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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (46)
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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 (...) -
Ajouter notes et légendes aux images
7 février 2011, parPour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
Modification lors de l’ajout d’un média
Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...) -
Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
Sur d’autres sites (9235)
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How to solve libx264 not found when building ffmpeg-with-libx264-enabled for android ?
6 mars 2012, par newentryi am trying build android-ffmpeg-x264 downloaded from git. Link https://github.com/halfninja/android-ffmpeg-x264
After running ./config_make_everything.sh i am getting following error
ERROR : libx264 not found
If you think configure made a mistake, make sure you are using the latest
version from Git. If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "config.log" produced by configure as this will help
solving the problem.<pre>
Makefile:1: config.mak: No such file or directory
libavutil/Makefile:1: libavutil/../config.mak: No such file or directory
libavutil/../subdir.mak:96: warning: overriding commands for target `libavutil/'
libavutil/../subdir.mak:26: warning: ignoring old commands for target `libavutil/'
libavutil/../subdir.mak:96: warning: overriding commands for target `libavutil/'
libavutil/../subdir.mak:96: warning: ignoring old commands for target `libavutil/'
tests/Makefile:44: /tests/fate.mak: No such file or directory
tests/Makefile:45: /tests/fate2.mak: No such file or directory
tests/Makefile:47: /tests/fate/aac.mak: No such file or directory
tests/Makefile:48: /tests/fate/als.mak: No such file or directory
tests/Makefile:49: /tests/fate/fft.mak: No such file or directory
tests/Makefile:50: /tests/fate/h264.mak: No such file or directory
tests/Makefile:51: /tests/fate/mp3.mak: No such file or directory
tests/Makefile:52: /tests/fate/vorbis.mak: No such file or directory
tests/Makefile:53: /tests/fate/vp8.mak: No such file or directory
make: *** No rule to make target `/tests/fate/vp8.mak'. Stop.
</pre>config.log contains
<pre>
ratecontrol.c:(.text+0xa400): undefined reference to `memset'
ratecontrol.c:(.text+0xa41c): undefined reference to `memset'
ratecontrol.c:(.text+0xa448): undefined reference to `__aeabi_l2d'
ratecontrol.c:(.text+0xa49c): undefined reference to `__aeabi_ldivmod'
ratecontrol.c:(.text+0xa4a0): undefined reference to `__aeabi_l2d'
ratecontrol.c:(.text+0xa4f8): undefined reference to `__aeabi_idivmod'
ratecontrol.c:(.text+0xa794): undefined reference to `__aeabi_l2d'
../x264/libx264.a(set.o): In function `x264_validate_levels':
set.c:(.text+0x200): undefined reference to `__aeabi_ldivmod'
set.c:(.text+0x334): undefined reference to `__aeabi_idiv'
../x264/libx264.a(set.o): In function `x264_sei_version_write':
set.c:(.text+0xeec): undefined reference to `strlen'
set.c:(.text+0xf10): undefined reference to `memcpy'
set.c:(.text+0xf3c): undefined reference to `sprintf'
set.c:(.text+0xf44): undefined reference to `strlen'
../x264/libx264.a(set.o): In function `scaling_list_write':
set.c:(.text+0x20b0): undefined reference to `memcmp'
set.c:(.text+0x2138): undefined reference to `memcmp'
set.c:(.text+0x2158): undefined reference to `memcmp'
../x264/libx264.a(set.o): In function `x264_pps_write':
set.c:(.text+0x5870): undefined reference to `memcmp'
set.c:(.text+0x5a7c): undefined reference to `memcmp'
../x264/libx264.a(set.o):set.c:(.text+0x5a9c): more undefined references to `memcmp' follow
../x264/libx264.a(macroblock.o): In function `x264_noise_reduction_update':
macroblock.c:(.text+0xe10): undefined reference to `__aeabi_uldivmod'
../x264/libx264.a(macroblock.o): In function `x264_predict_lossless_8x8_chroma':
macroblock.c:(.text+0x3224): undefined reference to `memcpy'
macroblock.c:(.text+0x323c): undefined reference to `memcpy'
../x264/libx264.a(cabac.o): In function `x264_macroblock_write_cabac':
cabac.c:(.text+0x2c58): undefined reference to `__assert2'
cabac.c:(.text+0x2dd8): undefined reference to `__assert2'
cabac.c:(.text+0x2f80): undefined reference to `__assert2'
cabac.c:(.text+0x3020): undefined reference to `__assert2'
../x264/libx264.a(rectangle.o): In function `x264_macroblock_cache_ref_1_1':
rectangle.c:(.text+0x1e4): undefined reference to `__assert2'
../x264/libx264.a(rectangle.o):rectangle.c:(.text+0x210): more undefined references to `__assert2' follow
ERROR: libx264 not found
</pre>1.I am using fedora to build both ffmpeg and x264
2.NDK r7Any solution to successfully build the code ?
