[Ffmpeg-devel-irc] ffmpeg.log.20171217

burek burek021 at gmail.com
Mon Dec 18 03:05:01 EET 2017


[00:01:54 CET] <Cracki> I've got variable-frame-rate mjpeg data. ffmpeg with "c copy -r" on output doesn't seem to drop/duplicate any frames. must I reencode the frames or can ffmpeg drop/duplicate compressed frames?
[00:02:16 CET] <Cracki> *-c copy -r 25
[00:06:36 CET] <furq> -r is a noop with -c copy because it uses a filter
[00:06:55 CET] <Cracki> k
[00:07:11 CET] <furq> there's probably a way of doing it but idk how you'd do it with ffmpeg
[00:07:23 CET] <Cracki> btw, is there a frame rate filter that blends frames together instead of dropping frames?
[00:07:38 CET] <furq> !filter minterpolate
[00:07:38 CET] <nfobot> furq: http://ffmpeg.org/ffmpeg-filters.html#minterpolate
[00:07:44 CET] <Cracki> nice
[00:08:03 CET] <Cracki> my intention is to get "long exposure"
[00:08:10 CET] <furq> that blends instead of duplicating but idk if it blends instead of dropping
[00:08:53 CET] <furq> !filter blend
[00:08:53 CET] <nfobot> furq: http://ffmpeg.org/ffmpeg-filters.html#blend_002c-tblend
[00:09:00 CET] <furq> there's that as well but that's less sophisticated
[00:09:06 CET] <Cracki> so if I had 50 fps video with 20ms exposure per frame, and I'd blend them down to 25 fps, I'd expect 40ms of "exposure"
[00:09:19 CET] <furq> i think blend will do that
[00:10:09 CET] <Cracki> I think I'll use minterpolate. that's close to what I want.
[00:39:29 CET] <Cracki> is there a kind of motion (temporal) blur filter? I'm testing hqdn3d right now, but not sure if "denoising" is what I want
[00:40:15 CET] <sfan5> denoising is definitely not what you want
[00:44:10 CET] <Cracki> eh, I should just get the recording under control
[00:44:55 CET] <Cracki> (c920 webcam can spew h264 or mjpeg which ffmpeg can catch, but it's tricky to fix the servo focus, make sure the frame rate stays constant, all that stuff
[00:47:09 CET] <Cracki> ah, tblend *might* do it, but it's more suited to decimation
[00:48:56 CET] <Cracki> oh, tblend does maintain frame rate! interesting
[00:51:42 CET] <Cracki> it seems restricted to two frames though
[00:56:16 CET] <Cracki> so I'm poking around in the source of the blend filter.
[00:56:33 CET] <Cracki> i see that lighten is FFMAX(), but I can't see which color space and which components that applies to
[00:58:06 CET] <Cracki> nvm, it says "all components" :P
[01:16:06 CET] <Johnjay> ffmax()!
[03:27:13 CET] <WireCat> which is the correct current example of demuxing and decoding video using the libraries? i tried some on google and such they say '..is deprecated' and other stuff.
[03:27:47 CET] <furq> https://www.ffmpeg.org/doxygen/trunk/examples.html
[03:27:49 CET] <furq> probably these
[03:30:45 CET] <WireCat> ok thank you ill try those again
[03:31:59 CET] <WireCat> i just wanted to make sure, i tried them and it gave some errors and then i tried google and those gave different error. got confused in the end. i hope it will work this time :-)
[03:33:07 CET] <furq> make sure you're using the examples for the right version of ffmpeg
[03:37:39 CET] <WireCat> ah maybe that was the problem im not sure  i checked that very well
[03:38:14 CET] <WireCat> i had to build it from source because the packaged one didnt work for my distro, did segfaults.
[03:38:36 CET] <WireCat> maybe i just used an older version example by accident
[03:51:16 CET] <Cracki> H.264, can a P-frame use other P-frames as reference, or only I-frames?
[03:52:38 CET] <Cracki> I know about "rolling I-frames"/intra refresh, so either the answer is 'yes', or it can reference intra-*blocks* (finer than frames)
[03:54:38 CET] <DHE> Cracki: it can use any frame prior to itself, but only prior. and up to a limited number of frames behind it
[03:54:44 CET] <Cracki> k
[03:55:19 CET] <DHE> WireCat: the samples are in the doc/examples directory of the source tree. use what ships with your copy of ffmpeg...
[03:58:32 CET] <WireCat> dhe thank you
[03:59:59 CET] <TheRock> i'm using ffmpeg as backend through a library.
