[Ffmpeg-devel-irc] ffmpeg.log.20140519

burek burek021 at gmail.com
Tue May 20 02:05:01 CEST 2014

[00:01] <c_14> You're using libav, not ffmpeg. Either see #libav for support or install/download ffmpeg.
[00:15] <waressearcher2> JEEB: sup
[00:19] <waressearcher2> blippyp: sup
[01:46] <GEEGEEGEE> Hi im trying to switch from VLC streaming x264 ts to ffmpeg streaming vp80 webm but I cant find any guides on where to start
[01:46] <GEEGEEGEE> i currently run VLC to transcode the stream, and also VLC on my servers
[01:53] <socksandsandals> how can I create an AVFrame in YUV420P format that's all black?
[01:53] <socksandsandals> should I set all the data bytes to 0?
[01:54] <llogan> GEEGEEGEE: http://trac.ffmpeg.org/wiki/vpxEncodingGuide
[01:55] <GEEGEEGEE> llogan, but what about the output? Can ffmpeg output onto a network port like VLC? or will i need to configure ffserver/icecast first?
[01:55] <GEEGEEGEE> also my input is from a HTTP link
[01:56] <llogan> see ffmpeg -protocols
[01:56] <llogan> and "man ffmpeg-protocols"
[01:56] <llogan> or http://ffmpeg.org/ffmpeg-protocols.html if using recent ffmpeg
[01:58] <GEEGEEGEE> ok thanks
[02:26] <derric> I am trying to compile ffmpeg with a number of external libraries, and even though I get the libraries sucessfully built, ffmpeg seems to lack the ability to find them at linking time.
[02:27] <c_14> can you paste the error and your configure command/output
[02:28] <derric> ./configure --prefix=$INSTALL_PATH  --enable-gpl --enable-version3 --enable-nonfree \
[02:28] <derric> 20:28 --extra-ldflags="-L$INSTALL_PATH/lib" \
[02:28] <derric> 20:28 --extra-cflags="-I$INSTALL_PATH/include" \
[02:28] <derric> 20:28 --enable-libmp3lame --enable-libtwolame --enable-libvpx --enable-libx264 --enable-avisynth \
[02:28] <derric> 20:28 --enable-libvpx --enable-libilbc --enable-libopus --enable-frei0r --enable-libxvid \
[02:28] <derric> 20:28 --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libwavpack --enable-libxavs \
[02:28] <derric> 20:28 --enable-x11grab  --enable-libtwolame --enable-fontconfig --enable-gnutls --enable-ladspa \
[02:28] <c_14> eh, please use a pastebin service so you don't spam the channel
[02:29] <derric> 20:28 --enable-libfreetype --enable-opengl --enable-libpulse --enable-libzvbi --enable-libaacplus \
[02:29] <derric> 20:28 --enable-libbs2b
[02:29] <derric> output is ERROR: libbs2b not found
[02:30] <derric> The output is similar when I try a number of other libs that I built and installed.
[02:31] <derric> OK.
[02:33] <c_14> Is libbs2b installed correctly in $INSTALL_PATH/{lib,include} ?
[02:34] <derric> http://paste.debian.net/100522/
[02:34] <iive> derric: there is config.log that holds the tests and the errors (if any). try to find the relevant (bs2b) test and put it in pastebin site.
[02:34] <derric> c_14:  I believe so.  I built and installed all the rest of the enabled items the same way and they get detected OK.
[02:35] <derric> They all appear to have the proper files in those directories.
[02:35] <iive> c_14: it would be good to always use the phrase "pastebin site" saves a lot of headache.
[02:35] <derric> Even the ones that fail to get detected.
[02:35] <c_14> iive: I think I'll do that from now on.
[02:36] <c_14> derric: Have you tried with --extra-libs="-ldl"
[02:37] <derric> About 25% of the libs I built fail to get detected by ffmpeg at compile time.  I could make a list of which one work and which ones fail.
[02:37] <derric> c_14:  What with just --extra-libs="-ldl" verbatim?
[02:38] <c_14> Adding that to your configure options
[02:38] <derric> OK.
[02:41] <GEEGEEGEE> How come libvpx looks so much worse than x264 at the same bitrate?
[02:45] <c_14> Some codecs look better at certain bitrates compared to other codecs, it also depends a lot on the source and your encoding options though. I tend to get relatively decent quality on the vpx encodes I use using the same or a slightly lower bitrate.
[02:45] <c_14> Are you just setting bitrate or bitrate and crf?
[02:46] <GEEGEEGEE> im using -maxrate
[02:46] <derric> c_14:  Adding that line gets rid of all the extra libs that do get detected. :|
[02:46] <c_14> GEEGEEGEE: That'll only set the maximum rate, the actual rate you're getting is probably much lower.
