[Ffmpeg-devel-irc] ffmpeg.log.20160406

burek burek021 at gmail.com
Thu Apr 7 02:05:01 CEST 2016


[00:23:50 CEST] <rjp421> petecouture, do u have a ustream token?
[00:29:00 CEST] <rjp421> hmmm nvm i thought they accepted hls input
[00:52:41 CEST] <petecouture> rjp421 no I don't. Thanks for trying.
[01:32:16 CEST] <t4nk536> Hello, I'm working on a free educational project, I was auditioning with ffmpeg for conversion of videos in Windows, the settings are very conplicadas, someone could support me?
[01:36:39 CEST] <t4nk574> hello
[01:38:18 CEST] <leonardo_> hello
[01:38:57 CEST] <leonardo_> Do you speak in spanich?
[01:39:49 CEST] <leonardo_> hello iive
[01:40:13 CEST] <leonardo_> wath do you do?
[02:41:58 CEST] <DolpheenDream> howdy
[02:42:52 CEST] <DolpheenDream> anyone has any idea whether it is necessary to have the HD tag set in the mp4 file ? e.g. to play on ATV for instance ? what does the presence of this HD tag really do, if the movie is a HD (1080p) anyway ?
[02:48:47 CEST] <relaxed> what is ATV and do you have a file with this tag set?
[02:49:14 CEST] <DolpheenDream> hehe :) atv = appleTV
[02:49:46 CEST] <DolpheenDream> files purchased from iTunes store have HD set (if HD version was purchased) and it shows in ATV as HD label..
[02:51:06 CEST] <relaxed> pastebin.com the output of "ffmpeg -i file" on one of these files
[02:53:10 CEST] <relaxed> it's probably just metadata you can replicate with ffmpeg
[03:10:53 CEST] <john_doe_jr> I'm having a delay in my streaming using rtp protocol and was wondering if I should use rtsp&would that be better?
[03:11:03 CEST] <john_doe_jr> I found this link: https://ffmpeg.org/ffmpeg-protocols.html#rtsp
[03:17:07 CEST] <yeoj> if i know the coordinates of a moving object in a video, is there some way i can pass the coordinates to an ffmpeg blur filter in a stream and only blur the moving object and coordinates i'm looking for in a video?
[03:24:19 CEST] <yeoj> nevermind, looks like i wasn't searching for the right thing.. http://zulko.github.io/moviepy/cookbook/blurred_face.html seems promising
[03:24:38 CEST] <furq> john_doe_jr: afaik you need an external server for rtsp
[03:27:38 CEST] <john_doe_jr> furq: what is the fastest possible stream w/ ffmpeg&do u know?
[03:28:50 CEST] <furq> i've no idea for just audio
[03:29:52 CEST] <furq> you probably want to check your player's buffer settings
[03:31:24 CEST] <john_doe_jr> furq: alright&it's vlc
[03:32:32 CEST] <john_doe_jr> furq: I found the "http://ffmpeg-users.933282.n4.nabble.com/async-td935787.html" option @ http://lzone.de/cheat-sheet/ffmpeg just for audio
[05:15:01 CEST] <kurtCobain> When I used AVFoundation to record the desktop and produce segments of .webm videos, portions of the videos are sped up during playback. http://pastebin.com/m1AKJTGD
[05:17:35 CEST] <relaxed> kurtCobain: I'm pretty sure that should be -framerate 24
[05:18:34 CEST] <relaxed> ffmpeg -h muxer=avfoundation
[05:18:43 CEST] <relaxed> er, ffmpeg -h demuxer=avfoundation
[05:33:43 CEST] <kurtcobain_> Seems like -r -> -framerate made a difference. Monitoring the console output the framerate was more consistently at or close to 24 fps and the speed was right around 1x.
