[Ffmpeg-devel-irc] ffmpeg.log.20150929

[burek]

[00:29:08 CEST] <votz> How can ffmpeg be instructed to stop stream copying at a keyframe? -ss before -i seeks to a keyframe and thus starts at a keyframe. What's the analog to stop at a keyframe?
[00:34:16 CEST] <waressearcher2> it should stop automatically, no ? at a nearest keyframe
[00:40:19 CEST] <votz> waressearcher2: unless I'm mistaken, it does not.
[03:33:40 CEST] <benzrf> hey!
[03:33:53 CEST] <benzrf> i have an mkv file that references another mkv file (two actually)
[03:34:01 CEST] <benzrf> is there a way to 'compile' them together into a single file?
[03:34:13 CEST] <benzrf> preferably without even any muxing; i just want to be able to serve it
[03:36:16 CEST] <benzrf> wait, 'muxing' is the wrong word there isnt it. ugh
[03:36:59 CEST] <klaxa> you can use mkvmerge for that: mkvmerge -o output.mkv input1.mkv + input2.mkv
[03:37:16 CEST] <klaxa> you can also use ffmpeg's concat demuxer: https://trac.ffmpeg.org/wiki/Concatenate
[03:37:26 CEST] <benzrf> cool, thanks!
[03:37:52 CEST] <klaxa> i'm not sure if you can do it based on references (do you mean chapters perhaps?)
[03:38:20 CEST] <benzrf> as in, playing it with mpv says:
[03:38:22 CEST] <benzrf> This file references data from other sources.
[03:38:24 CEST] <benzrf> Will scan other files in the same directory to find referenced sources.
[03:38:53 CEST] <klaxa> ah
[03:40:37 CEST] <benzrf> hmm
[03:41:25 CEST] <benzrf> augh
[03:42:00 CEST] <benzrf> klaxa: any ideas?
[03:42:04 CEST] <c_14> You can use the mkvmerge gui
[03:42:16 CEST] <c_14> Open the "main input" and then append all other files.
[03:42:20 CEST] <c_14> Then just mux to a new output
[03:42:39 CEST] <benzrf> :|
[03:42:40 CEST] <c_14> Don't have to worry about order since the virtual timeline will get that.
[03:42:42 CEST] <benzrf> i dont know this stuff
[03:43:00 CEST] <c_14> Install mkvtoolnix
[03:43:02 CEST] <benzrf> done
[03:43:06 CEST] <benzrf> already had it :}
[03:43:08 CEST] <c_14> open the mkvmerge gui
[03:43:16 CEST] <benzrf> oh, well. the gui version is installing :p
[03:43:33 CEST] <benzrf> kk
[03:43:56 CEST] <benzrf> er, what's the command for the gui
[03:44:02 CEST] <c_14> mkvmerge-gui iirc
[03:44:09 CEST] <benzrf> not in my PATH
[03:45:15 CEST] <c_14> What distro?
[03:45:43 CEST] <benzrf> well, my laptop is arch, but tbh i was hoping to merge the files on my VPS (which is ubuntu)
[03:45:49 CEST] <benzrf> however i'm having trouble with x forwarding
[03:45:51 CEST] <benzrf> :>>>>
[03:45:57 CEST] <benzrf> ~funtimes~
[03:46:30 CEST] <c_14> According to what I'm reading, what klaxa mentioned earlier with regards to mkvmerge -o output.mkv input.mkv + input2.mkv etc should work
[03:46:35 CEST] <benzrf> oh, is the + critical?
[03:46:37 CEST] <benzrf> :|
[03:46:39 CEST] <c_14> yes
[03:46:43 CEST] <benzrf> what does it mean
[03:46:55 CEST] <c_14> A single '+' causes the next file to be appended instead of added.
[03:47:25 CEST] <benzrf> what's the difference?
[03:47:37 CEST] Action: benzrf really needs to brush up on how media files work
[03:47:51 CEST] <klaxa> if you add the file, both files start at timestamp 0
[03:47:58 CEST] <klaxa> and you can switch between them in your player
[03:48:00 CEST] <c_14> All streams, anyway.
[03:48:00 CEST] <benzrf> ooh
[03:48:21 CEST] <klaxa> if you append a file, the second file starts at the timestamp when the first file ends
[03:48:29 CEST] <c_14> Unless there's a virtual timeline.
[03:48:35 CEST] <klaxa> that's wha the + does
[03:48:45 CEST] <c_14> Well, if the virtual timeline mentions the files to be appended.
[03:48:52 CEST] <benzrf> did not work :\
[03:48:59 CEST] <c_14> What did it output?
[03:49:49 CEST] <benzrf> Warning: The track number 1 from the file '<referenced file>' can probably not be appended correctly to the track number 1 from the file '<main file>': The codec's private data does not match (lengths: 8491 and 67880). Please make sure that the resulting file plays correctly the whole time. The author of this program will probably not give support for playback issues with the resulting file.
