[Ffmpeg-devel-irc] ffmpeg.log.20181225

[burek]

[00:51:57 CET] <luddite478> Hi, can suggest me the way to pass ffmpeg stream through my python script with opencv? Details here: https://stackoverflow.com/questions/53906765/pass-ffmpeg-stream-through-python-script
[08:21:03 CET] <Trilom> Greetings, looking to see if anyone is interested in taking a crack at something. I am following the compile guide at https://trac.ffmpeg.org/wiki/CompilationGuide/Centos for Centos7 and keep running into the same issue when I attempt to build FFMPEG after building all deps. Here is the error "STDOUT: ERROR: freetype2 not found using pkg-config" It is very similar if not identical to: https://superuser.com/questions/1366977/install-ffm
[08:25:57 CET] <pink_mist> I mean ... did you try the obvious thing? installing freetype2?
[08:28:09 CET] <Trilom> Yes, similar to the linked superuser post, pkg-config --exists freetype2 || echo 'no lib' shows freetype2 exists, rpm -q freetype shows freetype-2.8-12.el7.x86_64, and --cflags are set for pkg-config to -I/usr/include/freetype2 -I/usr/include/libpng15
[08:30:34 CET] <pink_mist> well
[08:30:39 CET] <pink_mist> you're on centos
[08:30:54 CET] <pink_mist> so having freetype installed doesn't mean you have all of freetype installed
[08:31:02 CET] <pink_mist> you'll need freetype-devel too
[08:31:31 CET] <Trilom> Here ya go: [vagrant at GS-l-centos-74 ~]$ rpm -q freetype-devel freetype-devel-2.8-12.el7.x86_64
[08:31:43 CET] <Trilom> Allegedly both should be there.
[08:32:03 CET] <Trilom> I even tried downgrading to a lower version of freetype 2.4 or something.
[08:33:11 CET] <Trilom> The compilation guide says to install freetype-devel, which freetype depends on.
[08:33:35 CET] <pink_mist> no idea then ... ffmpeg compiles fine on my slackware machine
[11:07:05 CET] <scramblez> Happy Xmas to all! I'm trying to concatenate 4 avi files but without the audio of the first file. So, I first used -na to remove the audio stream of the first avi file and then concatenated them. However, the result is a file with no audio stream. :( How could I fix this?
[11:07:43 CET] <durandal_1707> full uncut ffmpeg command and output missing
[11:15:48 CET] <scramblez> Thanks durandal_1707, here it is:  https://pastebin.com/nrJT2Jbc
[11:17:24 CET] <durandal_1707> please do not ever use concat protocol
[11:17:53 CET] <scramblez> Ohh!  What should I be using instead?
[11:18:12 CET] <durandal_1707> use concat demuxer, and make sure that parameters like width/height and pixel format match
[11:18:53 CET] <durandal_1707> http://trac.ffmpeg.org/wiki/Concatenate#demuxer
[11:19:59 CET] <scramblez> Thanks, I think this is how I had done it last time I tried the same - I can't recall having problems back then.  Will give it another go.
[11:29:12 CET] <scramblez> Hmm ... still no audio, although it seems to find the audio stream from the second file onward: https://pastebin.com/Y3rqr3uN
[11:30:37 CET] <scramblez> BTW, all video files parameters are the same, other than audio being removed from the first.
[11:52:02 CET] <durandal_1707> you can not expect to have audio if you removed it from first
[12:04:06 CET] <scramblez> durandal_1707: is it then possible to zero the volume on the first video's audio stream so it is not audible?  This way all files will have their audio stream.
[12:09:48 CET] <durandal_1707> scramblez: if you encode silence with same parameters as other files with same audio codec
[13:04:35 CET] <scramblez> THanks durandal_1707, will give it a go later and see what I get.
[13:14:10 CET] <bmcginty> I've tried searching for this with no luck. Is there a way to have ffmpeg fail to convert a file if it doesn't have at least one audio stream? (I know there's -map for selection, but it doesn't _require a stream type to be present I believe.)