[06:19:01 CEST] <aletorrado> Hi!!!! I'm using latest FFMPEG 3.0 and trying to do adaptive live streaming with the recent DASH MUXER, but don't know how to specify multiple conversions. I'm currently doing this: ffmpeg -v verbose -i rtsp://stream.eltrecetv.com.ar/live13/13tv/13tv1 -c:v copy -c:a copy -f dash output.mpd
[06:19:55 CEST] <aletorrado> A 720p & 480p output example would be VERY appreciated :) :)
[06:21:32 CEST] <relaxed> aletorrado: http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash
[06:21:52 CEST] <aletorrado> Nope! I want to use libx264!
[06:22:18 CEST] <aletorrado> Cannot use webm_dash_manifest
[06:23:30 CEST] <relaxed> maybe http://stackoverflow.com/questions/28429526/ffmpeg-h-264-encoding-for-html5-and-ultimately-mpeg-dash
[06:23:45 CEST] <relaxed> google should provide some examples
[06:24:57 CEST] <aletorrado> I've already read that
[06:25:22 CEST] <aletorrado> He doesn't do adaptive
[06:26:53 CEST] <thebombzen> aletorrado: if you mean you want to take the input stream and encode two versions of the output stream, you can specify -map twice. that is, if you use -map 0:v -map 0:v then you get two streams
[06:27:01 CEST] <thebombzen> you can scale them individually with -filter_complex
[06:28:50 CEST] <thebombzen> another thing you could try is this: -filter_complex '[0:v] scale=1280:720 [v1] ; [0:v] scale=854:480 [v2]' -map '[v1]' -map '[v2]'
[06:29:01 CEST] <aletorrado> that is! Thanks @thebombzen !
[06:29:38 CEST] <thebombzen> for more info on how to do weird stuff, I'd read the filtering guide. FFmpeg's filtering is extremely powerful and flexible
[06:29:58 CEST] <thebombzen> careful that you also have to map the audio
[06:30:40 CEST] <thebombzen> once you have two video streams, you can select them with "stream specifiers" i.e. you could set the codec for both with -c:v libx264
[06:31:13 CEST] <thebombzen> if you want the codec for the first to be different you could use -c:0 libx264 -c:1 mpeg4 hypothetically
[06:31:18 CEST] <aletorrado> yeap I've just tested and added audio :)
[06:31:22 CEST] <thebombzen> cool :D
[06:41:33 CEST] <aletorrado> thanks a lot @thebombzen
[09:57:58 CEST] <andrey_utkin> is it legal to stitch into MP4 container two x264 videos, in which the second part has customly decreased i_keyint_max? The extradata is taken from first clip (with "longer" i_keyint_max, apparently default one, which seems to be ~250 frames)
[10:00:00 CEST] Last message repeated 1 time(s).
[10:10:19 CEST] <zamba> hi! i'm trying to convert some video from vhs to digital format.. i'm using a simple command like: ffmpeg -f video4linux2 -i /dev/video0 -f alsa -i default output.mkv
[10:10:46 CEST] <zamba> when looking at the CR line output i see that fps is currently at 22
[10:10:49 CEST] <zamba> why not 24 or 25?
[10:10:57 CEST] <zamba> speed is also at 0.999x
[10:12:13 CEST] <zamba> this is the input: Input #0, video4linux2,v4l2, from '/dev/video0': Duration: N/A, start: 10449717.744269, bitrate: 165888 kb/s | Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 720x576, 165888 kb/s, 25 fps, 25 tbr, 1000k tbn, 1000k tbc
[10:12:27 CEST] <zamba> so the input is 25 fps, but the output shows:
[10:12:38 CEST] <zamba> frame=58963 fps= 22 q=28.0 size= 1062851kB time=00:43:52.92 bitrate=3306.9kbits/s dup=0 drop=91 speed=0.999x
[10:12:47 CEST] <zamba> do i have anything to worry about here?
[10:16:57 CEST] <relaxed> zamba: fps= 22 is how fast it's encoding, not the output framerate
[10:18:24 CEST] <relaxed> drop=91 is maybe something to worry about
[10:18:48 CEST] <zamba> relaxed: i got that pretty early in the capture
[10:18:56 CEST] <zamba> relaxed: and it's been stable at 91 for a long time now
[10:19:26 CEST] <relaxed> what's your command?
