[Ffmpeg-devel-irc] ffmpeg.log.20140330

[burek]

[10:22] <blockh34d-sleep> is ffprobe available by itself somehow?
[10:23] <blockh34d-sleep> i wrote an app that uses ffprobe for some stuff, seems like overkill to install ffmpeg just for ffprobe
[13:32] <Mavrik> ffmpeg is a tiny binary? O.o
[13:55] <superware> I have an H.264 stream over RTP, and I want to use FFmpeg avlib* to open and dump to a mp4 file, is there a tutorial that demonstrates something similar?
[14:01] <JEEB> look at the demuxing/decoding example under doc/examples
[14:02] <JEEB> although in your case unless you want to re-encode the H.264 stream, you should be able to just use libavformat to demux the RTP stream, and then you can use another libavformat instance to take those packets and mux them into mp4
[14:02] <JEEB> there's most probably a muxing example as well, so take a look at both
[14:07] <superware> ok, thanks
[14:21] <superware> JEEB: couldn't really understand what to use in order to mux into mp4... :|
[14:23] <JEEB> same as for the demuxing of packets
[14:26] <julienb> hello, i have a problem with my server which is rebooting always when i make conversion with ffmpeg
[14:26] <julienb> i would like to know if it can be ffmpeg or other thing?
[14:34] <superware> JEEB: I've successfully opened the network stream, and looping over incoming AVPackets, but how should I open and write to the output file?
[14:36] <superware> I guess it should be quite simple considering there's no decoding envolved
[14:38] <JEEB> I can see a muxing example. That example also encodes a synthetic audio and video stream, but it also contains the basics of muxing
[14:38] <JEEB> doc/examples/muxing.c
[14:51] <superware> JEEB: avformat_alloc_output_context2; add_stream; avcodec_open2; avcodec_alloc_frame; avio_open; avformat_write_header; av_interleaved_write_frame per frame?
[15:13] <superware> JEEB: sorry for nagging, you're probably my only option to do this right :)
[15:15] <CokaCola> bin/ffmpeg -i $1 -acodec pcm_s16le tmp/output.wav --unable to find a suitable output format for 'tmp/output.wav'
[15:15] <CokaCola> any ideas? I even tried just going ffmpeg -i $1 output.wav(also tried .ogg), same problem
[15:52] <superware> JEEB: ?
[15:56] <CokaCola> Weird, it works fine if I run it directly in the console
[15:56] <CokaCola> So somehow running it in a script doesn't work :
[16:46] <dagerik> I used ffmpeg to extract a clip from longer video. However, subtitles seem to be off by default.
[16:46] <dagerik> To enable mplayer I need to hit j to enable it
[16:46] <dagerik> To enable subtitles in mplayer I need to hit j
[17:08] <jnvsor> How do I keep sound in sync when streaming flv?
[17:43] <PKvid> Does anyone know how to create a waveform file like jpg/png with ffmpeg?
[18:07] <blockh34d-zzz> does anyone know of any ffmpeg packages that only include ffprobe and smaller utils like that?
[18:08] <blockh34d> i wrote a little app that uses ffprobe to get some media information, so now people need to install ffmpeg to use it, and it seems like overkill a bit just to get at ffprobe
[18:09] <PKvid> I've got ffprobe
[18:09] <PKvid> what command mus I use?
[18:10] <blockh34d> to what?
[18:10] <PKvid> Does anyone know how to create a waveform file like jpg/png with ffmpeg? Sorry I thought you were talking to me
[18:10] <blockh34d> oh, no i was justtrying to figure out how to reduce my apps install size
[18:11] <blockh34d> i'm confused by waveform file jpg/png
[18:11] <blockh34d> what does that mean?
[18:11] <sacarasc> blockh34d: Why not use the ffmpeg libraries and implement it yourself?
[18:11] <blockh34d> wouldnt users still have to install ffmpeg to install my app then?
[18:11] <PKvid> It is posssible to generate a waveform representation of the audio file
[18:11] <sacarasc> Not if you statically built it!
[18:11] <PKvid> I wondered if it's possible with ffmpeg to save it as an image
[18:12] <sacarasc> Also, packaging is a distro thing.
