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  • Selection of projects using MediaSPIP

    2 mai 2011, par

    The examples below are representative elements of MediaSPIP specific uses for specific projects.
    MediaSPIP farm @ Infini
    The non profit organizationInfini develops hospitality activities, internet access point, training, realizing innovative projects in the field of information and communication technologies and Communication, and hosting of websites. It plays a unique and prominent role in the Brest (France) area, at the national level, among the half-dozen such association. Its members (...)

  • Other interesting software

    13 avril 2011, par

    We don’t claim to be the only ones doing what we do ... and especially not to assert claims to be the best either ... What we do, we just try to do it well and getting better ...
    The following list represents softwares that tend to be more or less as MediaSPIP or that MediaSPIP tries more or less to do the same, whatever ...
    We don’t know them, we didn’t try them, but you can take a peek.
    Videopress
    Website : http://videopress.com/
    License : GNU/GPL v2
    Source code : (...)

  • 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 (...)

Sur d’autres sites (4086)

  • How to force "full range" flag on export

    28 janvier 2019, par Emanuele Vissani

    I have an ffmpeg command to remap audio tracks to descrete channels in a ProRes 4444 quicktime file. Even if the input video is copied to the output, the exported file is interpreted by a professional video player software as video range (16-234 values) instead of the original full range (0-255 values), making it look more contrasted.
    The content is actually correct, changing manually the range setting in the player software gives back the right light range, so I think the output file just lose some kind of range flag.

    I already tried the following options without results :

    -colorspace bt709 -movflags +write_colr

    -dst_range 1 -color_range 2

    -vf scale=out_range=full

    -vf scale=in_range=full:out_range=full

    Original command is :

    ffmpeg -i F:\_IMPORT\TST_ProRes4444_4k.mov -map 0:0 -c copy -map 0:1 -c copy -map_channel 0.2.0:0.2 -c:a pcm_s24le F:\_EXPORT\TEST\test.mov

    Thank you for your help.

  • VBV-CBR and ABR in X264

    11 décembre 2013, par xkfz007

    In x264 VBV-CBR RC mode is based on ABR and vbv-maxrate and vbv-bufsize are set. On the basis of frame QP decided by ABR, the MB row QP is decided by VBV-CBR for each row. I test these two modes and the command lines are listed :
    ABR : -o BasketballDrill_832x480_50_20131210102507.264 BasketballDrill_832x480_50.yuv 832x480 —fps 50 —frames 300 —bitrate 1120 —profile baseline —threads -1 -I 50 -v —psnr
    VBV-CBR : -o BasketballDrill_832x480_50_20131210102507_mb.264 BasketballDrill_832x480_50.yuv 832x480 —fps 50 —frames 300 —bitrate 1120 —vbv-maxrate 1120 —vbv-bufsize 1680 —profile baseline —threads 1 -I 50 -v —psnr

    The final results are :
    ABR : Y-PSNR 31.530dB, bitrate 1146.93kbps
    VBV-CBR : Y-PSNR 31.728dB, bitrate 1230.25kbps
    Compared to ABR, VBV-CBR achieved 4.9% bitrate promotion and 0.198dB PSNR promotion. But the PSNR promotion is lower than bitrate (1% bitrate=0.05dB).

    Having talked so much, I just want to ask what is the advantage of VBV-CBR compared ABR ? If ABR can get the reasonable results, why the VBV-cBR is needed ?
    In my opinion, VBV-CBR maybe can promote the subjective quality owing to deciding the QP for each MB row. But the bitrate also rises. Also I have compared some frames of the two modes, they are almost the same.
    Maybe there are some situations that are fit for VBV-CBR and I don't know. So guys, give me, the new to x264, some professional explanation.

  • FFmpeg : Cut from live stream RTSP

    10 septembre 2020, par Jax2171

    I cannot solve my problem and I have not found any solution.

    


    I capture an rtsp stream from an ip camera via the command :

    


    ffmpeg -stimeout 2000000 -abort_on empty_output -rtsp_transport tcp -i rtsp://admin:admin@192.168.1.15/av0_0 -c:v copy -c:a aac -f mpegts -y rec.ts


    


    The native video codec is h264 while the audio one is pcm. I capture the video stream without compression and compress the audio in aac to make it compatible with the ts container.

    


    I need to extract portions of video of X duration through during the capture. The command I use is :

    


    ffmpeg -ss X-i rec.ts -c:v copy -c:a copy -t Y -f mp4 -stimeout 60 -y cut.mp4


    


    Everything seems to work fine with no errors. However, the cut file has a slightly longer audio length than the video length. Sometimes the difference can be up to 1 second.

    


    My problem is that I have to chain all the cuts I make, and this difference in duration causes a very annoying lag between one video and another.

    


    It also happens that there is asynchronousness between audio and video in the cuts. The higher the -ss value, the more the audio anticipates the video.

    


    I state that I am not a professional but from what I have read it could be a problem of different PTS between audio and video, but I'm not sure. However, I am sure that the problem arises from the capture of the stream perhaps not in accordance with my needs.

    


    How can I solve ?

    


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