[Ffmpeg-devel-irc] ffmpeg.log.20160730

burek burek021 at gmail.com
Sun Jul 31 03:05:01 EEST 2016


[00:36:06 CEST] <wallbroken> hi folks
[00:36:26 CEST] <wallbroken> do you think is better to encode/decode with the last version of ffmpeg?
[00:36:35 CEST] <wallbroken> if yes, why?
[00:37:23 CEST] <klaxa> yes, possibly contains more performance tweaks and supports more codecs/specifics
[00:37:50 CEST] <c_14> Also bugfixes
[00:38:09 CEST] <wallbroken> just because windows xp supports ffmpeg since 2015
[00:38:17 CEST] <wallbroken> so, i need to move on a newer windows to doit
[00:38:36 CEST] <wallbroken> i can do it, but if there are no differences, i can stay on 2015 version
[00:39:34 CEST] <furq> ffmpeg should still run fine on xp, it's just the zeranoe builds which don't
[00:40:23 CEST] <furq> https://ffmpeg.zeranoe.com/forum/viewtopic.php?t=2937
[00:40:29 CEST] <furq> there are some recent xp-compatible builds listed in there
[00:40:35 CEST] <furq> or you could build it yourself
[00:41:29 CEST] <wallbroken> but zaranoie is the official on windows
[00:41:42 CEST] <wallbroken> and i don't want to build it myself
[00:41:43 CEST] <furq> they're no more official than any other builds
[00:42:37 CEST] <furq> and if you're concerned about security then you shouldn't really be using xp
[00:42:54 CEST] <wallbroken> as i said, i can do it on win 10
[00:53:59 CEST] <cvax> how do i convert any audio file to mp3 in any suggested bitrate?
[00:54:39 CEST] <furq> -i src -c:a libmp3lame -q:a 0 desc.mp3
[00:57:18 CEST] <cvax> thank you, sir
[02:37:25 CEST] <wallbroken> 32bit version and 64 will produce the same output?
[02:51:20 CEST] <codespells> I need to capture some noisy VHS video. Is there a filter in ffmpeg that can be used?
[02:52:23 CEST] <furq> codespells: https://ffmpeg.org/ffmpeg-filters.html#hqdn3d-1
[02:52:24 CEST] <codespells> Was looking at https://trac.ffmpeg.org/wiki/FilteringGuide but there is not really much info there
[02:52:28 CEST] <furq> other denoisers are available
[02:52:43 CEST] <codespells> other?
[02:53:31 CEST] <codespells> you mean like NLMeans etc
[02:53:32 CEST] <furq> atadenoise, dctdnoiz, owdenoise, removegrain
[02:53:39 CEST] <furq> nlmeans isn't in ffmpeg yet
[02:53:51 CEST] <furq> you'd have to use avisynth/vapoursynth or something
[02:54:22 CEST] <codespells> what would be normally used for an old VSH tape?
[02:54:32 CEST] <codespells> VHS
[02:55:18 CEST] <furq> i can't say i've ever tried
[02:55:23 CEST] <furq> hqdn3d seems to be quite widely used
[02:57:21 CEST] <codespells> I'll try it out. Does not seem to be any examples on that page.
[02:58:05 CEST] <furq> -vf hqdn3d=3:2:2:3
[02:58:18 CEST] <furq> that's what the medium preset in handbrake uses
[02:58:55 CEST] <furq> or just -vf hqdn3d
[03:00:23 CEST] <codespells> Thank you.
[03:07:35 CEST] <ljr1981> is there anything for doing audio-speech-to-text-to-SRT-CC?
[03:07:43 CEST] <ljr1981> (automatic)
[03:45:48 CEST] <kepstin> ljr1981: only thing I know of is YouTube, and it's, well, pretty bad. I can't think anything better exists.
[03:46:07 CEST] <kepstin> You're probably better off just paying a human to do it
[03:47:16 CEST] <codespells> uhh, was asked to write a denoising algorithm using wavelet transform using non-linear estimators using Bayesian theory for video. Anybody know of any GPL code out there that works along these lines?
[03:48:00 CEST] <codespells> Don't really care how hard it taxes the hardware...
[03:53:26 CEST] <codespells> Blah, its 4am here in Sweden. Gonna get a few hours of sleep.
[04:41:17 CEST] <jpleau> What do I need to include to have an implementation of AVDictionary? libavutil/dict.h has 'typedef struct AVDictionary AVDictionary', but I'm getting an incomplete type error because that's not a definition..
[04:45:52 CEST] <kepstin> jpleau: you don't use it except as a pointer passed to various functions. It's an opaque object.
[04:46:42 CEST] <kepstin> that header gives some examples of using it...
[04:48:37 CEST] <jpleau> I see. I was looking at the doc for AVFormatContext, is contains a AVDictionary* metadata. I thought it was just usable as a normal "" array "", guess not
[04:48:44 CEST] <jpleau> I'll look at that header, thanks kepstin
[04:49:13 CEST] <jpleau> (defining that struct in my own file works, but this is completely the wrong way of doing it :( )_
[09:34:56 CEST] <fling> How to specify which audio stream is for which video angle?
