[Ffmpeg-devel-irc] ffmpeg.log.20120501

burek burek021 at gmail.com
Wed May 2 02:05:01 CEST 2012


[00:00] <burek> shevybear, use some video editor
[00:00] <burek> and not video encoder
[00:53] <cba123> How would I convert video from h264 mkv to h264 mp4 hiprofile AAC (for PS3) with ffmpeg?  I tried this http://pastebin.ca/2142324 but it gave me an empty file.  I'd also like to add something to use all my cpu, since I have an i7.
[00:55] <burek> cba123, if you are going to change your video stream in any way
[00:55] <burek> you cannot use -vcodec copy
[00:56] <burek> further more -sameq is an encoding option, so it doesn't go with -vcodec copy
[00:56] <burek> which just copies the video stream from input to output
[00:56] <burek> what you need are correct encoding options to re-encode your input
[00:57] <burek> for video, most probably it would be -vcodec libx264 -profile high
[00:57] <burek> but for audio, I don't know
[00:57] <burek> can you type ffmpeg -i input,mkv
[00:57] <cba123> I thought it made sense, since my little understanding was that h264 is h264, and mp4 and mkv are wrappers.  But from other reading, that makes sense.
[00:57] <burek> and post your output to pastebin.com
[00:57] <burek> wrappers=formats/containers/muxers
[00:58] <cba123> I think I want aac audio from what I've read, but I'll try what you said.
[00:58] <burek> and h264 = encoder/codec
[00:58] <burek> what is your original audio stream
[00:58] <burek> burek> can you type ffmpeg -i input,mkv
[00:59] <cba123> http://pastebin.ca/2142332
[01:01] <burek> Video: h264 (High)
[01:01] <burek> your video is already properly encoded
[01:02] <burek> ffmpeg -i input.mkv -vcodec copy -acodec aac -strict experimental -ab 128k output.mp4
[01:02] <burek> and to use all your cpus, you would usually add -threads 0
[01:09] <cba123> burek, Seems not to have worked right, just gave me rear channels from the look of it...
[01:10] <burek> oh
[01:10] <burek> ffmpeg -i input.mkv -vcodec copy -acodec aac -strict experimental -ab 128k -ac 6 output.mp4
[01:10] <burek> try that
[01:12] <cba123> Trying it now, seems to be going fast enough too.  Thanks again
[01:12] <aphid> not having to encode video definitely speeds things up
[01:14] <cba123> Yeah, I also threw the threads 0 in the front, before -i.  Seems to work.
[01:14] <cba123> Now, is there a way I can get it to work on all the mkv's in a folder, so I don't have to manually do it?
[01:19] <cba123> burek, Maybe I had the wrong info?  Because when I put the drive to my PS3, it doesn't see the files, even when I do "show all"
[01:19] <cba123> burek, Nevermind, took it a second to find it
[01:24] <cba123> burek, The audio still seems off, a little bit in, it gets choppy, idk why though
[03:52] <Shimmy> Everyone please follow: http://area51.stackexchange.com/proposals/40292/ffmpeg
[05:25] <elkng> is "mediainfo" better than "ffprobe" ?
[10:12] <APoulos> hey Burek!
[10:13] <APoulos> ah, I'll come back later
[10:13] Action: APoulos is away: Away
[12:44] <BlackBishop> I'm wondering .. is there any way I could re-stream some stuff from a http:// stream to my local network ?
[12:50] <westwind> Does the ffmpeg have plan to add support for some hardware based video decoder?
[12:51] <westwind> such as chip&media
[12:51] <zap0> i doubt it.
[12:51] <zap0> adding hardware dependancies is bad mmmmkay
[12:54] <JEEB> I think ffmpeg already has support for DXVA2
[12:54] <JEEB> not sure about other hwaccels
[12:57] <westwind> does the ffmpeg define the hardware acceleration abstraction layer?
[12:58] <BlackBishop> I don't get it .. how the heck can I make ffserver get mpeg2video/mp2audio and re-stream it to my network in the same format ! :|
[12:58] <JEEB> BlackBishop, pretty much no-one gets ffserver :P
[12:58] <JEEB> you'll be better off just restreaming it off with VLC's streaming functions
[12:59] <JEEB> if you need something easy-to-use
[12:59] <BlackBishop> ahm .. :) vlc it'll be then ! :)
[12:59] <JEEB> ffserver is "have some archaic stuff that only X people can use, and you can keep both pieces if it breaks."
