Recherche avancée

Médias (1)

Mot : - Tags -/wave

Autres articles (57)

  • 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 (...)

  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

Sur d’autres sites (14937)

  • Is it possible to "lossless"-ly speed up a video ?

    15 novembre 2020, par Synn Ko

    Might sound like a strange question, but hear me out. I have hours of video I want to cut up and edit together, but a lot of it is just junk I don't need. I don't want to lose any quality, so I use LosslessCut.

    


    The problem for me is that it's... A LOT of footage, and I don't need to see every single second of it. It would be nice if LosslessCut had a button to change the speed of the playback, but it doesn't have that.

    


    So another idea would be to speed up all the videos in advance with ffmpeg, cut them up using LosslessCut, then change the remaining clips back to their original speed using ffmpeg again. Is it possible to speed up a video and change it back to its original speed without losing any quality or changing the video ?

    


  • ffmpeg distributed transcoding

    23 juillet 2020, par Kalava

    I have a 100GB 1080p video file which I want to transcode to 720 h264. Since transcoding is computationally expensive, i wanted to transcode smaller portions of video & stitch it back together. Can we use ffmpeg seek to transcode 10seconds of video & stitch it back together ? When I am reading through blogs they mention to go with GOP. I want to get opinion with below approach. Any help is appreciated.

    


    ffmpeg -ss 00:00:00 -i 80Gb.mp4 -t 10  -s 720x720 -c:v libx264 -c:a aac chunk1.mp4 
ffmpeg -ss 00:00:10 -i 80Gb.mp4 -t 10 -s 720x720 -c:v libx264 -c:a aac chunk2.mp4
ffmpeg -ss 00:00:20 -i 80Gb.mp4 -t 10 -s 720x720 -c:v libx264 -c:a aac chunk2.mp4


    


    ...

    


  • ffmpeg change framerate : Question about bitrate [closed]

    9 février, par schweigerson

    Thanks to the forum, I successfully can reduce the frame rate of a video.

    


    ffmpeg -i input_50fps.mp4 -filter:v fps=25 output_25fps.mp4

    


    Input and output have a similar bitrate as well as filzesize :

    


    




    


    


    


    


    


    



    


    


    


    


    


    


    


    


    


    


    File bitrate filesize
    input_50fps.mp4 2900kBit/s 1.9GB
    output_25fps.mp4 2528kBit/s 1.7GB

    


    Assumption : Divide the number of frames into half should both reduce the bitrate and the filesize accordingly (half the size).

    


    Question : Does it make sense to enforce the reduction of the bitrate to approx. half the original one, when I reduce the framerate by to 50% (e.g. with -b:v 1500k) ? IMHO, the video quality should be comparable to the original video then.

    


    Note : I may make according test runs, but I perhaps do not have the ability to recognize the quality difference as I'm not an advanced video expert.

    


    Would be happy to read your advice.

    


Navigation