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  • Installation en mode ferme

    4 février 2011, par

    Le mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
    C’est la méthode que nous utilisons sur cette même plateforme.
    L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
    Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...)

  • Multilang : améliorer l’interface pour les blocs multilingues

    18 février 2011, par

    Multilang 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.

  • Configuration spécifique d’Apache

    4 février 2011, par

    Modules spécifiques
    Pour la configuration d’Apache, il est conseillé d’activer certains modules non spécifiques à MediaSPIP, mais permettant d’améliorer les performances : mod_deflate et mod_headers pour compresser automatiquement via Apache les pages. Cf ce tutoriel ; mode_expires pour gérer correctement l’expiration des hits. Cf ce tutoriel ;
    Il est également conseillé d’ajouter la prise en charge par apache du mime-type pour les fichiers WebM comme indiqué dans ce tutoriel.
    Création d’un (...)

Sur d’autres sites (6783)

  • Adding Documentation of a library to manual pages

    30 juin 2017, par jsp99

    I am working with Ubuntu 12.04.1 . I am learning to make a basic video player using FFmpeg library in C . My manual pages don’t show any entries for the headers/functions of the library . Can someone please show me a way to add the documentation to my manual pages .
    It is much easy to search that way than searching on a web page everytime .

    PS : I have tried to add documentation to man pages using Synaptic package manager . I installed a ffmpeg-doc package . But it doesn’t seem to work .

    Thanks .

  • ffmpeg capture output from child window

    3 janvier 2013, par glitchyme

    using xwininfo -all I'm able to see the stats of any window, along with its child windows

    xwininfo: Window id: 0x3c000ba "Electro - The Slag & Prototype Raptor - Crescendo - YouTube - Mozilla Firefox"
    

    
  Root window id: 0xa8 (the root window) (has no name)
    
  Parent window id: 0xc001b8 (has no name)
    
     2 children:
    
     0x3c00175 (has no name): ()  1388x876+0+0  +52+24
    
        5 children:
    
        0x3d210ab (has no name): ()  854x510+225+197  +277+221
    
           1 child:
    
           0x3d210ac (has no name): ()  854x510+0+0  +277+221
    
              1 child:
    
              0x40404de "plugin-container": ("plugin-container" "Plugin-container")  854x510+0+0  +277+221
    
                 2 children:
    
                 0x40404e1 (has no name): ()  854x510+0+0  +277+221
    
                 0x40404df (has no name): ()  1x1+-1+-1  +276+220
    
        0x3ddbcf2 (has no name): ()  640x390+225+162  +277+186
    
           1 child:
    
           0x3ddbcf3 (has no name): ()  640x390+0+0  +277+186
    
              1 child:
    
              0x403d545 "plugin-container": ("plugin-container" "Plugin-container")  640x390+0+0  +277+186
    
                 2 children:
    
                 0x403d548 (has no name): ()  640x390+0+0  +277+186
    
                 0x403d546 (has no name): ()  1x1+-1+-1  +276+185
    
        0x3dac7f9 (has no name): ()  640x390+225+162  +277+186
    
           1 child:
    
           0x3dac7fa (has no name): ()  640x390+0+0  +277+186
    
              1 child:
    
              0x4039d8b "plugin-container": ("plugin-container" "Plugin-container")  640x390+0+0  +277+186
    
                 2 children:
    
                 0x4039d8e (has no name): ()  640x390+0+0  +277+186
    
                 0x4039d8c (has no name): ()  1x1+-1+-1  +276+185
    
        0x3c3f939 (has no name): ()  640x390+225+197  +277+221
    
           1 child:
    
           0x3c3f93a (has no name): ()  640x390+0+0  +277+221
    
              1 child:
    
              0x4011918 "plugin-container": ("plugin-container" "Plugin-container")  640x390+0+0  +277+221
    
                 2 children:
    
                 0x401191b (has no name): ()  640x390+0+0  +277+221
    
                 0x4011919 (has no name): ()  1x1+-1+-1  +276+220
    
        0x3c0d1dc (has no name): ()  1x1+0+97  +52+121
    
           1 child:
    
           0x3c0d1dd (has no name): ()  1x1+0+0  +52+121
    
              1 child:
    
              0x4002c1e "plugin-container": ("plugin-container" "Plugin-container")  1x1+0+0  +52+121
    
                 2 children:
    
