[Ffmpeg-devel-irc] ffmpeg.log.20191130

Sun Dec 1 03:05:01 EET 2019

[00:59:01 CET] <sector_surfer> Hi.
[00:59:25 CET] <sector_surfer> What commandline can I use to slow down the download rate of a stream when downloading form an url?
[01:00:13 CET] <sector_surfer> for example, I want to limit the download rate of ffmpeg to say 15 k, because I've got other programs who's download is more importantthat are
[01:00:31 CET] <sector_surfer> whoops
[01:01:22 CET] <sector_surfer> whenever I download from a facebook livestream via .mpd, there are parts of the video that repeat itself
[01:03:38 CET] <sector_surfer> https://video.fmel5-1.fna.fbcdn.net/hvideo-prn1-ftw/_nc_cat-103/v/rVU7tYWnFTg5RotieVCsS/live-dash/dash-abr5/2610964682526581.mpd?_nc_rl=AfC57qlp5wJv8TZb&oh=5113a41a61ec6fdcb7b0e3b7705ab511&oe=5DE3B053
[01:09:54 CET] <DHE> I suggest something like: curl http://<your-url> --limit-rate=15k | ffmpeg -i - [...]
[01:15:17 CET] <sector_surfer> I'm using windows, not linux
[01:20:00 CET] <LevelDrain> hello
[01:20:14 CET] <LevelDrain> i have a better way for add list of musics to a video?
[01:21:31 CET] <b1rk0ff> is there a filter to filter out parts of an audio stream that are below certain 'decibels' or sound level ?
[01:26:13 CET] <kepstin> b1rk0ff: https://ffmpeg.org/ffmpeg-filters.html#agate
[01:26:25 CET] <kepstin> hmm, well, that might not be what you want actually
[01:26:41 CET] <kepstin> that just allows you to completely mute sections below a certain sound level
[01:27:28 CET] <kepstin> b1rk0ff: maybe https://ffmpeg.org/ffmpeg-filters.html#silenceremove
[01:28:04 CET] <b1rk0ff> I want to actually remove/not reencode low sound level sections
[01:28:56 CET] <b1rk0ff> silencremove is only for silence on the beginning/end
[01:43:14 CET] <LevelDrain> The only way I can find is to concatenate all the music in a single music file, and then put the music together with the video. Isn't there a way to do it all in one step?
[01:44:21 CET] <kepstin> b1rk0ff: might i suggest re-reading the silenceremove docs :)
[06:17:20 CET] <void09> how would I extract dvdsub subtitles from an mkv file ?
[06:17:45 CET] <void09> ffmpeg -i "input.mkv"  -map 0:s:0 -c copy subtitle_file.vob.sub
[06:17:57 CET] <void09> [microdvd @ 0x5606cee3e180] Exactly one MicroDVD stream is needed.
[06:17:58 CET] <void09> Could not write header for output file #0 (incorrect codec parameters ?): Operation not permitted
[06:26:55 CET] <furq> there is no vobsub muxer
[06:26:59 CET] <furq> mkvextract will do it iirc
[06:30:05 CET] <furq> void09: mkvextract foo.mkv tracks 2:bar.idx
[06:30:14 CET] <furq> or whatever the track id from mkvmerge --identify is
[06:33:13 CET] <void09> got it :)
[06:33:17 CET] <void09> writing everything down
[06:33:28 CET] <void09> is there no cheatsheet with all this stuff in one place
[06:33:30 CET] <void09> everything to everything
[06:33:47 CET] <furq> that'd be more than one sheet
[06:33:48 CET] <nicolas17> there's like 300 formats
[06:34:05 CET] <void09> well, then a smart sheet, input type, output type, object type
[06:34:21 CET] <void09> DVD SUBS TO .VOB/.SUB
[06:34:21 CET] <void09> mencoder VTS_01_0.IFO -nosound -ovc frameno -o /dev/null -vobsuboutindex 0 -sid 0 -vobsubout subEN.vob
[06:34:37 CET] <void09> see, i write everything down as I find it. sometimes the answers are not easy to find in the first google result page
[06:34:47 CET] <void09> well, they usually have windows programs as answers
[06:35:10 CET] <furq> is mencoder still developed
[06:35:57 CET] <void09> probably not, but this is what i found and works
[06:36:15 CET] <furq> saying that i'd probably use tcdemux for that and that definitely isn't developed any more
[06:36:56 CET] <void09> I'll have to wind a near fool proof way of converting .vob/sub to .srt oen day
[06:37:08 CET] <furq> there's no good non-ocr way of doing it
[06:37:21 CET] <void09> ocr is the only way, what do you mean
[06:37:31 CET] <furq> even the ocr methods aren't great
[06:37:39 CET] <void09> what non-ocr methods are there?
