[Ffmpeg-devel-irc] ffmpeg.log.20140417

burek burek021 at gmail.com
Fri Apr 18 02:05:01 CEST 2014


[01:33] <shevy> ffmpeg -i foo.mp3 ack.mp4
[01:34] <shevy> error result:
[01:34] <shevy> "[aac @ 0x870bfc0] The encoder 'aac' is experimental but experimental codecs are not enabled, add '-strict -2' if you want to use it."
[01:34] <shevy> oops
[01:34] <shevy> oh well, I can't get the commandline right?
[01:34] <shevy>   ffmpeg -strict -2 -i foo.mp3 ack.mp4
[01:34] <shevy> does not work
[02:23] <wiak> just a stupid question, how can i use ffmpeg to convert 4k tiffs into lossless that does not use twice the size of the orginal tiff etc?
[02:23] <wiak> i know of huffyou and lagarith, but i dont think they are made for 4k yet
[04:28] <sor_> i compiled ffmpeg version 2.1.3 with   libavcodec and every program i try to compile failes at ffmpeg libav ? any thoughts
[04:30] <sacarasc> What does the config.log say? Where did you install ffmpeg to?
[04:32] <sor_> ./configure --prefix=/usr    everything looks great and ffmpeg itself wors great just the prgrams i compile against it fail
[04:33] <sacarasc> And the other programs' config.logs?
[04:34] <sor_> oder_la-ffmpeg.o
[04:34] <sor_> ffmpeg.c:45:2: error: unknown type name ‘AVFormatParameters’
[04:34] <sor_>   AVFormatParameters ap;
[04:34] <sor_> etc
[15:14] <jonascj> Hi all. I want to confirm my understanding of this. For streaming I would run ffserver which can serve streams (to media players, webbrowsers etc.) on one machine and on another machine I would run ffmpeg which feeds ffserver with content? Even though I only had one machine I would still need both ffmpeg and ffserver, right?
[15:16] <jonascj> Or rather the other way round. I am following a guide on how to stream a webcam from a raspberry pi. It install ffserver and ffmpeg on the raspberry pi. But I could potentially locate the ffserver on another machine and just feed that ffserver using ffmpeg on the raspberry pi?
[15:24] <c_14> Theoretically, yes.
[15:38] <Mavrik> jonascj, yes
[15:39] <Mavrik> jonascj, however remember that the actual encoding is done by the ffmpeg process, so you'll need transcoding horsepower on the device that runs ffmpeg
[15:51] <Zeranoe> is --target-os=win32 just for msvc, or should that also be used for mingw builds targeting windows
[17:07] <Fohlen> are there by any chance commands which might speed up this proccess? avconv -i 1.mp4 -c:v mpeg2video -q:v 2 -c:a libmp3lame output.mpg
[17:08] <Fohlen> I'm asking here because avconv adapts ffmpeg, and apparently the avconv channel is pretty empty
[17:08] <Fohlen> for a 300mb video it takes me up to 3 hours
[17:10] <Fohlen> is this normal behavoir dedicated to the codecs?
[17:12] <sacarasc> Fohlen: The avconv/libav channel is at #libav.
[17:13] <Fohlen> sacarasc: thank you.
[17:13] <sacarasc> Oh, didn't see what else you said. :D
[17:13] <Fohlen> :)
[17:13] <sacarasc> How many cores/cpus/whatever is the encoding using?
[17:14] <Fohlen> 2 cores, 2 virtual ones
[17:14] <sacarasc> It's using them all?
[17:15] <sacarasc> It could be that the input is requiring a lot to decode, so the encoding is slow.
[17:15] <Fohlen> sacarasc: it's using about 80% of the available cpu power
[17:15] <Fohlen> so pretty much, all except system and some additional
[17:15] <Fohlen> :D
[17:16] <sacarasc> There are ways to speed it up, but it will degrade the video quality going in...
[17:18] <Fohlen> sacarasc: will the degrade be notably?
[17:18] <sacarasc> I've never done it, maybe...
[17:21] <Fohlen> hmm.
[17:26] <ubitux> Fohlen: avconv adapts ffmpeg? huh?
[17:26] <Fohlen> ubitux: I though it was a fork, wasn't it?
[17:26] <ubitux> yes indeed
[17:26] <ubitux> i was wondering what you meant by that
[17:27] <Fohlen> :)
[17:36] <KirillB> plz help
[17:36] <KirillB> I have two video sources (one is webcam and another is video captured from the screen) and I want to stream it into one RTMP stream using ffmpeg.
[17:36] <KirillB>  It's possible to do so?
[18:00] <Memphiz> anybody from team ffmpeg around? this is about our (xbmc) shared booth at linuxtag 2014 in berlin this year
[18:00] <JEEBsv> you might want #ffmpeg-devel
[18:01] <Memphiz> thx
[18:21] <shevy> the option -y means to always overwrite and never ask back the user ever, when target file already exists, correct?