[13:00] <JEEB> I'm not sure if ffmpeg itself can output to http
[13:01] <BlackBishop> ffserver -d -f ~/ffserver.conf & ffmpeg -v 2 -r 5 -s 640x480 -f video4linux2 -i /dev/video0 http://myip:3343/webcam.ffm
[13:01] <BlackBishop> seems to work for my webcam :)
[13:02] <BlackBishop> wth .. I thought any port > 1024 can be opened by a normal user :/
[13:03] <_raven> hi
[13:03] <BlackBishop> [00000435] access_output_http access out error: cannot listen on myip port 10001
[13:03] <_raven> how to combine/splice two video files? cat|ffmpeg?
[13:03] <westwind> I heard that the ffmpeg team was divided into two branches? is it ture?
[13:04] <zap0> no.
[13:07] <_raven> hi
[13:07] <_raven> how to combine/splice two video files? cat|ffmpeg?
[13:07] <TooMuchCaffeine> Morning. I need to convert and watermark video for web. and have few questions. what is the optimal way to do it performance and quality wise: a) do it at the same time (convert and overlay); b) convert first then overlay; c) at which point to overlay with 2-pass conversion ???
[13:13] <relaxed> TooMuchCaffeine: a, or c if you need a better average bitrate or specific file size.
[13:20] <TooMuchCaffeine> relaxed: thank you.
[13:27] <westwind> Is there a planning to use the fixed point for all the audio decoders.
[16:03] <benjr> im trying to use ffmpeg for the first time and i get "Unsupported codec for output stream", its h264, what do i have to do to add support for that?
[16:04] <sacarasc> You'll need to compile with libx264 and use libx264 as the codec.
[16:08] <benjr> can i just use my package manager and install libx264?
[16:08] <sacarasc> If it didn't bring it in with ffmpeg already, no.
[16:09] <benjr> it installed these "ffmpeg libavdevice52 libavfilter0" and i already had libx264-120 installed it seems
[16:09] <sacarasc> Try using the libx264 codec, then.
[16:11] <benjr> my command is ... ffmpeg -sameq -ss 00:00:00 -t 00:00:30 -i "$file" "edited/$file"
[16:11] <benjr> just wanting to cut part of the video, not re-encode, thats why im using sameq,
[16:12] <sacarasc> Remove -sameq.
[16:12] <sacarasc> Add -vcodec copy and -acodec copy to the output options.
[16:14] <benjr> ah perfect, works a charm, thank you very much :)
[16:42] <Randomage> Hey.
[16:43] <Randomage> Quick question, I'm writing a script that uses ffmpeg, and when I feed him very small mp3 files (to be converted into ogg for use in web pages) I get these errors:
[16:44] <Randomage> [mp3 @ 0x9dee380] Cannot read BOM value, input too short
[16:44] <Randomage> [mp3 @ 0x9dee380] Error reading frame TALB, skipped
[16:44] <Randomage> with the resulting .ogg file being unusable.
[16:46] <Randomage> At lease Opera can't handle them.
[16:46] <Randomage> *least
[16:46] <Randomage> Chrome seems to be able to.
[16:52] <TooMuchCaffeine> I have filter_complex/map question. trying to overlay image. however i lose audio stream. i know i need specify it somewhere but don't quite understand where. i exec: ffmpeg -y -i sample.mp4 -i wm.png -filter_compelx 'overlay[out]' -map '[out]' out.m4v
[17:11] <mads-> Can anyone tell me how I would take an avi file and a part of it from fromTime to endTime and then safe it as a gif?
[17:13] <TooMuchCaffeine> mads-: ffmpeg -i <input> -ss <start from> -t <duration> <output>
[17:13] <mads-> TooMuchCaffeine, I have searched google thin for this, and that just seems so simple. Somehow I can set the framerate as well?
[17:14] <TooMuchCaffeine> mads-: put ss & t before input
[17:15] <TooMuchCaffeine> ffmpeg -ss <start> -t <duration> -i <input> -r <framerate> <output>
[17:26] <TooMuchCaffeine> ffmepg -help (cf. x264 --fullhelp). how do i view the 'fullhelp'?
[17:36] <TooMuchCaffeine>  I have filter_complex/map question. trying to overlay image. however i lose audio stream. i know i need specify it somewhere but don't quite understand where. i exec: ffmpeg -y -i sample.mp4 -i wm.png -filter_compelx 'overlay[out]' -map '[out]' out.m4v
[18:41] <wwalker> I want to take a file (.mov) with a h.264 video and two audio channels and just delete one of the audio channels  , no transcoding, which options do I read about in the man page?
[19:04] <thang> hi all, im trying to encode to vp8 on an ec2 instance and followed the instructions here: http://ubuntuforums.org/showpost.php?p=9868359&postcount=1289 but im getting a segfault every time. the log file looks like so: http://pastebin.com/fsEFd2zY and ive tried various source files. this was also on a clean install of 10.04. what can i do to investigate this further?
[19:05] <Kuukunen> wwalker: -map
[19:45] <wwalker> Kuukunen: thank you!
