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Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
Configuration spécifique d’Apache
4 février 2011, parModules spécifiques
Pour la configuration d’Apache, il est conseillé d’activer certains modules non spécifiques à MediaSPIP, mais permettant d’améliorer les performances : mod_deflate et mod_headers pour compresser automatiquement via Apache les pages. Cf ce tutoriel ; mode_expires pour gérer correctement l’expiration des hits. Cf ce tutoriel ;
Il est également conseillé d’ajouter la prise en charge par apache du mime-type pour les fichiers WebM comme indiqué dans ce tutoriel.
Création d’un (...)
Sur d’autres sites (4144)
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MPEG Dash output generated by FFMPEG not working
8 janvier 2019, par Anto JoyI created a dash output sample_video.mpd file using ffmpeg, but when I tried to play it using dash js the video was just loading and nothing else.
Below is the generated mpd file<?xml version="1.0" encoding="utf-8"?>
<mpd xmlns="urn:mpeg:dash:schema:mpd:2011" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" mediapresentationduration="PT1M2.3S" minbuffertime="PT20.0S">
<programinformation>
</programinformation>
<period start="PT0.0S">
<adaptationset contenttype="video" segmentalignment="true" bitstreamswitching="true" lang="und">
<representation mimetype="video/mp4" codecs="avc1.640015" bandwidth="255520" width="426" height="240" framerate="24/1">
<segmenttemplate timescale="12288" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="198656" d="69120"></s>
<s d="75264"></s>
<s d="174592"></s>
<s d="122880"></s>
<s d="125440"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001e" bandwidth="726596" width="854" height="480" framerate="24/1">
<segmenttemplate timescale="12288" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="198656" d="69120"></s>
<s d="75264"></s>
<s d="174592"></s>
<s d="122880"></s>
<s d="125440"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="video/mp4" codecs="avc1.64001f" bandwidth="1433314" width="1280" height="720" framerate="24/1">
<segmenttemplate timescale="12288" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="198656" d="69120"></s>
<s d="75264"></s>
<s d="174592"></s>
<s d="122880"></s>
<s d="125440"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
<adaptationset contenttype="audio" segmentalignment="true" bitstreamswitching="true" lang="und">
<representation mimetype="audio/mp4" codecs="mp4a.40.2" bandwidth="341000" audiosamplingrate="48000">
<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="6"></audiochannelconfiguration>
<segmenttemplate timescale="48000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="772096" d="270336"></s>
<s d="293888"></s>
<s d="681984"></s>
<s d="480256"></s>
<s d="492544"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="audio/mp4" codecs="mp4a.40.2" bandwidth="341000" audiosamplingrate="48000">
<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="6"></audiochannelconfiguration>
<segmenttemplate timescale="48000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="772096" d="270336"></s>
<s d="293888"></s>
<s d="681984"></s>
<s d="480256"></s>
<s d="492544"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
<representation mimetype="audio/mp4" codecs="mp4a.40.2" bandwidth="341000" audiosamplingrate="48000">
<audiochannelconfiguration schemeiduri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="6"></audiochannelconfiguration>
<segmenttemplate timescale="48000" initialization="init-stream$RepresentationID$.m4s" media="chunk-stream$RepresentationID$-$Number%05d$.m4s" startnumber="3">
<segmenttimeline>
<s t="772096" d="270336"></s>
<s d="293888"></s>
<s d="681984"></s>
<s d="480256"></s>
<s d="492544"></s>
</segmenttimeline>
</segmenttemplate>
</representation>
</adaptationset>
</period>
</mpd>The following is the ffmpeg command that i used to generate multi bitrate video
ffmpeg -y -i sample_video.mp4 ^
-c:v libx264 -x264opts "keyint=24:min-keyint=24:no-scenecut" -r 24 ^
-c:a aac -b:a 128k ^
-bf 1 -b_strategy 0 -sc_threshold 0 -pix_fmt yuv420p ^
-map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 ^
-b:v:0 250k -filter:v:0 "scale=-2:240" -profile:v:0 baseline ^
-b:v:1 750k -filter:v:1 "scale=-2:480" -profile:v:1 main ^
-b:v:2 1500k -filter:v:2 "scale=-2:720" -profile:v:2 high ^
sample_dash.mp4and to generate the mpd file
ffmpeg -y -re -i sample_dash.mp4 ^
-map 0 ^
-use_timeline 1 -use_template 1 -window_size 5 -adaptation_sets
"id=0,streams=v id=1,streams=a" ^
-f dash sample_video.mpdAlso I saw in the chrome network tab that only init-stream4.m4s and init-stream5.m4s was called.
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make ffmpeg chose Nvidia CUDA over Intel QSV (Windows 10 with two video adapters)
3 avril 2024, par Bart LedermanI just set up a 'new' PC with built-in Intel video and an Nvida card : mostly to speed up video processing with ffmpeg and other programs. At first the built-in Intel was disabled, running only the Nvidia card. ffmpeg worked as expected, the CPU could be used for decoding and encoding.


