggyknap> The anull filters are just to allow me to refer to streams by nice names rather than [0:0], etc., which is helpful for the more general development I'm doing.
[16:53] <eggyknap> (perhaps there's a better way to assign those names... that's the first way I came up with)
[18:00] <bAndie9100> hi all
[18:03] <bAndie9100> http://pastebin.com/QDpDt4vb
[18:03] <bAndie9100> there is my question
[18:03] <bAndie9100> i have raw video on stdin and audio on microphone. how to grab them togather?
[18:56] <Bourbon> is it possible to do mp4-container output with ffmpeg?
[18:56] <Bourbon> I mean, through pipes
[19:10] <mkrufky> is there a guide anywhere for porting applications that depend on ffmpeg 1.x to ffmpeg 2.0 ??    i notice that some av_buffersink_foo & avfilter_foo functions have been deprecated
[19:11] <Bourbon> there's 2.0?
[19:14] <JEEBsv> yes, the current release is 2.0
[19:14] <mkrufky> heh
[19:15] <mkrufky> ...then im guessin that you guys dont know of any porting guide or some kind of reference of which functions to use instead of the deprecated ones
[19:15] <JEEBsv> the changelog should note some of the stuff
[19:15] <JEEBsv> changes.txt or something
[19:15] <JEEBsv> also going through the doxygen is useful as well
[19:16] <mkrufky> Changelog just lists the new features
[19:17] <mkrufky> i was hoping to port my code to use 2.0, in hopes that maybe the 2pass encoding might be better in 2.0 (even tho Changelog makes no mention of improvements to 2pass encoding, i still think its worth a try)
[19:18] <mkrufky> ...also i stand to benefit from the 10% efficiency increase in aac
[19:18] <JEEBsv> there was some API changes log as well, you should also try reading through the avfilter doxygen if you were using libavfilter before
[19:18] <mkrufky> ah, perfect, that should help -- thanks
[19:18] <mkrufky> awesome
[19:18] <mkrufky> doc/APIchanges
[19:18] <mkrufky> thanks :-)
[19:23] <axorb> hey guys, is it safe to say that -ss x before -i will seek to the first keyframe after time x?
[19:23] <axorb> will always*
[19:33] <axorb> I know it will always seek to a keyframe, but is that keyframe always after the given time or the nearest match?
[19:36] <xlinkz0> axorb: no
[19:36] <xlinkz0> or actually nvm me
[19:40] <axorb> the seeking guide example shows the fast seek picking the keyframe before the time, so I guess not
[19:41] <axorb> makes sense anyway because you'd rather not seek backwards after going too far
[21:04] <mkrufky> ok, so the doc/APIchanges file made the avfilter_graph_parse_ptr() port an easy one :-P
[21:04] <mkrufky> but im still hunting for av_buffersink_get_buffer_ref(), av_buffersink_poll_frame(), avfilter_copy_buf_props(), avfilter_unref_bufferp() & avfilter_uninit()
[21:04] <JEEBsv> p1
[21:05] <JEEBsv> ugh, damn small laptop keyboard
[21:14] <matttt> Hi there I'm trying to take frames from an mts file. What I'm noticing are lines in certain parts of my images however when viewing the video in media player classic these lines are not there even when viewing frame by frame. I'm using the command:  .\bin\ffmpeg.exe -i .\00001.MTS -dframes 100 -ss 00:00:00  image-%d.jpeg Any thoughts?
[21:24] <wawrek> hello
[21:24] <wawrek>  
[21:25] <wawrek> I have problem trying to run ffmpeg filtering examples
[21:25] <wawrek> i get this error: Unknown input format: lavfi
[21:44] <llogan> matttt: can you provide a link to one of the images that shows the lines?
[21:46] <matttt> llogan: actually if it makes any sense to you I've narrowed it down to ffmpeg and all other programs seem to open my mts file as 1440x1080. Media player classic opens it at 1920x1080. It seems the scaling is what is causing the lines. I'll try get a link to you once I can!
[21:54] <wawrek> fflogger: I will do that, i understand
[21:56] <matttt> fflogger: will do
[21:57] <llogan> fflogger is the channel bot
[21:57] <matttt> thanks. always good to know hehe ;)
[22:28] <johnsmith> Hi all, has anyone worked with the libav's before? I am just curious on what the "graph" is in the libavfilters, thanks
[23:19] <Joske> Hello.  av_find_input_format("video4linux2") returns NULL, does this mean FFMPEG no longer supports v4l2?
[23:29] <llogan> Joske: ffmpeg still supports it.
[23:31] <Joske> llogan: is it normal for it to return NULL?
[23:32] <llogan> i'm not sure. i don't use this stuff programtically.
[23:52] <Joske> llogan: oh, it's fixed now. i forgot to do  avdevice_register_all();
[00:00] --- Wed Jul 24 2013


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