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    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

  • Configurer la prise en compte des langues

    15 novembre 2010, par

    Accéder à la configuration et ajouter des langues prises en compte
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    De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
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  • Sélection de projets utilisant MediaSPIP

    29 avril 2011, par

    Les exemples cités ci-dessous sont des éléments représentatifs d’usages spécifiques de MediaSPIP pour certains projets.
    Vous pensez avoir un site "remarquable" réalisé avec MediaSPIP ? Faites le nous savoir ici.
    Ferme MediaSPIP @ Infini
    L’Association Infini développe des activités d’accueil, de point d’accès internet, de formation, de conduite de projets innovants dans le domaine des Technologies de l’Information et de la Communication, et l’hébergement de sites. Elle joue en la matière un rôle unique (...)

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  • FFmpeg compose, multi layers and filters, need kindly help 

    9 octobre 2019, par jadeshohy

    Pretty new to FFmpeg. We would like to use FFmpeg as a important part of an AR project.

    Currently, we find it is not easy for us.

    We want to compose the footages with FFmpeg.

    We got 5 layers, wanted to blend them with specific mode, like the things in After Effects.

    • layer-1/ [A.webm] video,vp9 codec, which has a transparent BG,has to be added as [normal mode]

    • layer-2/ [B.mp4] video, optical-flare things with black BG,has to be added as [screen mode]

    • layer-3/ [C.mp4] video, some motion graphic things with light BG,has to be added as [overlay mode]

    • layer-4/ [BG.MP4], backgound things, has to be added as [normal mode]

    After we blend those 4 (like pre-compose,use blend filter), we want to add another layer-5/[icon.png] which is the special icon.

    Layer-5 need to overlay the pre-compose. We have to overlay it at the special position (use overlay filter ?).

    Cause [icon.png] may change frequently. we want to deal with that after the 4 layer blending.

    But at the first step, when we set normal mode for layer-1 in blend filter, layer-1 [A.webm] lost the transparent BG,it gave us a black BG which block all other things.
    Blend filter can not handle the alpha channel of vp9 webm ?
    When we set the mode of layer-1 to screen mode,the translucent thing was not what we need.

    Could you please give us some commands to achieve the blend above ?

    The commands that are really work will be extremely useful for our FFmpeg initiation.

  • In ffmpeg : Can't get peak bitrate values within 10% error tolerance for HLS playlist files

    5 octobre 2019, par ALS20394

    I’m using ffmpeg to produce several HLS variant playlists from an .mp4 file. When I check master.m3u8 file with mediastreamvalidator I get :

    Error : Measured peak bitrate compared to master playlist declared value exceeds error tolerance

    I understand that the error percentage needs to be less than 10%, and figured it out on 1 variant but not the three others. I’ve spent quite a bit of time adjusting the -maxrate and the -buffsize but the error percentage change is minimal. Beginning to wonder if I’m misunderstanding something ?

    This is the latest of what I enter :

    ffmpeg -i FHVid.mp4 \
    -b:v:0 5000k -maxrate 5250k -bufsize 5500k -profile:v main -c:v h264 -crf 20 -sc_threshold 0 -g 48 \
    -b:v:1 2800k -maxrate 2940k -bufsize 3100k -profile:v main -c:v h264 -crf 20 -sc_threshold 0 -g 48 \
    -b:v:2 1400k -maxrate 1540k -bufsize 1700k -profile:v main -c:v h264 -crf 20 -sc_threshold 0 -g 48 \
    -b:v:3 800k -maxrate 840k -bufsize 1050k -profile:v main -c:v h264 -crf 20 -sc_threshold 0 -g 48 \
    -b:a:0 192k \
    -b:a:1 128k \
    -b:a:2 128k \
    -b:a:3 96k \
    -c:a aac -ar 48000 -keyint_min 48 -map 0:v -map 0:a -map 0:v -map 0:a -map 0:v -map 0:a -map 0:v -map 0:a \
    -f hls -var_stream_map "v:0,a:0  v:1,a:1 v:2,a:2 v:3,a:3" \
    -master_pl_name FHVidmaster.m3u8 -hls_time 4 -hls_playlist_type vod \
    -hls_segment_filename 'file_%v_%03d.ts' out_%v.m3u8

    but I’ve also tried max rates that seem to be more standard

    -b:v:0 5000k -maxrate 5500k -bufsize 6500k
    -b:v:1 2800k -maxrate 3080k -bufsize 3200k
    -b:v:2 1400k -maxrate 1540k -bufsize 1900k
    -b:v:3 800k -maxrate 880k -bufsize 1050k

