[Ffmpeg-devel-irc] ffmpeg.log.20160417

burek burek021 at gmail.com
Mon Apr 18 02:05:01 CEST 2016


[00:06:05 CEST] <__raven> hm i tried some of your hints but i always get errors with input data :(
[00:09:09 CEST] <kepstin> __raven: well, first thing to check is whether ffmpeg can read all of your input files individually
[01:10:29 CEST] <speak> ffmpeg -i speak-motion.flac -i logo.png -filter_complex "[0:a]showcqt='axisfile=line.png: axis_h=2', format=yuv420p[vid]; [1:0]overlay=x=W-w-10:y=10" -map "[vid]" -map 0:a -codec:v libx264 -crf 18 -preset fast -codec:a aac -strict -2 -b:a 192k speak-motion_nofont.mp4
[01:10:38 CEST] <speak> I get "Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_overlay_2"
[01:11:06 CEST] <speak> I've had a bit of hard time finding good examples on filter_complex working on multiple inputs, so I know I'm doing it incorrectly somehow
[01:34:40 CEST] <rabelais> I'm trying to bring an overlay in to a video at a specific time and have it fade in. I was able to get the overlay to happen at the appropriate time (e.g., 3 seconds after the start of the video), but I can't seem to also get the fade in to happen as well, it says that fade doesn't support enable. Is there a way to do this?
[04:32:54 CEST] <prelude2004c2> hey guys.. good evening.. can someone help me.. as an input i am encoding and every time i rerun things the audio is always jumping around from the mapping .. is it possible to map things correctly on the input before i pipe it to the output for encoding
[04:32:56 CEST] <prelude2004c2> http://pastebin.com/Zcj8hs3E
[04:40:23 CEST] <prelude2004c2>   can anyone help?
[04:50:26 CEST] <Snoo20664> whats your line
[04:50:31 CEST] <Snoo20664> encoding line*
[04:52:13 CEST] <furq> prelude2004c2: which input do you want
[04:54:40 CEST] <prelude2004c2> "-map i:0x1011 -map i:0x1013 -map i:0x1015"
[04:54:43 CEST] <prelude2004c2> would something like that work ?
[04:54:51 CEST] <prelude2004c2> to keep them in order for transcoding ?
[04:55:02 CEST] <prelude2004c2> ignore the 0x values.. its from another sample
[04:55:37 CEST] <prelude2004c2> real one is " "-map i:0x1211 -map i:0x1216 -map i:0x1215" "
[04:55:41 CEST] <prelude2004c2> what do you think ? will that work ?
[04:55:44 CEST] <furq> if the pids are always the same then that should work
[05:26:24 CEST] <prelude2004c2> another question
[05:27:07 CEST] <prelude2004c2> for some reason the "     Stream #0:4[0x1215](san): Audio: mp2, 48000 Hz, stereo, s16p, 160 kb/s " is never copied over ? it shows that it has the input but transcoding never shows it
[05:27:16 CEST] <prelude2004c2> and i have c:a:0 and c:a:1 set
[05:27:22 CEST] <prelude2004c2> weird... i don't see an error
[05:27:52 CEST] <furq> don't set those if you're also mapping by pid
[05:28:16 CEST] <prelude2004c2> see http://pastebin.com/ZxchqKpn
[05:28:32 CEST] <prelude2004c2> but i have to down convert it to different bit rate
[05:28:45 CEST] <furq> oh
[05:29:01 CEST] <prelude2004c2> like .. i am taking the UDP transport stream.. i am running the -map i:xxxxx to sort the ones i want.. i took one " eng " and one " san "
[05:29:32 CEST] <prelude2004c2> then i am | ffmpeg -i - ... etc etc.. and converting from ac3 > aac and mp2 > aac
[05:29:45 CEST] <prelude2004c2> the ac3 > aac comes through... the mp2 > aac is completely ignored
[05:29:48 CEST] <prelude2004c2> odd.
[05:30:04 CEST] <furq> you can just use -map 0 to select all input streams
[05:30:34 CEST] <prelude2004c2> i dont want all though. sometimes it has multiple audio streams .. and i only want to select 2 max
[05:30:45 CEST] <prelude2004c2> sometimes it comes with like 4-5 audio streams
[05:31:12 CEST] <furq> the ffmpeg you're piping to will always have the same 3 streams
[05:32:04 CEST] <furq> although i'm not sure why you're piping it at all
[05:32:48 CEST] <prelude2004c2> oh why.. it was an old thing actually where i was setting up multiple bit rates and i was tee'ing it off to differnet work
[05:32:53 CEST] <prelude2004c2> i guess not really applicable at the moment :)
[05:32:59 CEST] <prelude2004c2> but i guess the problem is the same
[05:34:09 CEST] <prelude2004c2> the input on the pipe is correct. shows me all the audio i want and video
[05:34:24 CEST] <prelude2004c2> all is right.. its just that last encoding stage that is skipping the mp2 but its not telling me why
[06:13:40 CEST] <prelude2004c2> hey ffmpeg support cc ?