[10:19:41 CEST] <zamba> see above: ffmpeg -f video4linux2 -i /dev/video0 -f alsa -i default output.mkv
[10:19:42 CEST] <relaxed> oh, nevermind
[10:20:15 CEST] <relaxed> add -framerate 25 before -i /dev/...
[10:20:22 CEST] <zamba> what does that do?
[10:20:31 CEST] <relaxed> er, it assumes that
[10:21:17 CEST] <zamba> hm?
[10:22:02 CEST] <relaxed> the default input framerate for -f video4linux2 is 25 fps, which is the same for PAL
[10:23:33 CEST] <zamba> do i need to add -framerate 25, then?
[10:23:46 CEST] <relaxed> You do not
[10:24:52 CEST] <relaxed> zamba: how does the video look?
[10:25:06 CEST] <zamba> relaxed: it looks ok, but it's a bit.. eh.. laggy here and there
[10:26:25 CEST] <zamba> dunno how better to describe it :)
[10:30:51 CEST] <relaxed> zamba: have a look at "ffmpeg -h demuxer=video4linux2" and https://trac.ffmpeg.org/wiki/Capture/Webcam
[10:32:36 CEST] <zamba> oh.. but i have no idea what to get from this :)
[10:49:08 CEST] <zamba> and the output of ffmpeg is filled with errors like "Past duration 0.xxxxxx too large"
[10:49:18 CEST] <zamba> that i have no idea how to interpret
[12:21:20 CEST] <ingolfur> I just installed ffmpeg on Ubuntu 14.04. When I run ffmpeg -version I get the following: ffmpeg version N-79139-gde1a0d4 Copyright (c) 2000-2016 the FFmpeg developers. built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.1)
[12:21:30 CEST] <ingolfur> does anyone know what version that is of ffmpeg?
[12:24:59 CEST] <relaxed> git from 2016-03-26
[12:28:30 CEST] <ingolfur> Thanks!
[12:54:39 CEST] <momomo> momomo
[14:14:38 CEST] <brm> dead channel
[14:17:15 CEST] <DHE> Umm, wrong. besides it's only just morning in north america.
[14:50:53 CEST] <ghiciro> hello
[14:51:36 CEST] <ghiciro> i`m trying to re encode just audio from e-ac3 to mp2 audio from a ts to a ts, video is copied without transcoding, and from time to time i get some : exponent out-of-range , error decoding the audio block and you can hear the audio glitch at that time
[16:38:02 CEST] <PowerOn> Good morning all
[16:39:35 CEST] <PowerOn> Can I make a question? Ive compiled ffmeg on ubuntu 14.04 and now I have ~/ffmpeg_build ~/ffmpeg_sources ~/bin/
[16:39:47 CEST] <PowerOn> Is there any way to move those folders from home, to another place?
[16:39:53 CEST] <PowerOn> without losing everything?
[16:41:14 CEST] <PowerOn> sorry for bothering you folks :)
[16:57:57 CEST] <zamba> relaxed: yeah, i'm able to reproduce it.. in that sense that i'm able to see that playing back the same part of the tape several times reveal the image lag at different positions
[16:58:14 CEST] <zamba> relaxed: so there's probably something with I/O or the encoding process
[16:59:29 CEST] <DHE> PowerOn: the binaries ffmpeg and ffprobe are usually all you need. copy them into /usr/local/bin or something like that
[16:59:52 CEST] <DHE> if they're really big (ie. 15 megabytes or more) then there should be no further dependencies that were built with them
[17:08:40 CEST] <PowerOn> Hi DHE!
[17:09:15 CEST] <PowerOn> So, If I move the 3 folders into /usr/local/bin should work?
[17:09:34 CEST] <furq> no
[17:09:41 CEST] <furq> move the contents of ~/bin to /usr/local/bin
[17:10:03 CEST] <PowerOn> and what about the other folders? Can I remove them?
[17:10:24 CEST] <furq> if you don't want to compile ffmpeg again then sure
[17:11:18 CEST] <PowerOn> Thanks furq!
[17:11:27 CEST] <PowerOn> I'll take that shoot
[17:20:06 CEST] <Nosomy> which video format is super fast to encode?, mpeg1, mpeg2 or xvid?
