[Ffmpeg-devel-irc] ffmpeg.log.20150510

[burek]

[00:09:09 CEST] <RobotsOnDrugs> Cobra_Fast: q is not the same as crf
[00:10:28 CEST] <RobotsOnDrugs> and also, why are you using maxrate/bufsize with crf?
[00:11:34 CEST] <Cobra_Fast> because i'm realtime streaming
[00:12:08 CEST] <RobotsOnDrugs> then why use crf?
[00:12:48 CEST] <Cobra_Fast> my idea was to use only as much bandwidth as i need but cap it for the hbo logo
[00:13:44 CEST] <RobotsOnDrugs> i suppose
[00:14:45 CEST] <RobotsOnDrugs> anyway, you probably don't need to pay attention to q at all, but rather the bitrate and the quality you get for it
[00:15:01 CEST] <Cobra_Fast> alright, so i just need to have faith in it doing the right thing
[00:15:22 CEST] <RobotsOnDrugs> kind of
[00:15:32 CEST] <RobotsOnDrugs> you should look at the quality you get
[00:15:50 CEST] <RobotsOnDrugs> but q is not the same as crf, so don't expect them to match
[00:16:04 CEST] <Cobra_Fast> okay, thanks
[00:17:01 CEST] <RobotsOnDrugs> q is a more "objective" measurement of quality, whereas crf allows psychovisual stuff that will degrade quality to save bits in a way that you aren't likely to notice
[04:24:15 CEST] <casanova> How does an IRC channel work?
[04:24:41 CEST] <c_14> Magic electrons
[04:24:57 CEST] <casanova> Good enough for me.
[04:26:58 CEST] <klaxa> lol?
[04:29:30 CEST] <c_14> For all your important FFmpeg related questions.
[04:51:58 CEST] <trodis_> oh guys i need some help
[04:52:04 CEST] <trodis_> going almost crazy with ffserver
[04:52:51 CEST] <trodis_> i want to stream audio with as low delay as possible like this: ffmpeg <-> ffserver <-> mplayer / mpc / mpd e.t.c
[04:53:21 CEST] <trodis_> streaming does work, wether it is mp3, ac3 whatever but the delay is to much
[04:54:09 CEST] <trodis_> i dont know how i can reduce the delay, the buffering on the client side is turned off of course. I even tried libopus, but libopus has the biggest delay
[04:54:22 CEST] <trodis_> does someone has experience with this kind of problems?
[05:48:55 CEST] <casanova> Anyone good at compiling ffmpeg?
[05:50:11 CEST] <BtbN> gcc does a solid job at it
[05:50:20 CEST] <casanova> What is gcc?
[05:50:28 CEST] <BtbN> A C compiler.
[05:51:14 CEST] <casanova> I'm having issues with getting libfdk-acc and x264 together.
[05:54:48 CEST] <casanova> I had everything running good with the Jon Severson PPA and then I updated i t like a fool
[05:56:05 CEST] <casanova> brb
[06:03:47 CEST] <casanova> What triggers the "past duration x too large" messages in the newest version of FFMPEG?
[09:12:24 CEST] Action: messup hello mates....
[10:09:57 CEST] <messup> hello guys....
[10:10:28 CEST] <messup> i got stuck to concatenate videos in ffmpeg..
[10:13:39 CEST] <messup> i have a bunch a video with different codecs,container,size,sar and everything, but i wanna make them same codecs and parameter to use concat demuxer? what command  i use to achieve this? and its allright if have to add some black screen if aspect ratio not same.
[10:14:45 CEST] <messup> i cant find a really...really good command to make them exactly same? how to do that? thanks.
[11:40:05 CEST] <seasc> messup, have a look at: http://ffmpeg.org/ffmpeg-all.html#concat-2
[11:46:45 CEST] <messup> thanks seasc, but i think its concat protocol didnt work on mp4 files. but anyway i had managed to make a same codecs and its parameters as well but when i use concat demuxer the file is scretching when its play. why?? thanks
[11:51:38 CEST] <seasc> messup, yes, the example shows to use mpeg files, so you're best of converting all the related files to mpeg first
[11:52:12 CEST] <seasc> messup, uh no idea, never used conact but once, and i did what i just suggest to you
[11:53:26 CEST] <messup> thanks seasc. ok i try.
[11:54:43 CEST] <messup> do you actively make videos???
[11:56:27 CEST] <messup> i just wanna make some youtube videos with less effort, so i think it would be ffmpeg.
[12:01:00 CEST] <seasc> not atm, but planning to do so... but me wrote a linux script to handle most ffmpeg tasks i came across (ironicly its easier for me to write a script that handles 'complex' tasks, than doing them manualy)
[12:01:40 CEST] <seasc> It is a great choice, though, at times i cannot upload videos, hangs at youtube at somewhat around 95% :( not sure if its me or the video.
[12:04:49 CEST] <messup> oh you wrote a script, im planning to do so, but im new to ffmpeg so... need to dig around little bit. to make it most mostly less effort job as possible.hhhahhahha
[12:08:55 CEST] <messup> so what software you use to make a videos for youtube? i found openshot, but its damn slow when its come to rendering? so i m still searching the alternative....
[13:40:55 CEST] <trodis> i want to stream audio with as low delay as possible like this: ffmpeg <-> ffserver <-> mplayer / mpc / mpd e.t.c
[13:41:05 CEST] <trodis> streaming does work, wether it is mp3, ac3 whatever but the delay is to much
[13:41:12 CEST] <trodis> i dont know how i can reduce the delay, the buffering on the client side is turned off of course. I even tried libopus, but libopus has the biggest delay
[13:41:16 CEST] <trodis> does someone has experience with this kind of problems?
