[Ffmpeg-devel-irc] ffmpeg.log.20161216

burek burek021 at gmail.com
Sat Dec 17 03:05:01 EET 2016


[05:30:56 CET] <KittyCat156> Any way to horizontally flip a video in ffmpeg without re-encoding but by using metadata?
[05:32:00 CET] <furq> you can rotate 180 degrees with metadata but i don't think you can flip
[05:33:28 CET] <KittyCat156> I know you can do a lot more by changing the displaymatrix, but AFAIK you can only read it through ffmpeg/probe
[05:33:38 CET] <KittyCat156> not write to it
[05:34:30 CET] <KittyCat156> *can -> could be able to, thought that sounded strange the way I worded it
[05:38:14 CET] <furq> it looks like there's code to set display matrices in libavutil
[05:38:23 CET] <furq> i don't know if ffmpeg exposes it though
[06:07:09 CET] <fahadash> When using two or more inputs, how can I refer to them separately in filter graph?
[06:07:11 CET] <fahadash> sorry I am a noob
[06:34:48 CET] <DHE> the first is [0:a] for preferred audio or [0:v] for preferred video or [0:1] for the stream that was labeled 0:1 in the console output
[06:34:59 CET] <DHE> and the second is similarly [1:a] or [1:v] or [1:1] etc
[06:42:03 CET] <fahadash> why two labels separated by a colon?
[06:42:13 CET] <fahadash> Why couldn't it just be [1] or [2] or [a]?
[06:56:11 CET] <DHE> file number, a colon, and a stream identifier.
[06:56:28 CET] <DHE> with 'v' and 'a' as convenience labels.
[08:37:28 CET] <gion> For this example filter ffmpeg -i input.mp4 -i logo.png -filter_complex "[0:v]scale=512:-1[bg];[bg][1:v]overlay=(w-ow)/2:(h-oh)/2"  is there any way to affect the graph while it runs ? I want to control the w and ow from a websocket server, anything on how to approach this problem ?
[08:45:44 CET] <ferdna> gion, sounds complicated
[08:46:03 CET] <ferdna> you could do it with php
[08:47:15 CET] <DHE> yeah, sounds like you need to do some API stuff. there are some triggerable filter commands during execution via stdin, but it's limited
[08:48:32 CET] <gion> I know gstreamer is something more proper for this, but it is quite heavy compared to just the ffmpeg binary
[08:49:01 CET] <ferdna> i always had problems with gstreamer
[08:51:59 CET] <sunny_26_> Hi I wanna submit a patch to ffmpeg
[08:52:16 CET] <sunny_26_> How can I summit a patch using git --send-email ?
[08:52:41 CET] <sunny_26_> Like how to write body and subject to it ?
[08:52:49 CET] <sunny_26_> I am unaware of it
[08:52:55 CET] <sunny_26_> please help
[08:54:27 CET] <sunny_26_> and I have to submit patch to "ffmpeg-devel at ffmpeg.org" ! is that correct ?
[08:55:31 CET] <ferdna> sunny_26_, if you dont know how to do that... please refrain from do it so...
[08:56:08 CET] <ferdna> from doing it
[08:59:21 CET] <DHE> or at least email yourself first to make sure it turns out okay.
[09:03:38 CET] <ferdna> sunny_26_, get an account github.com...
[09:03:47 CET] <ferdna> then fork the code you are going to modify
[09:04:02 CET] <ferdna> submit it.. and you are done...
[09:04:03 CET] <ferdna> https://github.com/FFmpeg/FFmpeg
[09:04:09 CET] <ferdna> that is the github repo for ffmpeg
[09:19:07 CET] <ferdna> markvandenborre, you here?
[09:19:26 CET] <ferdna> llamapixel, you here?
[09:22:46 CET] <sunny_26_> "Patches should be submitted to the ffmpeg-devel mailing list using git format-patch or git send-email. Github pull requests should be avoided because they are not part of our review process and will be ignored."
[09:44:00 CET] <markvandenborre> ferdna: what's your question?
[09:44:50 CET] <ferdna> sunny_26_, ohh cool.. i didnt know that... sorry i dont submit patches to ffmpeg
[09:44:57 CET] <ferdna> markvandenborre, can i priv msg?
[09:45:12 CET] <durandal_1707> sunny_26_: yout can attach patches to mail instead
[09:46:01 CET] <ferdna> sunny_26_, https://git-scm.com/docs/git-format-patch
[09:49:27 CET] <ferdna> https://robots.thoughtbot.com/send-a-patch-to-someone-using-git-format-patch
[09:54:10 CET] <ferdna> good night must go to bed
[09:54:11 CET] <ferdna> =S
[10:18:12 CET] <sunny_26_> durandal_1707 : Can i send my patch directly to ffmpeg-devel at ffmpeg.org Using my outlook ? I have already registered to ffmpeg-devel.
