[Ffmpeg-devel-irc] ffmpeg.log.20121211

[burek]

[00:07] <k333d> i know there's a command for cutting media without re-encoding in ffmpeg, is there a way to feed that command scene change detection information so that ffmpeg can cut a movie file up into a bunch of scenes?
[00:18] <k9d> sorry, got disconnected so reposting my q:
[00:18] <k9d> i know there's a command for cutting media without re-encoding in ffmpeg, is there a way to feed that command scene change detection information so that ffmpeg can cut a movie file up into a bunch of scenes?
[00:25] <klaxa> k9d: look at the -ss and -t parameters
[00:27] <k9d> klaxa: thanks, i'm familiar w/ -ss for setting the seek position, but is there a way to generate a list of scene changes, then do seeks to them to chop them out?
[00:27] <klaxa> not really
[00:27] <klaxa> there are algorithms for scene change detection, they are never reliable though
[00:27] <klaxa> it's a heuristic procedure
[00:28] <ubitux> you have access to a scene detection filter, and to a segmenter output
[00:28] <ubitux> but linking both might need some custom code from your side
[00:30] <brx_> hey can an ffmpeg expert please take a look at this question I have regarding encoding mp4s for android http://pastebin.com/g5YeDbGF
[00:38] <k9d> klaxa: ubitux: i'm ok w/ the procedure not being reliable. it's for an art project so i just need to chop a larger movie in to much smaller sections is the scene detection filter something built into ffmpeg or is it another software?
[00:39] <ubitux> it's built-in, but it will just help you pick or locate a scene change frame
[00:40] <ubitux> not a "segment"
[00:40] <ubitux> http://ffmpeg.org/ffmpeg.html#select
[00:40] <ubitux> look for "scene" here
[00:41] <k9d> ubitux: ah, ok, then i need a timestamp of the frame that command generates, and if i make a big list of those i'll have all my start/end points for segments
[00:41] <ubitux> yes, something like this
[00:46] <kevinday> hey ffmpeg people, is there somewhere a list of ffmpeg developers who are interested in doing paid work? (i.e. we pay to get something fixed/added in ffmpeg)
[00:47] <klaxa> https://www.ffmpeg.org/consulting.html
[00:47] <klaxa> or so i guess?
[00:48] <kevinday> how did i look at the ffmpeg page so many times and not see that
[00:48] <klaxa> dunno
[01:09] <bakers> I have an MKV I want to convert lossless to mp4... easy enough. When I do that I lose the subtitles that are built in to the MP4
[01:09] <bakers> when I try and do "-scodec copy" and I get [mp4 @ 0x2afe340] track 2: could not find tag, codec not currently supported in container
[01:11] <Mavrik> bakers: yeah, your subtitles are in the wrong format.
[01:12] <bakers> Mavrik:     Stream #0:2(eng): Subtitle: subrip
[01:12] <bakers> What format should I use for mp4?
[01:12] <Mavrik> hmm
[01:12] <Mavrik> interesting
[01:13] <bakers> Mavrik: This is the ffprobe output http://www.fpaste.org/EOor/
[01:13] <ubitux> bakers: -c:s mov_text
[01:15] <Mavrik> btw, while we're at the subject of subtitles
[01:15] <Mavrik> does ffmpeg have a filter to resample dvb subtitles?
[01:15] <bakers> ubitux: That worked!
[03:23] <ffmpeg-noob> Hello, I have been trying to use ffmpeg and have been seeing an error for, unable to parse option value as image size. I pasted the command and output here: http://pastebin.com/kwkKAb77 Can anyone tell me how to correct this?
[03:25] <ubitux> mmh
[03:25] <ubitux> ffmpeg-noob: does it happen if you remove the -vf?
[03:25] <ubitux> i mean the -filter
[03:27] <ffmpeg-noob> That's odd .. I get a different error. complaining about how subs.ass does not exist, but it very clearly does.
[03:28] <ubitux> i meant remove -filter ass=...
[03:28] <ubitux> not just the -filter option, its argument as well :p
[03:29] <ffmpeg-noob> the whole point of my experiment is really to successfully use ass  subtitles though, I can try it, but it kinda defeats my purpose
[03:29] <ubitux> ok get it, i can reproduce
[03:29] <ubitux> replace -filter with -vf
[03:29] <ubitux> in your original cmd line
[03:29] <ffmpeg-noob> sure
[03:30] <ubitux> it seems there is a bug with -filter
[03:30] <ubitux> -filter:v should work as well
[03:30] <ffmpeg-noob> sweet, the encoding has kicked off
[03:30] <ffmpeg-noob> thanks a lot
[03:30] <ubitux> great
[03:30] <ubitux> i hope i'll be able to watch next naruto soon then ;)
[03:31] <ffmpeg-noob> :D
[03:31] <ubitux> (though, hardsub is evil)
[03:31] <ffmpeg-noob> I agree >.>
[03:32] <ffmpeg-noob> but this is for a portable device
[03:32] <ubitux> :)
[03:48] <ubitux> ffmpeg-noob: i just opened a ticket for the -filter bug, #2012
[03:49] <ubitux> easy to remember.