                 0x4002c40 (has no name): ()  1x1+0+0  +52+121
    
                 0x4002c1f (has no name): ()  1x1+-1+-1  +51+120
    
     0x3c000bb (has no name): ()  1x1+-1+-1  +51+23
    

    
  Absolute upper-left X:  52
    
  Absolute upper-left Y:  24
    
  Relative upper-left X:  0
    
  Relative upper-left Y:  0
    
  Width: 1388
    
  Height: 876
    
  Depth: 24
    
  Visual: 0x23
    
  Visual Class: TrueColor
    
  Border width: 0
    
  Class: InputOutput
    
  Colormap: 0x20 (installed)
    
  Bit Gravity State: NorthWestGravity
    
  Window Gravity State: NorthWestGravity
    
  Backing Store State: NotUseful
    
  Save Under State: no
    
  Map State: IsViewable
    
  Override Redirect State: no
    
  Corners:  +52+24  -0+24  -0-0  ç0
    
  -geometry 1388x876-0-0
    

    
  Bit gravity: NorthWestGravity
    
  Window gravity: NorthWestGravity
    
  Backing-store hint: NotUseful
    
  Backing-planes to be preserved: 0xffffffff
    
  Backing pixel: 0
    
  Save-unders: No
    

    
  Someone wants these events:
    
      KeyPress
    
      KeyRelease
    
      ButtonPress
    
      ButtonRelease
    
      EnterWindow
    
      LeaveWindow
    
      PointerMotion
    
      Exposure
    
      VisibilityChange
    
      StructureNotify
    
      FocusChange
    
      PropertyChange
    
  Do not propagate these events:
    
  Override redirection?: No
    

    
  Window manager hints:
    
      Client accepts input or input focus: Yes
    
      Initial state is Normal State
    
      Displayed on desktop 0
    
      Window type:
    
          Normal
    
      Window state:
    
          Maximized Vert
    
          Maximized Horz
    
      Process id: 4087 on host jb
    
      Frame extents: 0, 0, 0, 0
    

    
  Normal window size hints:
    
      Program supplied minimum size: 18 by 97
    
      Program supplied maximum size: 1073741824 by 1073741824
    
      Program supplied window gravity: NorthWestGravity
    
  No zoom window size hints defined
    

    
  No window shape defined
    
  No border shape defined

    However, if I try capturing from the screen given the size and offset of the child window, then I risk losing data when another window floats ontop of it, I switch to another tab while recording, I resize the child window, or move the child window. Instead, I'd like to use ffmpeg to capture from specifically that child window.

    Ideas ? Tips ? Maybe some other hacks to accomplish this ? Thanks :)

  • Making Sure The PNG Gets There

    14 juin 2013, par Multimedia Mike — General

    Rewind to 1999. I was developing an HTTP-based remote management interface for an embedded device. The device sat on an ethernet LAN and you could point a web browser at it. The pitch was to transmit an image of the device’s touch screen and the user could click on the picture to interact with the device. So we needed an image format. If you were computing at the time, you know that the web was insufferably limited back then. Our choice basically came down to GIF and JPEG. Being the office’s annoying free software zealot, I was championing a little known up and coming format named PNG.

    So the challenge was to create our own PNG encoder (incorporating a library like libpng wasn’t an option for this platform). I seem to remember being annoyed at having to implement an integrity check (CRC) for the PNG encoder. It’s part of the PNG spec, after all. It just seemed so redundant. At the time, I reasoned that there were 5 layers of integrity validation in play.

    I don’t know why, but I was reflecting on this episode recently and decided to revisit it. Here are all the encapsulation layers of a PNG file when flung over an ethernet network :


    PNG Network Encapsulation

    So there are up to 5 encapsulations for the data in this situation. At the innermost level is the image data which is compressed with the zlib DEFLATE method. At first, I thought that this also had a CRC or checksum. However, in researching this post, I couldn’t find any evidence of such an integrity check. Further, I don’t think we bothered to compress the PNG data in this project long ago. It was a small image, monochrome, and transferring via LAN, so the encoder could get away with signaling uncompressed data.

    The graphical data gets wrapped up in a PNG chunk and all PNG chunks have a CRC. To transmit via the network, it goes into a TCP frame, which also has a checksum. That goes into an IP packet. I previously believed that this represented another integrity check. While an IP frame does have a checksum, the checksum only covers the IP header and not the payload. So that doesn’t really count towards this goal.

    Finally, the data gets encapsulated into an ethernet frame which has — you guessed it — a CRC.

    I see that other link layer protocols like PPP and wireless ethernet (802.11) also feature frame CRCs. So I guess what I’m saying is that, if you transfer a PNG file over the network, you can be confident that the data will be free of any errors.

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