[Ffmpeg-devel-irc] ffmpeg.log.20130905

burek burek021 at gmail.com
Fri Sep 6 02:05:01 CEST 2013


[00:07] <chrisjunkie> Mavrik: Took your advice and looked at the ffmpeg.c source
[00:08] <chrisjunkie> Mavrik: this line here http://www.ffmpeg.org/doxygen/trunk/ffmpeg_8c-source.html#l01388
[00:08] <chrisjunkie> Anyway, I have it working using the reference DTS of the AVStream
[00:08] <chrisjunkie> Seems to be working anyway
[00:43] <seu_barriga> hello
[00:44] <seu_barriga> I'm trying to set the output bitrate using the -b:v option, but I don't know why it's being ignored
[00:45] <seu_barriga> the conversion command is avconv -re -i video.mp4 -vcodec copy -b 100k -bufsize 200k -f flv rtmp://my-rtmp-output
[00:45] <seu_barriga> shouldn't it be enough?
[00:46] <llogan> seu_barriga: ^
[00:47] <llogan> avconv is not from FFmpeg. so either use real ffmpeg or go to #libav
[00:48] <seu_barriga> oh, I thought they were the same
[00:48] <seu_barriga> ok, thx llogan
[00:54] <chrisjunkie> Mavrik: OK so not quite working, all the timestamp stuff is correct, but now I'm not getting any key frames decoded in the MKV container
[00:54] <chrisjunkie> but if I use ffmpeg to convert to .mp4, works fine
[00:55] <chrisjunkie> [h264 @ 0x1343aa0] Missing reference picture, default is 0
[00:55] <chrisjunkie> [h264 @ 0x1343aa0] decode_slice_header error
[00:55] <chrisjunkie> [h264 @ 0x1343aa0] Reinit context to 640x368, pix_fmt: 1210 bitrate=1387.0kbits/s dup=37 drop=0
[00:57] <chrisjunkie> More than likely because i'm not waiting for a keyframe
[01:05] <chrisjunkie> Fixed it :-)
[01:06] <zygew> which app does linux use to download stream media,like WMR,Hidownload?
[02:34] <Chat2216> Hii
[06:08] <PovAddict> how can I join ISM (IIS smooth streaming) fragments into a single .mp4?
[07:04] <PovAddict> looks like the fragments are just moof+mdat
[07:04] <PovAddict> I can't find anything that can play them, everything I tried demands a moov atom
[09:11] <ayad_> hello
[09:12] <ayad_> i installed the ffmpeg-1.2, i need to find a command line to get the video with mjpeg and read or optimize with flv/swf
[09:12] <ayad_> thank's to help me
[10:04] <ayad_> someone can to help me ?
[10:06] <relaxed> ayad_: why do you need mjpeg?
[10:08] <ayad_> yes i need to get the movie by mjpeg
[10:08] <ayad_> i search a command line to get the video mjpeg to flv/swf
[10:09] <relaxed> so your input is a mjpeg video and you want the output to be flv?
[10:09] <ayad_> yes input mjpeg video and output flv
[10:10] <relaxed> ffmpeg -i mjpegvideo.avi -c:v libx264 output.flv
[10:15] <ayad_> i get the input video by the network camera, how i must do
[10:15] <ayad_> ffmpeg -i http://ip_address/image -&1
[10:17] <dawe07> Hello, is here somebody who can help me with video conversion. From flv to mp4
[10:18] <Mavrik> depends
[10:18] <Mavrik> did you read any documentation or google posts?
[10:19] <relaxed> ayad_: http://trac.ffmpeg.org/wiki/How%20to%20capture%20a%20webcam%20input
[10:19] <relaxed> oh, nevermind, just use the url as your input.