[04:00:06 CET] <TheRock> It throws me error code 14, video codec not found.
[04:00:12 CET] <TheRock> where can i find the error codes?
[04:02:32 CET] <TheRock> ok, it seems it has it's own error codes
[04:02:49 CET] <SortaCore> libavutil\error.c, but that won't help ya, since the error code has the description already
[04:04:38 CET] <TheRock> yeah, but i need to do something like if(error == 14) { own error message } since my application may be come multilingual.
[04:04:49 CET] <TheRock> but i just saw my library uses it's own error code https://github.com/wang-bin/QtAV/blob/master/src/QtAV/AVError.h#L31
[04:05:13 CET] <TheRock> it differs from the error.c
[04:05:42 CET] <SortaCore> indeed
[04:06:00 CET] <SortaCore> but you can find the largest number used in error.c and change your enum
[04:06:12 CET] <SortaCore> I think ffmpeg errors are negative
[04:07:06 CET] <TheRock> yeah, i'm just getting "video codec not found"
[04:07:12 CET] <TheRock> i'm playing a mp3 file
[04:07:30 CET] <TheRock> probably the mp3 is corrupt/wrong formated?
[04:07:38 CET] <TheRock> other mp3 work fine without error
[04:10:52 CET] <SortaCore> mp3 has no video
[04:11:15 CET] <SortaCore> do you mean mp4?
[04:11:15 CET] <TheRock> weird
[04:11:19 CET] <TheRock> no, mp3
[04:11:24 CET] <TheRock> it throw video codec not found
[04:11:27 CET] <SortaCore> yea, no video then
[04:11:36 CET] <TheRock> but all other mp3s are working well
[04:11:39 CET] <TheRock> just one
[04:11:50 CET] <TheRock> says it's video codec can't be found when playing
[04:12:12 CET] <TheRock> but then continues to play the audio
[04:32:22 CET] <SortaCore> that's odd
[04:32:26 CET] <SortaCore> run ffprobe?
[04:38:46 CET] <TheRock> see here
[04:38:50 CET] <TheRock> https://nopaste.xyz/?f62bacaa9ea4f30c#ibCfFaBez2lZlyiMr9rhT9kJixpR4Gkj9L2DKN2aa+c=
[04:39:12 CET] <TheRock> looks like it contains video?
[04:39:13 CET] <TheRock> Stream #0:1: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown), 500x500 [SAR 72:72 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
[04:39:21 CET] <TheRock> it's a mp3
[04:39:30 CET] <Cracki> 500x500, might be a cover?
[04:39:36 CET] <TheRock> yeah there is a cover
[04:40:12 CET] <TheRock> I use ffmpeg without mjpeg
[04:40:14 CET] <TheRock> own build
[04:40:19 CET] <TheRock> that's the problem, probbly?
[04:40:25 CET] <TheRock> probably
[04:41:20 CET] <Cracki> it's prolly an mpeg2 container, but ffmpeg didn't say that
[04:42:08 CET] <TheRock> hmm
[04:42:18 CET] <TheRock> so as plain mp3 it couldn't have a cover?
[04:42:27 CET] <Cracki> no no this is right
[04:42:43 CET] <Cracki> "mp3" can be an unmuxed mpeg2 layer 3 audio stream
[04:42:50 CET] <Cracki> or it can be mpeg2 container + stream inside it
[04:42:58 CET] <TheRock> ah, ok
[04:43:04 CET] <TheRock> I did not build ffmpeg with mpeg2
[04:43:06 CET] <TheRock> from what i remember
[04:43:12 CET] <TheRock> only mpeg
[04:43:13 CET] <TheRock> 4
[04:43:13 CET] <Cracki> since ffmpeg found an mjpeg stream, it's prolly properly containered
[04:43:25 CET] <Cracki> mpeg2 is a whole standard
[04:43:35 CET] <TheRock> yeah makes sense
[04:43:37 CET] <Cracki> the demuxers should be available anyway
[04:43:46 CET] <TheRock> yeah the audio is playing well, but it raises an error
[04:43:49 CET] <TheRock> in my app
[04:43:54 CET] <Cracki> so don't decode the video ¯\_(Ä)_/¯
[04:44:26 CET] <TheRock> that's not so easy, the user add his videos/audios
[04:44:59 CET] <TheRock> the best is probably to rebuild with mpeg2 support
[04:49:29 CET] <Cracki> no
[04:49:35 CET] <Cracki> you check which streams the container has.
[04:49:45 CET] <Cracki> and you only decode the audio stream.