[06:38:01 CET] <void09> I find it pretty amazing what AI can do these days, and still there's no good way of turning dvd subs to text ? lol
[06:38:37 CET] <furq> i meant no good non-gui method of doing it
[06:38:51 CET] <furq> the cli stuff i know of uses tesseract but it has some kind of database of common fonts
[06:38:59 CET] <furq> which is still technically ocr, just less tedious
[06:39:01 CET] <void09> right, and why does that not work well ?
[06:39:20 CET] <nicolas17> dvd subs have crappy resolution, for a start
[06:39:45 CET] <void09> well those can be upscaled easily i think
[06:40:16 CET] <furq> honestly i normally just leave them as image subtitles now
[06:40:40 CET] <furq> l'll
[06:40:52 CET] <furq> sorry i mean l,ll
[06:44:02 CET] <void09> yeah I leave them as images too, until i find a good way to convert
[09:21:09 CET] <funnybunny2> Is there a table which shows which audio encodings support planar, interleaved, or both sample formats?
[12:16:36 CET] <Arnob> Hi, could someone tell me what I'm doing wrong here. When using the following command to generate a waveform and blend it with a pic, if I input a mp3 as audio it works fine but if I input a WAV file I've got errors.
[12:16:50 CET] <Arnob> The command I use: ffmpeg -y -i 12.WAV -loop 1 -i b.jpg -filter_complex "[0:a]showwaves=s=1280x720:mode=line,colorkey=0x000000:0.01:0.1,format=yuva420p[v];[1:v][v]overlay[outv]" -map "[outv]" -pix_fmt yuv420p -map 0:a -c:v libx264 -c:a copy -shortest output1.mp4
[12:18:48 CET] <Arnob> the errors I receive when using a wav : https://arnauld.org/zerobin/?ee89459bd8bd6f9e#qGDPJmgMLRQlpzBAWcrzO0f/uZd90KIpGRt/0oHbbCA=
[12:20:00 CET] <c_14> can't copy wav into mp4
[12:20:04 CET] <c_14> reencode the audio
[12:21:26 CET] <Lynne> funnybunny2: AVCodec->sample_fmts[]
[12:22:04 CET] <Arnob> So I should reencode to wav?
[12:22:45 CET] <c_14> It's already wav (pcm) you're going to have to encode to mp3, aac, alac (in mov) or opus
[12:22:56 CET] <c_14> or use .mkv instead of .mp4
[12:25:33 CET] <Arnob> ok, so to get the best audio, is it better to reencode to mp3 first then input the mp3 or keep the wav and output to mkv?
[12:25:42 CET] <funnybunny2> Lynne: I'm not talking about a single file. I'd like to know in terms of the specifications of audio codecs, which allow planar, interleaved, or both
[12:25:57 CET] <c_14> Arnob: you'll get the best audio by putting it in mkv. Because then you won't have to reencode it
[12:27:16 CET] <funnybunny2> I'm trying to decide if I need to support both planar and interleaved, or if the encodings I'm interested in all support one format or the other
[12:27:24 CET] <Arnob> c_14: ok, thank you!
[12:27:58 CET] <pink_mist> c_14: eh, if it's wav it's already lossless, so any other lossless encoding would work exactly as well
[12:28:06 CET] <pink_mist> such as alac or flac
[12:28:19 CET] <c_14> sure, but alac in mov isn't particularly common
[12:28:25 CET] <c_14> at that point might as well just stick to mkv
[12:29:04 CET] <funnybunny2> Am I misunderstanding? Does it depend on the specific decoder FFmpeg uses rather than the file format whether interleaved, planar, or both sample formats are supported?
[13:26:07 CET] <funnybunny2>  Arnob: You asked about getting the best audio. If you have a lossless
[13:26:24 CET] <funnybunny2> Arnob: ...wav file, it's obviously going to be worse if you encode it as mp3
[13:28:05 CET] <funnybunny2> Rereading, it seems like you're going to put the wav in an mkv. If that works, then good
[14:41:14 CET] <safinaskar> nut has very cool feature: it can store various types of uncompressed raw video: https://git.ffmpeg.org/gitweb/nut.git/blob/670ff4339ed54f779ece2086fe8dbe9cbd51db9d:/docs/nut4cc.txt . are there any other containers with similar feature?
