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Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page. -
La sauvegarde automatique de canaux SPIP
1er avril 2010, parDans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...) -
Script d’installation automatique de MediaSPIP
25 avril 2011, parAfin de palier aux difficultés d’installation dues principalement aux dépendances logicielles coté serveur, un script d’installation "tout en un" en bash a été créé afin de faciliter cette étape sur un serveur doté d’une distribution Linux compatible.
Vous devez bénéficier d’un accès SSH à votre serveur et d’un compte "root" afin de l’utiliser, ce qui permettra d’installer les dépendances. Contactez votre hébergeur si vous ne disposez pas de cela.
La documentation de l’utilisation du script d’installation (...)
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Anomalie #2555 : Défaut graphique du survol sur barre typo
5 mars 2012, par cedric -Je n’ai aucun avis sur la question, je note juste que ce qu’on qualifie ici de défaut est juste le résultat de deux avis et commit contraires. C’est donc un défaut pour l’un, un avantage pour l’autre. Je pense qu’il faut surtout que vous vous mettiez d’accord. La correction est ensuite (...)
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Encode x264 video with ffmpeg for Android with starting offset
4 août 2013, par scubedI'm trying to convert a video to play on an Android device.
The video is from a big movie. I am chopping it back into pieces
to correspond with the actual segments of the movie using -ss and -t.The input is mp4 with H.264 and AAC.
The output is mkv using H.264 and Vorbis.Specifically, the input is :
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 320x240, 2240 kb/s, 29.97 fps, 60 tbr, 90k tbn, 180k tbc
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 162 kb/sI'm using : ffmpeg version 1.0.7
The command I'm trying is something like :
ffmpeg -ss 00:03:52.000 -i in.mp4 -t 00:01:00.000 -c:v libx264 -preset medium -crf 20 -maxrate 400k -bufsize 1835k -c:a libvorbis -sn out.mkv
However, while the resulting video works fine on my computer, when I click on
my phone, it says : Can't play video
and checking the Android log, it has :E/SoftAVC (24319): Decoder failed: -2
E/OMXCodec(24319): [OMX.google.h264.decoder] ERROR(0x80001001, -1007)It is still able to make a thumbnail for the movie, but not play it.
Interestingly, some simple variations of that command do work :
Remove -ss to start at the beginning of the video
Use -an to disable audioThese variations still failed :
Copying the original audio with -c:a copy, or other audio codecs like vorbis, mp3
Using mp4 instead of mkv
Using baseline H.264 profile, including restricting level to 1.2.Running through mkvmerge first not only fails, but makes Android not able to even make a thumbnail.
I don't know if it is related, but another small thing I noticed is that for
starting transcoding later in the movie, the audio starts out slightly out-of-sync.
After several seconds, it gets back in sync. The audio is in sync in the original.Robert Rowntree :
-vcodec libx264 -b:v 200k -bt 50k -threads 0 -b_strategy 1 -acodec copy -f mp4 -strict -2
Interesting. Your command almost works. The video actually plays on Android. The one problem is that the audio is out-of-sync and stays out-of-sync throughout the whole clip. But, that's much closer than I've been. I'll search around there and see if I can find the right combination.
I tried combinations of it. It appears that using both mp4 and copying the audio is what allows it to work. Using libvorbis or going to mkv breaks it again. But, I would like to transcode the audio, and I suspect to keep it in sync, I might have to transcode it anyways. Note that even with transcoding, when I play it back on the computer, I still don't have sync between audio and video.