[03:57] <ffmpeg-noob> Great, thanks for that. As an engineer myself, I appreciate things moving down the pipeline.
[03:59] <ubitux> :)
[05:35] <cellofellow> can someone help me compile ffmpeg into a staticly linked binary I can run on a host?
[05:57] <Demon_Fox> Anyone know of a subtitle editor?
[06:06] <cellofellow> Demon_Fox: gnome-subtitles is useable.
[06:06] <cellofellow> subtitleeditor too
[06:07] <Demon_Fox> thanks
[06:07] <Demon_Fox> according to google subtitleeditor looks pretty good.
[06:07] <Demon_Fox> I think I will use it.
[08:01] <Sashmo1> hey everyone, quick question, I've been encoding live TS streams for a while now, and I think its time to smooth out my output, I can see a little freezing in the output, its not freezing, its looks almost like a frame rate issue, but its most noticeable when there are scrolls at the bottom of the screen, anyone have some ideas? http://pastebin.com/rTJZPYg5
[09:27] <pierre-olivierro> Is someone present for some libx264 questions ? -preset -tune -profile
[11:17] <mpfundstein> hello. has anyone here good experience with the down converting 29.95 fps to 25fps on a software basis ?
[11:18] <retard_> i have bad experience with it
[11:25] <germanstudent> hey, i'm quite frustrated with command line id3 taggers. Is it possible to manipulate audio id3 tags with ffmpeg without encoding again?
[11:27] <mpfundstein> @retard what software did you try?
[11:40] <siganderson> I would like to apply a watermark to a ffserver's video stream. Any help? I can already do this with files but not with streams.
[13:54] <MessedUpHare> Hi All, I'm trying to figure out how to control GOP structure using ffmpeg, and i'm a little confused as to which flags i require.
[13:54] <MessedUpHare> I would like to create an mxf wrapped mpeg-2 with the GOP structure of IPB, with a length of 12
[13:55] <mateo`> MessedUpHare: you can try -g 12 -bf 2
[13:56] <MessedUpHare> mateo: this appears to create a file with IBBPBBPBBPBB, where i'd be after IPBPBPBPBPBPB
[13:56] <MessedUpHare> Thanks for the suggestion, though
[13:57] <mpfundstein> as far as i know you cant control this yet
[13:58] <mpfundstein> you can try ffmbc. we generated CableLabs VOD ts files with it using a gop length of 12 and IBBP structure
[13:59] <MessedUpHare> mpfundstein: Thanks, I'll have another look at ffmbc
[14:00] <mateo`> does ffmbc let control the gop structure ?
[14:02] <mpfundstein> not really to be honest but with -g 12 and -bf 2 you get a nice looking structure
[14:02] <mpfundstein> :-)
[14:03] <mpfundstein> you can also try the Open Broadcast Encoder (obe-vod) . We use it also for mp4 ts streams.
[14:03] <MessedUpHare> i'll have a look at that also
[14:03] <MessedUpHare> thanks again
[14:03] <XATRIX> Hi guys, i have a problem
[14:04] <XATRIX> I have a script that generates the mp3 files, and i have to concat them into one mp3 file
[14:04] <mateo`> mpfundstein: you should get the same with ffmpeg
[14:04] <XATRIX> file1+file2+fileN.... = result_file.mp3
[14:05] <XATRIX> So i do the following, and it actually works, it gives the result mp3 file back to me, but it can only glue 3 files
[14:05] <XATRIX> http://hastebin.com/kikorepege.rb
[14:08] <XATRIX> If i play the mp3 files one by one, it does it well.. But if i play my catenated mp3 file, it does the sound from 1.2.3 but the 4th file's sound is not in
[14:13] <IamTrying> How to make it faster, its like Camel slow stream in the receiver. Very very very very very very slow stream the more higher resolution i apply it becomes more slowest.
[14:13] <IamTrying> ffmpeg -f video4linux2 -s 320x240 -r 16 -i /dev/video0 -f oss -i /dev/dsp -g 52 -acodec libvorbis -ab 64k -vcodec libvpx -vb 448 -f webm ....lin...k
[14:19] <XATRIX> So, can anyone advice me something ?
