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  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

  • Support audio et vidéo HTML5

    10 avril 2011

    MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
    Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
    Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
    Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)

  • De l’upload à la vidéo finale [version standalone]

    31 janvier 2010, par

    Le chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
    Upload et récupération d’informations de la vidéo source
    Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
    Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)

Sur d’autres sites (5820)

  • Revision d115dbc24c : Adjust style to match Google Coding Style a little more closely. Most of these

    30 octobre 2012, par Ronald S. Bultje

    Changed Paths : Modify /vp8/common/onyx.h Modify /vp8/encoder/bitstream.c Modify /vp8/encoder/dct.c Modify /vp8/encoder/encodeframe.c Modify /vp8/encoder/encodeintra.c Modify /vp8/encoder/firstpass.c Modify /vp8/encoder/generic/csystemdependent.c (...)

  • FFMPEG silencedetect output does not match Audacity Sound Finder

    12 avril 2017, par tngo

    I’m currently working on labeling sound sections in an audio file.

    When I ran my audio file through Audacity Sound Finder with the following settings this is what I get

    0.448980    0.498866    1
    
0.698413    0.927891    2
    
1.147392    1.426757    3
    
1.566440    1.815873    4

    These are the first 4 labels for the audio file where the sounds were found to be louder than -12dB.

    However when I ran the same audio file through FFMPEG silencedetect filter with n=-12dB:d=0.1 this is the output

    [silencedetect @ 000000000272a8c0] silence_start: -0.00712018
    
[silencedetect @ 000000000272a8c0] silence_end: 0.371519 | silence_duration: 0.378639
    
[silencedetect @ 000000000272a8c0] silence_start: 0.457279
    
[silencedetect @ 000000000272a8c0] silence_end: 0.650159 | silence_duration: 0.19288
    
[silencedetect @ 000000000272a8c0] silence_start: 0.828798
    
[silencedetect @ 000000000272a8c0] silence_end: 1.11456 | silence_duration: 0.28576
    
[silencedetect @ 000000000272a8c0] silence_start: 1.38608
    
[silencedetect @ 000000000272a8c0] silence_end: 1.8576 | silence_duration: 0.1
    
[silencedetect @ 000000000272a8c0] silence_start: 2.31488

    For FFMPEG to detect sound I’m considering silence_end to be sound_start and silence_start to be sound_end. With that logic the output from FFMPEG actually is

    0.371519 0.457279 1
    
0.650159 0.828798 2
    
1.11456  1.38608  3
    
1.8576   2.31488  4

    To me it seems like all the timestamps from FFMPEG are shifted to the left compare to Audacity Sound Finder. Is there something that I’m missing ?

    Any help would be much appreciated.
    Thanks,

  • FPS from RTSP stream info does not match actual framerate

    17 mai 2021, par Krapow

    I have a 25FPS RTSP stream coming from an IP-camera. I can successfully display the video stream. But when analyzing the stream with ffmpeg (ffprobe actually), I observe fewer frames per second rate :

    


    $ ffprobe -rtsp_transport tcp -i rtsp://camera_ip:554/stream -select_streams v:0 -show_frames -show_entries frame=coded_picture_number,pkt_pts_time -of csv=p=0
Stream #0:0: Video: h264 (Main), yuvj420p(pc, bt709, progressive), 640x480, 25 fps, 25 tbr, 90k tbn, 50 tbc
0.400000,0
0.080000,1
0.120000,2
0.200000,3
0.240000,4
0.320000,5
0.360000,6
0.440000,7
0.480000,8
0.560000,9
0.600000,10
0.680000,11
0.720000,12
0.800000,13
0.840000,14
0.920000,15
0.960000,16
1.040000,17
1.080000,18
1.160000,19
1.200000,20
1.280000,21
1.320000,22
1.400000,23
1.440000,24
1.520000,25
1.560000,26
1.640000,27
1.680000,28
1.760000,29
1.800000,30
1.880000,31
1.920000,32
2.000000,33


    


    We can clearly see the 80ms gap between some of the frames, resulting in a 16fps stream.

    


    I have observed the same framerate issue with GStreamer (printing information in the rtpjitterbuffer indicates the frame gap is sometimes 80ms and sometimes 40ms). But the weird thing is, I encountered the same issue with an HDMI-RJ45 decoder, and I doubt the same issue comes from 2 different devices.
I didn't get much more informations using -loglevel debug or trace.
Does anybody have an idea about what is going wrong in the stream ?

    


    (I used ffprobe 4.2.3 and the last "2021-05-09-git-8649f5dca6-full_build-www.gyan.dev" with the same results, and GStreamer 1.16.2 with a pipeline like "urisourcebin ! h264depay ! h264parse ! fakesink")

    


    EDIT : The camera skipping of frames was caused by the activation of a third stream in the options. I find it really weird that it skips exactly the same frames every seconds. However, I still haven't found the cause of the downrate on my RTSP encoder.
Anyway, this was actually hardware related and not software related.

    


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