[Ffmpeg-devel-irc] ffmpeg.log.20191109

Sun Nov 10 03:05:03 EET 2019

[03:55:49 CET] <aleksandrdvorkin> my makefile for kodi complains about error undefined reference to _atomic_store_8
[03:57:27 CET] <aleksandrdvorkin> it says to add set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -latomic")
[03:57:47 CET] <aleksandrdvorkin> which file do i add this line to
[03:58:13 CET] <JEEB> that's cmake, not utilized by FFmpeg's build system
[03:58:31 CET] <JEEB> also that's C++, of which there's like one or so module so that sounds all weird
[03:59:20 CET] <JEEB> I would recommend poking the kodi people because if something is recommending cmake changes then that's no longer normal FFmpeg?
[04:01:39 CET] <Ellenor> cmake is a troll
[04:13:03 CET] <taliho> aleksandrdvorkin: you could just try
[04:13:32 CET] <taliho> cmake .. -DCMAKE_CXX_FLAGS=-latomic
[04:15:06 CET] <aleksandrdvorkin> ok
[04:19:35 CET] <aleksandrdvorkin> taliho
[04:19:42 CET] <aleksandrdvorkin> so the entire command would be
[04:21:18 CET] <aleksandrdvorkin> cmake .. -DCMAKE_CXX_FLAGS=-latomic -DENABLE_INTERNAL-FLATBUFFERS=1 -DENABLE_INTERNAL_FMT=1 -DENABLE_INTERNAL_RapidJSON=1
[04:21:20 CET] <aleksandrdvorkin> ?
[04:23:54 CET] <taliho> you could try it
[04:26:34 CET] <aleksandrdvorkin> OK Because almost at 100% of the make install it complains about atomic_load_8 and atomic_store_8 error
[04:27:49 CET] <aleksandrdvorkin> i installed libatomic-ops-dev library but it still complains
[04:29:20 CET] <aleksandrdvorkin> then i read somewhere that a line set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -latomic"} can be added i supose to the makefile
[04:29:32 CET] <aleksandrdvorkin> but make file complains about missing seperator
[04:30:03 CET] <aleksandrdvorkin> maybe there is an error in that set command
[04:30:31 CET] <pink_mist> this is really not an ffmpeg issue, you should really take it up with the actual authors of the actual software you're having problems with
[04:30:44 CET] <taliho> is there a github page? i'll have a look at CMakeLists.txt
[04:31:48 CET] <aleksandrdvorkin> i am building now with -DCMAKE_CXX_FLAGS=-latomic option ALL OVER AGAIN
[04:32:40 CET] <aleksandrdvorkin> taliho you want to look at my CMakeLists.txt?
[04:33:47 CET] <aleksandrdvorkin> wait i ll look for the github page from which i install
[04:34:13 CET] <aleksandrdvorkin> https://github.com/xbmc/xbmc/blob/master/docs/README.RaspberryPi.md
[05:11:28 CET] <Skaface82> hey im trying to transcode a video, I want it to keep only the parts that contain motion and chop out the motionless parts, to make the video shorter in length. I have tried gt(scene,0.5) , decimate, and mpdecimate, but the videos always seem to have long sections of non-motion still in them. Any ideas?
[05:36:18 CET] <Atlenohen> [avi @ 00000208bc1cdb80] parser not found for codec ffv1, packets or times may be invalid.
[05:36:36 CET] <Atlenohen> so that means, ffprobe won't show accurate PTS for the packets/frames in an AVI ?
[05:37:04 CET] <Atlenohen> or FFV1 in general, i hope not
[06:37:50 CET] <Skaface82> i think ive figured out my problem
[10:45:31 CET] <mtcdood> I am unable to build ffmpeg with `--enable-libxml2` because it complains libxml-2.0 is not found by pkg-config
[10:45:54 CET] <mtcdood> `pkg-config --list-all` shows `libxml-2.0                       libXML - libXML library version2.`
[10:46:20 CET] <mtcdood> I aparently am the only person on the Internet to have this problem according to Google so does anyone have any advice?
[10:52:54 CET] <mtcdood> `/usr/bin/ld: cannot find -llzma`
[10:53:02 CET] <mtcdood> the error configure gives is not helpful
[10:53:14 CET] <mtcdood> it found libxml2, it could not find liblzma
[11:51:56 CET] <mtcdood> "https protocol not found, recompile FFmpeg with openssl, gnutls or securetransport enabled."