[14:19] <XATRIX> http://hastebin.com/kikorepege.rb
[14:29] <jivetalking> has anyone ever used ecasound for multitrack record with ffmpeg?
[14:30] <jivetalking> so capture audio with ecasound and video with ffmpeg
[15:02] <mpfundstein> df -h
[15:12] <burek> guys did you see the petition that 120,000 people from texas signed that says they want to get out of US union? :) (it's offtopic i know, I'm just surprized with this news)
[15:14] <retard> they want to be part of mexico instead?
[15:14] <retard> maybe rename it texico
[15:14] <mpfundstein> lol
[15:15] <mpfundstein> but austin will stay us
[15:22] <iive> burek: afaik petition could be signed by everybody in usa and I bet that there are more people than that in texas. I don't really think they would want to separate from the other states.
[15:23] <blez> it's strange cause of the north american union
[15:23] <blez> how they'll keep the whole idea the same if they split
[15:34] <ofer> hey there! Question: there is the following command: ffmpeg -i input -s 1600x900 output
[15:34] <ofer> how do I input only width or only height and have the original aspect ratio kept?
[15:35] <burek> use -1
[15:35] <ofer> I see that typing "... -s 1600" or "... -s 1600x" or "... -s x900" won't work
[15:36] <ofer> like this: ffmpeg -i input -s 1600x-1 output
[15:36] <ofer> ?
[15:36] <burek> ffmpeg -i input -vf "scale=-1:360" output
[15:37] <ofer> what is the :360 part?
[15:37] <burek> height
[15:38] <ofer> and if I want to use only width it'll be: ffmpeg -i input -vf "scale=1600:-1" output ?
[15:45] <mpfundstein> scale=1600:iw
[15:45] <mpfundstein> input_width
[15:45] <mpfundstein> you can also do scale=iw*2:ih for example
[15:46] <burek> that will not keep the aspect ratio, obviously
[15:58] <ofer> ha, I see. so iw and ih keep the original width/height, but to keep aspect ratio (so that the picture won't be stretched) I need to use -1. So I guess "scale=1600:-1" should work, right? I'll go ahead and try it :)
[16:19] <mpfundstein> dont know actually
[16:19] <mpfundstein> but to stretch and keep the ar dont u need to add black bars?
[18:27] <siganderson> I would like to apply a watermark to a ffserver's video stream. Any help? I can already do this with files but not with streams and I don't know if this "bug" could be avoided
[18:30] <klaxa> also does a raw h264 file contain metadata headers? if not, how can i extract the raw h264 stream from an mkv with ffmpeg? i get metadata if extracting with ffmpeg -i file.mkv -c:v copy -f h264 file.h264
[18:42] <DorianMeadMug> hey guys, I have a quick question about ffmpeg presets! anyone willing to help?
[18:43] <smj> DorianMeadMug: give it a try
[18:43] <DorianMeadMug> I've been googling for a while but can't seem to find the answer
[18:43] <klaxa> we don't even know the question
[18:43] <DorianMeadMug> how do I set up video filters (i.e. vf's) in a preset file=
[18:43] <DorianMeadMug> *?
[18:44] <siganderson> klaxa, http://pastebin.com/SMHNSNMQ
[18:44] <DorianMeadMug> for example, I have a bunch of videos which need to be cropped to 4:3, and then scaled down to 640x480
[18:44] <DorianMeadMug> I know the vf syntax in command line, but I don't know how to put it in a preset
[18:45] <DorianMeadMug> I tried putting the line like "vf=crop=in_h*4/3:in_h" in the .preset file, but ffmpeg just ignores it
[18:45] <DorianMeadMug> while in command line, -vf crop=in_h*4/3:in_h" works fine.
[18:45] <DorianMeadMug> halp :(
[18:46] <klaxa> siganderson i assume you are using ffserver then? can you try to apply the watermark in the ffserver configuration file? it gets reencoded for each stream, no?
[18:47] <smj> I thought preset files were only for encoding settings, but I'm not an expert
[18:47] <DorianMeadMug> I don't know if they are :-/ I'm no expert either. so I can't put a vf in it?
[18:49] <siganderson> klaxa, of coure, I'm using ffserver, I could try if I knew the way to do it... I don't see anything helpful in the documentation
[18:52] <smj> DorianMeadMug: can you use a simple script instead?
[18:55] <DorianMeadMug> smj: I'll have to, it seems.
[18:55] <DorianMeadMug> anyone else got an idea? also, may I ask why is it so that filters cannot be put into a preset file?
