Recherche avancée

Médias (0)

Mot : - Tags -/formulaire

Aucun média correspondant à vos critères n’est disponible sur le site.

Autres articles (78)

  • La sauvegarde automatique de canaux SPIP

    1er avril 2010, par

    Dans 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, par

    Afin 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 (...)

  • Automated installation script of MediaSPIP

    25 avril 2011, par

    To overcome the difficulties mainly due to the installation of server side software dependencies, an "all-in-one" installation script written in bash was created to facilitate this step on a server with a compatible Linux distribution.
    You must have access to your server via SSH and a root account to use it, which will install the dependencies. Contact your provider if you do not have that.
    The documentation of the use of this installation script is available here.
    The code of this (...)

Sur d’autres sites (6042)

  • speeding up x264 encoding (C++ code with libavcodec)

    20 décembre 2012, par Hrishikesh_Pardeshi

    I am trying to capture windows screen (continuous screen shots) and encode them into x264. For that I am using avcodec_encode_video2 function available with libavcodec. However, it takes a huge amount of time. The time fluctuates between 25 – 1800 milliseconds for encoding individual frames.

    I tried tried both 1080p and 720p with video recording on screen.

    These are the settings I am using. This was tested on Windows 7, win32 release build with 4 GB of RAM.

    bit_rate = 2000, width = 1920, height = 1080
    qmin = 0, qmax = 0, max_b_frames = 0, frame_rate = 25, pixel_format = YUV 4:4:4.
    The remaining settings are default which are fetched using avcodec_get_context_defaults3().

    Sample data(in milliseconds) for 20 frames (consecutive and chosen randomly) in a set of 250 frames.
    121, 106, 289, 126, 211, 30, 181, 58, 213, 34, 245, 50, 56, 364, 247, 171, 254, 83, 82, 229

    For the application it is a must that it captures at least at 15 fps. Can someone help out to tell whether any options can be used to improve the frame rate. I need to encode lossless, but I am open to some file size increase.

    Thanks in advance.

  • speeding up x264 encoding (C++ code with libavcodec)

    20 décembre 2012, par Hrishikesh_Pardeshi

    I am trying to capture windows screen (continuous screen shots) and encode them into x264. For that I am using avcodec_encode_video2 function available with libavcodec. However, it takes a huge amount of time. The time fluctuates between 25 – 1800 milliseconds for encoding individual frames.

    I tried tried both 1080p and 720p with video recording on screen.

    These are the settings I am using. This was tested on Windows 7, win32 release build with 4 GB of RAM.

    bit_rate = 2000, width = 1920, height = 1080
    qmin = 0, qmax = 0, max_b_frames = 0, frame_rate = 25, pixel_format = YUV 4:4:4.
    The remaining settings are default which are fetched using avcodec_get_context_defaults3().

    Sample data(in milliseconds) for 20 frames (consecutive and chosen randomly) in a set of 250 frames.
    121, 106, 289, 126, 211, 30, 181, 58, 213, 34, 245, 50, 56, 364, 247, 171, 254, 83, 82, 229

    For the application it is a must that it captures at least at 15 fps. Can someone help out to tell whether any options can be used to improve the frame rate. I need to encode lossless, but I am open to some file size increase.

    Thanks in advance.

  • How to extract raw YUV files from MPEG2 TS file ?

    11 septembre 2012, par Wang Wei

    I have a 1920x1080 mpeg2 .ts file. I need to get the raw YUV files for each frame.
    I tried ffmpeg but no luck. I end up with many small files. I expect each frame to be 1920x1080x1.5 = 3110400 Bytes.

    [root@dwarch frames]# ffmpeg -i video.ts -f image2 foo-%03d.yuv
    
FFmpeg version git-N-28713-g65daa94, Copyright (c) 2000-2011 the FFmpeg developers
    
  built on Mar 30 2011 09:20:16 with gcc 4.6.0
    
  configuration: --prefix=/usr --enable-gpl --enable-libmp3lame --enable-libvorbis --enable-libfaac --enable-libxvid --enable-libx264 --enable-libvpx --enable-libtheora --enable-postproc --enable-shared --enable-x11grab --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libschroedinger --enable-libopenjpeg --enable-version3 --enable-nonfree --enable-runtime-cpudetect --disable-debug
    
  libavutil    50. 40. 0 / 50. 40. 0
    
  libavcodec   52.116. 0 / 52.116. 0
    
  libavformat  52.104. 0 / 52.104. 0
    
  libavdevice  52.  4. 0 / 52.  4. 0
    
  libavfilter   1. 76. 0 /  1. 76. 0
    
  libswscale    0. 13. 0 /  0. 13. 0
    
  libpostproc  51.  2. 0 / 51.  2. 0
    
Input #0, mpegts, from 'video.ts':
    
  Duration: 00:04:51.58, start: 0.333333, bitrate: 36041 kb/s
    
  Program 10 
    
    Stream #0.0[0x20]: Video: mpeg2video (Main), yuv420p, 1920x1080 [PAR 1:1 DAR 16:9], 35000 kb/s, 23.98 fps, 23.98 tbr, 90k tbn, 47.95 tbc
    
    Stream #0.1[0x21]: Audio: ac3, 48000 Hz, 5.1, s16, 224 kb/s
    
Incompatible pixel format 'yuv420p' for codec 'mjpeg', auto-selecting format 'yuvj420p'
    
[buffer @ 0x97148c0] w:1920 h:1080 pixfmt:yuv420p
    
[setdar @ 0x9714df0] a:16/9
    
[setdar @ 0x9714df0] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'Parsed filter 0 setdar'
    
[scale @ 0x9711db0] w:1920 h:1080 fmt:yuv420p -> w:1920 h:1080 fmt:yuvj420p flags:0x4
    
[setdar @ 0x9714df0] w:1920 h:1080 -> dar:16/9 sar:1/1
    
Output #0, image2, to 'foo-%03d.yuv':
    
  Metadata:
    
    encoder         : Lavf52.104.0
    
    Stream #0.0: Video: mjpeg, yuvj420p, 1920x1080 [PAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 90k tbn, 23.98 tbc
    
Stream mapping:
    
  Stream #0.0 -> #0.0

Navigation