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Richard Stallman et le logiciel libre
19 octobre 2011, par
Mis à jour : Mai 2013
Langue : français
Type : Texte
Autres articles (97)
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MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...) -
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. -
Keeping control of your media in your hands
13 avril 2011, parThe vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)
Sur d’autres sites (11405)
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ffmpeg rtmp streaming process exit
12 août 2013, par SamsonI'm using ffmpeg to capture jpeg images from an rtmp stream. Here is the command I use :
/usr/local/bin/ffmpeg -threads 4 -i rtmp://..../chat/mp4:<variable>.mp4
-q:v 0.6 -r 15 -s 320x240 /frames/10021237_data/frame-%0999d.jpg
ffmpeg version N-55388-g9386f33 Copyright (c) 2000-2013 the FFmpeg developers
built on Aug 8 2013 14:07:38 with gcc 4.7 (Ubuntu/Linaro 4.7.2-2ubuntu1)
configuration:
libavutil 52. 41.100 / 52. 41.100
libavcodec 55. 24.100 / 55. 24.100
libavformat 55. 13.102 / 55. 13.102
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 82.100 / 3. 82.100
libswscale 2. 4.100 / 2. 4.100
libswresample 0. 17.103 / 0. 17.103
Input #0, flv, from 'rtmp://......./mp4:10021237.mp4':
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0:0: Video: h264 (Main), yuv420p, 640x480 [SAR 1:1 DAR 4:3], 1.92 tbr, 1k tbn, 40 tbc
Stream #0:1: Audio: nellymoser, 44100 Hz, mono, flt
[swscaler @ 0x1910000] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to '/frames/10021237_data/frame-%0999d.jpg':
Metadata:
encoder : Lavf55.13.102
Stream #0:0: Video: mjpeg, yuvj420p, 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 90k tbn, 15 tbc
Stream mapping:
Stream #0:0 -> #0:0 (h264 -> mjpeg)
Press [q] to stop, [?] for help
</variable>However after a few minutes I get this line (before the process exits) :
video:5264kB audio:0kB subtitle:0 global headers:0kB muxing overhead -100.000408%
What exactly is the "muxing overhead" and why is it causing a crash ? Can I solve this or get it some other way (by restarting the process when it exits) ?
EDIT :
Actually it's not a crash. I'm running this command from a PHP CLI when a stream starts :
$command = "/usr/local/bin/ffmpeg -i ".$rtmp." -q:v 0.6 -r 12 -s 320x240 ".__DIR__."/".$dir."/".$naming." >/dev/null 2>/dev/null &";
shell_exec($command);but when one stops streaming all the ffmpeg processes end. Is there a way to make them independent ?
Even opening 2 terminals and running the command (with different rtmp s)in each (for different streams), killing one of them closes the other one also.
Bottom line is : How can I make 2 ffmpeg instances independent so as killing one does not kill the other. Is this behaviour expected ?
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How to detect audio sampling rate with avprobe / ffprobe ?
8 août 2013, par DevyI am using libav 9.6, installed via Homebrew.