[10:49:19 CEST] <ZSU-23-4> which one device I should specify to capture sound?
[14:30:42 CEST] <Penthus> Hey guys I am having an issue when I use 2-pass with libx264. It will go fine up to a random point and then just get stuck and not progress. It wont give an error or anything. Changing from libx264 to mpeg4 for the same file will work fine. Am I missing something?
[16:42:24 CEST] <AnonBaiter> I have an issue with the .MPC file
[16:42:24 CEST] <AnonBaiter> when I encode a .mpc file to any codec, the resulting file flickers for no reason
[16:42:24 CEST] <AnonBaiter> I'm uploading the sample at... 20+ minutes or less
[16:42:24 CEST] <AnonBaiter> https://www.sendspace.com/file/p1hcft
[16:42:24 CEST] <AnonBaiter> here's the sample
[16:43:23 CEST] <durandal_1707> What's mpc?
[16:43:40 CEST] <AnonBaiter> it's an EA video format
[16:43:44 CEST] <AnonBaiter> check it out for yourself
[16:44:18 CEST] <durandal_1707> its pal8?
[16:44:30 CEST] <AnonBaiter> looks like NTSC to me
[16:48:27 CEST] <durandal_1707> and decoded one doesnt flicker?
[16:51:46 CEST] <AnonBaiter> the decoded one flickered to me
[16:52:35 CEST] <AnonBaiter> it goes like this:
[16:52:36 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] ignoring SEQ_START_CODE after 101
[16:52:36 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] ignoring seq ext after 101
[16:52:36 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] Invalid mb type in B-frame at 33 0
[16:52:36 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] Warning MVs not available
[16:52:36 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] concealing 400 DC, 400 AC, 400 MV errors in B frame
[16:52:37 CEST] <AnonBaiter> [mpeg2video @ 056ddf60] ignoring SEQ_START_CODE after 101
[18:01:30 CEST] <wrs> hey, im wondering if its possible to perform multiple fast-seeks using the same input file
[18:03:06 CEST] <wrs> eg with "ffmpeg -ss 10 -i input.mp4 -t 5 -ss 20 -i input.mp4 -t 5 output.mp4" I would 'expect' output.mp4 to have seconds 10-15 of input, then 20-25 of input. for a total of 10 seconds
[18:32:47 CEST] <cider> Does FFmpeg hold any kind of non CMD/shell interface, regardless of being a official/unofficial plugin? I am looking for a easy to read encoding/formats list, have had too much trouble using NLE's like Adobe Premiere/AfterEffects. I do most work in TF Nuke but that is mostly .avi ?
[18:34:36 CEST] <flux> cider, maybe there is, but perhaps ffprobe is useful to you, if you haven't noticed that one comes with ffmpeg
[18:40:41 CEST] <cider> Yea i just read its description, i am not in dire need right now, i will take a look. Will take some time. I am trying to plot my pipeline because running 3 program subscriptions will end in a yearly 3200 USD at best.
[19:05:54 CEST] <wrs> cider, if you're looking to extract information from media files: ffprobe -print_format json -show_format -show_streams input_file.mp4
[19:08:52 CEST] <cider> wrs, I was looking for a easy to use up-to-date encoding list, which would classify as free too. I do not think this is it but i am trying to take a look.
[19:15:13 CEST] <cider> flex, wrs Thanks guys and sorry for the slow reply, but this is not what i am looking for. Too hard for me. I think i recall someone i once knew, using this program to skip Adobe Premiere/AE.
[21:06:36 CEST] <medya> I keep getting   WARNING: library configuration mismatch on ubuntu for ffmpeg, and it keeps bugging me many codecs are not installed, is there a way to install ffmpeg correctly on ubuntu (16.04) with all the codecs ? the offical repos seem to suck
[21:26:11 CEST] <medya> I get this error when trying to ./configure from source " ERROR: gnutls not found using pkg-config"
[21:26:57 CEST] <medya> I am trying to build it on ubuntu 16.04
[21:31:24 CEST] <jkqxz> Install libgnutls-dev (or whatever the package is actually named).
[21:31:53 CEST] <furq> libgnutls28-dev
[21:33:50 CEST] <furq> medya: if you're getting "library configuration mismatch" then compile with --enable-static or remove ffmpeg/libav* from apt
[21:34:03 CEST] <furq> preferably the former
[21:44:25 CEST] <medya> ok thanks
[21:58:50 CEST] <Polochon_street> Hi ! I'm trying to update my code to the new version of ffmpeg; I changed my codec code to this http://sprunge.us/OjIP , but the codec_context is all wrong, without any error... Do you have any clue ?
[21:59:08 CEST] <medya> my make failed on "common.mak:60: recipe for target 'libavcodec/libopenh264enc.o' failed"
[22:03:41 CEST] <wallbroken> 32bit version and 64 will produce the same output?
[22:07:38 CEST] <medya> ok I gave up on compiling it myself, I am thinking to use a docker with ffmpeg on it.
[22:07:49 CEST] <medya> can I run ffmpeg on a docker on my host computer files?