[10:20] <ayad_> relaxed_ i check up directly
[10:22] <ayad_> relaxed_ to get the video in my network cam, the url is http://ip_address/image or mjpeg,
[10:22] <ayad_> so in command line, i must ffmpeg -i http://ip_address/.... to flv
[10:23] <dawe07> Marvik: I read a lot, I have problem only with audio/video synchronisation
[10:24] <dawe07> Is possible to synchronise without using "itsoffset" or something like this
[10:24] <dawe07> because flv is not out of sync, but mp4 after convertion is
[10:29] <Mavrik> dawe07, hmm, that certanly shouldnt happen
[10:30] <Mavrik> dawe07, can you throw your command line and output on pastebin?
[10:31] <dawe07> Mavrik: ok moment
[10:34] <dawe07> Marvik: http://pastebin.com/xZhYA4Qc
[10:40] <ayad_> relaced _?
[10:42] <Mavrik> dawe07, hmm, that looks like a speex decoder issue
[10:43] <Mavrik> dawe07, also libvo_aacenc is pretty crap
[10:43] <Mavrik> try resampling audio to 22050 to see if the issues persist
[10:43] <ayad_> dawe07_ if my input video is mjpeg , i need to transcode to flv .swf
[10:43] <dawe07> second codec what can I use is nellymoser, but that is older
[10:43] <ayad_> can you hepl my ffmpeg version 1.2
[10:45] <Mavrik> dawe07, mhm, it could be just that libvo is problematic with "non-standard" sampling rate
[10:47] <dawe07> I added this to resample: -ar 22050  and not solved
[10:48] <dawe07> if I add itsoffset 0.7 to audio, then it is correct. But I will use ffmpeg for many videos with variable lengths
[10:51] <dawe07> and when I change output file not mp4 but flv, then audio is synced without problem. So the issue is when changing container
[10:51] <Mavrik> dawe07, is it only container that changes?
[10:52] <Mavrik> in the output?
[10:52] <Mavrik> or also codecs with it?
[10:53] <dawe07> Marvik I think with change codec. http://pastebin.com/8xCxKhEz
[11:10] <Mavrik> dawe07, that's wierd. If you have newest ffmpeg then you should submit a bug report on TRAC with a sample of your file
[11:10] <Mavrik> so that can get fixed
[11:11] <dawe07> Marvik I have FFmpeg 64-bit Static Versions from http://ffmpeg.zeranoe.com/builds/
[11:12] <dawe07> When I googled this problem I founded that somebody else had this problem
[11:12] <dawe07> but their solution not worked for me
[11:13] <dawe07> they suggested to record two separated files audio and video and then connect it with ffmpeg, but this was same for me
[11:20] <dawe07> and thank you for your assistance Mavrik
[11:21] <Mavrik> dawe07, mhm, but as I said, that's almost certanly a bug in ffmpeg
[11:22] <Mavrik> if flv works and mp4 doesn't then it needs to be fixed
[11:22] <dawe07> so i will try to add it to bug report
[11:23] <dawe07> when I convert video Im trying it in BSPlayer
[11:24] <dawe07> one more question
[11:25] <dawe07> u said that libvo_aacenc is crap, Can u suggest me better one?
[11:30] <moonmayor> hey, I'm following this example that creates a mosaic of scenes, but I want to output each scene snapshot as an individual image. any ideas?
[11:30] <moonmayor> ffmpeg -i video.avi -vf select='gt(scene\,0.4)',scale=160:120,tile -frames:v 1 preview.png
[11:37] <Mavrik> dawe07, libfdk_aac is pretty much the best available for ffmpeg
[11:37] <Mavrik> internal aac encoder otherwise, it's about on-par with libfaac and vo_aacenc with slightly more features and less licensing problems
[11:39] <dawe07> so can I use it for many videos recorded from webcam and published on websites?
[11:40] <dawe07> but Im not sure how to add this codec "Unknown encoder 'libfdk_aac'"
[11:41] <Mavrik> ffmpeg has to be compiled with support for that library.
[11:43] <Kurvivor> can one use ffmpeg to cut the video in parts? I mean, get video and cut off entire left part of it
[11:43] <Kurvivor> or right
[11:43] <Mavrik> Kurvivor, yep, crop filter
[11:43] <Mavrik> you'll have to reencode the video of course
[11:44] <Kurvivor> aha
[11:44] <Kurvivor> could you give me example command line?
