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MediaSPIP Simple : futur thème graphique par défaut ?
26 septembre 2013, par
Mis à jour : Octobre 2013
Langue : français
Type : Video
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avec chosen
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Mis à jour : Septembre 2013
Langue : français
Type : Image
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sans chosen
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Mis à jour : Septembre 2013
Langue : français
Type : Image
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config chosen
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Mis à jour : Septembre 2013
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SPIP - plugins - embed code - Exemple
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Mis à jour : Septembre 2013
Langue : français
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GetID3 - Bloc informations de fichiers
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Mis à jour : Mai 2013
Langue : français
Type : Image
Autres articles (3)
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Menus personnalisés
14 novembre 2010, parMediaSPIP utilise le plugin Menus pour gérer plusieurs menus configurables pour la navigation.
Cela permet de laisser aux administrateurs de canaux la possibilité de configurer finement ces menus.
Menus créés à l’initialisation du site
Par défaut trois menus sont créés automatiquement à l’initialisation du site : Le menu principal ; Identifiant : barrenav ; Ce menu s’insère en général en haut de la page après le bloc d’entête, son identifiant le rend compatible avec les squelettes basés sur Zpip ; (...) -
Selection of projects using MediaSPIP
2 mai 2011, parThe examples below are representative elements of MediaSPIP specific uses for specific projects.
MediaSPIP farm @ Infini
The non profit organizationInfini develops hospitality activities, internet access point, training, realizing innovative projects in the field of information and communication technologies and Communication, and hosting of websites. It plays a unique and prominent role in the Brest (France) area, at the national level, among the half-dozen such association. Its members (...) -
Mise à disposition des fichiers
14 avril 2011, parPar défaut, lors de son initialisation, MediaSPIP ne permet pas aux visiteurs de télécharger les fichiers qu’ils soient originaux ou le résultat de leur transformation ou encodage. Il permet uniquement de les visualiser.
Cependant, il est possible et facile d’autoriser les visiteurs à avoir accès à ces documents et ce sous différentes formes.
Tout cela se passe dans la page de configuration du squelette. Il vous faut aller dans l’espace d’administration du canal, et choisir dans la navigation (...)
Sur d’autres sites (3510)
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Why does ffmpeg hang when I try to use my webcam's raw stream ?
25 septembre 2021, par Sam MiddletonI'm trying to use ffmpeg to record videos from a webcam.


When I run
ffmpeg -f v4l2 -list_formats all -i /dev/video0
I get the following output :

ffmpeg version 4.2.4-1ubuntu0.1 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 9 (Ubuntu 9.3.0-10ubuntu2)
 configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
 WARNING: library configuration mismatch
 avcodec configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libaribb24 --enable-liblensfun --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libavresample 4. 0. 0 / 4. 0. 0
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
[video4linux2,v4l2 @ 0x55f3fbd816c0] Compressed: mjpeg : Motion-JPEG : 1920x1080
[video4linux2,v4l2 @ 0x55f3fbd816c0] Raw : yuyv422 : YUYV 4:2:2 : 1920x1080
/dev/video0: Immediate exit requested



I can record by using the command
ffmpeg -f v4l2 -input_format mjpeg -i /dev/video0 -t 30 output.mp4


But if I specify
-input_format yuyv442
instead, ffmpeg outputs the following and hangs :

ffmpeg version 4.2.4-1ubuntu0.1 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 9 (Ubuntu 9.3.0-10ubuntu2)
 configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
 WARNING: library configuration mismatch
 avcodec configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libaribb24 --enable-liblensfun --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libavresample 4. 0. 0 / 4. 0. 0
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100



If I press Ctl-C, it then prints the following :


Input #0, video4linux2,v4l2, from '/dev/video0':
 Duration: N/A, bitrate: 995328 kb/s
 Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 1920x1080, 995328 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
Stream mapping:
 Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
Press [q] to stop, [?] for help
Finishing stream 0:0 without any data written to it.
[libx264 @ 0x55eda0567640] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0x55eda0567640] profile High 4:2:2, level 4.0, 4:2:2 8-bit
[libx264 @ 0x55eda0567640] 264 - core 155 r2917 0a84d98 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=24 lookahead_threads=4 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'output.mp4':
 Metadata:
 encoder : Lavf58.29.100
 Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv422p, 1920x1080, q=-1--1, 30 fps, 15360 tbn, 30 tbc
 Metadata:
 encoder : Lavc58.54.100 libx264
 Side data:
 cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
frame= 0 fps=0.0 q=0.0 Lsize= 0kB time=00:00:00.00 bitrate=N/A speed= 0x 
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Exiting normally, received signal 2.



Also, if output.mp4 already exists, I get the
Overwrite ? [y/N]
prompt after I Ctl-C.