However : VirtualDub, a program I use frequently, has a problem with Nvidia cards (at least on Windows 10). The display gets screwed up, previews don't work, and all sorts of other problems occur. I tried all of the various discussion boards, and nobody has a good solution. (The problem is apparently split between VirtualDub and Nvidia, as all other programs such as VideoLan, Avidemux, HandBrake, OBS studio, etc, all appear to work fine.)


So I re-enabled the on-board Intel adapter, and made that my primary and only video with a monitor. The Nvidia card is still there, but with no monitor attached. I really only need it for hardware acceleration.


HandBrake and OBS Studio found the card and used it with no problem.


However, my batch file that specified cuda for both decoding and encoding failed to run. The ffmpeg command that includes -hwaccel cuda resulted in :


[h264 @ 000002783beaa700] Hardware is lacking required capabilities 
[h264 @ 000002783beaa700] Failed setup for format cuda: hwaccel initialisation returned error.



I also tried -hwaccel nvenc, which is rejected. It's apparently not a synonym in this version of ffmpeg :


ffmpeg version 4.3.1-2021-01-01-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers built with gcc 10.2.0 (Rev5, Built by MSYS2 project) configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-lzma --enable-libsnappy --enable-zlib --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libzvbi --enable-librav1e --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint libavutil 56. 51.100 / 56. 51.100 libavcodec 58. 91.100 / 58. 91.100 libavformat 58. 45.100 / 58. 45.100 libavdevice 58. 10.100 / 58. 10.100 libavfilter 7. 85.100 / 7. 85.100 libswscale 5. 7.100 / 5. 7.100 libswresample 3. 7.100 / 3. 7.100 libpostproc 55. 7.100 / 55. 7.100



When I use QSV acceleration on my other PC I have to do this :


-init_hw_device qsv=qsv -hwaccel qsv



so I tried


-init_hw_device cuda=cuda -hwaccel cuda



but that didn't work either.


I've seen comments about the ability to select the GPU if there is more than one board installed, using the -gpu option. However, when I try to use -gpu 0 or -gpu 1 I get :


Codec AVOption gpu (Selects which NVENC capable GPU to use. First GPU is 0, second is 1, and so on.) specified for input file #0 (xxx.avi) is not a decoding option.


I looked at :


https://github.com/FFmpeg/FFmpeg/commit/527a1e213167123d24d014bc0b956ef43d9d6542


to get more information on -init_hw_device, but I'm sorry to say that what's on that page makes no sense to me at all. There are no examples, and no explanation of how to actually select a device.


I looked at :


https://docs.nvidia.com/video-technologies/video-codec-sdk/ffmpeg-with-nvidia-gpu/


which has an 'example' of -init_hw_device, and I did a cut and paste of what they had there to my batch file, but it was rejected.


I also looked at :


How to to burn subtitles based image on video using ’overlay_cuda’, ffmpeg video filter


which has two examples of how to initialize a cuda device, and they don't work for me either. -init_hw_device cuda=cuda is accepted without error, but then -hwaccel cuda still fails. Trying to use the hw accelerated filter scale_cuda also fails.


So how do I get the Nvidia card to decode video when it's not the only graphics adapter ? I was able to decode video when only the Nvidia card was active, there "must" be a way to get to it now. I just need to know how to tell ffmpeg to use the card that is there. Since it has no problem finding the card for encoding, shouldn't it also still be able to find the card for decoding and filters ? Or am I really the first person ever to have both Intel and Nvidia graphics adapters working on my system and trying to use ffmpeg with hardware acceleration ?


=====================


Latest update.


I had tried the examples on the Nvidia FFmpeg transcoding guide web page, and as mentioned previously I still got errors. I did a cut and paste from that web page to my command window, and ffmpeg still did not find the correct graphics adapter.


However, I do have a work-around. I don't particularly like it, but it works.


First : Windows (10) does not understand the concept of a graphics adapter that doesn't have a monitor attached to it. Even though graphics processors (specifically Nvidia) are available without the actual video output and are used in supercomputers and elsewhere to do high speed stream processing, Windows will not let you access the card settings if there is no monitor attached. The Nvidia control center also will not allow you to access any of the card's settings, and you can't set processor affinity.