[11:45] <Mavrik> it's in the filter docs on the webpage
[11:45] <Mavrik> several examples.
[11:46] <Kurvivor> i see the page
[11:46] <Kurvivor> it is embarassing to ask, but how is filter supplied in command line?
[11:48] <Mavrik> Kurvivor, -vf :)
[11:49] <Mavrik> ffmpeg -i <your encoding parameters> -vf crop=....
[11:49] <Mavrik> you can chain them with a comma if you want to use scale or something else as well
[11:49] <Mavrik> if you need a basic H.264 tutorial it's here: https://www.virag.si/2012/01/web-video-encoding-tutorial-with-ffmpeg-0-9/
[11:51] <Kurvivor> and one more question
[11:51] <Kurvivor> do filters go before or after codec?
[11:51] <Mavrik> usually is wise to put -vf after -codec:v :)
[11:53] <Kurvivor> thank you kindly
[12:50] <_d0t> hi. How do I output multiple frames per one encode_frame() run? This is needed in case of b-frames.
[12:58] <braincracker> h
[14:56] <mittens> hey is there an easy way to convert an mkv file with ac3 audio to mpeg4? currently i have to use mencoder and avidemux and ffmpeg
[14:57] <JEEB> `ffmpeg -i welp.mkv -c:v mpeg4 (or libxvid, latter probably simpler to set up) -c:a copy (if you want to just copy the AC3 track) out.file`
[14:57] <JEEB> should do that just fine
[14:58] <sacarasc> In most matroska video files I've come across there has been MPEG4 video already.
[14:59] <JEEB> I am guessing he means MPEG-4 Part 2
[14:59] <JEEB> not MPEG-4 Part 10
[14:59] <JEEB> but not that I know, I was just guessing \o/
[15:01] <mittens> the video is fine its the ac3 i have problems with, my tv doesnt support iy
[15:01] <mittens> it*
[15:02] <JEEB> oh
[15:02] <JEEB> welcome to how broad the wording "MPEG-4" is :P
[15:02] <JEEB> anyways, I will guess you want aac
[15:03] <mittens> my usual way of converting never works, i have to use avidemux to pull the audio and then convert that, then convert the video and put them back together
[15:03] <JEEB> `ffmpeg -i welp.mkv -c:v copy (copy the video) -c:a aac (or fdk-aac if you want to build it yourself, much better quality, but unfortunately not redistributable) -b:a 192k (192k for 2ch) -strict experimental (enables the 'aac' encoder) out.mkv`
[15:04] <JEEB> that should work
[15:05] <mittens> thanks i'll give it a try
[16:37] <PovAddict> how can I join ISM (IIS smooth streaming) fragments into a single .mp4?
[16:37] <PovAddict> looks like the fragments are just moof+mdat
[16:37] <PovAddict> I can't find anything that can play them, everything I tried demands a moov atom
[17:09] <Mavrik> PovAddict, there has to be an index somewhere
[17:11] <PovAddict> index?
[17:11] <Mavrik> moov atom contains an index for a mp4 file
[17:12] <Mavrik> that's why you need it to play& and the IIS somehow needs to have an index of contents of those mp4 files to fake proper MOOV on stream
[17:12] <PovAddict> there is an XML manifest
[17:15] <PovAddict> <StreamIndex Type="video" Name="video" Chunks="65" QualityLevels="8" MaxWidth="1280" MaxHeight="720" DisplayWidth="1280" DisplayHeight="720" Url="QualityLevels({bitrate})/Fragments(video={start time})">
[17:15] <PovAddict> <QualityLevel Index="0" Bitrate="2962000" FourCC="WVC1" MaxWidth="1280" MaxHeight="720" CodecPrivateData="250000010FD37E27F1678A27F859F180490825A645A6440000010E5A67F840" />
[17:24] <_d0t> B/qui
[17:24] <_d0t> oops.. sorry
[17:41] <PovAddict> Mavrik: but I have no idea how I'd go about crafting my own moov header out of that
[18:02] <Chat2764> Ok
[18:55] <MarcWeber> Does anybody know which hardware accelerated h264 encoding solutions exist for linux?
