[Ffmpeg-devel-irc] ffmpeg.log.20171021

burek burek021 at gmail.com
Sun Oct 22 03:05:01 EEST 2017


[03:52:03 CEST] <Johnjay> i can tell you it's a royal pain the but butt to operate on directories in windows with ffmpeg
[03:52:34 CEST] <Johnjay> some way to apply the command to all files in a directory would be cool. Or like files matching a wildcard
[03:53:16 CEST] <Johnjay> maybe interpret ffmpeg -i "*.mp4" as a valid input file
[04:57:52 CEST] <jcjordyn120> Doesn't the shell interpret wildcards?
[05:06:05 CEST] <Johnjay> on windows it only interprets * and ?
[05:06:26 CEST] <Johnjay> for example if you want to loop over only .m4a and .webm files you have to write the for loop twice
[05:06:55 CEST] <Johnjay> there might be a way to do it in powershell, dunno
[05:15:49 CEST] <jcjordyn120> Hmm
[05:16:03 CEST] <jcjordyn120> That's solved with a better shell, or two for loops.
[05:24:32 CEST] <Johnjay> jcjordyn120: yeah well good luck with that. let me know when you find one that comes with the OS
[05:25:14 CEST] <jcjordyn120> Windows 10 has WSL
[05:25:45 CEST] <jcjordyn120> Even then if you're using windows can't you afford a better shell?
[05:27:57 CEST] <Johnjay> well yes i can. but for perspective I didn't know msys2 was able to compile ffmpeg until a few weeks ago
[05:28:22 CEST] <Johnjay> I didn't know about WSL until a few days ago either.
[05:28:38 CEST] <Johnjay> The average person is not going to get that far trying to use ffmpeg to encode a video or two
[05:32:42 CEST] <jcjordyn120> We're talking about the command line interface to ffmpeg.. right?
[05:33:14 CEST] <Johnjay> i don't know. does it have a GUI interface?
[05:34:34 CEST] <jcjordyn120> No clue, most of my uses of ffmpeg are from the cli.
[05:34:41 CEST] <jcjordyn120> Or another program calling it
[06:54:57 CEST] <mozzarella> guys
[06:55:56 CEST] <mozzarella> how do I convert a video to h265
[07:33:55 CEST] <Johnjay> ffmpeg -i video.mp4 -c x265 output.mp4?
[07:34:57 CEST] <Johnjay> well apparently that's not a valid encoder
[07:46:28 CEST] <Johnjay> hmm so using -c hevc doesn't work
[07:46:34 CEST] <Johnjay> but using -c:v hevc does work
[08:06:25 CEST] <jcjordyn120> Makes sense
[09:42:12 CEST] <Toba> hey... so I'm using multiple drawtexts to create titles that are center justified
[09:43:34 CEST] <Toba> I'm using text_h in expressions to do multi line spacing, since I intend to make my font size settable on my titles generator
[09:43:49 CEST] <Toba> https://stackoverflow.com/a/22719247 - I'm using a formula similar to "Multiple drawtext instances
[09:43:55 CEST] <Toba> " from this stack overflow answer
[09:44:04 CEST] <Toba> text_h though, refers to the height of the current drawtext
[09:44:42 CEST] <Toba> so my lines of text are a little jumbled up vertically, since some of the lines have tall glyphs in them and some don't
[09:45:20 CEST] <Toba> Any ideas about how to center justify a paragraph of text while avoiding this issue?
[12:28:02 CEST] <Spioune> Hi everyone
[12:28:06 CEST] <Spioune> can someone help me?
[12:31:37 CEST] <Spioune> I get "ERROR: OMX_Core.h header not found" when I do "./configure --enable-gpl --enable-nonfree --enable-mmal --enable-omx --enable-omx-rpi"
[12:31:48 CEST] <Spioune> on a raspberry pi 3
[12:55:40 CEST] <Spioune> alright
[12:57:14 CEST] <Spioune> people?