[11:51:59 CET] <mtcdood> yeah uh
[11:52:06 CET] <mtcdood> that should be enabled by default
[11:52:12 CET] <mtcdood> I can't fathom why it's not
[12:14:48 CET] <mtcdood> the current snapshot of ffmpeg uses 100% CPU to copy a DASH stream to disk, and doesn't actually write anything to console or disk
[12:15:20 CET] <mtcdood> Unable to read to offset 'manifest.mpd' into segfault
[13:42:54 CET] <grill05> I'm getting errors when compiling ffmpeg git+libaom git. The error looks like this
[13:42:55 CET] <grill05> In file included from src/libavcodec/libaomdec.c:26:
[13:42:55 CET] <grill05> /usr/local/include/aom/aom_decoder.h:101:3: error: unknown type name 'cfg_options_t'
[13:42:55 CET] <grill05>   101 |   cfg_options_t cfg;              /**< Options defined per config attributes */
[13:43:25 CET] <grill05> libaom (re-)added a new config-file option. The compile error seems to be related to that.
[14:16:53 CET] <Atlenohen> Hello
[14:17:17 CET] <Atlenohen> how do I display just the PTS and timecode stuff with ffprobe?
[14:17:35 CET] <Atlenohen> I remember there was an option to only show certain elements of the [frame]
[14:18:14 CET] <Atlenohen> so I can compare just PTS, i need to figure out whether a CFR video has no changes, whether it's really CFR or some frames don't add up
[14:18:38 CET] <Atlenohen> Or can FFprobe do some calc to tell me that automatically?
[14:59:55 CET] <Lypheo> ffprobe foo.mkv -select_streams v -show_entries frame=pkt_pts_time -of csv=nk=1:p=0
[15:00:07 CET] <Lypheo> will output each frames PTS
[15:29:34 CET] <cpplearner> Guys, I just built FFmpeg with `--enable-shared`, but `ld` fails to find the installed libraries. If I run ffmpeg, it shows `ffmpeg: error while loading shared libraries: libavdevice.so.58: cannot open shared object file: No such file or directory`.
[15:29:41 CET] <cpplearner> Any thoughts?
[15:31:29 CET] <cpplearner> Hmm, it tunes out that I had to manually add `LD_LIBRARY_PATH=/usr/local/lib ffmpeg` everytime I run ffmpeg. `/usr/loca/lib` isn
[15:31:35 CET] <cpplearner> 't the default library path?
[15:31:57 CET] <cpplearner> *`/usr/local/lib`
[15:47:56 CET] <DHE> that'll be an /etc/ld.so.conf thing, and run ldconfig once the install is done
[15:50:00 CET] <cpplearner> @DHE Thanks! That worked.
[16:44:46 CET] <Hello71> I don't think you really need to run ldconfig. iirc the cache doesn't cache negative entries
[16:44:59 CET] <Hello71> so if it's finding it in the wrong place, then you need ldconfig.
[19:04:48 CET] <jemius> what's the best way to get a high quality jpeg out of a video? If I take a single frame it naturally doesn't look good, as the eye has more time to examine the standing frame than in a video
[19:25:18 CET] <KombuchaKip> How do I retrieve the total number of frames in a given audio stream?
[19:26:12 CET] <KombuchaKip> Is that https://www.ffmpeg.org/doxygen/2.5/structAVStream.html#a4382c3064df1c9eb232ac198dec067f9 ?
[20:31:59 CET] <GenTooMan> how do you use frame counts in ffmpeg instead of times or is one stuck with time values only?
[21:07:05 CET] <CounterPillow> GenTooMan: modern codecs/containers do not work in a way where numbers of frames instead of timestamps would make any sense for seeking.
[22:51:14 CET] <alex```> Hi
[22:51:32 CET] <alex```> How to convert an mkv video to web?
[22:51:59 CET] <alex```> without loss or big size file
[22:52:23 CET] <alex```> I tried ffmpeg -i video.mkv out.webm
[22:52:42 CET] <alex```> but there is quality loss
[22:53:56 CET] <Reinhilde> -codec:v copy -codec:a copy
[22:54:04 CET] <Reinhilde> only works if it's vp8
[22:54:34 CET] <alex```> Reinhilde: what does `ffmpeg -i video.mkv out.webm`?
[22:54:49 CET] <alex```> compared to -codec
[22:55:17 CET] <jemius> re-encode, i supose
[22:55:28 CET] <alex```> does `-codec copy` is the same as `-codec:v copy -codec:a copy`?
[22:55:33 CET] <jemius> What does $ mediainfo file.mkv say ?
[22:55:51 CET] <Reinhilde> alex```: no
[22:55:58 CET] <Reinhilde> -codec without :v and :a is invalid now
[22:59:50 CET] <alex```> $ ffmpeg -i 2019-09-08_17:11:29.mkv -codec:v copy -codec:a copy out.webm
[22:59:57 CET] <alex```> # [webm @ 0x2139e40] Only VP8 or VP9 or AV1 video and Vorbis or Opus audio and WebVTT subtitles are supported for WebM.
