
Recherche avancée
Autres articles (94)
-
MediaSPIP Core : La Configuration
9 novembre 2010, parMediaSPIP Core fournit par défaut trois pages différentes de configuration (ces pages utilisent le plugin de configuration CFG pour fonctionner) : une page spécifique à la configuration générale du squelettes ; une page spécifique à la configuration de la page d’accueil du site ; une page spécifique à la configuration des secteurs ;
Il fournit également une page supplémentaire qui n’apparait que lorsque certains plugins sont activés permettant de contrôler l’affichage et les fonctionnalités spécifiques (...) -
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 (...) -
Problèmes fréquents
10 mars 2010, parPHP et safe_mode activé
Une des principales sources de problèmes relève de la configuration de PHP et notamment de l’activation du safe_mode
La solution consiterait à soit désactiver le safe_mode soit placer le script dans un répertoire accessible par apache pour le site
Sur d’autres sites (6494)
-
ffmpeg for archival and convertibility
27 juillet 2021, par SatyaI've got a couple hundred gigs of *.dv files. I'd like to convert them to H.264 or something else or even leave them alone. The purpose is archival, with an eye to maximum convertibility especially to DVD. The content is family videos.


Would this be fine ?


ffmpeg -i input.dv \
 -c:v libx264 -preset slower \
 -crf 17 \
 -pix_fmt yuv420p \
 output.mp4



I went with the
slower
preset because encoding time isn't an issue and I'd like a smaller file size. crf 17 is for least-lossy while being widely playable. I read somewhere that yuv420p is needed for some Quicktime players.

Should I throw in
-c:a aac
for AAC audio ? The audio is voice only, no need for music-hall quality.

I looked at https://trac.ffmpeg.org/wiki/Encode/H.264 for previous research and that's where I got those settings, but it is silent on the audio settings.


Edited : My priorities, in order of importance, are :


- 

- Compatibility
- Losslessness (doesn't have to be 100% lossless, hence crf of 17 and not 0)
- File size








Most of the input files say this :


[lavf] stream 0: video (dvvideo), -vid 0
[lavf] stream 1: audio (pcm_s16le), -aid 0
VIDEO: [dvsd] 720x480 0bpp 29.970 fps 25000.0 kbps (3051.8 kbyte/s)
Selected video codec: [ffdv] vfm: ffmpeg (FFmpeg DV)
AUDIO: 32000 Hz, 2 ch, s16le, 1024.0 kbit/100.00% (ratio: 128000->128000)
Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)



Output from ffmpeg :


Stream #0:1: Audio: pcm_s16le, 32000 Hz, stereo, s16, 1024 kb/s



-
can't read mp4 in opencv3.2 (ubuntu, python3)
28 mars 2017, par lhkI’ve ran into a problem with my opencv installation, it is unable to open an mp4 video. My system is ubuntu 16.04, 64bit, opencv3.2 used from python 3.5.
VideoCapture.read
returnsFalse
andNone
.There are other questions with this problem, but they target different platforms or different opencv versions.
Apparently, I’m missing the proper codec.
So I ranmake uninstall
from my build directory, purgedopencv*
with apt and built from source again. This time making sure thatffmpeg
was installed before the compilation.Here are my steps :
- clone opencv and opencv_contrib
cd opencv/
mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D INSTALL_PYTHON_EXAMPLES=ON -D INSTALL_C_EXAMPLES=OFF -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules -D BUILD_EXAMPLES=ON ..
make -j 8
sudo make install
I checked the output of cmake, ffmpeg is there :
Video I/O:
-- DC1394 1.x: NO
-- DC1394 2.x: NO
-- FFMPEG: YES
-- avcodec: YES (ver 56.60.100)
-- avformat: YES (ver 56.40.101)
-- avutil: YES (ver 54.31.100)
-- swscale: YES (ver 3.1.101)
-- avresample: NO
-- GStreamer: NO
-- OpenNI: NO
-- OpenNI PrimeSensor Modules: NO
-- OpenNI2: NO
-- PvAPI: NO
-- GigEVisionSDK: NO
-- Aravis SDK: NO
-- UniCap: NO
-- UniCap ucil: NO
-- V4L/V4L2: NO/YES
-- XIMEA: NO
-- Xine: NO
-- gPhoto2: NOBut the problem persists. How can I fix this ?
UPDATE
I had to manually remove some .so files from /usr/local.
Then I installed all avi related codecs I could find.
https://wiki.ubuntuusers.de/Codecs/
plus libavcodec-extra and ffmpegThen I recompiled and now it works.
-
Revision 17292 : Update Skeleton/OggIndex support to Skeleton 4.0. ffmpeg2theora now ...
16 juin 2010, par j — LogUpdate Skeleton/OggIndex ? support to Skeleton 4.0.
ffmpeg2theora now writes Skeleton 4.0 with index by default.
Patch by Chris Pearce