[03:49:55 CEST] <benzrf> and a similar error for 2
[03:50:20 CEST] Action: c_14 is installing mkvtoolnix on his system and will test with some of his files
[03:50:20 CEST] <benzrf> when i say 'did not work' i mean i opened it and it didnt work btw
[03:50:37 CEST] <benzrf> screw it ill just find another source for the media that doesnt do references
[03:50:39 CEST] <benzrf> ;-;
[03:50:58 CEST] <klaxa> can you run mkvinfo on all of the files and pastebin it?
[03:51:13 CEST] <klaxa> and maybe ffprobe too (for good measure?)
[03:51:26 CEST] <benzrf> th-that sounds like it might be work
[03:51:47 CEST] <klaxa> ok, well you can also just re-encode the file
[03:51:52 CEST] <klaxa> that will degrade quality though
[03:51:55 CEST] <klaxa> and take some time
[03:52:38 CEST] <benzrf> rip
[03:53:18 CEST] Action: benzrf finds an alternate source
[03:53:20 CEST] <benzrf> thanks anyway
[03:54:01 CEST] <klaxa> c_14: where do i find documentation about virtual timelines? i did not find it on matroska.org?
[03:54:36 CEST] <c_14> http://www.matroska.org/technical/specs/chapters/index.html
[03:54:49 CEST] <c_14> Though reading the manpage is better.
[03:54:53 CEST] <c_14> Not quite as technical.
[03:54:56 CEST] <klaxa> ah
[03:55:00 CEST] <klaxa> thanks
[03:55:49 CEST] <klaxa> wait, which manpage?
[03:56:10 CEST] <c_14> The mkvmerge one
[03:56:17 CEST] <c_14> Has a really big section on linking
[03:56:42 CEST] <c_14> Though it mainly goes into syntax.
[07:11:47 CEST] <pinPoint> anyone here write a gui front end to run with ffmpeg.
[11:04:18 CEST] <blez> hello
[11:04:36 CEST] <blez> I have this: ffmpeg -re -loop 1 -i test.jpg -r 10 -vcodec mpeg4 -f mpegts udp://127.0.0.1:1234
[11:04:51 CEST] <blez> I've tried to open udp://127.0.0.1:1234 with vlc to test, but nothing happened
[11:04:55 CEST] <blez> I wonder what's the problem
[11:06:14 CEST] <termos> are there any benchmarks running ffmpeg on multi-core arm cpus?
[11:20:44 CEST] <blez> someone?
[11:42:31 CEST] <iive> blez: doesn't loop 1 repeat the frame just once?
[11:42:59 CEST] <quovadis> Hi, I'm struggling converting rgb565 to gray: "-f rawvideo -pixel_format rgb565 -video_size 480x480  -i  tex.565 -f rawvideo  -pixel_format gray test.raw" any help ?
[11:43:00 CEST] <iive> hum,, no, i'm wrong, sorry
[12:15:24 CEST] <blez> iive no
[12:15:33 CEST] <blez> but the problem seems different
[12:15:42 CEST] <blez> when I try to use http:// I get "unknown error"
[12:40:05 CEST] <satiender> Hi , is there any why generate a C code for video encoding
[12:42:33 CEST] <satiender> ??
[12:42:43 CEST] <satiender> any one can help for that
[12:42:47 CEST] <satiender> please ??
[13:24:59 CEST] <superware> I'm playing a live h264 over udp stream, but sometimes (network glitches etc) the stream hangs indefinitely, while restarting ffmpeg continues playback. Since it's very hard to reproduce, I've made a very messed up stream which can reproduce the issue, please see http://pastebin.com/QuA5nCvQ line 229 seems to start the whole mess :)
[13:29:21 CEST] <voice> udp as the input?
[13:31:22 CEST] <superware> ffplay udp://192.168.19.121:40002
[13:31:24 CEST] <superware> yes
[13:32:13 CEST] <voice> I know I had problems with a UDP stream until I added ?fifo_size=1000000&overrun_nonfatal=1 to the end of the udp url
[13:32:49 CEST] <superware> let me check
[13:35:50 CEST] <superware> :( same, ffplay udp://192.168.19.121:40002?fifo_size=1000000&overrun_nonfatal=1
[13:46:44 CEST] <superware> voice: any other ideas?
[13:47:00 CEST] <voice> not off the top of my head unfortunately
[13:48:34 CEST] <superware> it's as if a specific packet/frame causes FFmpeg to enter a certain state from which it cannot recover
[13:49:52 CEST] <voice> all I know is with that url addon instead of a full quit I get a second or two freeze
[13:50:48 CEST] <superware> I guess my issue is more esoteric
[13:51:37 CEST] <voice> http://pastebin.com/pcRKbZZq that is what command my streaming script is using
[14:09:06 CEST] <DHE> ah, so it's not multicast then...
[14:12:19 CEST] <blez> I can't stream to http...
