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  • L’espace de configuration de MediaSPIP

    29 novembre 2010, par

    L’espace de configuration de MediaSPIP est réservé aux administrateurs. Un lien de menu "administrer" est généralement affiché en haut de la page [1].
    Il permet de configurer finement votre site.
    La navigation de cet espace de configuration est divisé en trois parties : la configuration générale du site qui permet notamment de modifier : les informations principales concernant le site (...)

  • Support de tous types de médias

    10 avril 2011

    Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)

  • Keeping control of your media in your hands

    13 avril 2011, par

    The vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
    While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
    MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
    MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)

Sur d’autres sites (5736)

  • Is there anyway to tell if an openCV cap.read() call will fail before it begins to parse a video ?

    18 novembre 2022, par aris-t

    Problem : I am per frame parsing very long videos with a complex algorithm for AI applications in python. This is a slow and long process even using multiprocessing and threading tricks. Therefore it is very annoying when it dies half way through its process due to an open CV issue with the video.

    


    Request : Does anyone know a good way in python for open cv to raise an error before it begins to parse a video if the video would later throw a fatal error or None from cap.read() ? An added bonus would for the solution to at least give me a frame number and a reason so that I may edit or reconvert the video to fix this.

    


    Latest Issue :

    


    [h264 @ 0x41cad80] Invalid NAL unit size (-66445153 > 10189).
[h264 @ 0x41cad80] Error splitting the input into NAL units.


    


    Thanks in advance.

    


  • Merging\Joining three FFMPEG Commands (Drawtext / -filter_complex overlay / anullsrc=channel_layout)

    18 décembre 2020, par roar

    Currently I am using three different commands to create three mp4s only to delete the two "temporary" videos using this code.

    


    @ECHO OFF
ffmpeg -f lavfi -i color=size=1280x720:duration=5:rate=25:color=Black -vf "drawtext=fontfile='GothamRnd-Book.otf':line_spacing=15:fontsize=15:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text=Stack Exchange" "out1.mp4"
ffmpeg -i "out1.mp4" -i logo.png -filter_complex "overlay=x=10:y=10" "out2.mp4"
ffmpeg -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 -i "out2.mp4" -c:v copy -c:a aac -shortest "out3.mp4"
del "out1.mp4"
del "out2.mp4"
pause


    


    The nearest I have come is moving the anullsrc=channel_layout into the -filter_complex but that results in a long encode that I dont really understand what it is going because if I ctrl-c to cancel the batch still creates out3.mp4 correctly.

    


    ffmpeg -f lavfi -i color=size=1280x720:duration=5:rate=25:color=Black -vf "drawtext=fontfile='GothamRnd-Book.otf':line_spacing=15:fontsize=15:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text=Stack Exchange" "out1.mp4"
ffmpeg -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000  -i "out1.mp4" -i logo.png -filter_complex "overlay=x=10:y=10" "out3.mp4"


    


    It seems like this could be streamlined to not create the temporary files.
But maybe this is the only way to do this. Thank you for any assistance and sorry if the answer is obvious.

    


    Rory

    


  • ffmpeg : How does one designate what parts of an overlay video stream let the underlay video stream show through ?

    21 février 2023, par Walt Howard

    Stream 0 is a rotating planet created using povray. (https://www.povray.org/)

    


    Stream 1 is just a static jpeg of stars.

    


    I'm using overlay like this :

    


    nice ffmpeg -i protoplanet.mp4 -i stars.jpg \
         -filter_complex "[0:v]scale=1024:768[scaled];[1:v][scaled]overlay=0:0" \
         -movflags faststart -pix_fmt yuv420p -r 10 planet.mp4


    


    I had it working when I used the output from povray directly. I didn't have to know why that worked, because it just did. However, after adding some post processing to the planet video, the entire video has no alpha channel (educated guess) so the background stream (Stream 1) cannot show through.

    


    The post processing I did was this (which works great) : https://www.reddit.com/r/ffmpeg/comments/im2mkp/creating_a_retro_glow_effect_with_ffmpeg/

    


    But that made the video unable to have an overlay background possibly due to it destroying the alpha channel and turning many of the blacks to dark grey.

    


    I can merge the pure POVRAY output and the background and then add the glow effect, but it adds the effect to the background stars and captions also which ruins the effect to some degree. I want to glo-ify the planet first, then stick it on a pure starfield background.

    


    In thinking this over I may have to recreate the alpha channel after adding the glow effect, using a nearest match to black and dark grey to alpha.

    


    Hmmm. It might be a codec issue as I didn't specify any -c:v in any of my commands....

    


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