[13:14:25 CEST] <furq> Spioune: do you have that header in /opt/vc/include/IL
[13:14:43 CEST] <furq> if not then you probably need to run rpi-update
[13:14:52 CEST] <furq> bye
[17:30:52 CEST] <FurretUber> Hi, I am trying to build ffmpeg in Xubuntu 17.10, but I'm having trouble with opencv. The libopencv-dev is installed but apparently the tests are having errors
[17:31:10 CEST] <JEEB> see ffbuild/config.log
[17:31:23 CEST] <JEEB> (you can also pastebin it for easier visibility)
[17:31:26 CEST] <JEEB> and link here
[17:31:44 CEST] <FurretUber> Here is it: https://pastebin.com/ud4G1hGG
[17:32:03 CEST] <FurretUber> It's the snapshot from today
[17:32:56 CEST] <JEEB> seems like the pkg-config file doesn't contain all things to link against
[17:33:04 CEST] <JEEB> you can see those undefined references
[17:33:12 CEST] <JEEB> or the pkg-config file has them in the wrong order or so?
[17:33:36 CEST] <JEEB> because there's a use_pkg_config check for it
[17:33:53 CEST] <JEEB> then it falls back to a manual one and that fails too, unsurprisingly
[17:34:33 CEST] <JEEB> if you can find out which library contains cvRound you can start piecing together what's missing
[17:34:48 CEST] <FurretUber> The system was upgraded from 17.04 so the packages installed should be the same (this is not 100% accurate, as something may have been removed)
[17:35:09 CEST] <JEEB> not same, but newer versions usually
[17:35:55 CEST] <JEEB> anyways, as I said. two alternatives: 1) the pc file doesn't contain what is required to link against it or 2) we are missing a library that we're supposed to also look at through pkg-config
[17:36:03 CEST] <JEEB> in this newer version you got with 17.10
[17:36:57 CEST] <JEEB> seems like opencv got updated from 2.4.9 to 3.1.0
[17:37:00 CEST] <JEEB> not a small jump
[17:37:41 CEST] <FurretUber> I've found a GitHub issue page: https://github.com/opencv/opencv/issues/8438
[17:37:51 CEST] <FurretUber> It says the reference is in a different file now
[17:38:11 CEST] <FurretUber> And C++ should be used, and not C, if I understood correctly
[17:38:36 CEST] <JEEB> ok, that just means that they're dropping support for the C API that we're using
[17:39:00 CEST] <JEEB> FurretUber: you're out of luck then
[17:39:11 CEST] <JEEB> blame the upstream :)
[17:40:18 CEST] <FurretUber> Should I report this somewhere as a bug in ffmpeg then?
[17:40:27 CEST] <JEEB> opencv stuff (which I'm not even sure what it does if anything) in FFmpeg was someone's research thing, that got in.
[17:40:36 CEST] <JEEB> and this is upstream (opencv) breaking compatibility with that code
[17:40:50 CEST] <JEEB> so, uh, I think unless you find someone willing to rewrite this
[17:41:02 CEST] <JEEB> it will get removed eventually
[17:42:35 CEST] <JEEB> FurretUber: you can make an issue like "OpenCV components require rewrite in C++ due to OpenCV upstream changes"
[17:43:03 CEST] <JEEB> but since nobody seems to care about OpenCV (as far as I know), and the original author has since moved onto other research (most likely), I think it's not likely to get fixed
[17:44:05 CEST] <JEEB> FurretUber: do you actually need the opencv stuff and thus know WTF it does? :D
[17:44:18 CEST] <JEEB> or is this you just following some random compilation guide :P
[17:44:25 CEST] <FurretUber> I am using this huge configure command from the Ubuntu's ffmpeg build plus some additional options I needed. From my tries yesterday, opencv is used for the spice protocol, so without it it could break virtual machines (they would boot but it would not be possible to see the graphics.
[17:44:41 CEST] <JEEB> uhh
[17:44:50 CEST] <JEEB> why would it have anything to do with VMs?