$ avprobe -version
avprobe version 9.6, Copyright (c) 2007-2013 the Libav developers
built on Jun 8 2013 02:44:19 with Apple LLVM version 4.2 (clang-425.0.24) (based on LLVM 3.2svn)
avprobe 9.6
libavutil 52. 3. 0 / 52. 3. 0
libavcodec 54. 35. 0 / 54. 35. 0
libavformat 54. 20. 3 / 54. 20. 3
libavdevice 53. 2. 0 / 53. 2. 0
libavfilter 3. 3. 0 / 3. 3. 0
libavresample 1. 0. 1 / 1. 0. 1
libswscale 2. 1. 1 / 2. 1. 1Even though the sampling rate is displayed in the stdout in the command line output, the
-show_format
option doesn't surface the sampling rate information for the audio file at all.Here is the BASH terminal output :
$ avprobe -v verbose -show_format -of json sample.gsm
avprobe version 9.6, Copyright (c) 2007-2013 the Libav developers
built on Jun 8 2013 02:44:19 with Apple LLVM version 4.2 (clang-425.0.24)
(based on LLVM 3.2svn)
configuration: --prefix=/usr/local/Cellar/libav/9.6 --enable-shared
--enable-pthreads --enable-gpl --enable-version3 --enable-nonfree
--enable-hardcoded-tables --enable-avresample --enable-vda --enable-gnutls
--enable-runtime-cpudetect --disable-indev=jack --cc=cc --host-cflags=
--host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame
--enable-libxvid --enable-avplay
libavutil 52. 3. 0 / 52. 3. 0
libavcodec 54. 35. 0 / 54. 35. 0
libavformat 54. 20. 3 / 54. 20. 3
libavdevice 53. 2. 0 / 53. 2. 0
libavfilter 3. 3. 0 / 3. 3. 0
libavresample 1. 0. 1 / 1. 0. 1
libswscale 2. 1. 1 / 2. 1. 1
[gsm @ 0x7f8012806600] Estimating duration from bitrate, this may be inaccurate
Input #0, gsm, from 'sample.gsm':
Duration: 00:03:52.32, start: 0.000000, bitrate: 13 kb/s
Stream #0.0: Audio: gsm, 8000 Hz, mono, s16, 13 kb/s
{ "format" : {
"filename" : "sample.gsm",
"nb_streams" : 1,
"format_name" : "gsm",
"format_long_name" : "raw GSM",
"start_time" : "0.000000",
"duration" : "232.320000",
"size" : "383328.000000",
"bit_rate" : "13200.000000"
}}And the python code example :
>>> filename = 'sample.gsm'
>>> result = subprocess.check_output(['avprobe', '-show_format', '-of',
'json', filename])
avprobe version 9.6, Copyright (c) 2007-2013 the Libav developers
built on Jun 8 2013 02:44:19 with Apple LLVM version 4.2
(clang-425.0.24) (based on LLVM 3.2svn)
[gsm @ 0x7fe0b1806600] Estimating duration from bitrate, this may be
inaccurate
Input #0, gsm, from 'sample.gsm':
Duration: 00:03:52.32, start: 0.000000, bitrate: 13 kb/s
Stream #0.0: Audio: gsm, 8000 Hz, mono, s16, 13 kb/s
>>> print result
{ "format" : {
"filename" : "sample.gsm",
"nb_streams" : 1,
"format_name" : "gsm",
"format_long_name" : "raw GSM",
"start_time" : "0.000000",
"duration" : "232.320000",
"size" : "383328.000000",
"bit_rate" : "13200.000000"
}}So I am aware that sampling rate could be a stream specific display to be shown in
-show_format
option results. But there isn't any other options to detect the sampling rate on a specific audio stream even though it's possible to set it with-ar
when re-encoding it.I filed a ticket to libav but I am just curious if there is any other way to extract sampling rate from libav probing utils. I appreciate the answer beforehand.
PS : it would be the same question for the upstream project of ffmpeg (ffprobe) in this case.
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webm to mp4 conversion using ffmpeg
2 décembre 2015, par Pavan KWhen I try to convert a webm file to mp4 the output is very very choppy and it appears as if many frames have been dropped by ffmpeg
I used the following commands to convert
ffmpeg -i movie.webm movie.mp4
ffmpeg -i movie.webm -vcodec libx264 movie.mp4
ffmpeg -i movie.webm -vcodec libx264 -qscale 0 movie.mp4All of them have the same problem. When I use ffprobe it seems to show the frames more or less properly.
