[Ffmpeg-devel-irc] ffmpeg.log.20120721

[burek]

[00:37] <Digit> Unrecognized option 'codec'
[00:37] <Digit> Failed to set value 'copy' for option 'codec'
[00:39] <Digit> ah.   -vcodec and -acodec
[00:42] <Mavrik> you ffmpeg is old ;)
[00:42] <Mavrik> *your
[00:42] <Digit> yeah, it did spout a load of this shiz is depreciated at me.  i thought that was just debian's futzing.
[00:47] <Mavrik> last time I checked debian wasn't even packaging ffmpeg in the ffmpeg package :P
[02:16] <Xoron> hello all
[02:16] <Xoron> i've been working on some video and i have a bit of a problem
[02:17] <Xoron> and i can't seem to find any functionality within ffmpeg to deal with it
[02:17] <Xoron> basically, i have a video where it has been interlaced with the fields swapped
[02:18] <Xoron> so the bottom field is positioned above the top field
[02:19] <Xoron> is there any special workarounds or flags i should know about so i can swap the fields and de-interlace this particular video properly?
[02:25] <Xoron> ahh, i've managed to find that mencoder has an interleave filter which can swap the fields
[02:25] <Xoron> however, it doesn't seem to have been ported over to ffmpeg
[02:27] <Xoron> no it hasn't, this particular filter is the 'il' filter
[02:28] <Xoron> however, currently, it seems to work through the mencoder wrapper
[02:28] <Xoron> -vf mp=il=s
[02:47] <Xoron> yes, it seems to work ok
[02:47] <Xoron> i just did a full encode
[02:47] <Xoron> and now i have no swapped fields
[02:53] <iive> Xoron: if your image is yuv then you should be using il=s:s to swap the chroma channel too, or the colors would bleed... or be entirely wrong.
[02:53] <iive> rgb should be fine with the above.
[02:55] <Xoron> ahh, makes sense
[02:55] <Xoron> though i don't seem to have had an issue with it
[02:55] <Xoron> the colours look fine
[02:55] <Xoron> i will make a closer check to make sure though
[03:00] <Xoron> hmm, i don't see any colour distortion, i will do another encode and compare
[04:30] <Xoron> hmm, seems my original encode
[04:30] <Xoron> the one i made before i knew about the chroma swapping
[04:30] <Xoron> seems to have less colour distortion than anything else i've encoded
[04:30] <Xoron> this is a tad strange
[04:31] <Xoron> i'm definitely not encoding RGB
[04:41] <Xoron> hmm, i'll have a look at this in more detail tomorrow
[04:42] <Xoron> see what seems to be causing me to get this weirdness
[04:42] <Xoron> anyway, thanks for now
[04:44] <_Nike_> Hi! With RTSP connection what function or var can I detect the codec? I told if the stream is H264, MPEG4, JPG...
[07:27] <trysten> hi guys, how do i discard a video stream?
[07:27] <trysten> ffmpeg is saying "Encoder (codec none) not found for output steam #0:0
[07:27] <trysten> but that is the video, and i don't want that at all!
[07:34] <trysten> how do i discard the video?
[07:48] <trysten> :(
[07:48] <trysten> i know it's a stupid question...
[08:05] <trysten> BUT COME ON
[08:05] <trysten> i'd like to now
[08:05] <trysten> know*
[10:31] <swick> I get an segfault when writing the header for yuv4mpeg http://pastebin.com/gxYMNbH6
[14:17] <arpu> hello
[14:17] <arpu> i encode a live stream for flash player what aac sould i use libfaac vs aac vs libvo-aacenc?
[14:24] <JEEB> fdk-aac
[14:24] <JEEB> fraunhofer's open sourced aac encoder
[14:24] <JEEB> until the license has been checked with several places it'll be nonfree like libfaac, but it's right now the best aac encoder you can get open source
[14:25] <JEEB> it can handle both LC-AAC for higher bitrate use cases, as well as HE-AAC(v2) for low bitrate use cases
[15:07] <Mavrik> JEEB, oh awesome, when did they release it?
[15:08] <JEEB> some time ago, via google's new android version
[15:08] <JEEB> https://github.com/mstorsjo/fdk-aac the repo for it
[15:10] <Mavrik> ah nice, I managed to miss it
[15:10] <Mavrik> thanks for that :)
[15:11] <JEEB> also a random audiofag tested it some time ago (completely non-scientific naturally) http://pastebin.com/ncNFMSJa
[15:15] <Mavrik> hmm, will have to test it, I'm itching to get rid of libaacplus for low-bitrate encodes
[15:15] <Mavrik> if it can do high quality high-bitrate encodes even better
[16:52] <gayboy> there seems to be an error on one of my music cds
[16:52] <gayboy> in a particular time
[16:52] <gayboy> and both mplayer, ffmpeg, ffplay, cdparanoia do not go past that point
[16:52] <gayboy> they just stop
[16:52] <gayboy> but alsaplayer goes through it
[16:52] <gayboy> you only hear a slight click
[16:53] <gayboy> but i need to put the output of alsaplayer to a wav file
[16:55] <gayboy> i believe 'arecord' is what I'm looking for
[18:45] <CoJaBo> I need to convert a video to a series of frames (png/jpeg), possibly decimating the framerate in the process. I could swear I've seen this done before, but I cannot figure out what I need to do to make it work. Ideas?