[18:12] <blockh34d> sacarasc: oh i was wondering about that... am i allowed to redist my compiled app like that? i thought it might be a license problem
[18:12] <blockh34d> am i allowed to redist my app with a static build of ffprobe?
[18:13] <sacarasc> Probably.
[18:13] <blockh34d> btw i dont know much of anything about any of this, in case thats not obvious, just stumbling through it all here
[18:14] <blockh34d> pkvid i use ffmpeg (avconv) to strip audio out of a mpg and save it as a mp3
[18:14] <blockh34d> is that at all what you're trying to do?
[18:14] <sacarasc> They're trying to get an image of the wave form.
[18:14] <sacarasc> Not get the audio.
[18:14] <PKvid> sacarasc Indeed
[18:15] <blockh34d> oh
[18:15] <blockh34d> well thats a little harder i guess, or at least, i dunno how to do that with ffmpeg
[18:15] <sacarasc> Especially as you're not using ffmpeg. :D
[18:16] <sacarasc> #libav is the avconv channel.
[18:16] <sacarasc> Etc.
[18:16] <blockh34d> oh
[18:16] <blockh34d> well i'm pretty confused at this point
[18:16] <blockh34d> i thought ffmpeg and avconv were basically the same project
[18:16] <blockh34d> just new names
[18:18] <blockh34d> oh thanks for that stackof link that explains a bit
[18:19] <blockh34d> fyi raspbian (debian) still shows the weird error message
[18:19] <blockh34d> i think i'd rather use ffmpeg than libav, avconv, etc...
[18:19] <blockh34d> libav sound like... jackasses
[19:10] <PKvid> Does anyone know how to create a waveform file like jpg/png with ffmpeg?
[19:11] <sacarasc> Have you tried reading the manual?
[19:15] <PKvid> Yes, could not find
[19:15] <PKvid> anything
[19:17] <blockh34d> so sacarasc you've got me thinking about making my own playback app and ffprobe-ish app now
[19:17] <blockh34d> how realistic to you think it would be for me to make a mp3 player that once or twice per second, output FFT peak data to stdout
[19:18] <blockh34d> cause i have a player GUI i made (for raspberry pi's omxplayer), and i'd like to be able to have a winamp style eq in it
[19:18] <blockh34d> the gui is atcuatll text mode so tui i guess... all curses and asciiart
[19:19] <JEEB> raspberry pi isn't fast enough to encode AAC with the libavcodec encoder
[19:19] <blockh34d> is that what i'd need to do to get that data?
[19:19] <blockh34d> cuase i think omxplayer does all decoding in hardware
[19:20] <blockh34d> so i dunno that i'd ever have access to the raw decoded data
[19:25] <xlinkz0> I'm trying to capture the screen on windows 8.1
[19:25] <xlinkz0> but "ffmpeg -list_devices true -f dshow -i dummy" doesn't show the screen-record
[19:26] <blockh34d> maybe scrot would work?
[19:26] <blockh34d> i use scrot for screen capture on rpi debian
[19:28] <blockh34d> n/m i guess if you wanted to use scrot you would! lol i didnt even know ffmpeg could record the screen, thats pretty cool
[19:30] <xlinkz0> scrot seems to be linux only :(
[19:30] <blockh34d> ah oh well. surprising there isn't more available options for win 8
[19:30] <blockh34d> i know how to fix this
[19:31] <blockh34d> step 1: remove windows 8.1
[19:31] <blockh34d> forever
[19:31] <blockh34d> step 2: _______
[19:32] <blockh34d> step 3: PROFIT!
[19:33] <blockh34d> well i'm gonna go offtopic rant somewhere else
[19:33] <blockh34d> have a nice day everyone
[19:46] <jnvsor> Guess I'll ask again... How do I ensure video and audio will be synced streaming to twitch from ffmpeg?
[19:54] <klaxa> i don't think you can, what command line are you using? (exclude your stream key)
[19:56] <klaxa> when i get back, i'll see what i can do, afk for now
[20:37] <jnvsor> klaxa: http://pastebin.com/jNRsURhe
[20:56] <xlinkz0> nsfw : http://i.imgur.com/PPSwzlb.gif
[20:56] <xlinkz0> thank you ffmpeg !
[20:56] <xlinkz0> lol
[21:02] <ubitux> is this a boob version of 2048?