[19:04] <JEEB> MarcWeber, the only one even vaguely usable is the intel's one, and for that you would want as new as possible CPU (haswell etc.), everything else is mostly garbage. Not sure about nvidia's ASIC-based encoder, either, but GPUs tend to eat a lot of power compared to an intel CPU in general.
[19:16] <ffmpeg-noob> hello, guys ... have a few questions from very beginner about ffmpeg ... anyone is alive here to be so kind to help?
[19:17] <JEEB> just ask and then someone might reply
[19:17] <JEEB> that's how it goes
[19:18] <ffmpeg-noob> imagine I want to create "helloWorld" app with ffmpeg support in MSVC++ ... for example simple colsole app .. .what ffmpeg files do I need for this?
[19:24] <ffmpeg-noob> will ask in other way ... do I need to compile ffmpeg for this or there is something ready?
[19:38] <ffmpeg-noob> I thought this is help channel)
[19:43] <PovAddict> ffmpeg-noob: it is
[19:43] <PovAddict> ffmpeg-noob: it's also an IRC channel, which means you need patience
[19:46] <ffmpeg-noob> PovAddict: in average how much time it is needed?
[20:15] <PovAddict> ffmpeg-noob: maybe infinite if nobody knows the answer?
[20:16] <braincracker> ;>
[20:16] <braincracker> h
[20:16] <klaxa> the question is rather vague too
[20:16] <MarcWeber> ffmpeg-noob: Goto ffmpeg homepage and have a look at the downloads section?
[20:16] <klaxa> if you want to use ffmpeg in your software, you need at least the headers and the libraries
[20:16] <klaxa> and it's not actually ffmpeg but libav*
[20:16] <braincracker> PovAddict<= depends on the payment rate
[20:16] <klaxa> (also not avconv)
[20:16] <braincracker> ;)
[20:17] <braincracker> msvc ? forget me then
[20:17] <braincracker> gcc
[20:20] <ffmpeg-noob> klaxa so should I compile it by myself?
[20:23] <klaxa> ffmpeg-noob, i don't know, if you are on linux you can just install the libraries and headers from your distro
[20:23] <klaxa> on windows, no clue
[20:23] <klaxa> dunno about mac os x either
[20:23] <braincracker> ffmpeg-noob<= why not use linux ?
[20:31] <ffmpeg-noob> braincracker: I use Windows and going to try to develop something on it ... so Linux is on the work only)
[20:31] <braincracker> try work on linux
[20:31] <braincracker> and develop on gcc
[20:31] <braincracker> it will be worth it long-term.
[20:31] <ffmpeg-noob> currently I need exactly Windows info
[20:32] <braincracker> ok exactly
[20:33] <braincracker> good thing i'm not using win* for anything since 2008
[20:33] <ffmpeg-noob> why? )
[20:33] <braincracker> because i use linux, and do not play cs on win*
[20:34] <braincracker> for work, linux is the way, for win* games, you may decide win*
[20:34] <braincracker> actually, linux is better for anything else than playing win* games.
[20:35] <ffmpeg-noob> well, everyone chooses by himself))
[20:35] <braincracker> for those wo do not play...
[20:35] <braincracker> h
[20:35] <ffmpeg-noob> you don't play anything?
[20:35] <braincracker> i don't have time now ;/
[20:35] <braincracker> but was playing openttd on linux last year
[20:36] <braincracker> and gta and redalert on dosboy for example
[20:36] <braincracker> dosbox
[20:37] <ffmpeg-noob> probablyit's even reasonable to not spend time on games ...
[20:37] <braincracker> i find it less entertaining to even play a simulator, just go with the real thing anyway...
[20:38] <braincracker> fly, ride, drive
[20:40] <ffmpeg-noob> funny) as for me I was all the summer traveling) and now have to look into ffmeg ... which is so dark )
[20:40] <ffmpeg-noob> ffmpeg
[00:00] --- Fri Sep  6 2013


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