[Ffmpeg-devel-irc] ffmpeg.log.20151210

burek burek021 at gmail.com
Fri Dec 11 02:05:01 CET 2015


[05:40:45 CET] <cluelessperson> could someone help me figure out why ffserver is producing.... https://cluelessperson.com/stream/server/1.webm ?
[05:41:11 CET] <cluelessperson> specifically, it's stutt er ing, an d tha ts ann oy ing
[05:41:41 CET] <cluelessperson> Seems it stops happening when there's less activity occurring
[05:45:14 CET] <chungy> I think you might have answered your own question
[05:45:42 CET] <cluelessperson> chungy, not really?
[05:45:46 CET] <cluelessperson> would that be bitrate?
[05:46:09 CET] <cluelessperson> chungy, and by less activity, I mean less occuring in the movie, less action
[05:46:40 CET] <chungy> Ah hm, I assumed you meant it was streaming live
[06:21:56 CET] <cluelessperson> chungy, this movie is streaming, live
[06:22:07 CET] <cluelessperson> chungy, ffmpeg -> ffserver -> you
[07:02:26 CET] <shakirz1> hi everyone
[07:02:49 CET] <shakirz1> i m getting issue in ffmpeg multicast stream with muliple channels
[07:03:00 CET] <shakirz1> http://pastebin.com/HrUwnFQX
[07:03:14 CET] <shakirz1> see my ffprobe and ffmpeg command line
[07:03:35 CET] <shakirz1> plz anyone can help me to resolve this issue ?
[07:20:53 CET] <shakirz1> hi everyone
[07:21:02 CET] <shakirz1> i m getting issue in ffmpeg multicast with multiple channels
[07:21:10 CET] <shakirz1>  http://pastebin.com/HrUwnFQX
[07:21:17 CET] <shakirz1>  anyone can help me to resolve this issue
[08:00:29 CET] <tommd> Is specifying the framerate required for camera capture?  I'm noticing both from the API and the CLI I get apparently uninitialized framerate fields and thus failed capture.
[08:00:43 CET] <tommd> If I manually specify the exact framerate supported then I'm good to go.
[08:13:49 CET] <flux> tommd, well, isn't that the answer then?-)
[08:20:05 CET] <tommd> flux: Well it doesn't generalize well.
[08:20:20 CET] <tommd> In my library I can't really guess the framerate for the users hardward.
[08:20:53 CET] <tommd> so I guess there must be a way to query the available devices so I can correctly set the framerate.
[08:24:33 CET] <tommd> flux: My origional question was more "is the failure with no set framerate a bug"
[08:25:42 CET] <tommd> I think this failure should be regarded as a bug.  Failure as a default, when the valid value is known, only seems to make sense if a conflicting value was set manually by the user.
[08:36:42 CET] <flux> I would classify it as a missing feature
[08:37:01 CET] <flux> I bet code submissions to address that would be acceptable :)
[08:44:19 CET] <tommd> great
[08:48:51 CET] <yongyung> ffmpeg -r 180 -i "clip01%%04d.tga" -c:v libx264 -preset veryfast -qp 12 -pix_fmt yuv420p -movflags +faststart -tune fastdecode "clip01.mp4"
[08:48:56 CET] <yongyung> This is what I'm using to convert frames for editing, but I always get millions of "past duration too large" messages - I know it's just a warning but doesn't that still mean that I'm doing something wrong? Is there a way to fix that or to make ffmpeg at least shut up with the warnings while still showing the normal progress info?
[08:54:08 CET] <relaxed> yongyung: use -framerate instead of -r
[08:54:57 CET] <yongyung> relaxed: Hm, that did the trick. Is there any difference?
[08:56:43 CET] <relaxed> yes, the image2 demuxer takes -framerate
[08:58:34 CET] <relaxed> as for -r, http://ffmpeg.org/ffmpeg-all.html#Video-Options
[08:59:50 CET] <yongyung> So... is the output any different?^^
[09:01:24 CET] <yongyung> relaxed: I'm just wondering if there's a reason for me to reconvert some old footage or not
[09:03:21 CET] <relaxed> Using -r might cause framerate issues. Compare the outputs of the two.
[10:40:13 CET] <shakirz1545> Is there anyone who can help me for ffmpeg multicast streaming ?