[17:20:51 CEST] <Mavrik> mjpeg.
[17:21:35 CEST] <Nosomy> mjpeg have a high bitrate
[17:22:29 CEST] <TD-Linux> the others you listed aren't exactly winners either
[17:22:36 CEST] <Nosomy> another alternative ?
[17:22:43 CEST] <Mavrik> H.264 with hardware encoder :P
[17:23:00 CEST] <TD-Linux> or even with a software one.
[17:23:02 CEST] <Mavrik> You said nothing about the details of your usecase.
[17:23:13 CEST] <Mavrik> So whatever, raw video? :P
[17:23:17 CEST] <Nosomy> quality is no required
[17:23:31 CEST] <TD-Linux> so use mjpeg with a lower quality setting?
[17:24:16 CEST] <Nosomy> mjpeg in lower quality setting is high bitrate yet.
[17:24:30 CEST] <Nosomy> but,thanks for tip
[17:24:34 CEST] <furq> you didn't say anything about bitrate
[17:39:10 CEST] <kepstin> x264 with the correct options can be very fast to encode, and unlike most mpeg1/2/4 encoders it can do multithreaded too
[17:39:16 CEST] <furq> he already left
[17:39:32 CEST] <kepstin> ...
[17:39:35 CEST] <kepstin> ok then
[18:06:46 CEST] <PowerOn> what's the diff between ffmpeg-snapshot.tar.bz2 and ffmpeg-3.0.tar.xz?
[18:06:52 CEST] <PowerOn> which is the latest?
[18:06:55 CEST] <c_14> snapshot
[18:06:57 CEST] <c_14> It's from git.
[18:07:05 CEST] <c_14> Whereas 3.0 is the release branch
[18:07:15 CEST] <PowerOn> thanks C
[18:35:25 CEST] <zamba> i'm trying to capture audio from my line in jack.. i've killed pulseaudio.. and i'm trying to do "-f alsa -i default"
[18:35:38 CEST] <zamba> but it looks like ffmpeg wants to use pulseaudio still?
[18:35:40 CEST] <zamba> ALSA lib pulse.c:243:(pulse_connect) PulseAudio: Unable to connect: Connection refused
[18:35:56 CEST] <c_14> zamba: you still have pulse configs lying around in your alsa directories
[18:36:14 CEST] <zamba> c_14: what's an alsa directory?
[18:36:44 CEST] <c_14> the config directories for alsa. /usr/share/alsa iirc
[18:36:45 CEST] <zamba> or rather, where are they?
[18:37:09 CEST] <zamba> ah
[18:47:57 CEST] <dailyuser> Hi all, I am trying to cross fade 2 videos segments using the http://superuser.com/questions/778762/crossfade-between-2-videos-using-ffmpeg but the resolution I am trying to get is 1280x720.
[18:48:11 CEST] <dailyuser> The output is always 960x720 instead
[18:48:39 CEST] <dailyuser> Yes, I did change the command to be 1280x720
[18:49:03 CEST] <c_14> get rid of the scale filter
[18:50:38 CEST] <dailyuser> Thanks will try that. Also, is there a way to make it faster.. Currently, it takes around 30 seconds to cross fade 2 videos 10 seconds each
[18:51:16 CEST] <dailyuser> The only thing that I want to do is add cross fade between 2 videos
[19:04:59 CEST] <zamba> i switched hardware, and then the encoding goes smooth.. it's dead solid on 25 fps.. and the video is smooth as well when played back.. even though the first hardware i tried it on should be way better
[19:05:33 CEST] <zamba> it's also not using that much cpu as it did on the newer hardware - where it consumed all four cores.. now it's just humming along..
