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Géodiversité
9 septembre 2011, par ,
Mis à jour : Août 2018
Langue : français
Type : Texte
Autres articles (17)
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Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
Les formats acceptés
28 janvier 2010, parLes commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
ffmpeg -codecs ffmpeg -formats
Les format videos acceptés en entrée
Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
Les formats vidéos de sortie possibles
Dans un premier temps on (...) -
MediaSPIP Init et Diogène : types de publications de MediaSPIP
11 novembre 2010, parÀ l’installation d’un site MediaSPIP, le plugin MediaSPIP Init réalise certaines opérations dont la principale consiste à créer quatre rubriques principales dans le site et de créer cinq templates de formulaire pour Diogène.
Ces quatre rubriques principales (aussi appelées secteurs) sont : Medias ; Sites ; Editos ; Actualités ;
Pour chacune de ces rubriques est créé un template de formulaire spécifique éponyme. Pour la rubrique "Medias" un second template "catégorie" est créé permettant d’ajouter (...)
Sur d’autres sites (6693)
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capture my webcam and encode to mp4 with ffmpeg, but the x264 works bad
17 septembre 2015, par zhangxm1991here is my version :
ffmpeg version : 2.3.3
libx264 version:142.xI wat to capture my video and use ffmpeg and x264 to a mp4 file. the solution is 320x240.
But i found that the video file is so big. Then i found that the P frame and B frame is very big, even nearly equal to the I frame.I do not know why.here is my code :
c->codec_id = codec_id;
c->bit_rate = 400000;
c->width = 320;
c->height = 240;
c->time_base.den = 10;
c->time_base.num = 1;
c->pix_fmt = AV_PIX_FMT_YUV420P;Here is my program output :
[libx264 @ 0xb6200fc0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0xb6200fc0] profile High, level 1.3
[libx264 @ 0xb6200fc0] 264 - core 142 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - 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=6 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=10 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=400 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to '/home/2014_09_12/0002b6429579/5/2014_09_12_18_39_12_600.mp4':
Stream #0:0: Video: h264 (libx264), yuv420p, 320x240, q=-1--1, 400 kb/s, 10 tbc
Stream #0:1: Audio: aac, 8000 Hz, mono, fltp, 32 kb/s
[mp4 @ 0xb62005e0] Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
[mp4 @ 0xb62005e0] Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
[mp4 @ 0xb62005e0] Encoder did not produce proper pts, making some up.
[libx264 @ 0xb6200fc0] frame I:3 Avg QP: 2.79 size: 72996
[libx264 @ 0xb6200fc0] frame P:383 Avg QP: 0.14 size: 54075
[libx264 @ 0xb6200fc0] frame B:216 Avg QP: 1.95 size: 64784
[libx264 @ 0xb6200fc0] consecutive B-frames: 30.1% 63.2% 6.0% 0.7%
[libx264 @ 0xb6200fc0] mb I I16..4: 16.1% 12.7% 71.2%
[libx264 @ 0xb6200fc0] mb P I16..4: 3.5% 5.1% 15.9% P16..4: 20.3% 22.8% 14.0% 0.0% 0.0% skip:18.3%
[libx264 @ 0xb6200fc0] mb B I16..4: 0.4% 2.5% 8.2% B16..8: 32.6% 19.8% 13.5%
direct:22.2% skip: 0.8% L0:25.5% L1:12.8% BI:61.6%
[libx264 @ 0xb6200fc0] final ratefactor: -32.89
[libx264 @ 0xb6200fc0] 8x8 transform intra:21.0% inter:29.6%
[libx264 @ 0xb6200fc0] coded y,uvDC,uvAC intra: 100.0% 100.0% 100.0% inter: 83.3% 80.9% 80.9%
[libx264 @ 0xb6200fc0] i16 v,h,dc,p: 5% 7% 42% 46%
[libx264 @ 0xb6200fc0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 14% 12% 23% 8% 6% 6% 8% 9% 14%
[libx264 @ 0xb6200fc0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 11% 19% 10% 8% 8% 10% 10% 12%
[libx264 @ 0xb6200fc0] i8c dc,h,v,p: 78% 3% 4% 15%
[libx264 @ 0xb6200fc0] Weighted P-Frames: Y:0.5% UV:0.3%
[libx264 @ 0xb6200fc0] ref P L0: 43.4% 14.6% 19.0% 22.9% 0.1%
[libx264 @ 0xb6200fc0] ref B L0: 63.3% 35.7% 1.1%
[libx264 @ 0xb6200fc0] ref B L1: 97.0% 3.0%
[libx264 @ 0xb6200fc0] kb/s:4.53
[aac @ 0xb6201ba0] 2 frames left in the queue on closing -
capture my webcam and encode to mp4 with ffmpeg, but the x264 works bad
17 septembre 2015, par zhangxm1991here is my version :
ffmpeg version : 2.3.3
libx264 version:142.xI wat to capture my video and use ffmpeg and x264 to a mp4 file. the solution is 320x240.
But i found that the video file is so big. Then i found that the P frame and B frame is very big, even nearly equal to the I frame.I do not know why.here is my code :
c->codec_id = codec_id;
c->bit_rate = 400000;
c->width = 320;
c->height = 240;
c->time_base.den = 10;
c->time_base.num = 1;
c->pix_fmt = AV_PIX_FMT_YUV420P;Here is my program output :
[libx264 @ 0xb6200fc0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0xb6200fc0] profile High, level 1.3
[libx264 @ 0xb6200fc0] 264 - core 142 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - 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=6 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=10 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=400 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to '/home/2014_09_12/0002b6429579/5/2014_09_12_18_39_12_600.mp4':
Stream #0:0: Video: h264 (libx264), yuv420p, 320x240, q=-1--1, 400 kb/s, 10 tbc
Stream #0:1: Audio: aac, 8000 Hz, mono, fltp, 32 kb/s
[mp4 @ 0xb62005e0] Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
[mp4 @ 0xb62005e0] Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
[mp4 @ 0xb62005e0] Encoder did not produce proper pts, making some up.
[libx264 @ 0xb6200fc0] frame I:3 Avg QP: 2.79 size: 72996
[libx264 @ 0xb6200fc0] frame P:383 Avg QP: 0.14 size: 54075
[libx264 @ 0xb6200fc0] frame B:216 Avg QP: 1.95 size: 64784
[libx264 @ 0xb6200fc0] consecutive B-frames: 30.1% 63.2% 6.0% 0.7%
[libx264 @ 0xb6200fc0] mb I I16..4: 16.1% 12.7% 71.2%
[libx264 @ 0xb6200fc0] mb P I16..4: 3.5% 5.1% 15.9% P16..4: 20.3% 22.8% 14.0% 0.0% 0.0% skip:18.3%
[libx264 @ 0xb6200fc0] mb B I16..4: 0.4% 2.5% 8.2% B16..8: 32.6% 19.8% 13.5%
direct:22.2% skip: 0.8% L0:25.5% L1:12.8% BI:61.6%
[libx264 @ 0xb6200fc0] final ratefactor: -32.89
[libx264 @ 0xb6200fc0] 8x8 transform intra:21.0% inter:29.6%
[libx264 @ 0xb6200fc0] coded y,uvDC,uvAC intra: 100.0% 100.0% 100.0% inter: 83.3% 80.9% 80.9%
[libx264 @ 0xb6200fc0] i16 v,h,dc,p: 5% 7% 42% 46%
[libx264 @ 0xb6200fc0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 14% 12% 23% 8% 6% 6% 8% 9% 14%
[libx264 @ 0xb6200fc0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 11% 19% 10% 8% 8% 10% 10% 12%
[libx264 @ 0xb6200fc0] i8c dc,h,v,p: 78% 3% 4% 15%
[libx264 @ 0xb6200fc0] Weighted P-Frames: Y:0.5% UV:0.3%
[libx264 @ 0xb6200fc0] ref P L0: 43.4% 14.6% 19.0% 22.9% 0.1%
[libx264 @ 0xb6200fc0] ref B L0: 63.3% 35.7% 1.1%
[libx264 @ 0xb6200fc0] ref B L1: 97.0% 3.0%
[libx264 @ 0xb6200fc0] kb/s:4.53
[aac @ 0xb6201ba0] 2 frames left in the queue on closing -
Problem with ffplay from webcam stream using complex filters
29 mai 2022, par efelbarI'm trying to stream video from a webcam (at
/dev/video2
) through ffplay to scale and recolor it, add some text, and then reduce the number of colors with palettes. I don't get any errors, but running the ffplay command :