[06:13:51 CEST] <prelude2004c2> i don't seem to have that data too
[06:14:05 CEST] <prelude2004c2> using -scodec copy
[06:27:19 CEST] <furq> prelude2004c2: -c:s webvtt
[06:27:20 CEST] <furq> for hls
[06:27:31 CEST] <furq> assuming the ts has text subtitles, otherwise you'll need to convert them manually
[06:31:54 CEST] <prelude2004c2> not subtittles.. i want the closed caption data
[07:18:25 CEST] <sarmiena_> whats a good place to start learning about low latency streaming?
[07:18:32 CEST] <sarmiena_> wheres*
[07:47:49 CEST] <Snoo20664> i would just start experimenting sarmiena_
[07:48:05 CEST] <Snoo20664> and then asking an questions you have here as you go
[07:48:35 CEST] <sarmiena_> so just use the man pages & start messing around?
[07:48:53 CEST] <Snoo20664> yeah pretty much
[07:48:57 CEST] <sarmiena_> ok
[07:49:18 CEST] <Snoo20664> trial and error is best way to learn imo
[07:49:48 CEST] <sarmiena_> so far i got the streaming working from my isight on MBP, but theres massive latency. like 50 seconds
[07:50:00 CEST] <furq> what format are you using
[07:50:05 CEST] <sarmiena_> sec
[07:50:30 CEST] <sarmiena_> http://pastie.org/10800610
[07:50:53 CEST] <sarmiena_> then i run ffmpeg -f avfoundation -video_size 640x480 -framerate 30 -i "FaceTime" http://localhost:8090/feed1.ffm
[07:50:58 CEST] <furq> ffserver ;_;
[07:51:10 CEST] <sarmiena_> is that a bad thing?
[07:51:28 CEST] <furq> ffserver is not very good and on the brink of being abandoned
[07:51:37 CEST] <sarmiena_> whats the alternative?
[07:51:50 CEST] <furq> i would suggest using HLS, but that's not much use if you want low latency
[07:52:08 CEST] <furq> so the best alternative i know of is using an external streaming server
[07:52:30 CEST] <sarmiena_> i basically want to do something like& i guess surveilance camera or something?
[07:52:37 CEST] <furq> what kind of latency would be acceptable
[07:52:42 CEST] <sarmiena_> but that external streaming server gotta be setup somehow
[07:52:49 CEST] <sarmiena_> im thinking like 2 seconds
[07:53:01 CEST] <furq> yeah HLS and DASH are probably no good then
[07:53:30 CEST] <furq> the only thing i've used for streaming is nginx-rtmp, which you might be able to tune to <2 second latency
[07:53:38 CEST] <furq> someone else might be able to suggest a better alternative
[07:53:47 CEST] <sarmiena_> gotcha. thats interesting
[07:54:22 CEST] <sarmiena_> so just point the ffmpeg command as above to nginx-rtmp?
[07:54:26 CEST] <furq> yeah
[07:54:28 CEST] <furq> https://gist.github.com/fur-q/d7028f51c38f7d0bb56e
[07:54:31 CEST] <furq> the setup i use is there fwiw
[07:54:43 CEST] <furq> you can ignore the lua bit if you don't need stream authentication
[07:55:26 CEST] <sarmiena_> cool. thanks for the help furq !
[07:57:38 CEST] <furq> how are you currently viewing the streams btw
[07:57:49 CEST] <sarmiena_> just via web browser
[07:57:57 CEST] <furq> if it's in a browser then you'll need flash to view rtmp streams
[07:58:07 CEST] <sarmiena_> gotcha. that shouldnt be a problem
[07:58:16 CEST] <furq> ok good
[07:58:32 CEST] <furq> nginx-rtmp can also do hls and dash muxing, but the latency will be horrible
[07:58:35 CEST] <sarmiena_> i just want to stream video of something on my property for fun
[07:58:45 CEST] <sarmiena_> whats that stuff?