[19:05:47 CEST] <zamba> exactly the same command
[20:07:34 CEST] <dailyuser> ffmpeg -i 1.mp4 -i 2.mp4 -f lavfi -i color=black -filter_complex \ "[0:v]format=pix_fmts=yuva420p,fade=t=out:st=4:d=1:alpha=1,setpts=PTS-STARTPTS[va0];\ [1:v]format=pix_fmts=yuva420p,fade=t=in:st=0:d=1:alpha=1,setpts=PTS-STARTPTS+4/TB[va1];\ [2:v]scale=1280x720,trim=duration=9[over];\ [over][va0]overlay[over1];\ [over1][va1]overlay=format=yuv420[outv]" \ -vcodec libx264 -map [outv] out.mp4 always ends up giving me a 960x720 video
[20:08:48 CEST] <dailyuser> Can some one please help me try to figure why I keep getting a 960x720 even when specifying 1280x720 there?
[20:26:39 CEST] <Polochon_street> Hi! I'm using the ffmpeg lib in C, and want to turn off debug info (like [mp3 @ 0x556caf8327c0] Estimating duration from bitrate, this may be inaccurate), is there any easy way to do it?
[20:28:27 CEST] <Polochon_street> there's a « log_level_offset » in AVCodecContext, but I can't figure out what it's related to
[20:28:39 CEST] <fritsch> Polochon_street: https://ffmpeg.org/doxygen/2.5/group__lavu__log.html#ga14034761faf581a8b9ed6ef19b313708
[20:29:03 CEST] <Polochon_street> fritsch: thanks very much!
[20:29:14 CEST] <fritsch> take care to the threadsafety
[20:30:29 CEST] <fritsch> you can have a look in kodi's FFmpeg.cpp
[20:30:42 CEST] <fritsch> which implements a logger with that signature
[20:31:15 CEST] <Polochon_street> well I'm just using av_log_set_level, thanks very much :)
[20:31:27 CEST] <fritsch> hehe
[20:31:32 CEST] <fritsch> to not log anything
[20:31:34 CEST] <fritsch> hehe
[20:32:50 CEST] <ffmpeg-user> Hi, sorry to repost again but I am trying to add cross fading between 2 videos of 1280x720p using the instructions mentioned here http://superuser.com/questions/778762/crossfade-between-2-videos-using-ffmpeg
[20:33:12 CEST] <ffmpeg-user> The output is always 960x720 even when I change the scale on it
[20:33:26 CEST] <ffmpeg-user> If I remove the scale the output is of 960x720
[20:33:36 CEST] <ffmpeg-user> I mean 360x420
[21:08:55 CEST] <Amitari> I just found out that lossless H264 isn't lossless at all. Does anyone know how to modify the commands "ffmpeg -framerate 50 -pattern_type glob -i '*.png' -q:v 0 out.mkv" so that it outputs any form of lossless video?
[21:09:27 CEST] <pzich> you almost certainly don't want lossless
[21:09:38 CEST] <pzich> you can try -crf 0, but make sure you have a lot of disk space...
[21:11:37 CEST] <Amitari> I'll try!
[21:12:15 CEST] <furq> Amitari: what makes you think it isn't lossless
[21:12:34 CEST] <furq> i guess from the fact you're converting png that it's doing a colourspace conversion
[21:12:53 CEST] <pzich> yeah
[21:12:59 CEST] <furq> you could try -pix_fmt yuv444p
[21:13:10 CEST] <pzich> if you really want lossless you could export to raw BGRA, but be prepared for a big file :D
[21:13:12 CEST] <furq> but if you need to keep it rgb then there are other lossless codecs which support that
[21:13:13 CEST] <Amitari> I extracted the images from a video that was pixelart, and it had some sorta PNG-based video codec. All the colours were completely solid.
[21:13:22 CEST] <Amitari> After reassembling these in a video, it wasn't..
[21:13:37 CEST] <furq> yeah it'll probably default to yuv420p which has 1/4 chroma resolution
[21:13:43 CEST] <pzich> solid as in not blurry, or richer colors?
[21:14:04 CEST] <furq> oh
[21:14:08 CEST] <furq> apparently x264 does support rgb
[21:14:14 CEST] <pzich> hmm, in my experience it hasn't defaulted to yuv420p and I've had to specify it if I want qt-compatible files
[21:14:28 CEST] <furq> Amitari: use -pix_fmt yuv444p or -pix_fmt rgb24
[21:14:43 CEST] <pzich> depending on what player you're playing it back in
[21:14:58 CEST] <Amitari> pzich: The colours had a bunch of artifacts in them.