[19:01] <siganderson> klaxa, do you know about some option to specify the watermark in the ffserver's configuration file?
[19:01] <klaxa> i'm afraid i don't
[19:07] <smj> https://sites.google.com/site/linuxencoding/x264-ffmpeg-mapping DorianMeadMug I think the parameters in the file are just passed to the encoder
[19:10] <DorianMeadMug> smj okay, so how come the vf parameters aren't passed to the encoder then?
[19:10] <smj> ffmpeg does filtering and libx264 does encoding
[19:11] <DorianMeadMug> hmm... I see.
[19:12] <DorianMeadMug> so I'll have to write a script myself.
[19:12] <DorianMeadMug> ah well. wouldn't be the first sh script I ever wrote (hopefully not the last either) :D
[19:12] <DorianMeadMug> btw, do you know of any good gui (qt/gtk) frontends for ffmpeg?
[19:12] <DorianMeadMug> for Linux, ofc
[19:14] <klaxa> blasphemy! ffmpeg belongs to the command line D:
[19:14] <DorianMeadMug> ...alright, alright.
[19:14] <klaxa> http://code.google.com/p/qwinff/
[19:14] <klaxa> maybe that's what you're looking for?
[19:15] <klaxa> also looks like there is winFF for linux http://www.linuxjournal.com/video/gui-ffmpeg
[19:15] <DorianMeadMug> aaaaawwwwww this one looks UBER CUTE!!!
[19:15] <DorianMeadMug> the qwinff I mean.
[19:18] <DorianMeadMug> I'm off. Thanks guys! :)
[19:41] <llogan> siganderson: you should be using -filter_complex, not -vf with multiple inputs (such as overlays)
[19:41] <llogan> although i have no ffserver experience. i don't know why it doesn't appear to work for you in your first example.
[19:41] <llogan> and you failed to include the console outputs as fflogger bot mentioned
[20:03] <siganderson> llogan, if I use filter complex I get this error: http://pastebin.com/Fqgv97pj   can I do anything?
[20:05] <llogan> siganderson: does it work with a file output?
[20:06] <siganderson> llogan, yes, with a file output I obtain a video with the image correctly applied
[20:08] <llogan> looks like it's attempting to turn the overlay into an additional video stream. i guess. i dont' know.
[20:09] <siganderson> llogan, is there another way to obtain what I would like to do?
[20:10] <llogan> perhaps ask on ffserver-user mailing list.
[21:25] <tm512> Hi, I'm trying to record the audio from a device that snd_aloop (alsa loopback) provided, but I am getting "[alsa @ 0x6dc320] cannot set sample format 0x10000 2 (Invalid argument)"
[21:26] <tm512> running ffmpeg as: ffmpeg -f alsa -ac 2 -i hw:Loopback,1 /tmp/looptest.wav
[21:34] <dakta> I have a simple task: display all metadata for a given inputfile. Can one of y'all confirm that should just be "ffprobe <inputfile>" ?
[21:36] <dakta> Shouldn't "ffmpeg -i inputfile" work?
[21:37] <tm512> http://hastebin.com/daxojujope
[21:37] <llogan> dakta: both should work. ffprobe gives additional output printing formats
[21:38] <llogan> -print_format <format>
[21:38] <llogan> tm512: is that the complete console output?
[21:39] <tm512> from ffmpeg, yes
[21:39] <dakta> llogan: My problem is that the Metadata section is entirely missing, despite the files having metadata. Both commands just output version info then Duration and Stream sections, but no Metadata section
[21:39] <tm512> snd_aloop creates the Loopback card, and device 1 is an input device that echos what is put into device 0
[21:40] <tm512> running my program using Loopback,0 as the output device
[21:40] <tm512> I'll be right back
[21:42] <dakta> llogan: yeah, yeah, I figured that was coming, here's your paste link: http://pastebin.com/tfkLafxM
[21:43] <llogan> FFprobe version SVN-r92
[21:43] <llogan> absolutely ancient
[21:43] <llogan> ffprobe is now part of FFmpeg
[21:44] <dakta> I blame Debian package maintainers :)
[21:44] <llogan> I also blame them.
[21:44] <dakta> So, is my best bet here to upgrade ffmpeg?
[21:44] <llogan> but you can compile
[21:45] <dakta> yep, that's what I was afraid of...
[21:45] <llogan> or try a static build
[21:45] <saste> dakta, which version of debian are you running?
[21:45] <saste> afaik ffprobe is no more packaged in recent debian (maybe since at least two years)
[21:46] <dakta> saste: I don't actually know. This is Debian on a tiny PPC chip inside a home network hard drive from WD. Recently purchased.