Does anyone know what is causing this and how I can fix it ?


-
FFMpeg produces low quality target file with just 1 second length on Ubuntu 20.04
16 juillet 2021, par MattI'm using FFMpeg locally on a Mac (actually using PHP-FFMpeg) and it's working perfectly. I'm running the same code on an Ubuntu server and whatever I try the output file is a tiny, low quality video with just 1 second length (the original is about 15 seconds).


I installed it on the server with


sudo apt update
sudo apt install ffmpeg



and then restarted the server. To test now I'm running


ffmpeg -i source.mp4 target.mp4



from the terminal and getting this output


ffmpeg version 4.2.4-1ubuntu0.1 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 9 (Ubuntu 9.3.0-10ubuntu2)
 configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libavresample 4. 0. 0 / 4. 0. 0
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'source.mp4':
 Metadata:
 major_brand : iso5
 minor_version : 1
 compatible_brands: isomiso5hlsf
 creation_time : 2021-07-16T05:37:58.000000Z
 Duration: 00:00:00.66, start: 0.000000, bitrate: 74037 kb/s
 Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 640x480 [SAR 1:1 DAR 4:3], 83522 kb/s, 30.20 fps, 600 tbr, 600 tbn, 1200 tbc (default)
 Metadata:
 creation_time : 2021-07-16T05:37:58.000000Z
 handler_name : Core Media Video
 Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 1774 kb/s (default)
 Metadata:
 creation_time : 2021-07-16T05:37:58.000000Z
 handler_name : Core Media Audio
File 'target.mp4' already exists. Overwrite ? [y/N] y
Stream mapping:
 Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
 Stream #0:1 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 0x55db778748c0] using SAR=1/1
[libx264 @ 0x55db778748c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0x55db778748c0] profile High, level 3.0
[libx264 @ 0x55db778748c0] 264 - core 155 r2917 0a84d98 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
frame= 8 fps=0.0 q=0.0 size= 0kB time=-577014:32:22.77 bitrate= -0.0kbOutput #0, mp4, to 'target.mp4':
 Metadata:
 major_brand : iso5
 minor_version : 1
 compatible_brands: isomiso5hlsf
 encoder : Lavf58.29.100
 Stream #0:0(und): Video: h264 (libx264) (avc1 / 0x31637661), yuv420p(progressive), 640x480 [SAR 1:1 DAR 4:3], q=-1--1, 30.20 fps, 28k tbn, 30.20 tbc (default)
 Metadata:
 creation_time : 2021-07-16T05:37:58.000000Z
 handler_name : Core Media Video
 encoder : Lavc58.54.100 libx264
 Side data:
 cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
 Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 69 kb/s (default)
 Metadata:
 creation_time : 2021-07-16T05:37:58.000000Z
 handler_name : Core Media Audio
 encoder : Lavc58.54.100 aac
frame= 15 fps= 14 q=0.0 size= 0kB time=00:00:00.00 bitrate=N/A dup=3 droframe= 18 fps= 11 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/sframe= 18 fps=7.9 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/sframe= 18 fps=6.4 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/sframe= 19 fps=5.8 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/sframe= 19 fps=5.0 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/sframe= 20 fps=4.6 q=0.0 size= 0kB time=00:00:00.46 bitrate= 0.8kbits/s[aac @ 0x55db778a2f00] Queue input is backward in time
[mp4 @ 0x55db77876100] Non-monotonous DTS in output stream 0:1; previous: 23552, current: 20480; changing to 23553. This may result in incorrect timestamps in the output file.
[mp4 @ 0x55db77876100] Non-monotonous DTS in output stream 0:1; previous: 23553, current: 21504; changing to 23554. This may result in incorrect timestamps in the output file.
[mp4 @ 0x55db77876100] Non-monotonous DTS in output stream 0:1; previous: 23554, current: 22528; changing to 23555. This may result in incorrect timestamps in the output file.
[mp4 @ 0x55db77876100] Non-monotonous DTS in output stream 0:1; previous: 23555, current: 23552; changing to 23556. This may result in incorrect timestamps in the output file.
frame= 20 fps=3.3 q=-1.0 Lsize= 77kB time=00:00:00.56 bitrate=1122.7kbits/s dup=3 drop=3 speed=0.0936x 
video:69kB audio:6kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.688508%
[libx264 @ 0x55db778748c0] frame I:1 Avg QP:22.13 size: 14863
[libx264 @ 0x55db778748c0] frame P:5 Avg QP:25.37 size: 6279
[libx264 @ 0x55db778748c0] frame B:14 Avg QP:26.80 size: 1720
[libx264 @ 0x55db778748c0] consecutive B-frames: 5.0% 0.0% 15.0% 80.0%
[libx264 @ 0x55db778748c0] mb I I16..4: 15.9% 65.9% 18.2%
[libx264 @ 0x55db778748c0] mb P I16..4: 10.6% 11.7% 1.3% P16..4: 52.4% 11.2% 5.5% 0.0% 0.0% skip: 7.4%
[libx264 @ 0x55db778748c0] mb B I16..4: 1.0% 1.3% 0.4% B16..8: 35.8% 3.0% 0.5% direct: 2.4% skip:55.6% L0:41.2% L1:55.5% BI: 3.3%
[libx264 @ 0x55db778748c0] 8x8 transform intra:56.1% inter:82.3%
[libx264 @ 0x55db778748c0] coded y,uvDC,uvAC intra: 54.1% 75.0% 21.1% inter: 14.6% 25.2% 0.1%
[libx264 @ 0x55db778748c0] i16 v,h,dc,p: 9% 19% 3% 70%
[libx264 @ 0x55db778748c0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 18% 24% 5% 6% 9% 6% 6% 6%
[libx264 @ 0x55db778748c0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 30% 20% 16% 6% 7% 7% 6% 5% 3%
[libx264 @ 0x55db778748c0] i8c dc,h,v,p: 48% 25% 22% 5%
[libx264 @ 0x55db778748c0] Weighted P-Frames: Y:40.0% UV:40.0%
[libx264 @ 0x55db778748c0] ref P L0: 62.4% 17.4% 14.3% 5.7% 0.1%
[libx264 @ 0x55db778748c0] ref B L0: 87.6% 10.7% 1.7%
[libx264 @ 0x55db778748c0] ref B L1: 95.0% 5.0%
[libx264 @ 0x55db778748c0] kb/s:849.86
[aac @ 0x55db778a2f00] Qavg: 4594.708