[07:58:58 CEST] <sarmiena_> hls and dash muxing
[07:59:05 CEST] <furq> https://en.wikipedia.org/wiki/HTTP_Live_Streaming and https://en.wikipedia.org/wiki/Dynamic_Adaptive_Streaming_over_HTTP
[08:00:25 CEST] <sarmiena_> so looks like those things are basically what i want to do
[08:00:36 CEST] <sarmiena_> so theres no hope?
[08:01:08 CEST] <furq> you'll struggle to get <5sec latency with HLS
[08:01:17 CEST] <furq> i've never used DASH but it works in a similar way so i'd expect it to be the same
[08:01:29 CEST] <sarmiena_> what else can be done?
[08:01:44 CEST] <sarmiena_> stream it directly to a player?
[08:01:53 CEST] <sarmiena_> like quicktime or something?
[08:02:07 CEST] <furq> if you use nginx-rtmp then most players can play rtmp urls
[08:02:39 CEST] <furq> you could also stream directly over udp with ffmpeg, but since it's not a proper server it'll only serve one client and stop running when the client disconnects
[08:04:09 CEST] <sarmiena_> what do you mean by stream directly over udp? like to a player directly?
[08:04:38 CEST] <furq> -i whatever udp://0.0.0.0:1234
[08:04:42 CEST] <furq> then open localhost:1234 in your player
[08:04:52 CEST] <furq> or your lan ip or whatever
[08:05:03 CEST] <furq> er
[08:05:09 CEST] <furq> -i whatever -f mpegts udp://0.0.0.0:1234
[08:05:19 CEST] <sarmiena_> ok
[08:05:32 CEST] <sarmiena_> and so with the nginx-rtmp thing. thats HLS, right?
[08:05:42 CEST] <furq> that's rtmp but it can also do hls and dash
[08:05:58 CEST] <furq> rtmp should do what you want
[08:06:10 CEST] <sarmiena_> the way you have it setup, its hls, yeah?
[08:06:18 CEST] <furq> it does both
[08:06:25 CEST] <furq> you can just disable hls if you don't need it
[08:07:09 CEST] <sarmiena_> i see. so say i do your setup. exact same setup. how do i view the stream? go to the browser?
[08:08:14 CEST] <furq> play rtmp://yourip:1935/live/streamname in your player or in a flash video player
[08:08:58 CEST] <sarmiena_> ok. i think its enough for me to start messing around. you in here a lot?
[08:09:08 CEST] <furq> sure
[08:09:14 CEST] <sarmiena_> cool
[08:09:29 CEST] <sarmiena_> thanks for the help dude
[13:45:10 CEST] <andrey_utkin_> fflogger8 !uncut me
[13:46:23 CEST] <andrey_utkin_> oh how to get that scripted request of uncut output
[15:29:53 CEST] <sopparus> hello
[15:30:03 CEST] <sopparus> anyone know if nvenc works on freebsd?
[15:39:20 CEST] <BtbN> sopparus, if the nvidia driver ships with the nvenc library, i'd guess so.
[15:59:44 CEST] <andrey_utkin_> is it a known issue that ffmpeg ends with zero retcode even though it gets a lot of h264 decoding errors and "-err_detect explode" is given? have just tried with 2.8.6 and recent git master
[16:03:00 CEST] <andrey_utkin_> it'd be much better if it returned failure retcode in such case, for git-bisect purpose
[16:54:08 CEST] <prelude2004c_Zzz> hey everyone.. can i get some help
[16:55:15 CEST] <prelude2004c_Zzz> http://pastebin.com/VVZ9GtJC
[16:55:35 CEST] <prelude2004c_Zzz> can someone have a look and tell me what i am doing wrong. Why does the second stream never come through
[17:45:55 CEST] <SpeakerToMeat> sfan5: Btw to revive a one month old discussion and then kill it because it's useless. Dad and I work in digital cinema and a lot of cinema and video professionals do not know that containers exist and about codecs
[17:46:35 CEST] <SpeakerToMeat> Question, I could swear there was a guide about installing non-libav ffmpeg on debian, but I can't find it... does anybody have the url perchance?
[17:46:40 CEST] <sfan5> i know that those exist
[17:46:46 CEST] <SpeakerToMeat> I'd like to avoid the dependency "hell" of compiling from source.
[17:46:48 CEST] <sfan5> i should get a job as video professional :P
[17:49:05 CEST] <SpeakerToMeat> Wait or am I wrong and is jessie or backports to jessie that's back onto ffmpeg?
[18:05:35 CEST] <SpeakerToMeat> Yes, it's in jessie-backports
[18:12:57 CEST] <r3volver> hiii!!!!