[22:59:57 CET] <alex```> Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
[23:00:52 CET] <fresheyeball> holy cow there is a channel for this
[23:01:17 CET] <Reinhilde> alex```: that's because you don't have the right codec in the source
[23:01:34 CET] <fresheyeball> so I need to demux a mpeg-2 transport stream
[23:01:38 CET] <fresheyeball> to extract klv data
[23:01:48 CET] <jemius> alex```, the error message is rather acurate. To solve you're problem, you have to transcode to a valid codec. If the quality is not good enough, you have to configure the goal-codec's parameters
[23:01:54 CET] <fresheyeball> ffmpeg -i Sample_Data.ts -map data-re -codec copy -f data out
[23:01:59 CET] <fresheyeball> this works, but make a binary file
[23:02:05 CET] <fresheyeball> and I need something I can read in Python
[23:02:12 CET] <alex```> I dont know very well ffmpeg
[23:02:19 CET] <alex```> how do I do that?
[23:02:45 CET] <fresheyeball> is there a way I can access this time synced data in a sane way? Perhaps the binary is plenty good, but I don't understand it?
[23:04:17 CET] <Mavrik> fresheyeball, well.. depends on what is that data I guess?
[23:05:17 CET] <fresheyeball> Mavrik: its UAV data in the MISB standard
[23:05:20 CET] <Mavrik> You're probably just getting a dump of whatever there is inside the raw stream
[23:05:36 CET] <jemius> alex```, http://wiki.webmproject.org/ffmpeg/vp9-encoding-guide
[23:06:10 CET] <fresheyeball> Mavrik: what do you recommend?
[23:06:38 CET] <Mavrik> Reading up on the MISB standard and figuring out how to read it in python? :)
[23:06:43 CET] <Mavrik> This isn't really an ffmpeg per se
[23:07:08 CET] <fresheyeball> Mavrik: well yes. But first step is get access to the data
[23:07:13 CET] <Mavrik> You've dumped the raw data someone shoved into the video, now you just need to parse it and it's not really a video thing.
[23:07:29 CET] <alex```> jemius: thanks
[23:07:34 CET] <fresheyeball> Mavrik: I see, you are saying I am getting what they put
[23:07:36 CET] <Mavrik> You need to consult the documentation on whatever generated that data :)
[23:07:45 CET] <Mavrik> Since it's really not a standard thing.
[23:07:48 CET] <alex```> jemius: how do I know the names of the codecs?
[23:07:54 CET] <fresheyeball> and it's on me to parse it, there isn't a clear way to get metadata in a specific format
[23:07:59 CET] <fresheyeball> its just whatever got shoved
[23:08:01 CET] <fresheyeball> correct?
[23:08:23 CET] <Mavrik> Yes, correct.
[23:08:25 CET] <alex```> for example 'libvpx-vp9', where does the name come from
[23:08:32 CET] <jemius> alex```, ffmpeg -codecs
[23:08:35 CET] <Mavrik> ffmpeg just dumped the raw data into your file without doing anything to it
[23:08:37 CET] <alex```> thanks
[23:09:03 CET] <jemius> No problem. That would be 39$. Dou you prefer paypal?
[23:09:05 CET] <Mavrik> So the next step would be to try to figure out from the UAV doc or whatever, what kind of data it se.
[23:09:09 CET] <fresheyeball> Mavrik: ok cool, well thank you
[23:09:16 CET] <Mavrik> If it's KLV, you need to look up the size of keys I guess
[23:09:25 CET] <Mavrik> And then start by breaking up the raw data into keys and values.
[23:09:55 CET] <Mavrik> But, as I said, we can't really help you because what you have is very specific to whatever generated the video :)
[23:10:08 CET] <alex```> jemius: and what does `ffmpeg -i in.mkv out.mkv`
[23:10:26 CET] <alex```> how the re-encoding format is choose
[23:11:11 CET] <jemius> alex```, there are certain defaults. Usually it uses h.264. Depends on the container. The manpage might tell you something about it
[23:12:28 CET] <alex```> mpv tells me this (no -codec specified)
[23:12:41 CET] <alex```> (+) Video --vid=1 (*) (vp9 1896x1033 60.000fps)
[23:12:45 CET] <alex```> (+) Audio --aid=1 (*) (opus 2ch 48000Hz)
[23:13:29 CET] <alex```> the loss quality is very visible
[23:13:46 CET] <alex```> https://github.com/alexherbo2/krabby-resources/tree/master/demos/download-3-gatsu-no-lion-episodes-from-horriblesubs
[23:13:59 CET] <jemius> You have to specify a codec to specify a quality I guess
[23:14:46 CET] <alex```> the .webm is a bit fuzzy
[23:14:57 CET] <alex```> compared to original mkv
[23:15:06 CET] <alex```> I regret to have recorded my video in mkv :(
[23:15:23 CET] <alex```> it was intended to be shared on a webpage
[23:16:44 CET] <alex```> jemius: https://krabby.netlify.com/#demos videos looks fuzzy to you?