[10:44:41 CET] <waressearcher2> shakirz1545: hallo
[10:44:47 CET] <shakirz1545> yes
[10:45:02 CET] <waressearcher2> shakirz1545: wie geht's ?
[10:46:10 CET] <shakirz1545> problem is that I m getting multiple channels from single link and try to convert it in mp4 file but its show me error
[10:46:16 CET] <shakirz1545> http://pastebin.com/HrUwnFQX
[10:51:51 CET] <shakirz1545> me fine
[10:54:18 CET] <shakirz1545> Mir geht es gut
[10:54:40 CET] <shakirz1545> werden Sie mir helfen, Ordnung in dieses Problem?
[10:55:17 CET] <waressearcher2> ich weiß nicht
[10:55:25 CET] <shakirz1545> mit Google Translate
[10:56:08 CET] <shakirz1545> OK danke
[11:03:41 CET] <dsl420> lol.. waressearcher2 ist dir langweilig? jeden hier auf deutsch zu begrüßen ist zwar nett, aber doch etwas merkwürdig ;) gibt bestimmt bessere kanäle als #ffmpeg für deutschen smalltalk :)
[11:04:28 CET] <furq> dsl420: hallo
[11:04:38 CET] <dsl420> hi
[11:57:56 CET] <shakirz1> Gibt es jemanden, der mir helfen kann, meine ffmpeg Multicast-Problem zu beheben
[12:27:13 CET] <dsl420> :)
[15:45:23 CET] <m0e> Hello, is this the right place/channel to ask about cross-compiling ffmpeg with librtmp support for a raspberry pi?
[15:49:46 CET] <waressearcher2> m0e: hallo
[15:57:22 CET] <m0e> waressearcher2: Im trying to follow this tutorial http://help.dacast.com/hc/en-us/articles/202357380-Stream-on-DaCast-under-Linux-with-ffmpeg but I dont want to compile it on the raspbery pi directly, so I bought a DigitalOcean 16 core instances to do the job
[15:57:43 CET] <m0e> so Im following this guide https://trac.ffmpeg.org/wiki/CompilationGuide/RaspberryPi
[15:57:47 CET] <m0e> to cross-compile
[15:58:20 CET] <m0e> I have multiple raspberry pi that needs to live stream
[15:58:29 CET] <m0e> using rtmp
[15:59:49 CET] <m0e> my problem is when I try to run the execute the configure script, I get ERROR: librtmp not found using pkg-config
[16:00:23 CET] <m0e> to execute*
[16:00:44 CET] <Bombo> m0e: did you compile that and install?
[16:01:30 CET] <m0e> wel yes, but I think because I didnt use the cross-compiler Bombo
[16:01:48 CET] <m0e> I tried to use the cross-compiler with librtmp
[16:02:12 CET] <Bombo> m0e: of course you need to compile it the same way
[16:02:16 CET] <m0e> but I kept having a problem that openssl is missing
[16:02:47 CET] <Bombo> m0e: and then point PKG_CONFIG_PATH to the lib dir where pkgconfig files are
[16:03:14 CET] <Bombo> m0e: then compile that too, welcome in dependency hell ;)
[16:03:28 CET] <m0e> my god...
[16:03:55 CET] <m0e> ok, gonna try that
[16:04:07 CET] <Bombo> (if you need ssl that is)
[16:04:31 CET] <Bombo> (if not you could probably disable it in configure --disable-openssl or something)
[16:06:25 CET] <m0e> I need it to work
[16:06:27 CET] <m0e> nothing more
[16:06:34 CET] <m0e> second day trying to get it work
[16:07:14 CET] <waressearcher2> so süß
[16:16:55 CET] <furq> m0e: which rpi
[16:17:06 CET] <m0e> furq: rpi 2
[16:17:40 CET] <m0e> if theres a better solutiom to stream from the pi camera over rtmp to a server
[16:17:47 CET] <furq> you can install regular debian jessie on an rpi2
[16:17:53 CET] <furq> which has ffmpeg with librtmp support in the repos
[16:18:28 CET] <m0e> aha
[16:18:48 CET] <m0e> I want something like
[16:18:49 CET] <m0e> ```
[16:18:53 CET] <m0e> ffmpeg -re -f lavfi -i testsrc -c:v libx264 -b:v 500k -an -s 1920x1080 -x264opts keyint=50 -g 25 -pix_fmt yuv420p -f flv "rtmp://p.ep246802.i.akamaientrypoint.net/EntryPoint flashver=FMLE/3.0\20(compatible;\20FMSc/1.0) live=true pubUser=123456 pubPasswd=789123 playpath=dclive_1_1 at 246802"
[16:19:03 CET] <m0e> it relies on rtmpdump I guess?