    The latest error message :

    Error: Measured peak bitrate compared to master playlist declared value exceeds error tolerance
    --> Detail:  Measured: 1111.54 kb/s, Master playlist: 1680.80 kb/s, Error: 33.87%
    --> Source:  /Users/Bun/Documents/CODING/CosmicPerspectiveAssets/01-FalconHeavy/HLS/FHVidmaster.m3u8
    --> Compare: out_2.m3u8

    --> Detail:  Measured: 1178.21 kb/s, Master playlist: 5711.20 kb/s, Error: 79.37%
    --> Source:  /Users/Bun/Documents/CODING/CosmicPerspectiveAssets/01-FalconHeavy/HLS/FHVidmaster.m3u8
    --> Compare: out_0.m3u8

    --> Detail:  Measured: 1109.03 kb/s, Master playlist: 3220.80 kb/s, Error: 65.57%
    --> Source:  /Users/Bun/Documents/CODING/CosmicPerspectiveAssets/01-FalconHeavy/HLS/FHVidmaster.m3u8
    --> Compare: out_1.m3u8

    Any help would be greatly appreciated on the -maxrate and -buffsize for variant playlists 0, 1, and 2. No adjustment I make seems to make any difference.

  • ffmpeg add semi transparent watermark(png) with different size

    29 juillet 2020, par Archer

    I'm trying to add a png watermark (with alpha channel) over h264 video with semi transparent. By using overlay filter I managed to add watermark to the video.

    



    ffmpeg -y -i input.mp4 -i watermark.png -filter_complex "[0][1] overlay=0:0" -c:v libx264 -an output.mp4


    



    But overlay filter does not provide transparent option. So I tried to use blend filter. However, when I use origin resolution, error message comes out.

    



    ffmpeg -y -i input.mp4 -i watermark.png -filter_complex "[0][1]blend=all_mode=overlay:all_opacity=0.3" -c:v libx264 -an output.mp4


    



    Output :

    



      libavutil      55. 28.100 / 55. 28.100
  libavcodec     57. 48.101 / 57. 48.101
  libavformat    57. 41.100 / 57. 41.100
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 47.100 /  6. 47.100
  libavresample   3.  0.  0 /  3.  0.  0
  libswscale      4.  1.100 /  4.  1.100
  libswresample   2.  1.100 /  2.  1.100
  libpostproc    54.  0.100 / 54.  0.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.41.100
  Duration: 00:00:45.08, start: 0.000000, bitrate: 1872 kb/s
    Stream #0:0(und): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p, 1920x1080, 1869 kb/s, 29.72 fps, 30 tbr, 16k tbn, 32k tbc (default)
    Metadata:
      handler_name    : VideoHandler
Input #1, png_pipe, from 'watermark.png':
  Duration: N/A, bitrate: N/A
    Stream #1:0: Video: png, rgba(pc), 64x64, 25 tbr, 25 tbn, 25 tbc
[Parsed_blend_0 @ 00750600] First input link top parameters (size 1920x1080, SAR 0:1) do not match the corresponding second input link bottom parameters (64x64, SAR 0:1)
[Parsed_blend_0 @ 00750600] Failed to configure output pad on Parsed_blend_0
Error configuring complex filters.
Invalid argument


    



    The result looks like some resolution issue with the parameters. So that I tried to scale the watermark before blending.

    



    ffmpeg -y -i input.mp4 -i watermark.png -filter_complex "[0:0]scale=1920x1080[a]; [1:0]scale=1920x1080[b]; [a][b]blend=all_mode=overlay:all_opacity=0.3" -c:v libx264 -an output.mp4


    



    FFMPEG works with these parameters. But the output wasn't I expected, because watermark had been stretched.
Any idea to blend watermark with different resolution without stretching to video with transparency ?

    



    Here are the testing file. (ffmpeg version 3.1.2)
https://drive.google.com/open?id=0B2X3VLS01TogdHVJZ2I1ZC1GUUU
https://drive.google.com/open?id=0B2X3VLS01TogbjhuZTlBOFFpN1k