So I connected a second monitor, and set up the Nvidia card as the primary.


Now ffmpeg -hwaccel cuda works the first time. The command I was using before :


ffmpeg -hide_banner -hwaccel cuda -i "input.avi" -c:a copy -ac 1 -c:v h264_nvenc -preset hq -movflags faststart -qp 30 "output.mp4"



Was failing because it couldn't find the Nvidia adapter. This command now works correctly the first time and uses hardware acceleration for both decode and encode. (The audio portion is irrelevant, if I also re-encode the audio the results are the same.)


With scaling, the command was like this :


ffmpeg -hide_banner -hwaccel cuda -i "input.avi" -c:a copy -ac 1 -c:v h264_nvenc -preset hq -vf "scale=640:480" -movflags faststart -qp 30 "output.mp4"



This works. However :


ffmpeg -hide_banner -hwaccel cuda -i "input.avi" -c:a copy -ac 1 -c:v h264_nvenc -preset hq -vf "scale_cuda=640:480" -movflags faststart -qp 30 "output.mp4



Fails with


Impossible to convert between the formats supported by the filter 'graph 0 input from stream 0:0' and the filter 'auto_scaler_0'
Error reinitializing filters!
Failed to inject frame into filter network: Function not implemented
Error while processing the decoded data for stream #0:0



I was able to get around this, by rearranging things in what seems to be to be an unnecessarily convoluted syntax.


ffmpeg -hide_banner -hwaccel cuvid -hwaccel_output_format cuda -i "input.avi" -c:a aac -b:a 192k -ar 48000 -vf "scale_cuda=856:480" -c:v h264_nvenc -preset hq -movflags faststart -qp 26 "output.mp4"



Having to specify the output format twice seems weird, but Task Manager shows near 100% Video Decode activity, and the time it takes to do this indicates to me that the scale_cuda filter is being used.


I don't particularly like having to use a second monitor (If VirtualDub worked properly I probably wouldn't have to), but I'm willing to live with it. It appears that if you have two different video cards and you want to use hardware acceleration on one of them it has to be the primary.


I haven't tested if Intel QSV is still accessible, nor have I tried switching the order of the graphics adapters back to completely verify the source of the problem, and I'm not really planning to do so (unless some of you think that would be useful). I get the definite impression that few people, if any, have tried to get both an Nvidia and an Intel adapter to provide hardware video acceleration on the same system. I will try to access QSV to see if using both accelerators is an improvement.


I can live with the weird command line to get the cuda filters to work, but if anyone knows a better way to do it I think it would be helpful to post it here for future reference if anyone else runs into a similar problem. None of the examples of using cuda accelerated filters that I've found on any of the many web sites I've read worked exactly as given.


==================


The good news :


It's possible to use both Nvidia and QSV hardware in at least some cases.


This command works :


ffmpeg -hide_banner -hwaccel dxva2 -i "input.avi" -c:a copy ^
 -c:v h264_qsv -vf "crop=1920:1044:0:0" -preset veryfast -profile:v high -level 4.1 -qp 22 "output.mp4"



Task Manager says Nvidia is decoding the input, and GPU-Z says Intel is also active, so it must be doing the encoding.


The bad news : I can't figure out a way to use both a CUDA filter and a standard filter in the same process.


This does not work :


ffmpeg -hide_banner -hwaccel cuvid -hwaccel_output_format cuda -i "input.avi" -c:a aac -b:a 192k -ar 48000 -vf "scale_cuda=856:480,crop=1280:696:0:24" -c:v h264_nvenc -preset hq -movflags faststart -qp 30 "output.mp4"



Reversing the order of scale_cuda and crop (with appropriate adjustments to the numbers) also does not work. There are errors about not being able to transfer the processing stream.


I will try the changes in the latest comment, but I think I may have tried it before and something didn't work. But I will check again.


In my web searches I have not found an example of 'mixed' filters.


I did see "-crop" and "-resize" on the Nvidia ffmpeg trancode web page similar to this :


–crop 0x36x0x0 –resize 1280x696



Once again, I did a cut and paste from the Nvidia web page to my command window and it didn't work. If there is a way to invoke the Nvidia command for these options that has been tested and found to actually work I would really like to see it.