[16:19:20 CET] <m0e> Im using their service for a project
[16:19:53 CET] <m0e> and I have multiple raspberry pis live streaming
[16:21:31 CET] <furq> are you running that command on the rpi?
[16:21:49 CET] <furq> i can't imagine an rpi2 is going to get close to 25fps encoding 1080p x264
[16:22:09 CET] <m0e> no no, ignore the values
[16:22:19 CET] <m0e> max 640
[16:22:23 CET] <m0e> and 15-20fps
[16:22:44 CET] <m0e> I meant about the rtmp field
[16:22:52 CET] <furq> yeah that part should be fine
[16:23:05 CET] <m0e> ok, will give it a shot
[16:23:12 CET] <furq> http://sjoerd.luon.net/posts/2015/02/debian-jessie-on-rpi2/
[16:23:12 CET] <m0e> default ffmpeg from their repo yes?
[16:23:20 CET] <furq> there's a jessie image available there
[16:23:28 CET] <furq> there are probably others, i just debootstrapped mine
[16:24:18 CET] <furq> and yeah regular ffmpeg from the repo should be fine
[16:24:27 CET] <m0e> aha
[16:24:31 CET] <furq> unless they only added rtmp support in testing, which seems unlikely
[16:26:32 CET] <Bombo> http://www.raspbian.org/
[16:26:44 CET] <m0e> I hope so, downloading it right now
[16:26:46 CET] <m0e> raspbian doesnt provide ffmpeg
[16:26:49 CET] <furq> ^
[16:26:58 CET] <furq> there's no reason to use raspbian on an rpi2
[16:27:04 CET] <m0e> true
[16:27:13 CET] <Bombo> i got it on rpi1
[16:27:14 CET] <furq> it only exists because debian armhf doesn't run on armv6
[16:27:17 CET] <Bombo> its jessie too
[16:27:57 CET] <furq> you can't install debian jessie armhf packages on it though
[16:28:01 CET] <furq> they're compiled for armv7
[16:28:06 CET] <Bombo> i compiled ffmpeg on it when i had raspbian wheezy, took ~7h ;)
[16:28:19 CET] <Bombo> didn't try it on the new one yet
[16:28:33 CET] <m0e> furq: question, cant I use debians jessie repo to install ffmpeg?
[16:28:45 CET] <furq> on raspbian?
[16:28:46 CET] <m0e> on the current os
[16:28:48 CET] <furq> i have no idea, i've never used it
[16:28:48 CET] <m0e> yes
[16:28:55 CET] <furq> you might be able to
[16:29:31 CET] <furq> mixing debian repos is generally a quick path to dependency hell, though
[16:30:08 CET] <m0e> furq: from debians wiki Be carrefull, FFmpeg is not available on Debian 8 Jessie, to find out in which deposit the package is available, look here debpkg:libav or here debpkg:ffmpeg . It also possible to compile it by following the instructions available here: https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu
[16:30:35 CET] <furq> it's in jessie-backports, or you can upgrade inplace to testing
[16:31:04 CET] <furq> https://packages.debian.org/jessie-backports/ffmpeg
[16:42:51 CET] <m0e> furq: installing on raspbian on, from their repo
[16:43:03 CET] <m0e> but it doesnt seem it require librtmp
[16:43:05 CET] <m0e> required*
[16:43:17 CET] <furq> i think librtmp is a build dependency
[16:44:02 CET] <m0e> mmm
[16:49:29 CET] <welpo> If I'm getting "Unknown encoder 'libvpx'" it means I'm missing that encoder, right? (not sure if docs are outdated for my version)
[16:51:15 CET] <welpo> Yeah I forgot to compile with --enable-libvpx
[16:51:37 CET] <furq> m0e: ignore that, librtmp is a dependency of libavformat
[16:51:57 CET] <furq> but weirdly on debian it's a dependency of libcurl so you probably already have it installed
[16:52:23 CET] <m0e> furq: it turned out its installed
[16:52:33 CET] <m0e> thanks, now to get the right command working
[16:52:57 CET] <m0e> this is the default command, which needs tweaking
[16:53:19 CET] <m0e> raspivid -n -vf -hf -t 0 -w 640 -h 360 -fps 20 -b 500000 -o - | ffmpeg -i - -vcodec copy -an -pix_fmt yuv420p -f flv "rtmp://p.ep394357.i.akamaientrypoint.net/EntryPoint flashver=FMLE/3.0\20(compatible;\20FMSc/1.0) live=true pubUser=210210 pubPasswd=124279 playpath=dclive_1_150 at 394357"
[16:53:54 CET] <m0e> so I need to pipe from raspivid
[16:54:08 CET] <m0e> not sure about the -pix_fmt though
[16:56:02 CET] <m0e> euhm
[16:56:06 CET] <m0e> getting *** Error in `ffmpeg': double free or corruption (!prev): 0x00d01f60 ***
[17:01:43 CET] <furq> m0e: maybe because of mixing armv6 and armv7 packages
[17:02:25 CET] <m0e> oh better now, seems its fixed
[17:02:25 CET] <m0e> RTMP_Connect1, handshake failed.