[18:13:01 CEST] <r3volver> ffmpeg -f alsa -r 16000 -i hw:2,0 -f video4linux2 -s 800x600 -i /dev/video0 -r 30 -f avi -vcodec mpeg4 -vtag xvid -qscale 0 -acodec libmp3lame -ab 96k output.avi
[18:13:26 CEST] <r3volver> this command does not work because the audio hw ID is wrong
[18:13:32 CEST] <r3volver> how can i discover the right id?
[18:13:44 CEST] <r3volver> [alsa @ 0x563158d4eca0] cannot open audio device hw:2,0 (No such file or directory)
[18:13:47 CEST] <r3volver> hw:2,0: Input/output error
[18:14:03 CEST] <r3volver> if i remove the audio configuration in the command, it works fine.
[18:14:04 CEST] <r3volver> =D
[18:14:36 CEST] <sopparus> aplay -l I think
[18:14:45 CEST] <sopparus> something simular
[18:15:25 CEST] <r3volver> sopparus: its from the alsa suite right?
[18:15:32 CEST] <r3volver> sopparus: outside ffmpeg
[18:15:44 CEST] <sopparus> yes
[18:16:11 CEST] <r3volver> it worked. thank you very much
[18:16:13 CEST] <r3volver> =D
[18:16:17 CEST] <r3volver> testing it right now
[18:34:12 CEST] <rabelais> I'm trying to bring an overlay in to a video at a specific time and have it fade in. I was able to get the overlay to happen at the appropriate time (e.g., 3 seconds after the start of the video), but I can't seem to also get the fade in to happen as well, it says that fade doesn't support enable. Is what I'm hoping to do possible?
[19:53:57 CEST] <prelude2004c> hey guys.. not sure i got an answer the last time but i am having some trouble with audio
[19:54:04 CEST] <prelude2004c> see : http://pastebin.com/MSvYUQBa
[19:54:18 CEST] <prelude2004c> not sure why the 2nd audio channel never gets encoded.. any ideas?
[20:43:17 CEST] <DHE> prelude2004c: what does "-map i:0x1022" do?
[20:44:38 CEST] <DHE> in fact, show us the real comand-line and not just cherry-picked output only
[21:51:13 CEST] <PacketPusha> I can's quite seem to get this figured out,  I am using "ffmpeg -y -threads 8 -i "video.mp4" -an -sn -vsync 0 -vframes 10 -s 854x480 -vcodec mjpeg -pix_fmt yuvj420p -b:v 2000 -bt 20M "test_%d.jpg" -ss 10" so far but I want to skip the first 10 seconds and then every 30 seconds get 10 frames as images.
[21:51:17 CEST] <PacketPusha> Suggestions?
[21:54:40 CEST] <prelude2004c> hey DHE sorry for the delayed response
[21:56:20 CEST] <prelude2004c> please see full command here
[21:56:21 CEST] <prelude2004c> http://pastebin.com/tVi1BhQU
[22:11:06 CEST] <prelude2004c> so , anyone able to help ?
[22:11:12 CEST] <prelude2004c> i am stuck on this last item
[22:22:28 CEST] <jcd> Hi!
[22:22:34 CEST] <jcd> Is anyone listening?
[22:23:22 CEST] <jcd> I need perform phase reversal on an audio track
[22:23:30 CEST] <jcd> (actually lots of them)
[22:23:46 CEST] <jcd> but I haven't found a way to do it in the documentation
[22:24:12 CEST] <jcd> Has anyone got any idea where to look?
[22:24:29 CEST] <TAFB> I want ffmpeg to stream a short video in a loop put insert random .mp3 audio songs, possible?
[22:24:40 CEST] <TAFB> but insert...
[22:27:30 CEST] <TAFB2> I want ffmpeg to stream a short video in a loop but insert random .mp3 audio songs, possible?
[22:47:30 CEST] <livingBEEF> Is it at all possible to get size of a stream with ffprobe or something? As far as I can tell, the only way is to extract the stream with -c:copy and look at the file size..
[22:47:53 CEST] <livingBEEF> Which isn't exactly practical, especially with bigger files
[22:55:35 CEST] <Snoo20664> you can use mediainfo to get the stream sizes
[22:58:45 CEST] <livingBEEF> This seems to work "ffmpeg -i <vid> -c copy -map <stream> -f <fmt> - | wc -c"
[22:59:13 CEST] <livingBEEF> Thanks for the tip though.
[23:00:50 CEST] <livingBEEF> Still, it would be nice if ffprobe could calculate avg bitrate when hard bitrate is not present.
[00:00:00 CEST] --- Mon Apr 18 2016


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