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YouTube's HD Video Streaming Server Technology ?
30 septembre 2013, par bgentryLately I've been researching different methods for streaming MP4s to the browser. Flash Media Server is an obvious choice here (using Cloudfront), and most solutions I've seen use the RTMP protocol.
However, I spent some time on YouTube with Firebug and Chrome debugger figuring out how their streaming worked and I discovered some interesting differences between some of their videos and quality rates.
My two sample videos are A and B. A is available up to 480p and B is available up to 1080p. For both videos, all rates up to 480p are served in an FLV container with H.264 video and AAC audio, over HTTP. What's interesting here is that if you have not yet downloaded (cached) the entire video, and you try to skip forward to an uncached part of the video, a new request will be made with a 'begin' parameter equal to the target offset in milliseconds. Example from Video A at 480p :
http://v11.lscache8.c.youtube.com/videoplayback?ip=0.0.0.0&sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Calgorithm%2Cburst%2Cfactor%2Coc%3AU0dWTldQVF9FSkNNNl9PSlhJ&fexp=904806%2C902906%2C903711&algorithm=throttle-factor&itag=35&ipbits=0&burst=40&sver=3&expire=1279756800&key=yt1&signature=D2D704D63C242CF187CAA5B5D5BAFB8DFACAC5FF.39180C01559C976717B651A7EB1D0C6249231EB7&factor=1.25&id=8568eb3135971f6f&begin=111863
Response Headers:
Cache-Control:public,max-age=23472
Connection:close
Content-Length:14320637
Content-Type:video/x-flv
Date:Wed, 21 Jul 2010 17:23:48 GMT
Expires:Wed, 21 Jul 2010 23:55:00 GMT
Last-Modified:Wed, 19 May 2010 12:31:41 GMT
Server:gvs 1.0
X-Content-Type-Options:nosniffThe file returned by this URL is a fully valid FLV containing only the portion of the video after the requested offset.
I did the same kind of test on the higher resolution versions of Video B. At 720p and 1080p, YouTube will return a video in an MP4 container, also with H.264 video and AAC audio. What's impressive to me is that their server takes the same type of offset for an MP4 video (via the 'begin' parameter) and returns a valid, streamable MP4 (moov atom at the front of the file with correct offsets) that also only includes the requested portion of the video.
So, how does YouTube do this ? How do they generate the FLV or MP4 container on the fly with the correct headers and only the desired segment of the requested video ? I know this can be accomplished using FFMPEG to seek to the desired start point and the qt-faststart script to reposition the moov atom to the front of the stream, but it seems like this would be too slow to handle on-demand for millions of YouTube viewers.
Ideas ?
Thanks in advance !
Footnote : I am not allowed to include more than 1 link at this point, so here is Video A's URL : http:// www.youtube .com/watch ?v=hWjrMTWXH28 "Video available up to 480p"
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How to solve libx264 not found when building ffmpeg-with-libx264-enabled for android ?