[17:45:04 CEST] <JEEB> also FFmpeg doesn't even support that
[17:45:17 CEST] <FurretUber> This I don't know, but it's what apt says if I try to purge opencv
[17:45:21 CEST] <JEEB> if you just want to build your own copy of FFmpeg, just don't enable opencv
[17:45:29 CEST] <JEEB> remove --enable-opencv
[17:45:53 CEST] <JEEB> and you can remove the libopencv-dev package if you never expect to be building something with opencv
[17:45:58 CEST] <JEEB> by yourself that is
[17:46:06 CEST] <JEEB> you don't need to remove opencv altogether you know :P
[17:46:18 CEST] <JEEB> you're specifically forcing opencv to be enabled and thus it fails during configure
[17:46:23 CEST] <JEEB> (of FFmpeg)
[17:49:46 CEST] <FurretUber> The Ubuntu's default config has opencv enabled, as I wanted to replace the Ubuntu's default by the version I built, I suppose it must have everything Ubuntu's configuration has, at least. If I try without opencv it works, but then I have to keep a parallel install
[17:50:41 CEST] <FurretUber> Where should I make an issue?
[17:52:44 CEST] <JEEB> uhh, I'm pretty sure ubuntu had to disable it
[17:52:47 CEST] <JEEB> or they patched it
[17:54:21 CEST] <JEEB> ok, their libavfilter seems to still link against opencv-core and imgproc
[17:54:25 CEST] <JEEB> so they probably patched it
[17:54:39 CEST] <FurretUber> When using their ffmpeg (with no options) it prints "WARNING: library configuration mismatch". They had some trouble, apparently, but still have --enable-libopencv
[17:55:06 CEST] <JEEB> no, that just means that something you built is getting grabbed as libraries go
[19:41:56 CEST] <AEP197_2> oi
[19:51:51 CEST] <kiroma> Hey, I have issues when compiling ffmpeg with nvecn
[19:51:54 CEST] <kiroma> *nvenc
[19:52:09 CEST] <kiroma> "ERROR: nvenc requested, but not all dependencies are satisfied: cuda"
[19:52:18 CEST] <kiroma> Even though --enable-cuda is specified.
[19:54:40 CEST] <kiroma> Ah, wait, it's not finding cuda
[19:58:21 CEST] <dystopia_> im setting "-preset slow" but in my mediainfo i see "me=hex" instead of "me=umh"
[19:58:24 CEST] <dystopia_> anyone know why?
[20:05:12 CEST] <furq> what's the full command
[20:05:44 CEST] <dystopia_> ffmpeg -t 10 -y -i in.ts -sws_flags spline -vf yadif=1:0,scale=720:-4,setsar=1:1 -c:v libx264 -preset slow -profile:v high -level 3.1 -crf 24 -r 50 -x264opts force-cfr=1:colormatrix=bt709 -sn -acodec copy out.mkv
[20:07:14 CEST] <furq> weird
[20:07:25 CEST] <furq> i just checked and i get the same thing
[20:07:29 CEST] <furq> maybe they changed the presets recently
[20:08:10 CEST] <furq> either that or this preset reference site has always been wrong
[20:08:26 CEST] <dystopia_> https://pastebin.com/drrtf3XM
[20:08:27 CEST] <kiroma> --arch=native breaks configuration
[20:08:35 CEST] <dystopia_> :(
[20:09:00 CEST] <furq> i'm pretty sure i remember slow being umh
[20:09:02 CEST] <furq> so i guess it was changed
[20:16:34 CEST] <kiroma> What gcc compilers are supported by cuda?
[20:16:35 CEST] <dystopia_> so is there some way to manually set me=umh?
[20:18:17 CEST] <DHE> dystopia_: you can use -x264opts to specify options manually
[20:18:18 CEST] <CoreX> me=hex has been default for months now under preset slow
[20:18:40 CEST] <dystopia_> default in x264.exe also?
[20:18:44 CEST] <CoreX> yes
[20:18:50 CEST] <dystopia_> ok :)
[20:19:10 CEST] <dystopia_> thank you corex/furq or the info
[20:19:15 CEST] <dystopia_> for the info*
[20:37:09 CEST] <kiroma> Is there such thing as a libffmpeg.so
[20:37:10 CEST] <kiroma> ?