[21:15:02 CEST] <fritsch> will get funny 50 fps
[21:15:07 CEST] <fritsch> + rgb24
[21:15:12 CEST] <fritsch> as this will be software accelerated
[21:15:25 CEST] <furq> well lossless x264 is already shitty for playback
[21:15:35 CEST] <Amitari> Hey, this is just to archive stuff losslessly.
[21:15:46 CEST] <furq> also for reference you should use -q:v 0, not -crf 0
[21:15:46 CEST] <fritsch> png's are good for archiving
[21:15:55 CEST] <furq> -crf 0 is only the same with 8-bit x264
[21:16:03 CEST] <Amitari> Yeah, but I want it in a video format.
[21:16:11 CEST] <fritsch> he used -q:v 0 initially
[21:16:22 CEST] <furq> i know
[21:16:23 CEST] <Amitari> This is mainly to archive the stuff, either for uploading to YouTube, or to encode to lossy formats later.
[21:16:30 CEST] <furq> 20:09:38 ( pzich) you can try -crf 0, but make sure you have a lot of disk space...
[21:16:38 CEST] <fritsch> jep
[21:16:40 CEST] <furq> i was responding to that
[21:17:16 CEST] <Amitari> Alright, I'll try that pix_fmt thing.
[21:18:02 CEST] <furq> iirc there will be some slight loss by converting from rgb to yuv444p
[21:18:29 CEST] <furq> nowhere near as bad as with 4:2:0 though
[21:19:02 CEST] <furq> there is also no point keeping it rgb if you're going to be converting it to a yuv-based format later
[21:19:35 CEST] <Amitari> But I want to have it archived in a lossless format!
[21:19:45 CEST] <fritsch> then keep the pngs
[21:19:49 CEST] <fritsch> don't use h264
[21:19:54 CEST] <furq> keep the pngs or use -pix_fmt rgb23
[21:19:59 CEST] <furq> s/3/4/
[21:20:13 CEST] <Amitari> I tried that, but it said "Incompatible pixel format 'rgb24' for codec 'libx264', auto-selecting format 'yuv444p'".
[21:20:17 CEST] <furq> oh
[21:20:19 CEST] <Amitari> And that format gave a lossy result.
[21:21:26 CEST] <fritsch> it's h264 after all ... try mjpeg (yeah jpeg sucks) but that way you get a lot "keyframes"
[21:21:50 CEST] <fritsch> mjpeg with highest quality
[21:21:59 CEST] <Amitari> Will that be lossless JPG?
[21:22:01 CEST] <fritsch> no
[21:22:04 CEST] <fritsch> 100% not
[21:22:08 CEST] <fritsch> all those formats are not lossless
[21:22:09 CEST] <Amitari> Oh...
[21:22:24 CEST] <Amitari> Well, I know there's a way to save JPG pictures losslessly as long as they don't use transparency and stuff.
[21:22:43 CEST] <fritsch> try
[21:22:49 CEST] <furq> i'm not sure if ffmpeg has any lossless codecs with rgb support
[21:22:58 CEST] <furq> i think ffv1 is yuv-only
[21:23:16 CEST] <Amitari> This doesn't really have anything to do with colours at all, the pixel-art video got artifacts when I tried.
[21:23:20 CEST] <kepstin> I thought recent versions of x264 you could actually do a lossless rgb encoding.
[21:23:32 CEST] <furq> yeah i read that but he says it doesn't work
[21:23:35 CEST] <furq> maybe it's an old ffmpeg
[21:23:48 CEST] <kepstin> jpeg does conversion to yuv and chroma subsampling in most modes
[21:23:54 CEST] <Amitari> ffmpeg 1:3.0.1-1
[21:23:57 CEST] <kepstin> so it's not gonna be lossless
[21:24:13 CEST] <furq> not an old ffmpeg then
[21:24:32 CEST] <furq> also i think i'm wrong about ffv1
[21:24:43 CEST] <furq> Amitari: try -c:v ffv1 -pix_fmt rgb24
[21:24:54 CEST] <Amitari> Sure, lemme try...