6 mars 2012, par newentryi am trying build android-ffmpeg-x264 downloaded from git. Link https://github.com/halfninja/android-ffmpeg-x264
After running ./config_make_everything.sh i am getting following error
ERROR : libx264 not found
If you think configure made a mistake, make sure you are using the latest
version from Git. If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "config.log" produced by configure as this will help
solving the problem.<pre>
Makefile:1: config.mak: No such file or directory
libavutil/Makefile:1: libavutil/../config.mak: No such file or directory
libavutil/../subdir.mak:96: warning: overriding commands for target `libavutil/'
libavutil/../subdir.mak:26: warning: ignoring old commands for target `libavutil/'
libavutil/../subdir.mak:96: warning: overriding commands for target `libavutil/'
libavutil/../subdir.mak:96: warning: ignoring old commands for target `libavutil/'
tests/Makefile:44: /tests/fate.mak: No such file or directory
tests/Makefile:45: /tests/fate2.mak: No such file or directory
tests/Makefile:47: /tests/fate/aac.mak: No such file or directory
tests/Makefile:48: /tests/fate/als.mak: No such file or directory
tests/Makefile:49: /tests/fate/fft.mak: No such file or directory
tests/Makefile:50: /tests/fate/h264.mak: No such file or directory
tests/Makefile:51: /tests/fate/mp3.mak: No such file or directory
tests/Makefile:52: /tests/fate/vorbis.mak: No such file or directory
tests/Makefile:53: /tests/fate/vp8.mak: No such file or directory
make: *** No rule to make target `/tests/fate/vp8.mak'. Stop.
</pre>config.log contains
<pre>
ratecontrol.c:(.text+0xa400): undefined reference to `memset'
ratecontrol.c:(.text+0xa41c): undefined reference to `memset'
ratecontrol.c:(.text+0xa448): undefined reference to `__aeabi_l2d'
ratecontrol.c:(.text+0xa49c): undefined reference to `__aeabi_ldivmod'
ratecontrol.c:(.text+0xa4a0): undefined reference to `__aeabi_l2d'
ratecontrol.c:(.text+0xa4f8): undefined reference to `__aeabi_idivmod'
ratecontrol.c:(.text+0xa794): undefined reference to `__aeabi_l2d'
../x264/libx264.a(set.o): In function `x264_validate_levels':
set.c:(.text+0x200): undefined reference to `__aeabi_ldivmod'
set.c:(.text+0x334): undefined reference to `__aeabi_idiv'
../x264/libx264.a(set.o): In function `x264_sei_version_write':
set.c:(.text+0xeec): undefined reference to `strlen'
set.c:(.text+0xf10): undefined reference to `memcpy'
set.c:(.text+0xf3c): undefined reference to `sprintf'
set.c:(.text+0xf44): undefined reference to `strlen'
../x264/libx264.a(set.o): In function `scaling_list_write':
set.c:(.text+0x20b0): undefined reference to `memcmp'
set.c:(.text+0x2138): undefined reference to `memcmp'
set.c:(.text+0x2158): undefined reference to `memcmp'
../x264/libx264.a(set.o): In function `x264_pps_write':
set.c:(.text+0x5870): undefined reference to `memcmp'
set.c:(.text+0x5a7c): undefined reference to `memcmp'
../x264/libx264.a(set.o):set.c:(.text+0x5a9c): more undefined references to `memcmp' follow
../x264/libx264.a(macroblock.o): In function `x264_noise_reduction_update':
macroblock.c:(.text+0xe10): undefined reference to `__aeabi_uldivmod'
../x264/libx264.a(macroblock.o): In function `x264_predict_lossless_8x8_chroma':
macroblock.c:(.text+0x3224): undefined reference to `memcpy'
macroblock.c:(.text+0x323c): undefined reference to `memcpy'
../x264/libx264.a(cabac.o): In function `x264_macroblock_write_cabac':
cabac.c:(.text+0x2c58): undefined reference to `__assert2'
cabac.c:(.text+0x2dd8): undefined reference to `__assert2'
cabac.c:(.text+0x2f80): undefined reference to `__assert2'
cabac.c:(.text+0x3020): undefined reference to `__assert2'
../x264/libx264.a(rectangle.o): In function `x264_macroblock_cache_ref_1_1':
rectangle.c:(.text+0x1e4): undefined reference to `__assert2'
../x264/libx264.a(rectangle.o):rectangle.c:(.text+0x210): more undefined references to `__assert2' follow
ERROR: libx264 not found
</pre>1.I am using fedora to build both ffmpeg and x264
2.NDK r7Any solution to successfully build the code ?