[02:46] <c_14> derric: So it breaks more stuff?
[02:46] <derric> Yep.
[02:46] <GEEGEEGEE> so I should use -minrate as well?
[02:48] <c_14> GEEGEEGEE: I'd go with -crf and -b:v like the wiki says: https://trac.ffmpeg.org/wiki/vpxEncodingGuide It's what I've been doing and it's treating me pretty well so far.
[02:48] <GEEGEEGEE> ok thanks
[02:48] <c_14> derric: did you set and export PKG_CONFIG_PATH ?
[02:50] <derric> c_14:  What should that point to?
[02:51] <c_14> In your case $INSTALL_PATH/lib/pkgconfig
[02:51] <derric> c_14:  I'll try that.
[02:56] <derric> c_14:  That seems to have done the trick for libbs2b.  Now let me see if the rest of the troublesome libs get detected now...
[03:14] <waressearcher2> yo
[03:14] <derric> c_14:  libopenjpeg is still refusing to get detected, although I think that is problem with its installtion script, which seems to be doing an incomplete job.  All of the other previously non-detected libs I have checked so far seem to detected now.  I think the PKG_CONFIG_PATH is what I was missing.  Ty.
[03:15] <c_14> glad it helped
[03:25] <GEEGEEGEE> When configuring ffserver why does it need to know the framerate, video size, and other settings? I dont want to transcode it on the server, just to distribute it to my clients
[03:25] <c_14> ffserver sends that information to the ffmpeg process that's pushing content
[03:25] <c_14> ffserver doesn't actually handle the encoding
[03:26] <GEEGEEGEE> oh good
[03:50] <GEEGEEGEE> hmm Im getting "av_interleaved_write_frame(): Connection reset by peer
[03:50] <GEEGEEGEE> " and then ffmpeg closes
[03:50] <GEEGEEGEE> ffserver shows the POST request though
[04:33] <waressearcher2> can I ask about sox here ?
[04:33] <sacarasc> Try their mailing list.
[04:35] <waressearcher2> no
[04:35] <waressearcher2> too long
[07:54] <aarobc> I'm using a crf of 19 and -preset slower, but some output files are actually larger than what was put in!
[07:55] <pzich> so they were poorer quality than 19
[07:57] <aarobc> pzich: so I thought that was the ammount of detail from the source. is that something that determines a constant bit rate then?
[07:57] <pzich> well it controls how closely it matches to the source, 1 is near lossless, but at quite the file size
[07:58] <aarobc> but as long as the source is a less efficient codec, why wouldn't it always be a smaller file size?
[07:59] <pzich> because it's matching that quality as closely as it can, it doesn't know what are artifacts and what's desired quality
[07:59] <aarobc> Indeed...
[08:00] <pzich> if it's not something you're batching I'd recommend generating a various qualities and picking the smallest one that you're still happy with the compression in
[08:01] <aarobc> Well, there are about 500 files, so it's set up to run in a script, but I want to make sure it's as good as possible because I don't want to have to run this again
[08:02] <pzich> then I'd probably go for somewhere between 10 and 20, if you have the space
[08:02] <pzich> here's an example with some 4K footage I worked on recently: http://i.imgur.com/1lJVcz0.jpg
[08:02] <pzich> it's also crunched quite a bit from imgur, but it gets the point across
[08:03] <aarobc> Indeed, that is a good example
[08:04] <pzich> with a 330 MB 4K ProRes 709 goes between 239 MB and 164 KB, depending on the quality
[08:04] <pzich> (we ended up going with something between 15 and 20)
[08:05] <aarobc> pzich: so if the source is shitty it will just balloon the output from setting it low?
[08:06] <pzich> every time you re-encode, if you're not encoding losslessly, you're lowering the quality
[08:06] <pzich> but sometimes the parts that are lost are unimportant, or worth it because of file size
[08:07] <pzich> if you want the obtain the best quality and file size without going through each video one by one, I'd recommend bucketing them by file type and resolution, and then dial in the quality for each of those buckets
[08:07] <pzich> or do that for just one video and run that for all of them
[08:10] <aarobc> yeah, that's kinda what I'm doing.
[08:11] <pzich> so CRF 19 is bigger than the input file sizes, I'd look over the quality and then try to go smaller, and if you're happy with that keep going until you're not, etc., etc.
[08:11] <pzich> or you can go the other direction since lower quality encodes are faster
[08:12] <aarobc> pzich: do you use multi-threaded encoding or does that hurt the quality too much?
[08:12] <pzich> I have 8 cores on this machine so I usually go with 8 threads, I haven't heard anything about that affecting the quality, but maybe someone else in here knows more about that.
[08:14] <aarobc> yeah, I have 6 cores on the server, but encoding is pretty slow, so I'm right now looking at setting something up to pull the file to my local machine, encode, and upload the output.