[19:52] <ashka> hello, I'm trying to set up a stream to twitch
[19:54] <ashka> I ended up there : ffmpeg -f x11grab -s "1680x999" -r 35 -i :0+0,0 -itsoffset 00:00:01 -f alsa -ac 2 -i pulse -vcodec libx264 -s 1680x999 -acodec mp2 -ab 96k -threads 6 -qscale 5 -b 1024k -f flv "rtmp://live.justin.tv/app/my_secret_stream_key" but when I start it it waits for a few seconds and then it says Error while opening encoder for output stream #0.0 - maybe incorrect parameters such as bit_rate, rate, width or height
[19:55] <Mavrik> there's another error in your output you're missing.
[19:58] <ashka> Mavrik: I've been searching for a while
[19:58] <ashka> I haven't found anything
[19:59] <Mavrik> paste your output as the channel guidelines say.
[20:06] <ashka> actually, I got a little further
[20:06] <ashka> twitch says that I stream, but no image and no audio, I'm pasting
[20:07] <ashka> http://pastebin.com/ibCahQAb
[20:10] <Mavrik> wow
[20:10] <Mavrik> why are you using ffmpeg from stone age?
[20:11] <Mavrik> and 2.) why are you using mp2 as an audio format?
[20:11] <Mavrik> is that even supported by flv and flash players?
[20:13] <ashka> I use a OS from the old ages ;)
[20:14] <taqattack> is there a way to output constant fps to rtmp stream?
[20:14] <ashka> currently updating that
[20:17] <Mavrik> ashka: basically, newer ffmpeg (use at least 0.10.1) should give you more meaningful messages
[20:17] <Mavrik> ashka: and if you're streaming H.264 keep to AAC audio
[20:18] <ashka> Mavrik: actually I followed some kind of tut, that said to stream in flv
[20:18] <ashka> but it didn't worked, because of my old-aged ffmpeg I guess
[20:18] <Mavrik> yeah
[20:18] <ashka> (no flv output muxer, something like that)
[20:18] <Mavrik> but putting MP2 in flv...
[20:21] <thang> update on my problem: the -deinterlace flag seems to be causing the segfault; and its been deprecated, doh
[20:22] <Mavrik> thang: -vf yadif is the "canonical" way to do deinterlacing now
[20:23] <thang> yeah i saw in the faq, thanks Mavrik everything seems to be working now.
[20:34] <ashka> hmm
[20:34] <ashka> I'm having trouble compiling ffmpeg
[20:34] <ashka> http://pastebin.com/E1ukZ3p9
[20:39] <thang> ashka: this is a shot in the dark, did you compile x264 from source, and does anything show up for dpkg -l x264 ?
[20:39] <ashka> source, but I forgot --enable-shared ;)
[20:44] <ashka> hmm
[20:44] <ashka> that is weird
[20:44] <ashka> Unrecognized option 'directpred' /usr/share/ffmpeg/libx264-medium.ffpreset: Invalid option or argument: 'directpred=1', parsed as 'directpred' = '1'
[20:44] <ashka> is that a actual bug ? or did the make install did not copy the new presets ?
[20:45] <Mavrik> there are no more preset files anymore
[20:45] <Mavrik> the presets are built-in to x264 now - you're not supposed to use those anymore
[20:46] <Mavrik> replace "-vpre" in commandline with "-preset"
[20:46] <ashka> oh, okay
[20:46] <Mavrik> :)
[20:47] <ashka> Mavrik: I got the more obvious messages you wanted
[20:48] <ashka> http://pastebin.com/9hmNY3pg
[20:48] <ashka> hm nvm
[20:48] <ashka> I just read that
[20:49] <ashka> now I have something interesting
[20:50] <ashka> [libmp3lame @ 0x1b45de0] flv does not support that sample rate, choose from (44100, 22050, 11025). > how do I set that rate ?
[20:51] <ashka> (it's the same command as in the paste)
[20:51] <sacarasc> -ar
[20:51] <sacarasc> As an output option.
[20:59] <ashka> this seems to be working
[20:59] <ashka> but I have some cuts though
[20:59] <ashka> 2-3 seconds
[20:59] <ashka> my connection is not laggy at all, I just tested it, it's fine
[21:14] <ashka> hm, that's quite working
[21:14] <ashka> but I have a problem, the FPS are still decreasing over time
[21:53] <Shimmy> http://area51.stackexchange.com/proposals/40292/ffmpeg
[22:58] <burek> Shimmy, regarding this issue of yours http://pastebin.com/ieL8UUFG
[22:58] <burek> remove -vtag
[22:59] <burek> and also, when you specify -s you don't need -aspect
[22:59] <burek> and vice versa
[23:04] <burek> and also, if you really want exactly the same encoding results, you can use
[23:04] <burek> Writing library                          : XviD 1.1.2 (UTC 2006-11-01)
[23:05] <burek> so, join xvid support channel, provide them with pastebin info for mediainfo about native.avi
[23:05] <burek> and they can tell you what params to use to encode another video in the same fashion (or ask mencoder guys, whose software created the original file native.avi)
[23:33] <burek> Shimmy, ping
[23:34] <Shimmy> burek, yes. When including -vtag XVID, the video plays in fast motion for several seconds, then i see an error msg on device.