Here's what the files look like




Any ideas what could be wrong ?
Thanks for your help !


-
A pragmatic strategy to merge multiple video files
19 juin 2021, par sauravI currently am working on recording a multiparty video conference which supports up to 6 participants. I am recording the conference using a media server and storing audio/video streams individually for every participant.


Next, I need to merge those individual recordings into a single video file and upload it to a cloud storage like aws s3. For this I am considering 2 options, either Gstreamer or FFMPEG. I am leaning towards FFMPEG as I have used FFMPEG previously. I currently am playing with FFMPEG things like the hstack and vstack filters etc.


Here is the FFMPEG command I recently used to join 2 webm videos of 2 mins 40sec and 1min 40sec to create a mp4 video file for upload. Both the videos are 1280x720 in this case but I have included the scale part because in real life scenario different participants joining with different cameras produces video files of different resolution which is a problem for the hstack/vstack filter. Therefore, to make the video resolutions of all participant consistent, I have included the scale property.


ffmpeg -i 1.webm -i 2.webm -filter_complex "[0:v]scale=1280:720,setsar=1[l];[1:v]scale=1280:720,setsar=1[r];[l][r]hstack;[0][1]amix" output-1280x720.mp4



Currently I am facing 2 issues with this command.


- 

-
The output mp4 file is very big, in this case 140Mb (approx) for a less than 3 minutes video.


-
How do I add delay to any video before starting to merge ?

Currently the videos are going out of sync if all the participants don't join at the same time which is highly unlikely to happen in a real world scenario.







Any pointer in the right direction will be highly appreciated.


Here is a log sample from FFmpeg (or see the full log link) :


ffmpeg version 4.2.4-1ubuntu0.1 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 9 (Ubuntu 9.3.0-10ubuntu2)
 configuration: --prefix=/usr --extra-version=1ubuntu0.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libavresample 4. 0. 0 / 4. 0. 0
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
Input #0, matroska,webm, from '3.webm':
 Metadata:
 title : FFmpeg
 ENCODER : Lavf58.29.100
 Duration: 00:01:39.63, start: 0.000000, bitrate: 707 kb/s
 Stream #0:0: Video: vp8, yuv420p(tv, bt470bg/unknown/unknown, progressive), 1280x720, SAR 1:1 DAR 16:9, 1k tbr, 1k tbn, 1k tbc (default)
 Metadata:
 DURATION : 00:01:39.618000000
 Stream #0:1: Audio: opus, 48000 Hz, stereo, fltp (default)
 Metadata:
 DURATION : 00:01:39.629000000
Input #1, matroska,webm, from '4.webm':
 Metadata:
 title : FFmpeg
 ENCODER : Lavf58.29.100
 Duration: 00:02:39.07, start: 0.000000, bitrate: 708 kb/s
 Stream #1:0: Video: vp8, yuv420p(tv, bt470bg/unknown/unknown, progressive), 1280x720, SAR 1:1 DAR 16:9, 1k tbr, 1k tbn, 1k tbc (default)
 Metadata:
 DURATION : 00:02:39.050000000
 Stream #1:1: Audio: opus, 48000 Hz, stereo, fltp (default)
 Metadata:
 DURATION : 00:02:39.068000000
Stream mapping:
 Stream #0:0 (vp8) -> scale
 Stream #0:1 (opus) -> amix:input0
 Stream #1:0 (vp8) -> scale
 Stream #1:1 (opus) -> amix:input1
 hstack -> Stream #0:0 (libx264)
 amix -> Stream #0:1 (aac)
Press [q] to stop, [?] for help
[libx264 @ 0x562b4842a500] using SAR=1/1
[libx264 @ 0x562b4842a500] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0x562b4842a500] profile High, level 6.1
[libx264 @ 0x562b4842a500] 264 - core 155 r2917 0a84d98 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=18 lookahead_threads=3 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'output-new.mp4':
 Metadata:
 title : FFmpeg
 encoder : Lavf58.29.100
 Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p(progressive), 2560x720 [SAR 1:1 DAR 32:9], q=-1--1, 1k fps, 16k tbn, 1k tbc (default)
 Metadata:
 encoder : Lavc58.54.100 libx264
 Side data:
 cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
 Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
 Metadata:
 encoder : Lavc58.54.100 aac