[21:25:38 CEST] <kepstin> ah, in ffmpeg, the rgb mode of x264 has a different name
[21:25:44 CEST] <kepstin> try -c:v libx264rgb
[21:25:49 CEST] <furq> oh how convenient
[21:25:51 CEST] <Amitari> Hmm, now it actually looks like it's lossless in VLC at least, lemme try extracting the pics now.
[21:25:52 CEST] <kepstin> with -q:v 0 it'll be lossless
[21:26:44 CEST] <Amitari> It wasn't when I tried.
[21:26:49 CEST] <furq> 20:25:44 ( kepstin) try -c:v libx264rgb
[21:26:50 CEST] <furq> ^
[21:27:08 CEST] <Amitari> "-c:v ffv1 -pix_fmt rgb24" made it completely lossless. :P
[21:27:10 CEST] <Amitari> :D
[21:27:26 CEST] <kepstin> but yeah, ffv1 would be a good choice for this as well
[21:27:45 CEST] <Amitari> Sure, but isn't the option that worked first the most simple one?
[21:27:53 CEST] <Amitari> I only encode really short videos in lossless, so...
[21:28:24 CEST] <Amitari> The thing that takes up most space is all the frames I'm extracting.
[21:29:23 CEST] <Amitari> I set VLC to extract all frames, and then I stop it when I know it has extracted the ones I want.
[21:29:43 CEST] <furq> you know you could just do that with ffmpeg
[21:29:58 CEST] <Amitari> Yeah, but I can't know what exact frame I'm on.
[21:30:25 CEST] <Amitari> Then I delete all the ones I don't want, and then I open the audio in Audacity and calculate exactly what part of the audio I should use. Then I save that in FLAC, which I mux together with the video track after that has been reassembled.
[21:49:47 CEST] <petecouture> Could someone explain this flag a little more then what's in the 264 spec
[21:49:49 CEST] <petecouture> sc_threshold
[21:49:59 CEST] <petecouture> sc_threshold:  Adjusts the sensitivity of x264's scenecut detection. Rarely needs to be adjusted. Recommended default: 40
[21:50:37 CEST] <furq> it's how much of the frame needs to change for x264 to insert an IDR frame
[21:50:38 CEST] <petecouture> I'm working to create multibit rate encoding and it's recommended to set that to -
[21:50:50 CEST] <petecouture> set it to 0 rather
[21:51:07 CEST] <petecouture> furq: Do you mean pixel bitmap data?
[21:51:09 CEST] <furq> the only reason to set that to 0 is for fixed-size gops
[21:51:20 CEST] <furq> i don't know exactly how it calculates it
[21:51:30 CEST] <petecouture> AHHH perfect thank you
[21:51:35 CEST] <furq> "x264 calculates a metric for every frame to estimate how different it is from the previous frame. If the value is lower than scenecut, an IDR frame is used."
[21:51:39 CEST] <petecouture> I do need a fixed size gop
[21:51:53 CEST] <furq> you can use keyint_min instead
[21:52:02 CEST] <petecouture> I am
[21:52:09 CEST] <furq> you only need one or the other
[21:52:13 CEST] <petecouture> The whitepaper I'm reading on it has both
[21:52:21 CEST] <furq> afaik scenecut won't override keyint_min
[22:02:15 CEST] <petecouture> furq: Thank you for the information. I think by setting it to 0 it shuts off that detection algorthym which will be good.  -r 24 -g 48 -keyint_min 48 -sc_threshold 0
[22:02:48 CEST] <petecouture> If you use that configureation above you always get perfect keyframe alignment between multiple bitrates
[22:12:20 CEST] <furq> you don't need keyint_min if scenecut is disabled
[22:12:38 CEST] <furq> the reverse might be true but it might still cause a slowdown, i'm not familiar enough with the code
[22:23:04 CEST] <aletorrado> Hi!! I'm dealing with the new DASH MUXER in FFMPEG 3.0 for adaptive streaming. I've noticed the muxer is not saving the BANDWIDTH VALUE for the VIDEO STREAMS in the MANIFEST. This breaks the automatic adaptive switch on every DASH player.