[14:46:04 CET] <DHE> mkv is probably the "best" container in terms of features...
[15:13:05 CET] <LevelDrain> i have a better way for add list of musics to a video?
[15:13:11 CET] <LevelDrain> The only way I can find is to concatenate all the music in a single music file, and then put the music together with the video. Isn't there a way to do it all in one step?
[15:17:33 CET] <DHE> so you want a video to have an audio track that is a concatenation of all the music files you have?
[15:19:49 CET] <LevelDrain> DHE, yes, a video with a list of musics in the background...
[15:24:13 CET] <DHE> there are a few 'concat' options... file format, filters
[17:20:32 CET] <wowa_putin> test
[17:21:54 CET] <wowa_putin> hello everybody! How to fight problem of time drift from rtp h264 stream from IP Camera
[17:25:29 CET] <wowa_putin> for the moment i use the following code to obtain timestamp: picture->pkt_dts * av_q2d(stream->time_base)
[17:26:29 CET] <wowa_putin> it works fine for 15-20 mins. then there appears time drift that seems to left behind real time
[17:26:33 CET] <wowa_putin> what to doen?
[17:28:05 CET] <JEEB> so the pts/dts values stop going upwards properly?
[17:28:44 CET] <JEEB> RTP should have timestamps so it sounds like the input gets funky
[17:32:18 CET] <LevelDrain> DHE, what?...
[17:32:27 CET] <wowa_putin> hm, i am gonna give u more details
[17:37:09 CET] <wowa_putin> I have got 3 devices: very Jai go speed camera that gives me raw frames with timestamps, doppler effect radar that also gives me kind of frame (no pictures) with timestmap, and IP Camera. All timestamps of those devices are normalized to monotonic clock of pc. So, radar and jai camera work together just fine. Ip camera also for 10-20 mins, but then starts being behind. Do i make myself clear?
[17:42:20 CET] <wowa_putin> so, having that fact that Jai camera and Doppler radar work fine, i concluded there is problem with rtsp camera.
[17:46:53 CET] <shiin> I'm looking for a cli tool to search an audio track for noise spikes, to then print the timestamp of the audio/video file. Can ffmpeg do that?
[18:01:59 CET] <cousin_luigi> Greetings.
[18:03:45 CET] <cousin_luigi> I have a mpeg 4 video that corrupts during seek: what can I do to find out what's causing it and what can I do to improve the situation?
[18:05:54 CET] <LevelDrain> Greetings, mortal. Are you ready to die?
[18:07:33 CET] <LevelDrain> oh... it's ffmpeg... sorry...
[18:07:47 CET] <LevelDrain> bye...
[18:29:41 CET] <cousin_luigi> Can I add keyframes to a mpeg4 stream without recoding everything?
[18:30:23 CET] <pink_mist> not a chance
[18:30:58 CET] <cousin_luigi> ok
[18:48:32 CET] <cousin_luigi> ok, recoding fixed it. bbl!
[21:19:01 CET] <dinki> Hey guys.  I'm trying to upgrade to 4.2 on my Raspberry Pi Zero running rasbian buster and am having a whale of a time doing it.  Is the only way to get it running by building it?
[21:19:44 CET] <JEEB> there are some armv7 binaries built by some guy linked on the download page, but in general yes. I do recommend setting up a cross-compilation setup, though
[21:20:02 CET] <JEEB> so that you can use debian's ARM toolchain with a raspi sysroot
[21:20:06 CET] <JEEB> to build stuff on x86_64
[21:20:15 CET] <JEEB> and then just moving the binaries to the raspi
[21:20:38 CET] <DHE> rather than letting the Pi chew on building ffmpeg for an hour or two (?)
[21:21:10 CET] <JEEB> I always wondered why raspbian didn't offer something like that or documentation on how to get it set up
[21:21:30 CET] <JEEB> although in theory it shouldn't be too hard
[21:21:35 CET] <JEEB> 1) get sysroot under some dir
[21:21:38 CET] <dinki> TBH, I'm a fairly experienced linux user, but I'm very clumsy when it comes to building from source.  I tried using instructions from https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu  but am getting dependency issues and other isues
[21:21:42 CET] <JEEB> 2) try using the debian cross-compiler
[21:23:13 CET] <dinki> I do have an x86 debian server (Open Media Vault).
[21:23:50 CET] <furq> yeah it's pretty easy on debian/ubuntu/etc
[21:24:47 CET] <furq> pretty much just install crossbuild-essential-armhf and then install the deps you need with multiarch
[21:24:50 CET] <furq> https://wiki.debian.org/Multiarch/HOWTO
[21:25:37 CET] <dinki> Linux sign1 4.19.75+ #1270 Tue Sep 24 18:38:54 BST 2019 armv6l GNU/Linux
[21:25:45 CET] <dinki> So I'd build for armv6l ?