[21:34] <superware> I've been trying all day to get an h.264 over RTP into a local mp4 file (no decoding/encoding). I'm reading the stream packets using av_read_frame into an AVPacket. How should I setup the output context? how can I define that av_write_frame won't do any decoding/encoding? only dump..
[21:49] <superware> or.. how should I mux AVPackets (h264/RTP) into mp4 file?
[21:55] <superware> JEEB: can you please help me?
[22:16] <Foxhoundz> I need help
[22:16] <Foxhoundz> ffmpeg won't convert a wave file to mp3 for some reason
[22:16] <Foxhoundz> I've installed libmp3lame
[22:17] <Foxhoundz> I get the following error when running it: Error while opening encoder for output stream #0.0 - maybe incorrect parameters such as bit_rate, rate, width or height
[22:17] <Foxhoundz> and my initial input /usr/bin/ffmpeg -b 192k -i /var/www/drupal-7.26/sites/default/files/drmapan.wav /var/www/drupal-7.26/sites/default/files/drmapan.mp3
[22:18] <Foxhoundz> removing the -b switch doesn't help it either
[22:18] <Foxhoundz> any ideas?
[22:18] <JEEB> you're setting a bit rate for input/decoder
[22:18] <JEEB> -b:a 192k after -i
[22:19] <Foxhoundz> but it didn't work even after removing that switch
[22:19] <JEEB> then it didn't have any good rate control mode set?
[22:19] <JEEB> maybe pastebin the full output and link it here? :P
[22:19] <MaZderMind> Hi all. I have a problem getting stills from anamorphic videos. running `ffmpeg -i http://ftp5.gwdg.de/pub/misc/openstreetmap/FOSSGIS2014/716-h264-hq.mp4 -ss 20 -vframes 1 thumb.png` results in a png with the native pixel numbers, presumably because pngs don't support none-square pixels
[22:20] <MaZderMind> I don't know if all videos are 16:9-anamorphic, some may be 4:3, so I'd like to avoid hard-coding pixel-sizes. all should be in the video-file, ffprobe reports propper DAR of 16:9
[22:20] <JEEB> MaZderMind, https://trac.ffmpeg.org/wiki/Scaling%20%28resizing%29%20with%20ffmpeg
[22:20] <JEEB> see the examples here
[22:20] <Foxhoundz> JEEB: here's the output http://laravel.io/bin/X2VO
[22:21] <JEEB> Foxhoundz, first of all when using libav-based tools you use avconv, not ffmpeg. second of all, try setting that bit rate
[22:22] <klaxa> jnvsor, try to use -r instead of -framerate and move it after -i :0.0
[22:23] <klaxa> maybe someone should update the docs for that, it's a common command and many people run into synchronization issues with it
[22:23] <MaZderMind> JEEB: thank you. I'm not sure I see an example that wil work without knowing the source pixel size.
[22:24] <MaZderMind> all I'm looking for was a capture of the video-fram as ffplay would show it
[22:24] <JEEB> well, you DO know it (as in there's a symbol for the scale filter for both SAR and DAR)
[22:24] <JEEB> and goddamnit
[22:24] <JEEB> you most definitely did not read that page to the end
[22:25] <MaZderMind> JEEB: kk, got me. going to read before coming back :)
[22:25] <JEEB> more here http://ffmpeg.org/ffmpeg-all.html#Examples-10
[22:25] <JEEB> (the last three or so examples in the latter are useful for you as well)
[22:26] <JEEB> and then you can scroll up for the most used parameters you can give the scale filter)
[22:26] <MaZderMind> JEEB: thank you, I wasn't able to google that constant listing. That helps
[22:28] <Foxhoundz> JEEB: The drupal convertor uses ffmpeg so I don't have much choice
[22:28] <JEEB> well you just defined the command line
[22:28] <Foxhoundz> as long as avconv is being aliased as ffmpeg
[22:28] <Foxhoundz> then it shouldn't matter
[22:28] <JEEB> well in 0.8 it isn't
[22:28] <JEEB> it's IIRC the old pre-updated ffmpeg
[22:29] <JEEB> also I do recommend you update your libav if you're going to use it to one of the ones available from the multimedia team's PPA. 0.8 is /old/ , but unfortunately debian didn't finish the migration in time for a newer release to get into 13.10
[22:30] <MaZderMind> thank you, works. have a nice night
[22:30] <JEEB> https://launchpad.net/~motumedia if you're running a server you probably want one of the PPAs giving out the stable version 9 or 10 for your version, not daily builds
[22:31] <JEEB> or you can of course grab FFmpeg ffmpeg from one of the static build places
[22:31] <JEEB> whichever fits your fancy
[22:31] <Foxhoundz> what was bit rate you suggested again?