[17:02:25 CET] <m0e> I tweaked the args a bit
[17:07:25 CET] <welpo> I'm getting "ERROR: libvpx decoder version must be >=0.9.1" when compiling with --enable-libvpx. I followed https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu#libvpx exactly, what am I doing wrong?
[17:07:43 CET] <shahriman> m0e: I recommend instead of piping use V4L2.
[17:08:01 CET] <shahriman> It is simpler to use.
[17:08:43 CET] <TD-Linux> welpo, well 1.4.0 is old, you probably want 1.5.0 now
[17:08:43 CET] <c_14> welpo: upload your config.log to a pastebin site and link here
[17:08:56 CET] <shahriman> Using raspi-config enable the camera, then `sudo modprobe bcm2835_v4l2`. Afterwards, you can run "ffmpeg -i /dev/video0 ..." to read from your camera.
[17:09:15 CET] <welpo> might be old, TD-Linux, but compiler is asking for >0.9.1, which it is
[17:09:17 CET] <welpo> c_14: okay, sec
[17:09:44 CET] <welpo> here is my config.log, c_14: https://welpo.me/nani/config.txt
[17:11:21 CET] <c_14> welpo: Did you export PKG_CONFIG_PATH?
[17:12:10 CET] <m0e> shahriman: thank you
[17:12:14 CET] <m0e> will check it out now
[17:13:26 CET] <m0e> shahriman: I got *** Error in `ffmpeg': free(): invalid next size (normal): 0x01cbd230 ***
[17:13:30 CET] <welpo> c_14: No. Trying again
[17:14:20 CET] <shahriman> m0e: Just to be sure, are you using debian package or did you build yourself?
[17:14:30 CET] <m0e> no, I used the debian package
[17:14:58 CET] <m0e> thats what I get when I first run ffmpeg
[17:15:00 CET] <m0e> fmpeg version 2.8.1-1~bpo8+1 Copyright (c) 2000-2015 the FFmpeg developers
[17:15:01 CET] <m0e>   built with gcc 4.9.2 (Debian 4.9.2-10)
[17:15:02 CET] <m0e>   configuration: --prefix=/usr --extra-version='1~bpo8+1' --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/arm-linux-gnueabihf --incdir=/usr/include/arm-linux-gnueabihf --enable-gpl --enable-shared --disable-stripping --disable-decoder=libopenjpeg --disable-decoder=libschroedinger --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite
[17:15:03 CET] <m0e> --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-openal --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libsnappy --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid
[17:15:03 CET] <m0e> --enable-libzvbi --enable-opengl --enable-x11grab --enable-libiec61883 --enable-libdc1394 --enable-libzmq --enable-frei0r --enable-libx264 --enable-libopencv
[17:15:27 CET] <c_14> m0e: more than 3 lines of output to a pastebin service please
[17:15:44 CET] <m0e> c_14: sorry, will do next time
[17:19:02 CET] <shahriman> m0e: What do you get when you run `ffmpeg -i /dev/video0 -f null -`? Do you still get the error?