[21:25:50 CET] <JEEB> yup
[21:26:54 CET] <furq> i forget if you need armel or armhf on raspbian
[21:27:26 CET] <DHE> is that reported somewhere? /proc/cpuinfo or uname -a ?
[21:27:50 CET] <dinki> I'm pretty sure I've downloaded both precompiled binaries for armel and armhf and neither of them ran on my rpi
[21:28:17 CET] <dinki> @dhe see the uname I posted just above
[21:28:30 CET] <DHE> ah there it is
[21:28:36 CET] <furq> oh nvm it's a pi zero
[21:28:39 CET] <furq> that is armel then
[21:28:51 CET] <dinki> So I can download a precompiled armel version?
[21:28:57 CET] <furq> that should work
[21:29:01 CET] <furq> i've never used a zero though so shrug
[21:29:14 CET] <furq> the precompiled armhf version runs on my (non-raspbian) pi 2
[21:29:15 CET] <dinki> hmm.  Okay, let me try that again.  Pretty sure it seg faulted
[21:30:19 CET] <dinki> linux-armel , right?
[21:30:59 CET] <furq> https://johnvansickle.com/ffmpeg/releases/ffmpeg-release-armel-static.tar.xz
[23:07:59 CET] <dinki> @forq I tried that version and it seg faulted as before
[23:09:31 CET] <JEEB> yea, so you'll need to compile or cross-compile (latter preferably) it for the older ARM arch that the zero still utilizes
[23:17:49 CET] <dinki> @JEEB  is there a guide for compiling from source on the raspberry pi?  I'd rather just bite the bullet and do it rather than set it up to crosscompile only to be disappointed if it doesn't work.
[23:19:18 CET] <dinki> by the way, this is the error I'm getting if anyone can tell me what it might be from:
[23:19:19 CET] <dinki> /usr/bin/ffmpeg -loglevel error -y -f v4l2 -i /dev/video0 -f pulse -i default -codec:v libx264 -pix_fmt yuv420p -preset veryfast -b:v 500k -g 60 -codec:a aac -b:a 128k -ar 44100 -maxrate 500k -bufsize 250k -strict experimental -f flv
[23:19:19 CET] <dinki> rtmps://live-api-s.facebook.com:443/rtmp/111103643332502?s_bl=1&s_ps=1&s_sw=0&s_vt=api-s&a=AbzwuWpQlJ3859ds
[23:19:19 CET] <dinki> default: No such process
[23:25:06 CET] <darsie> hi
[23:26:37 CET] <darsie> https://pastebin.com/G45Y9NAB Unable to find a suitable output format for '1:1'
[23:26:38 CET] <darsie> 1:1: Invalid argument
[23:27:53 CET] <furq> -map 0:0 -map 1:1
[23:28:02 CET] <darsie> ffmpeg -i 0.mp4 -i 1.mp4 -map 0:0 1:1 -c copy out.mp4
[23:28:08 CET] <darsie> ah, thx.
[23:28:49 CET] <lavalike> what could it be if mpv playing an hls stream via youtube-dl prints out "cannot decode block" and "cabac" error messages every once in a while, disrupting the playback but not killing it altogether?
[23:29:18 CET] <JEEB> decoder having issues with decoding of the stream
[23:29:43 CET] <furq> yeah that sounds like the hls chunks have junk data at the start
[23:29:49 CET] <lavalike> it's boggling because on macOS nothing of the sort happens, on win10 it happens every time, with the same streams
[23:30:02 CET] <JEEB> is one of them using hwdec?
[23:30:08 CET] <lavalike> mac is
[23:30:08 CET] <JEEB> hwdec might just silently derp and not log
[23:30:15 CET] <JEEB> since that is not FFmpeg's decoder
[23:30:19 CET] <lavalike> good point
[23:30:56 CET] <JEEB> cabac is basically something like zip to make the coded data smaller in H.264/HEVC :P
[23:31:05 CET] <JEEB> so yes, issues trying to decode the coded packets
[23:31:07 CET] <lavalike> I see (:
[23:31:21 CET] <lavalike> I shall see if I can use any other decoder on windows I think
[23:33:11 CET] <darsie> marvellous, audio in sync perfectly till the end. thx! :)
[00:00:00 CET] --- Sun Dec  1 2019