[22:31] <Foxhoundz> -ab 192k?
[22:32] <JEEB> well, 192k was what you wanted to set :P
[22:32] <JEEB> but yes -ab should work with that old old ffmpeg
[22:32] <JEEB> avconv and newer FFmpeg ffmpeg take -b:a just fine
[22:32] <Foxhoundz> still a no go
[22:32] <Foxhoundz> :(
[22:33] <Foxhoundz> So  I guess I have to upgrade this ffmpeg
[22:33] <Foxhoundz> do you know any PPAs that have the updated ffmpeg binaries?
[22:33] <Foxhoundz> clear
[22:34] <JEEB> no, but you should be able to grab a static binary or so from somewhere linked from ffmpeg.org
[22:41] <Foxhoundz> :D
[22:41] <Foxhoundz> I think it worked!
[22:41] <Foxhoundz> let's see let's see!
[22:42] <esrax> hi guys, using avconv to stream x264 video in mpegts and the receiving end is complaining that the pts isnt changing sometimes
[22:44] <JEEB> avconv comes from the libav project, #libav is the correct channel for it :)
[22:46] <esrax> when i go to use ffmpeg on debian and it tells me ffmpeg is deprecrated, what is that about?
[22:46] <JEEB> it means it's deprecated within the libav project
[22:46] <Foxhoundz> yay it worked!
[22:46] <JEEB> ffmpeg's ffmpeg is separate
[22:46] <sacarasc> It means you're using avconv from libav.
[22:46] <esrax> geez so how do i get the real ffmpeg on debian?
[22:47] <esrax> i'll give that a shot
[22:47] <JEEB> basically when elenril rewrote parts of ffmpeg's option stuff, libav also decided to rename the binary to avconv and leave the ffmpeg binary to wither around until the next release :)
[22:47] <JEEB> FFmpeg merges most of the libav's changes so it contains those, too
[22:47] <esrax> can i expect to see different behaviour between the two?
[22:48] <JEEB> possibly some
[22:48] <esrax> worth a shot then
[22:48] <JEEB> and usually the repository stuff is just old
[22:48] <JEEB> debian didn't finish migration to libav 9 in time for 13.10
[22:48] <JEEB> so basically every ubuntu release from 12.04 to 13.10 contains a libav release from very early 2012
[22:48] <JEEB> which is like... ugh
[22:49] <JEEB> at least the libav 10 migration is now taking less time, although it did miss the 14.04 timeframe
[22:49] <JEEB> so the new LTS will have an already year-old release >_>
[22:50] <esrax> yeah still getting the pts not changing stuff on both the video and audio streams
[22:50] <sacarasc> That Libav decided to go from 0.8.9 to 9 is kinda funny.
[22:50] <JEEB> the third number doesn't really matter, but yeah -- a jump from 0.x to x
[22:51] <JEEB> (´
[22:51] <esrax> yeah i went to setup this relay server on rhel 6.x first and then...well...i know rhel is behind the times n all but wow
[22:52] <sacarasc> ffmpeg 2.3.0 will be 23.0...
[22:52] <sacarasc> Getting into a version race.
[22:52] <JEEB> chrome style
[23:45] <jnvsor> klaxa: You told me to use -r instead of -framerate but this tends to make desync issues far worse - if the device can't keep up then with -r it won't duplicate frames and will desync
[23:46] <klaxa> did you put it behind -i :0.0 like i told you too?
[23:48] <active8> Trying to get my screen grab in mp4 now. I've pasted the 2 commands and then the output of each with a big space in between so it's easier to read: http://pastebin.com/SaMb3Vr8
[23:49] <jnvsor> klaxa: Haven't had time to record a long enough video to see the desync yet
[00:00] --- Mon Mar 31 2014