[10:19:00 CET] <durandal_1707> sunny_26_: yes
[10:19:45 CET] <sunny_26_> Ok
[10:20:03 CET] <sunny_26_> But what does this statement means "Is the mime type of the patch correct? It should be text/x-diff or text/x-patch or at least text/plain and not application/octet-stream. " ?
[10:20:29 CET] <sunny_26_> I am following https://ffmpeg.org/developer.html#Submitting-patches-1
[10:20:54 CET] <durandal_1707> ignore it if you can't follow
[10:21:25 CET] <sunny_26_> So they will accept my patch ? Or atleast reply back !
[10:21:50 CET] <sunny_26_> and I must send it to "ffmpeg-devel at ffmpeg.org" ? Right !
[10:22:49 CET] <sunny_26_> durandal_1707, Is my understanding is correct !
[10:23:58 CET] <sunny_26_> Hi u there ?
[10:56:19 CET] <karklud> \msg NickServ identify ken12damaer
[10:56:35 CET] <karklud> doh
[11:09:26 CET] <kerio> karklud: nice
[11:09:45 CET] <karklud> kerio, i'm wwaaayy to tired to be at work now........
[11:13:33 CET] <karklud> kerio, but it just showed up liked *******, right??
[11:26:45 CET] <kerio> karklud: ofc
[11:26:53 CET] <kerio> you can ken12damaer my ken12damaer
[11:30:35 CET] <durandal_1707> it's now logged and available to everyone
[11:31:10 CET] <karklud> that's good, i'll never forget it then
[11:32:09 CET] <karklud> kerio, wait i just realized that there's a typo in there...
[11:32:16 CET] <kerio> phew!
[11:32:32 CET] <karklud> (i wish)
[13:22:23 CET] <chaks> Hello, everybody!
[13:23:17 CET] <chaks> Can anyone assets me for my problem using ffmpeg?
[16:36:28 CET] <kerio> does youtube understand ffvhuff
[16:37:40 CET] <furq> there's only one way to find out
[16:38:24 CET] <kerio> yes
[16:38:27 CET] <kerio> asking about it in #ffmpeg
[16:38:38 CET] <kerio> :^)
[16:38:59 CET] <JEEB> it should understand it
[16:39:07 CET] <JEEB> at least whatever lavc could encode in 2011
[16:39:17 CET] <JEEB> because I think that's the version of FFmpeg they're using
[16:44:41 CET] <kerio> bitrate: 1240640 kb/s
[16:44:43 CET] <kerio> ay dios mio
[16:46:17 CET] <kerio> ...how did i manage to put 0rgb into huffyuv
[16:46:24 CET] <kerio> i thought the "yuv" part implied yuv
[16:53:35 CET] <kerio> JEEB: yuv444p gets compressed MUCH harder than rgb24
[16:53:44 CET] <kerio> even though it should be roughly the same info
[17:02:03 CET] <furq> it's probably packed
[17:02:17 CET] <kerio> ur packed
[17:02:31 CET] <kerio> hm is there a packed rgb format
[17:02:44 CET] <furq> most of them are packed
[17:02:56 CET] <kerio> er
[17:02:57 CET] <kerio> a planar
[17:03:02 CET] <furq> gbrp is the only planar one i know of
[17:07:45 CET] <kerio> why is it gbr
[17:07:46 CET] <kerio> instead of rgb
[17:11:07 CET] <durandal_1707> kerio: that's way how it's coded in first codec using planar format
[17:11:23 CET] <kerio> anyway planar rgb didn't help the compression
[17:11:27 CET] <kerio> with ffvhuff
[17:11:50 CET] <durandal_1707> because it doesn't support it directly
[17:12:14 CET] <kerio> holy crap ffv1 is so much better with it
[17:12:30 CET] <kerio> (in bgr0 mode, apparently)
[17:12:53 CET] <kerio> (gbrp is not compatible with ffv1 :( )
[17:13:30 CET] <kerio> 1235691 kb/s vs 273357 kb/s
[17:13:38 CET] <kerio> ffv1 doesn't achieve realtime here tho :(
[17:38:13 CET] <durandal_1707> kerio: are you on toaster?