UPDATE :
built on Jun 14 2013 14:31:50 with gcc 4.7 (Ubuntu/Linaro 4.7.2-2ubuntu1)
configuration: --prefix=/home/user2/ffmpeg_build --extra-cflags=-I/home/user2/ffmpeg_build/include --extra-ldflags=-L/home/pavan4/ffmpeg_build/lib --bindir=/home/pavan4/bin --extra-libs=-ldl --enable-gpl --enable-libass --enable-libfdk-aac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree --enable-x11grab
libavutil 52. 35.101 / 52. 35.101
libavcodec 55. 16.100 / 55. 16.100
libavformat 55. 8.102 / 55. 8.102
libavdevice 55. 2.100 / 55. 2.100
libavfilter 3. 77.101 / 3. 77.101
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
Use -h to get full help or, even better, run 'man ffmpeg'
Input #0, matroska,webm, from '1.webm':
Duration: 00:00:10.64, start: 0.000000, bitrate: 5024 kb/s
Stream #0:0(eng): Video: vp8, yuv420p, 1280x720, SAR 1:1 DAR 16:9, 1k fps, 1k tbr, 1k tbn, 1k tbc (default)
[libx264 @ 0x1d966a0] using SAR=1/1
[libx264 @ 0x1d966a0] MB rate (3600000) > level limit (2073600)
[libx264 @ 0x1d966a0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2
[libx264 @ 0x1d966a0] profile High, level 5.2
[libx264 @ 0x1d966a0] 264 - core 133 r2 a3ac64b - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 - 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=12 lookahead_threads=2 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 '1_conv4.mp4':
Metadata:
encoder : Lavf55.8.102
Stream #0:0(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 16k tbn, 1k tbc (default)
Stream mapping:
Stream #0:0 -> #0:0 (vp8 -> libx264)
Press [q] to stop, [?] for help
frame= 168 fps=0.0 q=33.0 size= 62kB time=00:00:00.11 bitrate=4606.0kbits/frame= 293 fps=230 q=33.0 size= 138kB time=00:00:00.23 bitrate=4809.7kbits/
video:5620kB audio:0kB subtitle:0 global headers:0kB muxing overhead 2.212461%
[libx264 @ 0x1d966a0] frame I:46 Avg QP:18.50 size: 39849
[libx264 @ 0x1d966a0] frame P:2940 Avg QP:18.27 size: 1222
[libx264 @ 0x1d966a0] frame B:7651 Avg QP:17.68 size: 43
[libx264 @ 0x1d966a0] consecutive B-frames: 4.0% 0.2% 0.3% 95.5%
[libx264 @ 0x1d966a0] mb I I16..4: 19.9% 63.2% 16.9%
[libx264 @ 0x1d966a0] mb P I16..4: 0.2% 0.5% 0.1% P16..4: 3.9% 1.1% 0.6% 0.0% 0.0% skip:93.6%
[libx264 @ 0x1d966a0] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 0.2% 0.0% 0.0% direct: 0.0% skip:99.8% L0:25.1% L1:74.9% BI: 0.0%
[libx264 @ 0x1d966a0] 8x8 transform intra:63.6% inter:75.9%
[libx264 @ 0x1d966a0] coded y,uvDC,uvAC intra: 61.5% 53.4% 24.4% inter: 0.5% 0.5% 0.0%
[libx264 @ 0x1d966a0] i16 v,h,dc,p: 52% 19% 19% 11%
[libx264 @ 0x1d966a0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 32% 17% 13% 4% 6% 9% 5% 8% 6%
[libx264 @ 0x1d966a0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 30% 18% 14% 5% 8% 10% 6% 6% 3%
[libx264 @ 0x1d966a0] i8c dc,h,v,p: 55% 17% 24% 4%
[libx264 @ 0x1d966a0] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x1d966a0] ref P L0: 82.5% 13.2% 4.0% 0.3%
[libx264 @ 0x1d966a0] ref B L0: 60.2% 39.2% 0.6%
[libx264 @ 0x1d966a0] ref B L1: 98.5% 1.5%
[libx264 @ 0x1d966a0] kb/s:4327.77