[04:53:26 CET] <TheRock> yeah
[04:53:30 CET] <TheRock> but:
[04:53:37 CET] <TheRock> my window is anyway black when mp3 is played
[04:53:52 CET] <TheRock> so it wouldn't harm if there is a jpeg displayed
[04:54:29 CET] <SortaCore> isn't it -nv command?
[04:59:02 CET] <Cracki> -vn
[04:59:39 CET] <Cracki> and that's for command line use, not if you use the library
[04:59:55 CET] <Cracki> only god knows what the rock uses
[05:05:31 CET] <TheRock> you guys already helped me
[05:05:36 CET] <TheRock> i thought it was a bug in the library
[06:17:05 CET] <SortaCore> weird, my RTSP copy codec is doubling the output time (codec time_base)
[06:18:54 CET] <SortaCore> even though I manually set the time base to the normal, it doubles in the output
[06:36:54 CET] <Cracki> your codec? your bug?
[06:53:28 CET] <SortaCore> nah
[06:53:41 CET] <SortaCore> well, it's my C++, but not a new codec
[06:54:00 CET] <SortaCore> I'm just copying directly from RTSP H264 decoder to MP4 video file encoder
[06:54:29 CET] <SortaCore> and I set the time_base to tbc 12, and it doubles to tbc 24
[07:05:30 CET] <SortaCore> it may be to do with the fact the framerate is 6
[07:05:35 CET] <SortaCore> so h264 may automatically double it
[07:11:53 CET] <SortaCore> hence 6 -> 12, and for me 12 -> 24
[07:13:27 CET] <SortaCore> double the context->time_base.num works ok
[07:13:42 CET] <SortaCore> but the duration on the file is a mess
[07:20:55 CET] <SortaCore> Frame rate: 0.155864 instead of 6
[07:45:29 CET] <johnnny22> I'm trying to capture 7.1 audio from a pulse source (index 0) using something like ffmpeg -f pulse -channels 8 -i 0 output.nut   just for testing purposes. Now this gives me a "0: No such process" error. If I lower that -channels value to 6  it works and the output is 5.1 audio. Any idea what I might be missing ?
[07:46:34 CET] <johnnny22> The source is 8 channels according to "pactl list sources"
[08:25:59 CET] <WireCat> why would the swscale thing tell me 'bad dst image pointers'
[08:50:07 CET] <SortaCore> anyone know why copying RTSP H264 to video file results in duration of 21 minutes?
[08:50:48 CET] <SortaCore>  the actual length is 22 seconds
[08:55:49 CET] <SortaCore> works okay if I transcode
[09:15:22 CET] <SortaCore> ticks_per_frame seems to be the cause of double-speed, but I can't fix the duration
[09:36:58 CET] <SortaCore> no one got a tip?
[09:39:44 CET] <SortaCore> looks like frame rate is butchered
[09:43:08 CET] <SortaCore> but I explicitly set r_frame_rate and avg_frame_rate to match the source
[09:43:12 CET] <SortaCore> any idea?
[10:32:27 CET] <bob12421> Hello
[10:32:44 CET] <bob12421> Is there a way to increase -rtbufsize beyond INT_MAX?
[10:35:15 CET] <bob12421> Could I compile it with 64-bit integer type?
[10:43:03 CET] <bob1241> I'm trying to capture 4K video but nothing works.
[10:47:03 CET] <furq> bob1241: you're going to need a fast ssd (or better) to capture 4k rawvideo
[10:47:25 CET] <furq> all the buffer in the world isn't going to help unless you have storage that can keep up
[11:25:29 CET] <bob1241> fruq, I've tried writing to a ram disk but no change
[22:00:54 CET] <picks_> I'm having some issues with trying to copy an encrypted m3u8 stream
[22:00:58 CET] <picks_> here's the log https://pastebin.com/NuUjKxcF
[22:01:13 CET] <picks_> after a few .ts files have been processed ffmpeg appears to fail
[22:01:54 CET] <picks_> but I'm not certain why. I've tried other HLS streams (from the same provider) and the issues remains
[22:16:49 CET] <ender948> ubitux
[23:02:50 CET] <DHE> picks_: well that's the point of encryption. the keyserver isn't giving you a useful key so ffmpeg can't copy it. maybe you're missing HTTP cookies or such.
[23:14:12 CET] <picks_> can I inject (for want of a better word) those cookies into ffmpeg
[23:23:25 CET] <DHE> dunno. but do you even have the cookies to inject?
[23:29:52 CET] <prelude2004c> hey everyone..
