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  • Les autorisations surchargées par les plugins

    27 April 2010, by

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

  • Personnaliser les catégories

    21 June 2013, by

    Formulaire de création d’une catégorie
    Pour ceux qui connaissent bien SPIP, une catégorie peut être assimilée à une rubrique.
    Dans le cas d’un document de type catégorie, les champs proposés par défaut sont : Texte
    On peut modifier ce formulaire dans la partie :
    Administration > Configuration des masques de formulaire.
    Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
    Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...)

  • Contribute to translation

    13 April 2011

    You can help us to improve the language used in the software interface to make MediaSPIP more accessible and user-friendly. You can also translate the interface into any language that allows it to spread to new linguistic communities.
    To do this, we use the translation interface of SPIP where the all the language modules of MediaSPIP are available. Just subscribe to the mailing list and request further informantion on translation.
    MediaSPIP is currently available in French and English (...)

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  • When compressing a set of images with libx264, why does frame rate affect final output size?

    3 April 2018, by jd20

    I’m using ffmpeg to encode a set of images as a short timelapse video, using libx264 codec. My first attempt, I encoded it at 30 FPS, using:

    ffmpeg -r 30 -pattern_type glob -i "*.jpg" -vcodec libx264 -crf 30 -pix_fmt yuv420p output.mp4

    With 60 frames, that gives me a 163 KB file that’s 2 seconds long. Then I realized I needed it to be slower, so I re-ran the same command, but changed -r to 2. Now I have a file that’s 30 seconds long, but the size jumped to 891 KB! The video quality looks perceptually the same.

    How do I encode at a slower frame rate, without the final file size ballooning?

    Notes: Some theories I had, and things I checked. First, to make sure ffmpeg wasn’t duplicating frames in the longer verison, I check the I/P/B counts. The 30 FPS file had:

    [libx264 @ 0x7f9b26001c00] frame I:1     Avg QP:30.67  size: 44649
    
[libx264 @ 0x7f9b26001c00] frame P:15    Avg QP:31.19  size:  5471
    
[libx264 @ 0x7f9b26001c00] frame B:44    Avg QP:31.45  size:   767

    The 2 FPS file had:

    [libx264 @ 0x7fcd32842200] frame I:1     Avg QP:21.29  size: 90138
    
[libx264 @ 0x7fcd32842200] frame P:15    Avg QP:22.48  size: 33686
    
[libx264 @ 0x7fcd32842200] frame B:44    Avg QP:26.29  size:  6674

    So, the I/P/B counts are identical, but the QP is much lower for the 2 FPS file. To offset, I tried increasing -crf for the 2 FPS file, to get about the same target size, but that just gave me a very blurry video (had to go to crf=40). I tried messing with -minrate, -maxrate, -bt, none helped. I’m guessing there is some x264 codec setting which is frame rate dependent, but I’m at a loss trying to figure out which one (from what I understand, constant bitrate is affected by frame rate but CRF should not be, but maybe I’m misunderstanding it.

  • When compressing a set of images with libx264, why does frame rate affect final output size?

    3 April 2018, by jd20

    I’m using ffmpeg to encode a set of images as a short timelapse video, using libx264 codec. My first attempt, I encoded it at 30 FPS, using:

    ffmpeg -r 30 -pattern_type glob -i "*.jpg" -vcodec libx264 -crf 30 -pix_fmt yuv420p output.mp4

    With 60 frames, that gives me a 163 KB file that’s 2 seconds long. Then I realized I needed it to be slower, so I re-ran the same command, but changed -r to 2. Now I have a file that’s 30 seconds long, but the size jumped to 891 KB! The video quality looks perceptually the same.

    How do I encode at a slower frame rate, without the final file size ballooning?

    Notes: Some theories I had, and things I checked. First, to make sure ffmpeg wasn’t duplicating frames in the longer verison, I check the I/P/B counts. The 30 FPS file had:

    [libx264 @ 0x7f9b26001c00] frame I:1     Avg QP:30.67  size: 44649
    
[libx264 @ 0x7f9b26001c00] frame P:15    Avg QP:31.19  size:  5471
    
[libx264 @ 0x7f9b26001c00] frame B:44    Avg QP:31.45  size:   767

    The 2 FPS file had:

    [libx264 @ 0x7fcd32842200] frame I:1     Avg QP:21.29  size: 90138
    
[libx264 @ 0x7fcd32842200] frame P:15    Avg QP:22.48  size: 33686
    
[libx264 @ 0x7fcd32842200] frame B:44    Avg QP:26.29  size:  6674

    So, the I/P/B counts are identical, but the QP is much lower for the 2 FPS file. To offset, I tried increasing -crf for the 2 FPS file, to get about the same target size, but that just gave me a very blurry video (had to go to crf=40). I tried messing with -minrate, -maxrate, -bt, none helped. I’m guessing there is some x264 codec setting which is frame rate dependent, but I’m at a loss trying to figure out which one (from what I understand, constant bitrate is affected by frame rate but CRF should not be, but maybe I’m misunderstanding it.

  • Anomalie #4189 (Fermé): extraire_multi mélange un /li /ul final avec le de langue ajouté p...

    8 March 2021, by cedric -

    intégré par https://git.spip.net/spip/spip/commit/2731ba05209cf61588923a5cd8cc4442cad6878e alea jacta est

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