[17:19:30 CET] <m0e> shahriman: no it works fine
[17:20:05 CET] <m0e> if I do the same but with teh -f flag, I get Segmentation fault
[17:21:05 CET] <shahriman> m0e: What do you mean?
[17:21:38 CET] <m0e> shahriman: ffmpeg -i /dev/video0 -f flv rtmp data
[17:22:08 CET] <m0e> Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1024x768, 283115 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
[17:22:08 CET] <m0e> Segmentation fault
[17:22:16 CET] <shahriman> m0e: can you write a local file?
[17:22:27 CET] <shahriman> ffmpeg -i /dev/video0 -f flv local_file.flv
[17:22:56 CET] <m0e> yes it works
[17:24:22 CET] <furq> m0e: like i said it's probably because ffmpeg is armv7 on an armv6 base system
[17:24:40 CET] <m0e> furq: raspberry pi 2 is armv7
[17:24:44 CET] <m0e> Im on a rpi2
[17:24:48 CET] <shahriman> RPi 2 is not armv6
[17:24:54 CET] <furq> yeah but raspbian packages are compiled for armv6
[17:24:58 CET] <m0e> mmm
[17:25:00 CET] <shahriman> He is on Debian.
[17:25:08 CET] <furq> no he isn't
[17:25:10 CET] <m0e> no, Im raspbian using debian jessie packages
[17:25:15 CET] <m0e> on raspbian*
[17:25:15 CET] <shahriman> Ah
[17:25:21 CET] <shahriman> Why are you doing that?
[17:25:27 CET] <furq> i guess he didn't want to reinstall
[17:29:44 CET] <shahriman> furq: Packages compiled for armv6 should work fine on armv7 though, no?
[17:30:21 CET] <furq> yeah, but if you're getting segfaults from debian packages then mixing armv6 and armv7 packages would be the first thing i'd suspect
[17:31:56 CET] <welpo> Configured now without problems, c_14. Thanks!
[17:39:40 CET] <welpo> I want to hide the "Stream #0.0 -> #0.0", size and video info when I run ffmpeg (to integrate it in my scrips). Even when using -loglevel quiet that still shows. What can I do? ffmpeg version is 0.8.17-6:0.8.17-1
[17:39:55 CET] <m0e> ok, I seems like that issue happens randomly
[17:39:59 CET] <m0e> now, I tried it again
[17:40:02 CET] <m0e> I got
[17:40:07 CET] <m0e> "PublisherAuth, Authentication failed: unknown auth mode: [ AccessManager.Reject ] : [ authmod=adobe ] : ?reason=cannot_load_password_file
[17:40:08 CET] <m0e> rtmp server requested close
[17:40:32 CET] <c_14> welpo: eeeeeeeh, didn't you just compile from git?
[17:41:00 CET] <c_14> did you set path, execute using the full path?
[17:41:16 CET] <welpo> c_14: I'm compiling for my own usage, but I'm not the only one using this script so I want to make it compatible with other systems (in this case, the Debian package for ffmpeg)
[17:41:34 CET] <welpo> (it's still compiling, so I'm using the system's ffmpeg and just now noticed this)
[17:42:06 CET] <c_14> That's not ffmpeg from FFmpeg. It's an outdated broken thingy from libav
[17:42:12 CET] <c_14> New debian versions should have ffmpeg
[17:42:21 CET] <welpo> hm
[17:42:45 CET] <c_14> you can maybe get it from backports
[17:42:53 CET] <welpo> it disappeared from jessie so I think the system is using https://packages.debian.org/wheezy/ffmpeg
[17:43:08 CET] <welpo> in any case, I don't want to update the system's ffmpeg, but rather: Is there any way to silence THIS version of ffmpeg?
[17:43:58 CET] <c_14> It's in stretch and jessie-backports
[17:44:03 CET] <c_14> And I don't know
[17:44:08 CET] <c_14> other that 2&>/dev/null
[17:45:04 CET] <welpo> yeah, that's what I'll do I guess
[20:12:43 CET] <satt> Hey guys, trying to center inputs if required using (ow-iw)/2:(oh-ih)/2 as a pad argument, but sometimes I'm getting a negative value which doesn't work
[20:13:05 CET] <satt> Here's an example of a command
[20:13:18 CET] <satt> ffmpeg -i input1.mp4 -i input2.mp4 -filter_complex [0:v]scale=if(gt(ih\,iw)\,-2\,374):if(gt(ih\,iw)\,668\,-2),pad=374:668:(ow-iw)/2:(oh-ih)/2,setsar=sar=1/1[v0]; [1:v]scale=if(gt(ih\,iw)\,-2\,374):if(gt(ih\,iw)\,668\,-2),pad=374:668:(ow-iw)/2:(oh-ih)/2,setsar=sar=1/1[v1]; [v0] [0:a:0] [v1] [1:a:0] concat=n=2:v=1:a=1 [v] [a] -map [v] -map [a] output.mp4
[20:14:14 CET] <satt> Here's the error on the pad - [Parsed_pad_1 @ 0x7f8511408480] Negative values are not acceptable.