[23:29:59 CET] <prelude2004c> hey everyone.. installed cuda 9.1 on linux.. trying to compile ffmpeg with cuda enabled and it says " cuvid not found " whats upw ith that ?
[23:30:19 CET] <prelude2004c> anyone know.. cuda is found in /usr/local/cuda
[23:30:25 CET] <durandal_1707> have headers?
[23:32:02 CET] <prelude2004c> yup installed
[23:33:18 CET] <prelude2004c> been at this for 2 hours now.. i'm blown away..
[23:33:47 CET] <prelude2004c> path is there.. i even did a cflag includes and ldflag path and still nothing
[23:34:03 CET] <prelude2004c> seems /usr/lib/x86_64-linux-gnu/libnvcuvid.so
[23:34:10 CET] <durandal_1707> prelude2004c: pastebin config.log
[23:34:14 CET] <prelude2004c> i even tried a symbolic link
[23:34:33 CET] <prelude2004c> last error is : /tmp/ffconf.JJgJBSZh.c:1:22: fatal error: cuviddec.h: No such file or directory
[23:35:07 CET] <prelude2004c> not sure how to get that
[23:35:12 CET] <durandal_1707> where is your cuviddec.h now?
[23:35:41 CET] <prelude2004c> seems in 9.1 its like /usr/local/cuda-9.1/include/dynlink_cuviddec.h
[23:35:51 CET] <prelude2004c> it has dynlink so i guess it can't find it
[23:36:39 CET] <prelude2004c> should i change the configure ?
[23:36:42 CET] <prelude2004c> it's weird.
[23:36:54 CET] <durandal_1707> dunno
[23:37:06 CET] <durandal_1707> try to copy file instead
[23:37:33 CET] <prelude2004c> hey good idea
[23:40:32 CET] <prelude2004c> it went past the error.. i guess developers should consider that going forward
[23:40:33 CET] <prelude2004c> :)
[23:41:03 CET] <prelude2004c> maybe i have an old ffmpeg version
[23:43:10 CET] <prelude2004c> last question.. libnpp not found... which does enables that ?
[23:43:34 CET] <prelude2004c> with module do i have to install.. tried the ones that i saw that had to do with it but.. nothing .. still complaining
[23:44:26 CET] <durandal_1707> do you have libnpp installed?
[23:47:05 CET] <prelude2004c> not sure which file it is
[23:47:10 CET] <prelude2004c> i tried installing the ones i found  but..
[23:48:20 CET] <prelude2004c>  --extra-cflags=-I/usr/local/cuda/include
[23:48:29 CET] <prelude2004c> they are in there... but for some reason configure doesn't see it
[23:48:59 CET] <durandal_1707> look again in last line of log
[23:50:46 CET] <prelude2004c> yes /usr/bin/ld: cannot find -lnppi ..
[23:50:55 CET] <prelude2004c> but not sure what to grab to install that :(
[23:51:01 CET] <prelude2004c> tried the ones in repo .. nada
[23:51:54 CET] <durandal_1707> try to locate libnpp.so file
[23:52:37 CET] <durandal_1707> ldflags are used for -libs
[23:53:59 CET] <BtbN> prelude2004c, I have no clue what you are building there, but ffmpeg configure does not have a check for cuviddec.h. That header is bundled and does not need any external SDK.
[23:54:27 CET] <BtbN> Is that libav?
[23:54:36 CET] <prelude2004c> well i have 2 nvidia cards
[23:54:46 CET] <prelude2004c> and i am trying to use ffmpeg to transcode using the video cards
[23:54:54 CET] <prelude2004c> so... i installed the nvidia drivers.. they see the cards.. i installed cuda
[23:55:08 CET] <BtbN> ffmpeg does not need anything but the nvidia drivers at runtime for that
[23:55:15 CET] <prelude2004c> now i am trying to compile.. i'm past the cuviddec error by simply copying it
[23:55:18 CET] <BtbN> no special build time dependencies. Any default build of ffmpeg will have support.
[23:55:31 CET] <BtbN> So, again, what are you building there? It can't be ffmpeg.
[23:55:37 CET] <prelude2004c> hum.. weird.. well i am trying to get cuvid going
[23:55:39 CET] <prelude2004c> i need that
[23:55:55 CET] <BtbN> cuvid/nvdec is bundled and works out of the box unless you explicitly disable it
[23:56:08 CET] <prelude2004c> weird.....
[23:56:29 CET] <durandal_1707> whats you configure invocation?
[00:00:00 CET] --- Mon Dec 18 2017


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