[14:12:47 CEST] <blez> ffmpeg -re -loop 1 -i test.jpg -r 10 -v 1 -f mp4 http://localhost:8787/test.mp4 // gives unknown error
[15:17:56 CEST] <Nolski> .close
[15:46:53 CEST] <xerox> Mavrik, DHE, thanks for the help the other day, by using your suggestions I have been able to achieve 43% of the original file size of my very still-image-y high res videos! I wonder if I can do even better, right now I'm using --preset slow --tune stillimage -qmax 30. Maybe lower the number of bframes?
[15:47:39 CEST] <DHE> if you're going for better compression, bframes are a good thing.
[15:48:45 CEST] <taolei> Hi, all. If I want to keep input's format unchanged, must I first know the format and use -f xxx to set output format? Can ffmpeg keep original format automatically?
[15:48:46 CEST] <xerox> oh right, the opposite then, have more of them, they are the most compressed ones
[15:49:53 CEST] <DHE> if you keep the same file extension then you should get the same container
[15:52:09 CEST] <xerox> DHE: what could be a good number to try?
[15:52:52 CEST] <mustafam> Hi, I want to capture using vlc and pipe raw video to ffmpeg, is this possible? thanks
[15:53:25 CEST] <DHE> xerox: I believe 2 to be the most common option especially in broadcast, though the codec permits up to 15
[15:59:37 CEST] <xerox> bframes=10:b-adapt=2 fun for all the family :D
[16:00:22 CEST] <taolei> Hi, DHE, the input is a stream, so there is no file extension. I want to record this stream and save to a file, is it possible to use the stream's format as the file's format automatically?
[16:02:09 CEST] <obiwahn> i am am recording a video and i wonder what i need to to in order to improve the quality of the video a bit
[16:02:23 CEST] <obiwahn> at the moment i use the following commandline:
[16:02:35 CEST] <obiwahn> ffmpeg -f x11grab -y -s "1920"x"1200" -i :0.0+0,0 -framerate 25 ~/video1.mkv
[16:03:50 CEST] <obiwahn> the image is a bit slushy (matschig)
[16:04:56 CEST] Action: taolei slaps taolei around a bit with a large trout
[16:05:38 CEST] <maldo> Hey. First time around here. I am streaming differents MP3 files publishing with ffmpeg. When a mp3 finish, the next one starts. I just want to know if it is possible to MIX the next audio file and fade out the finihing one and fadein the starting one. I guess not, but maybe something to explore...
[16:06:06 CEST] <maldo> Im publishing to a RTMP point.
[16:17:28 CEST] <durandal_170> maldo: afade, acrossfade filter
[16:17:37 CEST] <maldo> mmmmmmmm
[16:17:40 CEST] <maldo> GREAT
[16:17:42 CEST] <maldo> thanks
[17:37:31 CEST] <keyser7654> Hello! Are libavcodec API questions welcome here?
[17:45:54 CEST] <DHE> yes
[17:48:01 CEST] <keyser7654> I am decoding live rtp with H264 content and due to network packet loss i sometimes get the error: 'decode_slice_header error'. avcodec_decode_video2 does categorize this as a real error and returns a non negative value and a decoded frame.
[17:48:51 CEST] <keyser7654> how do I capture that error programatically? I can see it in my log callback, but at that stage I do not know exactly which decode context it is in reference to.
[17:49:25 CEST] <keyser7654> clarifcation: avcodec_decode_video2 does NOT mark this as error
[17:50:27 CEST] <keyser7654> using ffmpeg 2.7 and libx264
[19:09:10 CEST] <kyleogrg> hey
[19:11:12 CEST] <kyleogrg> so i am using a build helper to cross-compile ffmpeg for windows.  i can use the option "--disable-nonfree=n" to "include nonfree like libfdk-aac."  Do you know how I might include AAC HE as well?
[20:11:45 CEST] <Axydlbaaxr> Is anyone around?
[20:13:26 CEST] <durandal_1707> nobody, just you
[20:16:45 CEST] <ptomblin> My video camera records in "MOV" format, but breaks it up into chunks. I want to make a single file for input into Garmin VIRB Edit.
[20:17:12 CEST] <ptomblin> I've tried most of the ideas in https://trac.ffmpeg.org/wiki/Concatenate and most of them don't give me audio.
[20:17:30 CEST] <ptomblin> http://pastebin.com/yjTFcc18 and http://pastebin.com/RXUq9r5E
[20:18:00 CEST] <ptomblin> I've also tried the mmcat script but it takes 12 hours to process 1.5 hours of video.
[20:19:12 CEST] <Axydlbaaxr> Does anyone know how to set up ffserver so that it streams a video file as if it were live, so that clients connecting to it will get the video already in progress instead of from the beginning?
[20:19:57 CEST] <BtbN> ptomblin, remux to mpeg-ts first, and then use a concat list.
[20:20:21 CEST] <ptomblin> Isn't that what I'm doing in http://pastebin.com/yjTFcc18
[20:20:27 CEST] <ptomblin> ?
[00:00:00 CEST] --- Wed Sep 30 2015