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  • L’espace de configuration de MediaSPIP

    29 novembre 2010, par

    L’espace de configuration de MediaSPIP est réservé aux administrateurs. Un lien de menu "administrer" est généralement affiché en haut de la page [1].
    Il permet de configurer finement votre site.
    La navigation de cet espace de configuration est divisé en trois parties : la configuration générale du site qui permet notamment de modifier : les informations principales concernant le site (...)

  • Déploiements possibles

    31 janvier 2010, par

    Deux types de déploiements sont envisageable dépendant de deux aspects : La méthode d’installation envisagée (en standalone ou en ferme) ; Le nombre d’encodages journaliers et la fréquentation envisagés ;
    L’encodage de vidéos est un processus lourd consommant énormément de ressources système (CPU et RAM), il est nécessaire de prendre tout cela en considération. Ce système n’est donc possible que sur un ou plusieurs serveurs dédiés.
    Version mono serveur
    La version mono serveur consiste à n’utiliser qu’une (...)

  • Submit bugs and patches

    13 avril 2011

    Unfortunately a software is never perfect.
    If you think you have found a bug, report it using our ticket system. Please to help us to fix it by providing the following information : the browser you are using, including the exact version as precise an explanation as possible of the problem if possible, the steps taken resulting in the problem a link to the site / page in question
    If you think you have solved the bug, fill in a ticket and attach to it a corrective patch.
    You may also (...)

Sur d’autres sites (5680)

  • FFmpeg - selecting appropriate bitrate for VP9 encoding

    6 avril 2017, par fastily

    I am looking to encode a 4k video shot with iPhone 6s in VP9 in the best quality possible.

    For reference, stream data of the video I would like to encode, via ffprobe :

    Duration: 00:00:10.48, start: 0.000000, bitrate: 46047 kb/s
    
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 3840x2160, 45959 kb/s, 29.98 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler
    
      encoder         : H.264
    
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 79 kb/s (default)
    
    Metadata:
    
      creation_time   : 2017-03-13T21:12:56.000000Z
    
      handler_name    : Core Media Data Handler

    I am using the following FFmpeg commands, based on these instructions (see Best Quality (Slowest) Recommended Settings section).

    1. ffmpeg -i INPUT.mov -c:v libvpx-vp9 -pass 1 -b:v 46000K -threads 4 -speed 4 -g 9999 -an -f webm -y /dev/null
    2. ffmpeg -I INPUT.mov -c:v libvpx-vp9 -pass 2 -b:v 46000K -threads 4 -speed 0 -g 9999 -an -f webm OUTPUT.webm

    Is there a best practice to select an optimal -b:v value such that the resulting video is visually indistinguishable from the original ? I have tried values ranging from 36000K-46000K, but these result in massive files with an overall bitrate exceeding the target bitrate.

    Thanks in advance !

  • ffmpeg override the same file for every second of the video [on hold]

    5 février 2017, par Dorin Pleava

    I want to get one image for every 10 seconds from a livestream/video, but the image should have the same name, meaning I want to override it every cycle.

    This is my command :

    ffmpeg.exe -i http://iphone-streaming.ustream.tv/uhls/17074538/streams/live/iphone/playlist.m3u8 -bt 20M -s 480x300 -vf fps=1/10 -y photo.jpg

    This code works for one image but for the next I get this

    "Could not get frame filename number 2 from pattern ’photo.jpg’ (either set updatefirst or use a pattern like %03d within the filename pattern)
    av_interleaved_write_frame() : Invalid argument"

    If I replace photo.jpeg with photo%03d.jpg I get photo001.jpec, followed by photo002.jpeg, etc.

  • How to extract orientation information from videos ?

    23 décembre 2016, par Sid

    After surfing through tons of documentation on the web it seems that the iPhone always shoots the video at a 480x360 aspect ratio and applies a transformation matrix on the video track. (480x360 may change but its always the same for a given device)

    Here is a way of modifying the ffmpeg source within a iOS project and accessing the matrix http://www.seqoy.com/correct-orientation-for-iphone-recorded-movies-with-ffmpeg/

    Here is a cleaner way of finding the transformation matrix in iOS-4
    how to detect (iphone sdk) if a video file was recorded in portrait orientation, or landscape

    How can the orientation of the video be extracted in either of the options below -

    - iOS 3.2

    - ffmpeg (through the command line server side)

    - ruby

    Any help will be appreciated.

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