LordNeckbeard :
Here is the complete log.ffmpeg version 1.0.7 Copyright (c) 2000-2013 the FFmpeg developers
built on Jul 27 2013 13:01:19 with gcc 4.4.5 (Gentoo 4.4.5 p1.2, pie-0.4.5)
configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --enable-shared --cc=x86_64-pc-linux-gnu-gcc --cxx=x86_64-pc-linux-gnu-g++ --ar=x86_64-pc-linux-gnu-ar --optflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --extra-cflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --extra-cxxflags='-mtune=athlon64 -O2 -pipe -fomit-frame-pointer -fstack-protector' --disable-static --enable-gpl --enable-version3 --enable-postproc --enable-avfilter --enable-avresample --disable-stripping --disable-debug --disable-doc --disable-vaapi --disable-runtime-cpudetect --enable-libmp3lame --enable-libvo-aacenc --enable-libtheora --enable-libx264 --enable-libxvid --enable-libcaca --enable-openal --disable-indev=v4l2 --disable-indev=oss --disable-indev=jack --enable-x11grab --disable-outdev=oss --enable-libfreetype --enable-pthreads --enable-libspeex --enable-libvorbis --disable-altivec --disable-avx --disable-vis --disable-neon --cpu=athlon64 - libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 59.100 / 54. 59.100
libavformat 54. 29.104 / 54. 29.104
libavdevice 54. 2.101 / 54. 2.101
libavfilter 3. 17.100 / 3. 17.100
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
libpostproc 52. 0.100 / 52. 0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'in.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: mp42isomavc1
creation_time : 2013-07-13 02:23:51
encoder : HandBrake 0.9.6 2012022800
Duration: 03:14:01.41, start: 0.000000, bitrate: 2408 kb/s
Chapter #0.0: start -0.133467, end 648.697411
Metadata:
title : Chapter 1
Chapter #0.1: start 648.697411, end 1297.345411
Metadata:
title : Chapter 2
Chapter #0.2: start 1297.345411, end 1729.777411
Metadata:
title : Chapter 3
Chapter #0.3: start 1729.777411, end 2378.425411
Metadata:
title : Chapter 4
Chapter #0.4: start 2378.425411, end 3027.073411
Metadata:
title : Chapter 5
Chapter #0.5: start 3027.073411, end 3675.721411
Metadata:
title : Chapter 6
Chapter #0.6: start 3675.721411, end 4108.153411
Metadata:
title : Chapter 7
Chapter #0.7: start 4108.153411, end 4756.801411
Metadata:
title : Chapter 8
Chapter #0.8: start 4756.801411, end 5405.449411
Metadata:
title : Chapter 9
Chapter #0.9: start 5405.449411, end 6054.097411
Metadata:
title : Chapter 10
Chapter #0.10: start 6054.097411, end 6702.745411
Metadata:
title : Chapter 11
Chapter #0.11: start 6702.745411, end 7135.177411
Metadata:
title : Chapter 12
Chapter #0.12: start 7135.177411, end 7783.825411
Metadata:
title : Chapter 13
Chapter #0.13: start 7783.825411, end 8432.473411
Metadata:
title : Chapter 14
Chapter #0.14: start 8432.473411, end 9081.121411
Metadata:
title : Chapter 15
Chapter #0.15: start 9081.121411, end 9513.553411
Metadata:
title : Chapter 16
Chapter #0.16: start 9513.553411, end 10162.201411
Metadata:
title : Chapter 17
Chapter #0.17: start 10162.201411, end 10810.849411
Metadata:
title : Chapter 18
Chapter #0.18: start 10810.849411, end 11459.497411
Metadata:
title : Chapter 19
Chapter #0.19: start 11459.497411, end 11641.412478
Metadata:
title : Chapter 20
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 320x240, 2240 kb/s, 29.97 fps, 60 tbr, 90k tbn, 180k tbc
Metadata:
creation_time : 2013-07-13 02:23:51
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 162 kb/s
Metadata:
creation_time : 2013-07-13 02:23:51
Stream #0:2(und): Subtitle: mov_text (text / 0x74786574)
Metadata:
creation_time : 2013-07-13 02:23:51
[libx264 @ 0x14ea220] using cpu capabilities: MMX2 SSE2Slow SlowCTZ
[libx264 @ 0x14ea220] profile High, level 2.1
[libx264 @ 0x14ea220] 264 - core 120 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - 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 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=60 keyint_min=6 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=20.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=400 vbv_bufsize=1835 crf_max=0.0 nal_hrd=none ip_ratio=1.40 aq=1:1.00
Output #0, matroska, to 'out.mkv':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: mp42isomavc1
encoder : Lavf54.29.104
Chapter #0.0: start 0.000000, end 60.000000
Metadata:
title : Chapter 1
Stream #0:0(und): Video: h264 (H264 / 0x34363248), yuv420p, 320x240, q=-1--1, 1k tbn, 60 tbc