[22:07:52 CEST] <medya> if yes how
[22:07:55 CEST] <Polochon_street> it's weird - I allocate and set the context properly, but every field of it is 0
[22:09:45 CEST] <furq> medya: what's wrong with the ffmpeg in apt
[22:09:54 CEST] <furq> it has all the codecs i care about other than fdk, and there are no binary distributions with fdk
[22:10:06 CEST] <furq> unless ubuntu have fucked it up, which wouldn't surprise me
[22:10:10 CEST] <jkqxz> wallbroken:  In general, yes.  There may be minor differences due to nondeterminism of some things, but they shouldn't affect the quality of the output.  (The speed of it certainly will change, though.)
[22:14:56 CEST] <wallbroken> jkqxz, "same output" means same hash on both the files
[22:15:37 CEST] <wallbroken> if i execute the same encoding two times in 32 bit mode, i get two identical files
[22:20:46 CEST] <furq> it depends on the codecs and settings used
[22:20:47 CEST] <jkqxz> It should be identical with most codecs, but I wouldn't be confident of saying that it is in all cases.  You should just try it with the codecs you are interested in.
[22:21:31 CEST] <furq> it's not really an ffmpeg question unless you're using internal encoders
[22:27:45 CEST] <medya> furq: the one in ap doesnt work for 264, I did everything everyone said always breaks
[22:27:49 CEST] <medya> and it is a very old ffmpeg
[22:27:51 CEST] <medya> it is like 2
[22:27:52 CEST] <medya> nt 3
[22:31:14 CEST] <furq> 2.8.6 isn't that old
[22:31:36 CEST] <furq> less than six months
[23:26:05 CEST] <samsonr> hello, I'm trying to push a live stream to a http server using ffmpeg. All works fine using the following command: ffmpeg -i /dev/video0 -f mpeg1video http://localhost/pub?id=1
[23:26:37 CEST] <samsonr> however I was curious if it's possible to configure ffmpeg to make a new http request for each data chunk
[23:26:54 CEST] <samsonr> atm it just keeps a long-lived connection and pushes the data
[23:27:31 CEST] <samsonr> I thought the flag '-multiple_requests 0' might help, but it seems not
[23:27:32 CEST] <samsonr> any ideaS?
[23:28:30 CEST] <Mavrik> That's a very strange question and even stranger choice of video codec.
[23:28:37 CEST] <Mavrik> Why do you need chunks?
[23:31:09 CEST] <samsonr> https://github.com/slact/nchan/issues/208
[23:31:31 CEST] <samsonr> I'm doing mpeg live streaming via websockets
[23:31:39 CEST] <samsonr> it actually works well for my needs :D
[23:31:56 CEST] <samsonr> for more info: http://phoboslab.org/log/2013/09/html5-live-video-streaming-via-websockets
[23:32:15 CEST] <samsonr> but the point is the server-side is written in node, also it's not really scalable
[23:32:41 CEST] <Mavrik> Just... no. :/
[23:32:51 CEST] <Mavrik> It'll also look terrible due to MPEG-1.
[23:33:06 CEST] <Mavrik> Use nginx rtmp plugin, stream to it via RTMP and let it distribute HLS/DASH
[23:33:24 CEST] <Mavrik> All pure HTTP supported by browsers.
[23:33:38 CEST] <samsonr> I can't use hls...I need the user to interact with the page
[23:33:54 CEST] <samsonr> I already run Wowza in parallel so that's not the issue, there s a HLS stream handy anyway
[23:34:51 CEST] <samsonr> anyway, that s beyond the point of my question :) So I assume it's not possible to push data in different reqs?
[23:35:09 CEST] <samsonr> I d think the only overhead would be sending the same headers over and over
[23:35:15 CEST] <samsonr> the handshake would be reused..
[23:36:10 CEST] <Mavrik> No, it's not really possible.
[23:36:22 CEST] <Mavrik> What would ffmpeg split the data on anyway?
[23:36:37 CEST] <Mavrik> It wasn't built for such use-case (unless the muxer supports it specifically)
[23:36:52 CEST] <samsonr> what's it splitting it now on?
[23:37:01 CEST] <Mavrik> It's not.
[23:37:07 CEST] <samsonr> ffmpeg -i /dev/video0 -f mpeg1video http://localhost/pub?id=1
[23:37:10 CEST] <Mavrik> It's a transcoder, it outputs data in a stream.
[23:37:24 CEST] <samsonr> when I do this, I get like 10 'data' events per sec
[23:37:26 CEST] <samsonr> from node
[23:37:33 CEST] <samsonr> it's a stream
[23:37:41 CEST] <samsonr> right
[23:43:02 CEST] <samsonr> then can you please explain what the "multiple_requests" flag does? I think its name doesn t make it clear
[23:45:21 CEST] <Mavrik> Sets HTTP header to `Connection: Keep-Alive` when connecting to server.
[23:46:09 CEST] <samsonr> thanks
[23:46:12 CEST] <Mavrik> (or Close, depending on the value)
[23:46:16 CEST] <Mavrik> Nothing else according to code grep.
[23:46:31 CEST] <Mavrik> Meant as a client option I guess.
[00:00:00 CEST] --- Sun Jul 31 2016


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