[22:23:45 CEST] <aletorrado> This is the command I'm using to test, pretty simple: ffmpeg -v verbose -i rtsp://stream.eltrecetv.com.ar/live13/13tv/13tv1 -filter_complex '[0:v:0] scale=128:72 [v0] ; [0:v:0] scale=256:144 [v1]' -map '[v1]' -map '[v0]' -map 0:a -f dash output.mpd
[22:24:55 CEST] <JEEB> https://github.com/FFmpeg/FFmpeg/blob/master/libavformat/dashenc.c#L601
[22:25:12 CEST] <JEEB> as far as I can tell by the code, it does set either the bit rate or the VBV maxrate value in there
[22:25:41 CEST] <JEEB> so if one of those is set by your video encoder, you are going to get the bandwidth thing there
[22:25:44 CEST] <furq> does it set the bitrate if -b:v hasn't been set
[22:26:08 CEST] <JEEB> if the encoder has a default bit rate I think it might default to whatever libavcodec defaults to for that format
[22:26:24 CEST] <JEEB> but it doesn't have to be b:v, it can also be maxrate:v
[22:33:07 CEST] <aletorrado> Awesome. You're my heroes!
[22:39:14 CEST] <petecouture> in a h264 stream, there's no preference between having the audio or video stream coming first is there?
[22:39:40 CEST] <furq> do you want to reconsider that third word
[22:40:26 CEST] <petecouture> encoding
[22:40:35 CEST] <petecouture> m3u8 stream
[22:41:08 CEST] <bergeron37> I'm using avfoundation to record the user's desktop and the segment muxer to spit out recording files every 10 seconds or so. Is there an accurate way for me to obtain the timestamp at which the recording files video was taken?
[22:41:41 CEST] <petecouture> bergeron37, the timestamp the files were created at or the timestamp of the playback?
[22:41:59 CEST] <furq> petecouture: it shouldn't make a difference with mpegts, but some players might expect video first
[22:42:00 CEST] <bergeron37> @petecouture recorded at
[22:42:38 CEST] <petecouture> bergeron37: With ffmpeg 3.0+ I would recommend using the HLS muxer instead of segment. I just converted mine over. You can save the files using the actual ts
[22:43:02 CEST] <petecouture> Also if you have ffmpeg within an application you should get status information as the stream is processing which contains the current encoding ts
[22:43:33 CEST] <petecouture> From the client side if you playing it as a stream, you should have meta data events thrown during playback that will contain the current ts of the video
[22:44:17 CEST] <petecouture> furq: Thank you I think VLC may. I'm having issues loading this m3u8 with vlc. Plays fine with everything else.
[22:45:49 CEST] <petecouture> bergeron37: Here's how my output script has changed from segment to hls http://pastebin.com/PtrL0i1J
[22:46:13 CEST] <furq> bergeron37: -f ssegment -srtftime 1 output_%H%M%S.ts
[22:46:22 CEST] <furq> s/srtf/strf/
[22:46:44 CEST] <petecouture> furq: That command didn't work for me on ffmpeg 2.7 dunno if it was a bug but it's why I updated to 3
[22:47:56 CEST] <bergeron37> @furq do you know how accurate that timestamp is?
[22:49:03 CEST] <bergeron37> I'm trying to figure out if I can use it to identify the time of the recording accurately
[22:50:21 CEST] <petecouture> sycronized broadcasts?
[22:55:04 CEST] <bergeron37> Specifically, do you know if there is any way to get it within milliseconds
[23:14:29 CEST] <petecouture> Woot I finally got perfect 10 second ts segments from a live feed!
[23:14:58 CEST] <petecouture> ffmpeg has the learning curve of Eve online. You think it's easy at first glance but then you start reading the details of the documetnation....
[23:54:55 CEST] <Tiago_> Hello guys. Was the CRYPTO_LOCK Deprecated?
[00:00:00 CEST] --- Thu Apr  7 2016


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