[20:46:08 CEST] <DHE> it's a collection of libraries such as libavcodec.so, libavformat.so, etc
[20:53:54 CEST] <kiroma> How can I get it? What config flag does it need?
[20:57:05 CEST] <thebombzen> the libraries are built by default
[20:57:25 CEST] <DHE> if you want the .so files, --enable-shared but the defaults are static-only
[20:57:42 CEST] <thebombzen> the headers and libraries also come with the ffmpeg installed by your package manager (probably) so you don't necessarily need to build it yourself
[20:58:13 CEST] <thebombzen> depending on your system, you might need to install ffmpeg-devel, ffmpeg-dev, etc.
[21:02:58 CEST] <kiroma> I compile my ffmpeg with --enable-shared but I never got that library.
[21:03:36 CEST] <kiroma> There's all libs from libav, but I've never seen libffmpeg.so being compiled.
[21:10:09 CEST] <thebombzen> there is no "libffmpeg.so"
[21:10:16 CEST] <thebombzen> the name of the libraries is libavcodec, libavformat, etc.
[21:10:38 CEST] <thebombzen> there's more than one library. the functionality of the FFmpeg project is fragmented into several libraries because they do different things and not all applications need all libraries
[21:11:27 CEST] <thebombzen> the library names of libavcodec, libavformat, libswscale, etc. predate the existence of the Libav fork. The Libav fork of FFmpeg project is named thus to intentionally confuse you
[21:11:49 CEST] <kiroma> Then what the hell is the thing that's in Discord's share folder?
[21:12:01 CEST] <thebombzen> huh?
[21:12:58 CEST] <kiroma> There is a file in /usr/share/discord that's called "libffmpeg.so" and nobody knows what it is.
[21:13:31 CEST] <kiroma> I tried searching it up but nothing came up.
[21:13:35 CEST] <thebombzen> DiscordApp has its own custom build of ffmpeg
[21:14:17 CEST] <thebombzen> the Discord developers basically smashed it all together internally. many non-FOSS pieces of software don't like using the system libraries for some weirdass reason.
[21:14:33 CEST] <kiroma> Ah, I see.
[21:15:09 CEST] <thebombzen> you, however, should use the standard method of linking
[22:06:49 CEST] <srini> Hello
[22:08:10 CEST] <srini> i am looking to segment the static video files from youtube into mpegts files
[22:10:01 CEST] <DHE> there's a segment driver. you might also be able to use the HLS driver since it outputs to mpegts segments by default anyways
[22:10:01 CEST] <srini> any idea how can i use byte ranges and produce the ts files, something similar to hls
[22:10:55 CEST] <DHE> mpegts is special in that it's a streaming format. it's designed so that you can join it at any point (even non-byte boundaries) and playback with no seek capability. by contrast youtube uses mp4 and webm
[22:11:43 CEST] <srini> DHE: Thanks, thats right
[22:12:01 CEST] <DHE> for 10 second segments (and abusing the HLS muxer to do the heavy lifting), something like: ffmpeg -i input.mp4 -c copy -f hls -hls_time 10 output.m3u8
[22:12:20 CEST] <DHE> oh, add -hls_list_size 0
[22:18:04 CEST] <srini> DHE: But this needs the video to be downloaded, i am looking to connect to the base url from the mpd.xml and then download the segments and create the ts files
[22:18:51 CEST] <DHE> ffmpeg will accept URLs for the input(s). even with SSL if it was built with SSL support
[22:31:02 CEST] <srini> DHE: Thanks appreciate your response
[23:57:13 CEST] <kerio> DHE: hold on, non-byte boundaries?
[23:57:19 CEST] <kerio> how does that even work
[23:58:09 CEST] <DHE> there's a sync byte every 188 bytes. in theory it's possible
[23:58:36 CEST] <DHE> remember mpegts is what's carried over the air. your TV can tune into it at any instant
[23:59:17 CEST] <kerio> fair enough
[00:00:00 CEST] --- Sun Oct 22 2017


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