[23:16:59 CET] <alex```> (it's webm here)
[23:17:07 CET] <ps-auxw> Since your mkv contains vp9 + opus, you should be able to remux it to webm without reencoding.
[23:17:31 CET] <ps-auxw> Or was that your output?
[23:17:33 CET] <alex```> mpv tells me for mkv
[23:17:34 CET] <alex```> (+) Video --vid=1 (*) (h264 1896x1033 60.000fps)
[23:17:40 CET] <alex```> (+) Audio --aid=1 (*) (vorbis 2ch 48000Hz)
[23:17:47 CET] <ps-auxw> Ah, yes, that won't work.
[23:17:51 CET] <alex```> :(
[23:18:01 CET] <jemius> alex```, looks fine to me. What's your bitrate?
[23:18:03 CET] <ps-auxw> You can increase quality by increasind the bitrate, but it will make the file bigger.
[23:19:19 CET] <alex```> it looks fine but compared the mkv is super net
[23:19:37 CET] <alex```> https://github.com/alexherbo2/krabby-resources/blob/master/demos/download-3-gatsu-no-lion-episodes-from-horriblesubs/2019-09-08_17:11:29.mkv
[23:20:15 CET] <alex```> where do I see the bitrate
[23:21:00 CET] <jemius> alex```, did you even read the link I've send you?
[23:21:07 CET] <alex```> yes
[23:21:23 CET] <jemius> Then you specified the bitrate manually, didn't you?
[23:21:38 CET] <alex```> no
[23:21:54 CET] <alex```> ffmpeg -i 2019-09-08_17:11:29.mkv -codec:v libvpx-vp9 -codec:a libopus out.webm
[23:22:33 CET] <jemius> When you're on linux you can look up the bitrate with the program mediainfo
[23:22:42 CET] <alex```> I was afraid to use flags I was not sure their effect
[23:23:15 CET] <jemius> ffmpeg never changes the input files. Toy around by increasing the bitrate
[23:36:46 CET] <mrkotfw> Hello everyone
[23:36:55 CET] <alex```> yo
[23:37:26 CET] <mrkotfw> I have: "Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, progressive), 720x480 [SAR 32:27 DAR 16:9], 8000 kb/s, 29.97 fps, 59.94 tbr, 90k tbn, 59.94 tbc"
[23:37:36 CET] <mrkotfw> And a "Stream #0:6[0x22]: Subtitle: dvd_subtitle" stream
[23:37:48 CET] <mrkotfw> I'm attempting to overlay the subtitles onto the video stream
[23:38:04 CET] <alex```> jemius: thanks for mediainfo
[23:38:38 CET] <mrkotfw> Here is what I have: ffmpeg -analyzeduration 1000000k -probesize 1000000k -i MyMovie.vob -filter_complex "[0:v]copy[inv];[inv][0:s]overlay[outv]" -map "[outv]" -map 0:a:0 -c:a copy -t 00:00:30 -f dvd -y out.mp4
[23:38:49 CET] <mrkotfw> It works just fine, however the video quality is horrendous
[23:39:25 CET] <mrkotfw> And I don't understand why. Isn't the "copy" command simply copying exactly the video and simply overlaying?
[23:43:42 CET] <jemius> mrkotfw, -c:a copy means that only the audio stream is copied. You're filtering, therefore the video frames have to be reencoded
[23:44:16 CET] <DHE> there is a 'copy' filter but it's supposed to do nothing, effectively renaming [0:v] to [inv] for no useful reason
[23:48:32 CET] <mrkotfw> jemius: Understood. Is then there a way to re-encode according to whatever the video stream is?
[23:48:43 CET] <mrkotfw> DHE: I guess that's why the documentation says it's useful for testing
[23:49:31 CET] <mrkotfw> Do I need to somehow "configure" the subtitle stream and then pass that onto the overlay?
[23:52:15 CET] <DHE> well `overlay` requires a video stream. I think you want this instead: https://ffmpeg.org/ffmpeg-filters.html#subtitles-1
[00:00:00 CET] --- Sun Nov 10 2019