Metadata:
creation_time : 2013-07-13 02:23:51
Stream #0:1(und): Audio: vorbis (oV[0][0] / 0x566F), 48000 Hz, stereo, flt
Metadata:
creation_time : 2013-07-13 02:23:51
Stream mapping:
Stream #0:0 -> #0:0 (h264 -> libx264)
Stream #0:1 -> #0:1 (aac -> libvorbis)
Press [q] to stop, [?] for help
frame= 1799 fps= 92 q=-1.0 Lsize= 3738kB time=00:00:59.98 bitrate= 510.5kbits/s dup=0 drop=51 =51
video:3016kB audio:683kB subtitle:0 global headers:4kB muxing overhead 0.939943%
[libx264 @ 0x14ea220] frame I:31 Avg QP:20.23 size: 14126
[libx264 @ 0x14ea220] frame P:634 Avg QP:23.03 size: 3317
[libx264 @ 0x14ea220] frame B:1134 Avg QP:27.71 size: 482
[libx264 @ 0x14ea220] consecutive B-frames: 2.3% 12.8% 84.7% 0.2%
[libx264 @ 0x14ea220] mb I I16..4: 3.8% 63.8% 32.4%
[libx264 @ 0x14ea220] mb P I16..4: 0.1% 0.3% 0.1% P16..4: 47.4% 30.2% 19.5% 0.0% 0.0% skip: 2.4%
[libx264 @ 0x14ea220] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 35.2% 3.0% 0.6% direct: 8.8% skip:52.3% L0:28.7% L1:63.9% BI: 7.4%
[libx264 @ 0x14ea220] 8x8 transform intra:64.0% inter:59.5%
[libx264 @ 0x14ea220] coded y,uvDC,uvAC intra: 94.2% 99.5% 95.5% inter: 23.3% 55.5% 14.0%
[libx264 @ 0x14ea220] i16 v,h,dc,p: 75% 10% 5% 10%
[libx264 @ 0x14ea220] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 16% 12% 8% 7% 8% 8% 11% 11%
[libx264 @ 0x14ea220] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 17% 20% 7% 8% 9% 9% 10% 10% 11%
[libx264 @ 0x14ea220] i8c dc,h,v,p: 38% 31% 14% 17%
[libx264 @ 0x14ea220] Weighted P-Frames: Y:7.3% UV:4.4%
[libx264 @ 0x14ea220] ref P L0: 48.8% 14.2% 29.1% 7.5% 0.4%
[libx264 @ 0x14ea220] ref B L0: 65.4% 30.8% 3.7%
[libx264 @ 0x14ea220] ref B L1: 89.0% 11.0%
[libx264 @ 0x14ea220] kb/s:411.70 -
Availability of WebM (VP8) Video Hardware IP Designs
10 janvier 2011, par noreply@blogger.com (John Luther)Hello from the frigid city of Oulu, in the far north of Finland. Our WebM hardware development team, formerly part of On2 Technologies, is now up-to-speed and working hard on a number of video efforts for WebM.
- VP8 (the video codec used in WebM) hardware decoder IP is available from Google for semiconductor companies who want to support high-quality WebM playback in their chipsets.
- The Oulu team will release the first VP8 video hardware encoder IP in the first quarter of 2011. We have the IP running in an FPGA environment, and rigorous testing is underway. Once all features have been tested and implemented, the encoder will be launched as well.
WebM video hardware IPs are implemented and delivered as RTL (VHDL/Verilog) source code, which is a register-level hardware description language for creating digital circuit designs. The code is based on the Hantro brand video IP from On2, which has been successfully deployed by numerous chipset companies around the world. Our designs support VP8 up to 1080p resolution and can run 30 or 60fps, depending on the foundry process and hardware clock frequency.
The WebM/VP8 hardware decoder implementation has already been licensed to over twenty partners and is proven in silicon. We expect the first commercial chips to integrate our VP8 decoder IP to be available in the first quarter of 2011. For example, Chinese semiconductor maker Rockchip last week demonstrated full WebM hardware playback on their new RK29xx series processor at CES in Las Vegas (video below).
Note : To view the video in WebM format, ensure that you’ve enrolled in the YouTube HTML5 trial and are using a WebM-compatible browser. You can also view the video on YouTube.Hardware implementations of the VP8 encoder also bring exciting possibilities for WebM in portable devices. Not only can hardware-accelerated devices play high-quality WebM content, but hardware encoding also enables high-resolution, real-time video communications apps on the same devices. For example, when VP8 video encoding is fully off-loaded to a hardware accelerator, you can run 720p or even 1080p video conferencing at full framerate on a portable device with minimal battery use.
The WebM hardware video IP team will be focusing on further developing the VP8 hardware designs while also helping our semiconductor partners to implement WebM video compression in their chipsets. If you have any questions, please visit our Hardware page.
Happy New Year to the WebM community !
Jani Huoponen, Product Manager
Aki Kuusela, Engineering Manager