[14:44:09 CET] <JEEB> bmcginty: I think unless you specify a special thing with map it will fail you if there is nothing matching that
[14:47:59 CET] <bmcginty> JEEB: I think I have to specify -map 0 because I basically want to copy everything except video streams, and I want to make sure there's at least one audio track.
[14:49:19 CET] <JEEB> right, that is non-specific enough to not fail unless you have zero streams :P
[16:40:26 CET] <kingmanor> is there a way to limit ffmpeg cpu usage without running it in a vm?
[16:41:10 CET] <JEEB> depends on your OS
[16:41:25 CET] <JEEB> linux for example has cgroups and both linux and windows has pinning to specific cores
[16:48:25 CET] <kingmanor> i have a windows box rebooting in the middle of a long ffmpeg transcode.  i tried it running the same job in a linux vm with 94% cpu entitlement and still happening.
[16:49:01 CET] <durandal_1707> kingmanor: post full ffmpeg command?
[16:49:49 CET] <kingmanor> ffmpeg -loglevel verbose -i gb_wintergames_2018.mp4 -c:v libx265 -c:a copy -map_metadata -1 -report gb_wintergames_2018.mkv
[16:50:00 CET] <kingmanor> its a 2 hour high bitrate 1080 mp4 file
[16:50:08 CET] <kingmanor> converting to hevc
[16:50:26 CET] <kingmanor> using latest zeranoe windows build
[16:50:30 CET] <durandal_1707> how much RAM you have?
[16:50:38 CET] <kingmanor> 8gb
[16:51:12 CET] <durandal_1707> wait, only vm reboots?
[16:51:21 CET] <kingmanor> no the whole box reboots
[16:51:27 CET] <durandal_1707> that that is hw issue
[16:52:07 CET] <kingmanor> yes i am asking if there is a way to limit cpu without running in a vm that is capped at less mhz
[18:04:00 CET] <ultrav1olet> I have a number of photos with varying sizing and aspect ratios and I want to get a video from them however I'm not sure what to do
[18:04:19 CET] <ultrav1olet> I've resized them so that their maximum dimensions are either 1920 or 1080
[18:04:35 CET] <ultrav1olet> However when I try to encode them, ffmpeg resizes them and makes them all full screen
[18:04:50 CET] <ultrav1olet> which breaks the aspect ratio completely and makes them look horrible
[18:05:13 CET] <ultrav1olet> I've tried all the examples on the net and none of them work
[18:05:44 CET] <ultrav1olet> my first image is black 1920x1080 or otherwise ffmpeg f*cks everything up
[18:06:11 CET] <ultrav1olet> I now need to concatenate images without resizing them at all
[18:09:12 CET] <ultrav1olet> Tried this https://stackoverflow.com/questions/44634765/ffmpeg-aspect-ratio-of-image-in-a-slideshow https://stackoverflow.com/questions/38937136/ffmpeg-different-sized-images-to-gif-while-preserving-original-aspect-ratio https://superuser.com/questions/547296/resizing-videos-with-ffmpeg-avconv-to-fit-into-static-sized-player/1136305#1136305
[18:09:16 CET] <ultrav1olet> nothing works
[18:09:20 CET] <ultrav1olet> damn it
[18:57:03 CET] <kepstin> if you're trying to put photos into a 16:9 1080p video preserving aspect ratio, then you're going to have to pad them (ffmpeg 'pad' filter) to add bars to the sides.
[18:58:09 CET] <kepstin> something like 'pad=1920:1080:(ow-iw)/2:(oh-ih)/2' should do the trick, assuming the pictures have already been resized
[18:58:25 CET] <kepstin> er, wait, they already left
[18:58:28 CET] <kepstin> ... :/
[21:24:38 CET] <docmax> whats the command line to copy video to udp://0.0.0.0:1234 AND play audio locally?
[21:36:45 CET] <docmax> anyone?
[00:00:00 CET] --- Wed Dec 26 2018