[08:14] <aarobc> google fiber is yummy
[08:15] <pzich> yeah if you're local machine is faster and the connection is good, that's not a bad way to go
[08:15] <pzich> err, your*
[08:16] <pzich> cbreak-work: Disney Research Zurich?
[08:16] <cbreak-work> hmm... yes? :)
[08:16] <pzich> I was just trying to figure out your hostname
[08:17] <cbreak-work> neat, isn't it? I picked it myself :)
[08:17] <cbreak-work> (We are encouraged to use disney chars as names of our computers)
[08:17] <cbreak-work> unfortunately, hal was already taken by a coworker...
[08:18] <pzich> aww, that's a good one
[08:18] <aarobc> Is GPU accellerated encoding a thing yet?
[08:20] <pzich> I'm pretty sure it is, otherwise I'm not sure why we just put in three new GPUs on this encoder box
[08:22] <aarobc> pzich: I haven't found any documenation for gpu accelerated encoding... does that only work on windows?
[08:25] <pzich> hmm, there's https://forums.adobe.com/message/5478209 and some devices had hardware GPU decoding, which ffmpeg might take advantage of (I don't know though)
[08:27] <aarobc> for shame. I'm running amd
[08:27] <pzich> This thing says they use AMD's OpenCL, but I don't know anything about it: http://www.mainconcept.com/products/sdks/gpu-acceleration/#c14667
[08:28] <aarobc> Yeah I'm looking at that right now, but I hope that doesn't mean I have to install their proprietary drivers.
[08:39] <aarobc> pzich: so you actually use ffmpeg for your video transcoding, and it's gpu accellerated? Are there any flags to set?
[08:44] <pzich> aarobc: I can't confirm if or how well ffmpeg is utilizing the GPU.
[08:49] <pzich> it sure looks to be using it while I'm encoding though
[08:51] <aarobc> Going to try it in windoze then
[09:00] <pzich> if someone sees aarobc tell him it doesn't look like the GPU really is getting used that much more, this is during and after encode: http://i.imgur.com/bCWAwrM.png
[09:24] <excalibr> Hi! Is there way to hide those enabled compile/build msg when you run ffmpeg?
[09:25] <excalibr> by msg i mean options
[09:28] <excalibr> Never mind got it. -hide_banner is what I want
[09:57] <decci_> Hi
[09:57] <decci_> I am getting this error
[09:58] <decci_> http://paste.ubuntu.com/7487380/
[09:59] <decci_> Any idea why its accessible through shell and not through web
[10:01] <spaam> check PATH
[10:02] <decci_> spaam:  echo $PATH /usr/local/jdk/bin:/usr/lib64/qt-3.3/bin:/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/root/bin
[10:02] <spaam> the web have the same thing  ?
[10:05] <decci_> spaam:
[10:05] <decci_> spaam: _SERVER["PATH"]	/bin:/usr/bin
[10:05] <spaam> and where did you install ffmpeg +
[10:05] <spaam> ?
[10:06] <spaam> in /usr/local/bin?
[10:06] <decci_> spaam: yes
[10:06] <spaam> there you have the problem
[10:06] <decci_> spaam: /usr/bin/ffmpeg FFmpeg version 0.6.5, Copyright (c) 2000-2010 the FFmpeg developers   built on Jan 29 2012 17:52:15 with gcc 4.4.5 20110214 (Red Hat 4.4.5-6)   configuration: --pre
[10:06] <decci_> spaam: Just few lines above pasted
[10:06] <spaam> you need to add /usr/local/bin to the PATH that PHP is using
[10:07] <spaam> what?
[10:07] <decci_> Where it says it using /usr/local/bin
[10:07] <spaam> you said /usr/local/bin  now /usr/bin ?
[10:07] <decci_> spaam: its /usr/bin/ffmpeg
[10:07] <decci_> spaam: Sorry if that confused you
[10:08] <spaam> have you tried start /usr/bin/ffmpeg from PHP instead of using whereis things ?
[10:08] <decci_> spaam: Looks like somethig to do with error: Cannot execute using backquotes in Safe Mode in /home/upeoapp2/public_html/ffmpegtest/test.php on line 4
[10:08] <spaam> there you have your problem
[10:08] <decci_> spaam: The first thing is no command is working
[10:09] <decci_> spaam: Looks like web host compan has everything in chroot
[10:09] <spaam> this is an issue for ##php and not #ffmpeg
[10:09] <decci_> spaam: But I was expecting atleast ls should have work
[10:09] <spaam> read the error message
[10:10] <spaam> talk to ##php on how to fix the issue.