[20:16:00 CET] <kepstin> hmm. so something's gone wrong where either the height or width or the scale output is too big
[20:16:33 CET] <kepstin> which makes sense, since your if(gt(ih,iw) is checking whether the video is wider/narrower than a square, but you're resizing to a rectangle
[20:18:40 CET] <satt> That's what I figured - but I'm not sure how to go about fixing it - I'm new to ffmpeg.  Basically I have to concatenate a lot of videos that might be in different resolutions
[20:20:50 CET] <kepstin> what an odd output size, width=374, height=668?
[20:21:29 CET] <satt> portrait video content, shot on a phone
[20:21:45 CET] <kepstin> anyways, you should rewrite the condition to do if(gt(iw/ih,374/668) to make it relative to the ratio you want rather than square
[20:21:45 CET] <satt> I'm taking the smallest dimensions of the inputs
[20:21:50 CET] <kepstin> that would probably be sufficient.
[20:22:17 CET] <satt> alright great thanks, I'll give that a try
[20:22:24 CET] <satt> appreciate the help!
[20:23:27 CET] <kepstin> and try the scale filter on its own without the pad to make sure it's giving you the dimensions you want on a bunch of test input files.
[20:27:54 CET] <satt> kepstin: Thanks yeah I'll definitely test that out too
[21:17:37 CET] <shevy> I am using ffmpeg to cut a .mp3 file; is there a way to tell ffmpeg to retain the original audio bitrate?
[21:18:09 CET] <shevy> The command I use right now is something like this: ffmpeg -i foobar.mp3 -ss 00:00:5.000 -t 00:05:53.000 output.mp3
[21:19:22 CET] <shevy> I noticed that the initial recording was 192.0 kbit/13.61%; the new file however was 128.0 kbit/9.07%, I assume that ffmpeg may have 128 as target format if nothing else is specified?
[21:20:45 CET] <c_14> Either use -c copy (the cuts won't be as precise) or set an audio bitrate. There is no "use the same bitrate" option
[21:20:55 CET] <furq> or use mp3splt
[21:33:42 CET] <shevy> ok
[21:49:23 CET] <klaxa> ><c_14> Either use -c copy (the cuts won't be as precise) or set an audio bitrate. There is no "use the same bitrate" option
[21:49:28 CET] <klaxa> not precise for mp3?
[21:50:04 CET] <klaxa> for mp3 cutting at frames should be precise enough, no?
[21:50:12 CET] <DHE> if you didn't specify -c copy then ffmpeg will transcode the audio
[21:50:15 CET] <fritsch> klaxa: no
[21:50:33 CET] <fritsch> cause of the reservoir there exists information in preceeding and following frame
[21:50:38 CET] <klaxa> no? how many samples in a frame?
[21:50:57 CET] <klaxa> ok
[21:51:05 CET] <DHE> fractions of a second
[21:52:49 CET] <klaxa> yeah, that's what i thought, i guess it depends on what you define as "precise"
[21:54:37 CET] <DHE> someone somewhere will try to get an audio cut at 0.01 second precision and complain when it isn't working and suddenly skips ahead 0.1 seconds
[21:54:47 CET] <DHE> (I don't know what the exact numbers are, I just made the above up on the spot)
[22:19:00 CET] <shevy> 0.01 is totally fine for me :)
[22:19:28 CET] <shevy> now if the .mp3 is 100 seconds, and I want to chop off the leading 5 seconds... and instead I'd end up with 30 seconds chopped up, then I'd worry!
[22:37:26 CET] <shevy> it worked fine, thanks, laters!
[00:00:00 CET] --- Fri Dec 11 2015


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