[18:53] <cbreak> mencoder can do it with mf://, and I bet ffmpeg has something similar
[19:00] <Mavrik> Coderjoe, it's in the FAQ :)
[19:00] <Mavrik> Coderjoe, http://ffmpeg.org/faq.html#How-do-I-encode-movie-to-single-pictures_003f :)
[19:04] <Coderjoe> CoJaBo: ^^^
[19:05] <CoJaBo> Mavrik: Hm, dunno how I missed that; I found the entry for going the opposite way instead..
[19:07] <CoJaBo> Mavrik: Thanks
[19:07] <Mavrik> oh
[19:07] <Mavrik> Coderjoe, sorry *blush*
[19:07] <CoJaBo> Yeh, that happens all the time; usually I'm the one getting pinged tho xD
[19:11] <CoJaBo> man ffmpeg
[19:11] <CoJaBo> ...how did i manage that -_-'
[19:20] <sponsx> Hi, getting an error height not divisible by 2 trying to transcode a video http://pastie.org/4296100
[19:22] <sponsx> Does anyone know how to resolve this?
[19:23] <CoJaBo> Maybe try scaling to a different resolution?
[19:23] <CoJaBo> Some codecs have that limitation; I didn't think x264 was one of them tho...
[19:24] <sponsx> hmm, Im trying to find a solution that takes a wide variety of uploads and converts them to a standard size
[19:24] <sponsx> yeah, adding -s 294x164 resolves the problem
[19:24] <sponsx> not that thats a solution :/
[19:32] <CoJaBo> sponsx: In almost all cases, probably, your height/with is going to need to be an even number. Some encoders and/or codecs are forgiving of that, some aren't.
[19:33] <JEEB> 4:2:0 YCbCr stuff needs to be mod2 (divisible by 2)
[19:33] <JEEB> there should be examples somewhere, either on the trac or the documentation on how to automate it
[19:35] <sponsx> automate?  Like parse the current size and make it even ?
[19:35] <JEEB> nah, you can give the resize video filter basically an algorithm
[19:35] <JEEB> see the example @ http://ffmpeg.org/trac/ffmpeg/ticket/309
[20:04] <roxlu> hi
[20:21] <PowerNET> hello
[20:22] <PowerNET> i'm just wondering if there is a syntax that allows ffmpeg to output multiple files
[20:22] <PowerNET> like lets say i want to output .avi in C: and .avi in D:
[21:08] <creaux> PowerNET: yes, just write both paths
[22:15] <sponsx> Hi, Im trying to use -vf scale= to force my video to be a resolution that is divisible by two
[22:16] <sponsx> I found this: http://ffmpeg.org/trac/ffmpeg/ticket/309  But that just changes my resolution to 854
[22:17] <sponsx> basically I want to changes resolutions like 294x165 to something that can be encoded by x264 like 294x164
[22:19] <JEEB> sponsx, you don't copy the example, you look at what's called in it and change accordingly
[22:20] <JEEB> the post there says exactly what that example does
[22:20] <sponsx> Yeah any reference to the syntax anywhere?
[22:20] <JEEB> also the ffmpeg online documentation has most of the syntax if I recall correctly
[22:20] <JEEB> http://ffmpeg.org/ffmpeg.html#Expression-Evaluation
[22:21] <JEEB> the : given to the scale filter is the delimiter
[22:21] <JEEB> so yes, the example sets the width to a non-changing 854
[22:22] <JEEB> then there's the delimiter, and then there's 'ow' that is original width, and a that is the aspect ratio
[22:22] <JEEB> the explanation of the 'ow' and the 'a' are somewhere, too
[22:22] <JEEB> probably in that same documentation
[22:24] <sponsx> ok
[22:24] <sponsx> thanks
[22:41] <sponsx> "iw:trunc(ow/a/2)*2 is what I needed.  Thanks alot.
[22:47] <JEEB> np
[22:47] <JEEB> also, that doesn't do anything to width
[22:47] <JEEB> so you might want to check that too if you're doing something widely automated
[23:03] <sponsx> k
[23:06] <sponsx> scale="trunc(iw/2)*2:trunc(ih/2)*2"
[23:13] <_Nike_> When I use (avformat_open_input(&context, "rtsp://..." works! when I use: void myfunc (const char *URL)  { avformat_open_input(&context, URL,... } don't work!
[23:30] <PowerNET> so i'm trying to do this: "ffmpeg -i file.avi -vcodec copy -acodec libmp3lame -f avi C:\file.avi -f avi D:\file.avi"
[23:30] <PowerNET> not sure if i can do this
[00:00] --- Sun Jul 22 2012