[23:34] <burek> Shimmy, do you know what you did using -vtag?
[23:38] <burek> try creating one video with -vtag and one without it
[23:38] <burek> and compare the output of ffmpeg -i file.avi
[23:38] <burek> for both
[23:38] <burek> pay attention to: Stream #0:0: Video:
[23:38] <Shimmy> burek, i believe it's forcing XVID to be the video tag (as in native.avi). The truth is i copied that line from here: http://forums.creativecow.net/thread/291/686
[23:38] <burek> Shimmy, that's wrong
[23:39] <burek> -vcodec sets appropriate -vtag
[23:39] <Shimmy> gimme a sec
[23:39] <burek> -vtag is only used for special purposes/testing and such things
[23:39] <burek> and should never be used in normal situations
[23:41] <Shimmy> Here are the differences:
[23:41] <Shimmy> native.avi: Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658), yuv420p, 160x128 [SAR 1:1 DAR 5:4], SAR 65536:65535 DAR 16384:13107, 15 tbr, 15 tbn, 15 tbc
[23:41] <relaxed> Shimmy: yes, that what it does. try ffmpeg -i avisample.avi -vtag XVID -vcodec libxvid -s 160x128 -aspect 5:4 -b:v 277k -r 15 -acodec mp2 -ar 44100 -ac 2 -ab 128k output.avi
[23:41] <Shimmy>     Stream #0:0: Video: mpeg4 (Simple Profile) (xvid / 0x64697678), yuv420p, 160x128 [SAR 1:1 DAR 5:4], 15 tbr, 1 15 tbc
[23:41] <relaxed> er, I hit enter :/
[23:42] <burek> Shimmy, notice the hex code after XVID and xvid.. Do you see it's different
[23:42] <burek> practically you have 2 different video codecs specified
[23:43] <burek> SAR 65536:65535 DAR 16384:13107 ? isn't that a little bit odd..?
[23:43] <Shimmy> relaxed, i'll try that in a second
[23:44] <relaxed> Shimmy: -vf scale=160:128 -vcodec mpeg4 -b:v 277k -vtag XVID -acodec libmp3lame -b:a 128k
[23:44] <Shimmy> burek, that hex was when i omit the vtag, if i include the -vtag XVID, the hex is the same:  Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658)
[23:45] <Shimmy> burek, yes it is. i don't know what it means
[23:45] <Shimmy> relaxed, u confused me, what belongs where
[23:45] <burek> Shimmy, let's put it this way. Coca-Cola takes a bottle, fills it with Coca-Cola juice, closes it and puts the Pepsi sticker on the bottle
[23:46] <burek> that's what you did with -vtag
[23:46] <Shimmy> burek, u might be and probably right, but this is actually making a difference on the device
[23:47] <burek> I know it does, but your device is trying to read XVID content instead of xvid content and that's where the problem will definitely occur
[23:47] <burek> you need to find the way to do it without using -vtag
[23:48] <Shimmy> burek, u mean by adjusting that odd DAR SAR 65536:65535 etc.
[23:49] <burek> by adjusting all the necessary encoder options, just like what's been used to produce native.avi
[23:49] <mbradshaw> DAR/SAR shouldn't have anything to do with the -vtag. DAR/SAR just refer to the Display/Sample Aspect Ratio for the pixels
[23:49] <Shimmy> burek, i first wanna make it work no matter how, then will try to make it the proper way
[23:51] <burek> Shimmy, what's the device model
[23:53] <Shimmy> burek, why?
[23:53] <burek> so that I can see what format does it support
[23:53] <burek> and suggest you with the correct encoding options
[23:54] <Shimmy> relaxed, the first line of yours (00:41) doesn't work, it's still fast motion and raises error msg on device withing several seconds of playback.
[23:54] <Shimmy> burek, im sure you're not gonna find a thing.
[23:56] <Shimmy> burek, actually i found this page: http://www.bhphotovideo.com/c/product/686688-REG/Impecca_MP_1827W_MP1827_Digital_Media_Player.html
[23:56] <Shimmy> which says that the device can play amv.
[23:56] <Shimmy> i think i have an amv file that works on the device
[00:00] --- Wed May  2 2012


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