[21:46] <llogan> i don't know if the static builds contain ffprobe, however
[21:47] <dakta> I've heard Lenny and the version after lenny... I don't normally use Debian.
[21:47] <dakta> llogan: Maybe if I described what I'm trying to accomplish you might have some advice for how best to spend my energies.
[21:47] <llogan> cat /etc/debian_version
[21:47] <dakta> 6.0.6
[21:48] <llogan> "Squeeze"
[21:48] <dakta> That's the name I was trying to remember
[21:48] <tm512> I'm back
[21:49] <tm512> why is ffmpeg unable to set the "sample format" when I try recording from that input device
[21:50] <saste> dakta, yes it was released almost two years ago, and Debian release are usually outdated at the moment of the release, so yes makes sense
[21:51] <dakta> So, what I'm really trying to accomplish here is to fix a bug with an iTunes server software, which relies on ffmpeg, which is ignoring the "gnre" metadata atom, resulting in almost all of my music library being categorized as "unknown genre". I've tracked this bug down to an old ffmpeg bug where the "gnre" metadata atom wasn't being read correctly, thus why I'm trying to use ffmpeg to read the files' metadata.
[21:52] <dakta> The bug is reported here, and is supposedly fixed in recent versions of ffmpeg: https://github.com/jasonmc/forked-daapd/issues/76
[21:52] <llogan> your first step is to try a recent ffmpeg or ffprobe. of course option changes and such can cause it to not work with your software.
[21:52] <llogan> or supply a sample and i can give you an output
[21:53] <llogan> if that would be easier
[21:53] <dakta> Sample music, just a sec while I upload.
[21:54] Action: llogan hopes it is not Kenny G.
[21:56] <dakta> llogan: I picked the nearest song in the filesystem, which happened to be "Nonpareil of Favor" by Of Montreal.
[21:57] <tm512> The solution for me was to use plughw:Loopback,1 instead
[21:57] <tm512> so it seems to be all working now
[21:57] <dakta> tm512: glad to hear you have it solved
[21:57] <tm512> it's possible to have the same instance of ffmpeg write two files at once, right? one audio and one video?
[21:58] <dakta> Now, we wait for my slow-ass and peculiarly constricted internet connection... SCP starts at 10MB/s and has now decreased to a steady 50KB/s
[21:58] <llogan> better than mine
[21:59] <dakta> llogan: I'm sorry, but all of my music is lossless FLAC, so songs are all like 34 mb
[22:00] <llogan> dakta: i'll be here for another 2.75 hours.
[22:00] <dakta> 70%, so close!
[22:01] <dakta> llogan: Maybe read the bug report link I sent in the meantime?
[22:02] <dakta> and I can try to update ffmpeg...
[22:07] <dakta> llogan: http://me.hackthetruth.org/01_Nonpareil_Of_Favor.m4a
[22:10] <llogan> http://pastebin.com/Pr3hGCdY
[22:12] <dakta> llogan: Thanks, so recent versions of ffmpeg CAN read the metadata properly.
[22:12] <dakta> llogan: Now I just need to upgrade ffmpeg, right?
[22:14] <dakta> llogan: Nevermind that question, can you guide me through the upgrade process?
[22:19] <llogan> dakta: i have no experience compiling on/for PPC.
[22:19] <dakta> llogan: Oh goodie.
[22:20] <llogan> if you're not using ffmpeg for encoding, then a simple "./configure --enable-gpl" would be a good first step.
[22:20] <llogan> https://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuideHardy might be useful but possibly bloated
[22:21] <llogan> the PPC machines in fate.ffmpeg.org seem to be using --cc='ccache gcc-4.4' or such
[22:22] <llogan> i imagine compiling on the WD device would be glacially slow.
[22:22] <llogan> if possible.
[22:24] <dakta> compilation is glacially slow. it might be a 1 GHz at best.
[22:24] <llogan> i thought it would have been worse
[22:25] <tm512> Did a test, and it records the audio in with the matroska file, but it causes bad framerate dropping, saying that "Que input is backward in time"
[22:26] <tm512> the amount of frames it dropped got worse as the recording went on
[22:26] <dakta> i havent benchmarked it yet because installing a decent command line only benchmarking suite is a major pita, for somev reason.
[22:28] <tm512> would it be faster to record the audio and video seperately, then mkvmerge them?
[22:42] <siganderson> llogan, I think I solved my problem, I used ffmpeg two times, first time I directed the output to a pipe and then I used ffmpeg again to send to ffserver
[00:00] --- Wed Dec 12 2012