[19:00] <wbk> hi guys
[19:01] <wbk> i have a problem with ffmpeg
[19:01] <wbk> [svcd @ 02fc5aa0] buffer underflow st=0 bufi=43896 size=45471
[19:01] <wbk> [svcd @ 02fc5aa0] buffer underflow st=0 bufi=0 size=43925
[19:01] <wbk> [svcd @ 02fc5aa0] packet too large, ignoring buffer limits to mux it
[19:01] <wbk> [svcd @ 02fc5aa0] buffer underflow st=0 bufi=0 size=43925
[19:01] <wbk> Last message repeated 134328 times
[19:01] <wbk> and goes on....
[19:02] <wbk> that's a bug?
[19:02] <wbk> the command i used is: "ffmpeg -i merged.vob -ss 0:00:24.000 -to 0:52:16.320 -c copy output.vob"
[19:10] <uvx3> Hi. What is "pcm_..._planar" codec? What is the difference to not planar?
[19:29] <uvx3> What is "pcm_..._planar" codec? What is the difference to not planar?
[19:49] <watsonkp> Perhaps https://www.ffmpeg.org/doxygen/trunk/samplefmt_8h.html#af9a51ca15301871723577c730b5865c5 will help you
[19:51] <uvx3> watsonkp, Thanks, I'll read this :)
[20:11] <GunArm> I don't know if this is the right place to ask this, i'm just looking for a place with many people with above average knowledge of video codecs...
[20:12] <GunArm> i have a bunch of video files from when I recorded my old family movies off of VHS tapes.  They are uncompressed avi files so they are humongous
[20:12] <GunArm> does anyone have any advice about a good modern codec that will maximally preserve quality (within reason for a VHS rip) and not be so huge?
[20:13] <GunArm> maybe "codec" is the wrong word, format maybe
[20:16] <JEEB> use (lib)x264 and encode them to H.264 with it
[20:17] <JEEB> that's currently the most supported format, as well as the x264 implementation for it is both mature and very well performing
[20:17] <uvx3> Good codec is h264. It's superior to mpeg4 which is also good enough.
[20:17] <JEEB> H.264 is not a codec, it's a video format
[20:17] <JEEB> codec is an implementation that does both encoding and decoding
[20:18] <JEEB> use the CRF rate control mode to encode to a more or less specific "quality level"
[20:18] <JEEB> highest CRF value that still looks good to you is basically as much compression as you can take. A good value to start with as well as the default rate control value in x264 is CRF 23
[20:18] <JEEB> if it looks good, push it higher. if it looks bad, push it lower.
[20:19] <wbk> hi JEEB, can you help me with my problem please?
[20:19] <JEEB> rince and repeat until you have found the highest that still looks good
[20:19] <JEEB> wbk, you seem to be muxing with the SVCD muxer while the data is going over its limits
[20:20] <JEEB> it is still getting muxed, it just ignores the VBV values
[20:20] <wbk> JEEB, let me explain to you what i need to do
[20:20] <JEEB> I don't care and I don't know about that muxer
[20:20] <wbk> i have a vob file, and i need to cut some parts in the end and at the begin
[20:21] <wbk> what i'm using is the right command with the right parameter?
[20:31] <uvx3> watsonkp, ok, I've got it, the planar format. Thank you.
[20:45] <shevy> can I demultiplex with ffmpeg? like if I have a .mpg file, I want to obtain audio + video stream separately
[20:50] <c_14> You can try something like: ffmpeg -i source -map 0:a -c:a copy audioout -map 0:v -c:v copy videoout
[20:53] <uvx3> c_14, cool :) I use -an to extract video and any audio-only file format (e.g. .wav) to extract audio.
[21:20] <shevy> hmm
[21:20] <shevy> that would be the command for demultiplexing?
[21:20] <shevy> gonna try
[21:59] <troulouliou_dev> hi does abybody have a working imlplementation of the crc algo used in dts-hd ma extension substream ??
[21:59] <troulouliou_dev> it is crc16 ccitt false i think but i m stuck at validating it
[22:33] <Sam__> Netflix contents are are encrypted to just Manifest is encrypted not the header and payload
[22:33] <Sam__> Netflix contents are are encrypted or just Manifest is encrypted not the header and payload
[23:11] <Sam__> etflix contents are are encrypted or just Manifest is encrypted not the header and payload
[23:11] <Sam__> Netflix contents are are encrypted or just Manifest is encrypted not the header and payload
[00:00] --- Fri Apr 18 2014


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