ffplay -i /dev/video2 -vf "hflip,\
 colorbalance=\
 rs=0.4:\
 bs=-0.4\
 ,\
 scale=\
 trunc(iw/8):\
 trunc(ih/8)\
 ,\
 drawtext=\
 text=\
 'efelbar':\
 fontcolor=white:\
 fontsize=10:\
 box=1:\
 boxcolor=black:\
 boxborderw=5:\
 x=(w-text_w)/2:\
 y=(h-text_h)/2\
 ,\
 split[s0][s1];\
 [s0]palettegen=\
 max_colors=16\
 [p];\
 [s1][p]paletteuse"



seems to stall, and fails to produce video output.


Running the simpler command
ffplay -i /dev/video2 -vf "split[s0][s1];[s0]palettegen=max_colors=16[p];[s1][p]paletteuse"
, which takes a stream from a webcam and (should) reduce the number of colors, results in it just sitting there without showing the actual output stream. This might just be a performance issue because I'm on older hardware, but it doesn't give output relfective of that.

The output of that command is as follows :


ffplay version n5.0 Copyright (c) 2003-2022 the FFmpeg developers
 built with gcc 11.2.0 (GCC)
 configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-amf --enable-avisynth --enable-cuda-llvm --enable-lto --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmfx --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librav1e --enable-librsvg --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-libzimg --enable-nvdec --enable-nvenc --enable-shared --enable-version3
 libavutil 57. 17.100 / 57. 17.100
 libavcodec 59. 18.100 / 59. 18.100
 libavformat 59. 16.100 / 59. 16.100
 libavdevice 59. 4.100 / 59. 4.100
 libavfilter 8. 24.100 / 8. 24.100
 libswscale 6. 4.100 / 6. 4.100
 libswresample 4. 3.100 / 4. 3.100
 libpostproc 56. 3.100 / 56. 3.100
Input #0, video4linux2,v4l2, from '/dev/video2':B sq= 0B f=0/0 
 Duration: N/A, start: 254970.739108, bitrate: 147456 kb/s
 Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 640x480, 147456 kb/s, 30 fps, 30 tbr, 1000k tbn



I'm running this on a thinkpad t420s, so I definitely wouldn't be surprised if my laptop just can't process video that quickly. If that is the case, suggestions for optimizations would be great !