frame= 129 fps=0.0 q=33.0 size= 0kB time=00:00:00.23 bitrate= 1.6kbits/s dup=123 drop=0 speed=0.44x 
frame= 257 fps=228 q=33.0 size= 0kB time=00:00:00.51 bitrate= 0.8kbits/s dup=243 drop=0 speed=0.455x 
frame= 379 fps=224 q=33.0 size= 256kB time=00:00:00.73 bitrate=2855.1kbits/s dup=358 drop=0 speed=0.434x 
frame= 497 fps=222 q=33.0 size= 256kB time=00:00:00.86 bitrate=2431.5kbits/s dup=469 drop=0 speed=0.386x 
 
...
More than 1000 frames duplicated
...
 
frame=158751 fps=196 q=33.0 size= 134656kB time=00:02:39.00 bitrate=6937.4kbits/s dup=151385 drop=0 speed=0.196x 
frame=158851 fps=196 q=33.0 size= 134912kB time=00:02:39.00 bitrate=6950.6kbits/s dup=151482 drop=0 speed=0.196x 
frame=158983 fps=196 q=33.0 size= 134912kB time=00:02:39.00 bitrate=6950.6kbits/s dup=151610 drop=0 speed=0.196x 
frame=159081 fps=196 q=-1.0 Lsize= 137197kB time=00:02:39.07 bitrate=7065.2kbits/s dup=151706 drop=0 speed=0.196x 

video:132693kB audio:2494kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.486001%

[libx264 @ 0x562b4842a500] frame I:637 Avg QP:17.73 size:123895
[libx264 @ 0x562b4842a500] frame P:40088 Avg QP:19.73 size: 1134
[libx264 @ 0x562b4842a500] frame B:118356 Avg QP:27.54 size: 97
[libx264 @ 0x562b4842a500] consecutive B-frames: 0.8% 0.0% 0.0% 99.2%
[libx264 @ 0x562b4842a500] mb I I16..4: 11.1% 67.3% 21.6%
[libx264 @ 0x562b4842a500] mb P I16..4: 0.1% 0.1% 0.0% P16..4: 2.6% 0.4% 0.3% 0.0% 0.0% skip:96.5%
[libx264 @ 0x562b4842a500] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 0.7% 0.0% 0.0% direct: 0.0% skip:99.3% L0:38.7% L1:61.3% BI: 0.0%
[libx264 @ 0x562b4842a500] 8x8 transform intra:66.8% inter:71.4%
[libx264 @ 0x562b4842a500] coded y,uvDC,uvAC intra: 81.8% 89.5% 72.3% inter: 0.2% 0.4% 0.0%
[libx264 @ 0x562b4842a500] i16 v,h,dc,p: 25% 21% 17% 37%
[libx264 @ 0x562b4842a500] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33% 22% 12% 4% 5% 6% 6% 6% 6%
[libx264 @ 0x562b4842a500] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 42% 24% 6% 4% 5% 5% 6% 4% 4%
[libx264 @ 0x562b4842a500] i8c dc,h,v,p: 42% 24% 26% 9%
[libx264 @ 0x562b4842a500] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x562b4842a500] ref P L0: 82.4% 11.5% 5.3% 0.8%
[libx264 @ 0x562b4842a500] ref B L0: 83.0% 16.9% 0.1%
[libx264 @ 0x562b4842a500] ref B L1: 94.9% 5.1%
[libx264 @ 0x562b4842a500] kb/s:6833.11
[aac @ 0x562b4842b540] Qavg: 239.393



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