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  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • Support audio et vidéo HTML5

    10 avril 2011

    MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
    Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
    Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
    Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

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  • How to set PSNR value, also what is the minimum PSNR value which shows no visible artifact (no visible distortion)

    20 août 2015, par mrana

    I have 2 issues to ask :
    Q# 1. I have resized the video from 1920x1080 to 480:270 (good ratio 16:9) losslessly by the following command : ffmpeg -f rawvideo -pix_fmt yuv422p -s:v 1920x1080 -r 25 -i above_marathon_250.yuv -c:v libx264 -vf scale=480:270 -qp 0 above_marathon_250.mp4
    Once i am trying to find the PSNR value using the following command : ffmpeg -f rawvideo -pix_fmt yuv422p -s:v 1920x1080 -r 25 -i above_marathon_250.yuv -i above_marathon_250.mp4 -lavfi psnr -f null -

    I am getting the following problem : https://www.dropbox.com/s/h2djohk3d3q6uj6/Screen%20Shot%202015-08-20%20at%2018.43.24.png?dl=0

    Q# 2. What is the minimum value of PSNR for no visible artifact(no visible distortion), and how can i set it with the above command ?

    Thanks so much.

  • minimum set of required Atoms/Boxes for mpeg-4 container with H.264 (one stream, progressive video, without audio)

    3 juin 2022, par goe1zorbey

    I need to encapsulate H.264 video into a mpeg-4 container. What are the absolute minimum set of boxes/atoms do I need to have ? 
Contained H.264 video is progressive, containing 30fps video, YUV420p, without audio, no subtitles, no program information. Only one stream. No performance or file size optimization required.
It will be non-fragmented mp4 for the time being. 
Would it make things simpler to have it fragmented ? performance can be modest.

    


  • avconv / ffmpeg webcam capture while using minimum CPU processing

    10 septembre 2015, par user3585723

    I have a question about avconv (or ffmpeg) usage.

    My goal is to capture video from a webcam and saving it to a file.
    Also, I don’t want to use too much CPU processing. (I don’t want avconv to scale or re-encode the stream)

    So, I was thinking to use the compressed mjpeg video stream from the webcam and directly saving it to a file.

    My webcam is a Microsoft LifeCam HD 3000 and its capabilities are :

    ffmpeg -f v4l2 -list_formats all -i /dev/video0
    

    
Raw: yuyv422 : YUV 4:2:2 (YUYV) : 640x480 1280x720 960x544 800x448 640x360 424x240 352x288 320x240 800x600 176x144 160x120 1280x800
    

    
Compressed: mjpeg : MJPEG : 640x480 1280x720 960x544 800x448 640x360 800x600 416x240 352x288 176x144 320x240 160x120

    What would be the avconv command to save the Compressed stream directly without having avconv doing scaling or re-encoding.

    For now, I am using this command :

    avconv -f video4linux2 -r 30 -s 320x240 -i /dev/video0 test.avi

    I’m not sure that this command is CPU efficient since I don’t tell anywhere to use the mjpeg Compressed capability of the webcam.

    Is avconv taking care of the configuration of the webcam setting before starting to record the file ? Is it always working of raw stream and doing scaling and enconding on the raw stream ?

    Thanks for your answer

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