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Trying to scale a webm video to 50% of its resolution using FFMPEG but keep getting an error (video has transparency btw)
6 février 2021, par DistantDigitI'm trying to scale down a webm video with transparency using this line of commands (based off of an answer in this stackoverflow question @ How to keep transparency when scale webm file with ffmpeg) :


ffmpeg -c:v libvpx -i in.webm -c:v libvpx -vf scale=400:416 -auto-alt-ref 0 out.webm


but I keep getting errors (for example) :


[libvpx @ 00000128eb6123c0] Invalid sync code 310042.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
Cannot determine format of input stream 0:0 after EOF



Full log (I've removed a ton of the same exact message with "..."'s) :


ffmpeg version 2021-02-02-git-2367affc2c-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers
 built with gcc 10.2.0 (Rev6, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-lzma --enable-libsnappy --enable-zlib --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libglslang --enable-vulkan --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
 libavutil 56. 64.100 / 56. 64.100
 libavcodec 58.120.100 / 58.120.100
 libavformat 58. 65.101 / 58. 65.101
 libavdevice 58. 11.103 / 58. 11.103
 libavfilter 7.101.100 / 7.101.100
 libswscale 5. 8.100 / 5. 8.100
 libswresample 3. 8.100 / 3. 8.100
 libpostproc 55. 8.100 / 55. 8.100
[libvpx @ 00000128eb6123c0] v1.9.0-146-gebb5ffc1d
[libvpx @ 00000128eb6123c0] Invalid sync code 310042.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
[libvpx @ 00000128eb6123c0] Invalid sync code 007a49.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
[libvpx @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
...
...
...
[libvpx @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
[libvpx @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
[libvpx @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb6123c0] Failed to decode frame: Bitstream not supported by this decoder
[libvpx @ 00000128eb6123c0] Invalid sync code 01f096.
[matroska,webm @ 00000128eb60f040] decoding for stream 0 failed
[matroska,webm @ 00000128eb60f040] Could not find codec parameters for stream 0 (Video: vp8 (libvpx), none(progressive), 800x832): unspecified pixel format
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, matroska,webm, from 'in.webm':
 Metadata:
 encoder : libwebm-0.2.1.0
 creation_time : 2017-12-02T12:06:12.000000Z
 Duration: 00:00:10.00, start: 0.000000, bitrate: 2592 kb/s
 Stream #0:0(eng): Video: vp8, none(progressive), 800x832, SAR 1:1 DAR 25:26, 30 fps, 30 tbr, 1k tbn, 1k tbc (default)
 Metadata:
 alpha_mode : 1
[libvpx @ 00000128eb612a40] v1.9.0-146-gebb5ffc1d
Stream mapping:
 Stream #0:0 -> #0:0 (vp8 (libvpx) -> vp8 (libvpx))
Press [q] to stop, [?] for help
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
Error while decoding stream #0:0: Invalid data found when processing input
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
Error while decoding stream #0:0: Invalid data found when processing input
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
...
...
...
Error while decoding stream #0:0: Invalid data found when processing input
[NULL @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
Error while decoding stream #0:0: Invalid data found when processing input
[NULL @ 00000128eb6123c0] Invalid sync code 01f096.
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
Error while decoding stream #0:0: Invalid data found when processing input
[NULL @ 00000128eb6123c0] Invalid sync code 009c96.
[libvpx @ 00000128eb612a40] Failed to decode frame: Bitstream not supported by this decoder
Error while decoding stream #0:0: Invalid data found when processing input
Cannot determine format of input stream 0:0 after EOF
Error marking filters as finished
Conversion failed!



Log of
ffmpeg -i input.webm
:

ffmpeg version 2021-02-02-git-2367affc2c-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers
 built with gcc 10.2.0 (Rev6, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-lzma --enable-libsnappy --enable-zlib --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libglslang --enable-vulkan --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
 libavutil 56. 64.100 / 56. 64.100
 libavcodec 58.120.100 / 58.120.100
 libavformat 58. 65.101 / 58. 65.101
 libavdevice 58. 11.103 / 58. 11.103
 libavfilter 7.101.100 / 7.101.100
 libswscale 5. 8.100 / 5. 8.100
 libswresample 3. 8.100 / 3. 8.100
 libpostproc 55. 8.100 / 55. 8.100
Input #0, matroska,webm, from 'input.webm':
 Metadata:
 encoder : libwebm-0.2.1.0
 creation_time : 2017-12-02T12:06:12.000000Z
 Duration: 00:00:10.00, start: 0.000000, bitrate: 2592 kb/s
 Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv), 800x832, SAR 1:1 DAR 25:26, 30 fps, 30 tbr, 1k tbn, 1k tbc (default)
 Metadata:
 alpha_mode : 1
At least one output file must be specified