[17:04:06 CEST] <Zerowalker> What metdata date times can be stored via ffmpeg?
[17:04:26 CEST] <Zerowalker> and what does it translates to (creation_time == Encoded Date) i think for example
[19:25:00 CEST] <jrun> how do i change the colour depth of the output to say 256 (8-bit)?
[19:25:21 CEST] <jrun> sample_frmt? -vf format=something_here?
[19:25:35 CEST] <jrun> i have discovered format=gray so far but what are the other options?
[19:25:50 CEST] <jrun> how do i get a list of available formats?
[19:52:49 CEST] <techtopia> is there a way to pause an ffmpeg encoding job while it's running
[19:54:36 CEST] <klaxa> you can probably press ctrl+z in your shell if it supports that
[19:55:22 CEST] <c_14> techtopia: or just send SIGSTOP
[20:00:05 CEST] <techtopia> how do you send sigstop?
[20:00:32 CEST] <c_14> kill -SIGSTOP pid
[20:01:32 CEST] <techtopia> im on windows running it from command line
[20:07:17 CEST] <c_14> I have no idea how job control works on windows.
[20:08:01 CEST] <techtopia> yeah i don't think it's possible
[20:08:05 CEST] <techtopia> just wanted to double check
[20:27:40 CEST] <gr1sha> How can I fix this?
[20:27:40 CEST] <gr1sha> undefined reference to `av_frame_get_best_effort_timestamp'
[20:27:49 CEST] <gr1sha> I'm trying to comiple dranger's tut07
[20:28:54 CEST] <gr1sha> eran at eran-vm:~/Desktop$ gcc -o tutorial07 tutorial07.c -lavutil -lavformat -lavcodec -lswscale -lz -lm `sdl-config --cflags --libs`
[20:28:54 CEST] <gr1sha> tutorial07.c:(.text+0x15c1): undefined reference to `av_frame_get_best_effort_timestamp'
[20:28:54 CEST] <gr1sha> tutorial07.c:(.text+0x15f9): undefined reference to `av_frame_get_best_effort_timestamp'
[20:28:54 CEST] <gr1sha> collect2: error: ld returned 1 exit status
[20:29:29 CEST] <BtbN> What ffmpeg version are you using?
[20:30:41 CEST] <gr1sha> ffmpeg version 0.8.13-6:0.8.13-0ubuntu0.13.10.1,
[20:30:44 CEST] <gr1sha> O-o
[20:31:04 CEST] <BtbN> Well, that's simply too old.
[20:31:09 CEST] <gr1sha> yeah I can see now
[20:31:16 CEST] <gr1sha> how come 2.6.2 isn't available through apt-get?
[20:31:17 CEST] <BtbN> And propably not even ffmpeg, as it's ubuntu.
[20:31:29 CEST] <BtbN> Because you are using a very old ubuntu version.
[20:31:42 CEST] <BtbN> And because ubuntu has libav instead of ffmpeg.
[20:32:59 CEST] <gr1sha> jeez
[20:34:35 CEST] <gr1sha> what would you suggest?
[20:40:13 CEST] <gr1sha> BtbN, would it work on 15.04?
[20:40:28 CEST] <BtbN> No idea
[20:42:15 CEST] <gr1sha> I'll have to try, Thaknks a lot! :)
[21:47:25 CEST] <troy_s> gr1sha: Get a real FFMPEG is reasonable advice.
[21:48:02 CEST] <troy_s> gr1sha: Also, the tutorial is dead old, and much of the API has shifted quite dramatically.
[21:52:15 CEST] <gr1sha> troy_s, it was updated pretty recently and I'm using it because it's a requirment in a course I'm taking in the University
[22:00:49 CEST] <troy_s> gr1sha: Regardless, that error is telling you that the API is missing that function call. So you should update your local FFMPEG and see if the errors persist
[22:01:04 CEST] <gr1sha> I will, thanks!
[22:47:35 CEST] <koz_> What command would I need to use to convert a video encoded in AVC and contained in an MKV into a VP9 contained in webm? The sound is already encoded in a decent enough way, so I don't wanna change that.
[23:04:35 CEST] <JEEBsv> koz_: ffmpeg -i input.mkv -c:a copy -c:v libvpx-vp9 <any other libvpx vp9 options> output.webm
[23:36:22 CEST] <koz_> JEEBsv: What do you mean by the 'any other' part of that command?
[23:36:29 CEST] <koz_> Should I just literally put 'any other' there?
[23:37:03 CEST] <c_14> If you have special options that you want to give to libvpx you can put them there, but you don't have to.
[23:38:01 CEST] <koz_> Ah, ok. Thanks.
[23:40:06 CEST] <JEEBsv> like rate control, coding settings etc
[23:40:27 CEST] <JEEBsv> no idea how insane the defaults are for libvpx
[23:41:54 CEST] <DragonsLord> Hello!
[23:41:55 CEST] <DragonsLord> Does anybody know the best way to report FFmpeg a bug?
[23:42:24 CEST] <c_14> https://ffmpeg.org/bugreports.html
[23:42:40 CEST] <DragonsLord> Thank you c_14, pleased to read from you
[23:42:43 CEST] <DragonsLord> :)
[00:00:00 CEST] --- Mon May 11 2015