[10:10] <decci_> spaam: I dint understand that error message...what it actually mean
[10:10] <decci_> spaam: #php Cannot join channel (+i) - you must be invited
[10:10] <decci_> spaam: My bad
[10:10] <spaam> ##php
[10:11] <spaam> it cant execute pwd  beacuse you are running php in safe mode.
[10:11] <spaam> talk to those php guys on how to fix it.
[10:12] <spaam> when you can start programs from php and still have issues with decoding / encoding videos with ffmpeg. feel free to come back and tell us about that issue.
[15:26] <waressearcher2> is it possible to mix 10 mp3 files ? I use "sox -m 1.mp3 2.mp3    10.mp3 out.mp3", but is it possuble with ffmpeg ?
[15:27] <c_14> What do you mean with mix?
[15:28] <waressearcher2> c_14: to mix them I have different music in each of them and I want one mp3 to contain all of them
[15:28] <c_14> Du you want to concatenate the files or do you want to have one file with multiple audio streams?
[15:29] <c_14> s/Du/Do
[15:29] <waressearcher2> one stream
[15:29] <c_14> https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[15:29] <c_14> It'll work with music files as well.
[15:29] <waressearcher2> they are all 15 minutes audio, I want one 15 audio with all audio from all of them
[15:30] <c_14> If they're all the same codec you can use the concat demuxer, if they're different you'd have to use the filter.
[15:31] <waressearcher2> they are all 320Kbit mp3 files 44100Hz
[15:32] <c_14> Then you can probably just use the concat demuxer.
[15:32] <waressearcher2> c_14: dude
[15:33] <waressearcher2> c_14: concat is when begining of the second file starts after first file ends right ? I don't want to out.mp3 be 150 minutes long, I want it to be 15 minutes, as all 10 files are
[15:33] <waressearcher2> I want "to mix"
[15:34] <c_14> Look at the amix filter.
[15:34] <c_14> That should do what you want.
[15:34] <waressearcher2> I know how to concatenate, I want to "mix" or "merge" or whatever you call it
[15:34] <c_14> https://ffmpeg.org/ffmpeg-filters.html#amix
[15:36] <waressearcher2> dawgthanks
[15:37] <waressearcher2> after 10 minutes of explanation I got the info
[15:37] <waressearcher2> how much simpler world was before computers
[15:45] <waressearcher2> I have many ace files, but I need to use "-i" in front of each one like: "-i 2_2.ac3 -i 2_3_2.ac3 -i 2_5_2.ac3", can it be done in a easier way, like "-i *_2.ac3" ?
[15:46] <waressearcher2> s/ace/ac3/
[15:47] <mrskman> https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[15:49] <waressearcher2> mrskman: where did you get that link ?
[15:49] <waressearcher2> it does smell a bit
[15:50] <waressearcher2> or do you suggesting to use "-i list_all.txt" where list of all files is in list_all.txt ?
[15:50] <klaxa> waressearcher2: afaik there is no easier way unless you use something like ffmpeg $(for i in *_2.ac3; do echo -n "-i $i") <something> out.ac3
[15:50] <klaxa> hmm or something like that
[17:29] <DelphiWorld> hi guys
[17:29] <DelphiWorld> do ffmpeg exist in debian sid? its not installing...
[17:30] <azk> Doesn't look like it
[17:30] <c_14> the debian repos use libav by default
[17:30] <DelphiWorld> no, i think i need the contrib one?
[17:30] <c_14> If you want to use ffmpeg, you'll have to compile from source or use the static builds.
[17:30] <c_14> Hmm?
[17:31] <DelphiWorld> deb http://ftp.uk.debian.org/debian/ sid contrib-nonfree
[17:31] <DelphiWorld> i think
[17:31] <DelphiWorld> but its bad url
[17:35] <c_14> I'm pretty sure debian doesn't have ffmpeg in its repos. ffmpeg is in debianmultimedia though if you want to try that.
[17:36] <DelphiWorld> c_14: repo url please
[17:44] <c_14> http://www.deb-multimedia.org/
[17:45] <c_14> The list of repos is at the waaay bottom
[22:20] <jpsharp> I'm getting the dreaded Alsa buffer XRUN when trying to encode audio/video from a capture card using X264/AAC into an FLV container streaming to ngninx.  But only when using X264.
[22:21] <jpsharp> Sorenson works but it thrashes the hell out of the CPU.  Mpeg4 seems to encode nothing but a black screen for video.
[22:24] <pzich> I know nothing about this particular issue, but according to the ticket you can try increasing ALSA_BUFFER_SIZE_MAX http://trac.ffmpeg.org/ticket/615#comment:14
[22:28] <jpsharp> I'm not really in the mood to recompile alsa on a dozen boxes.
[22:34] <pzich> well, it sounds like your options are to reduce the quality or size so that the buffer size is ample, or increase the buffer size
[00:00] --- Tue May 20 2014

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