[17:38:26 CET] <kerio> 2880x1800p60
[17:38:30 CET] <kerio> :3
[17:54:39 CET] <durandal_1707> kerio: utvideo? I could mention magicyuv but there's no encoder in ffmpeg for it
[18:02:35 CET] <durandal_1707> there's also vc1 iirc
[20:00:39 CET] <norbert> hi all, I'm on Linux and from what I'm reading I need a "tainted" ffmpeg to get the WebM profile(s) in the kdenlive video editor; anyone here know the apt - or other - command to get this "tainted" ffmpeg?
[20:04:25 CET] <relaxed> norbert: you mean avconv?
[20:05:04 CET] <relaxed> (the ffmpeg fork)
[20:05:27 CET] <norbert> I don't know
[20:05:37 CET] <norbert> "You might be missing tained ffmpeg and it's libraries." is what someone wrote here https://forums.mageia.org/en/viewtopic.php?f=7&t=10014
[20:05:51 CET] <norbert> in a topic "no webm rendering on kdenlive"
[20:06:46 CET] <relaxed> yeah, I have no idea then.
[20:07:41 CET] <relaxed> norbert: try my build and see if it works: https://www.johnvansickle.com/ffmpeg/
[20:07:48 CET] <kerio> "tainted" is a little harsh
[20:09:00 CET] <furq> apparently "tainted" is the name of the mageia repo which contains patented codecs
[20:09:14 CET] <furq> so if you're on a debian-alike it's probably meaningless
[20:09:43 CET] <relaxed> oh, I thought it was more libav trashing :)
[20:09:56 CET] <furq> https://wiki.mageia.org/en/Archive:_Mageia_3_Release_Notes#The_Mageia_online_repositories
[20:10:10 CET] <furq> not sure why that would affect webm though
[20:13:31 CET] <norbert> hm, yeah, I'd think webm would be a free format
[20:17:49 CET] <norbert> I installed the ubuntu-restricted-* packages, but that didn't fix it
[20:20:09 CET] <norbert> I'm probably missing an entire apt repo with the non-free software or something
[20:22:26 CET] <norbert> nope, I have multiverse in the apt config file
[20:23:24 CET] <norbert> is there any other way to get a 'full' ffmpeg without asking people if they can share a customly compiled binary?
[20:51:17 CET] <nodeclear5> http://ilredentore.dynv6.net regards...
[22:31:49 CET] <julienbcn> Hello all, i'm looking for a ffmpeg command or a bash script which can extract 15 thumbs from a video mp4 (basing on duration), anyone for help please?
[23:05:48 CET] <norbert> hi again, I've decided to just export the kdenlive video to mp4, and then use ffmpeg to convert from mp4 to webm
[23:05:59 CET] <norbert> my question now is, how can I get the absolute best webm quality?
[23:06:36 CET] <norbert> I did see https://trac.ffmpeg.org/wiki/Encode/VP8 (and VP9)
[23:06:48 CET] <norbert> but it's unclear to me what I should do to get the highest possible quality
[23:07:05 CET] <norbert> I could set, for instance, a constant bitrate, but then how high should it be?
[23:07:14 CET] <norbert> 2M, 10MB?
[23:11:21 CET] <furq> you probably want -b:v 0 -crf 30
[23:11:25 CET] <furq> tune the crf value as needed
[23:11:45 CET] <furq> also obviously going from mp4 to webm will lose quality unless you're using lossless h264 or something
[23:13:07 CET] <DHE> you can't improve on the image quality of the original by reprocessing the video
[23:16:03 CET] <norbert> yes, I wish kdenlive could render to webm, but I need to work with what I've got :)
[23:16:13 CET] <norbert> I'll try what you suggested
[23:18:30 CET] <furq> if you have enough disk space you could render to ffv1 or something and then create the mp4 and webm from that
[23:18:59 CET] <furq> from a brief look at the manual kdenlive doesn't support just piping yuv to stdout, because it's an NLE and life should be painful
[23:20:31 CET] <norbert> ffv1... should this be listed inside kdenlive? it's not listed for me
[23:20:55 CET] <norbert> the webm output by the way contains short millisecond blinks that mean I cannot use it this way
[23:21:04 CET] <norbert> also the quality simply isn't good enough for me, I'm afraid
[23:22:13 CET] <norbert> oh wait, I see it
[23:22:16 CET] <norbert> I had to change the destination
[23:22:38 CET] <norbert> and now I also see everything else, including WebM
[23:22:40 CET] <norbert> so problem solved
[23:22:45 CET] <norbert> but man, not userfriendly IMO
[23:22:52 CET] <norbert> anyway, thanks for all the feedback and such
[00:00:00 CET] --- Sat Dec 17 2016


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