Recherche avancée

Médias (1)

Mot : - Tags -/biomaping

Autres articles (6)

  • 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)

  • lavc/ffv1 : Properly check that the 4th and 5th quant tables are zeroes

    5 janvier 2020, par Derek Buitenhuis
    lavc/ffv1 : Properly check that the 4th and 5th quant tables are zeroes

    Currently, the decoder checks the 128th value of the 4th quant table during
    
while deriving the context on each sample, in order to speed itself up. This
    
is due to relying on the behavior of FFmpeg's FFV1 encoder, in which if that
    
value is zero, the entire 4th and 5th quant tables are assumed to be entirely
    
zero.
    

    This does not match the FFV1 spec, which has no such restriction, and after
    
some discussion, it was decided to fix FFmpeg to abide by the spec, rather
    
than change the spec.
    

    We will now check whether the 4th and 5th quant tables are zero properly,
    
by checking the 128th valye of both tables (which means they are zero due
    
to the way they're coded in the bitstream).
    

    For further context, the FFV1 issue in question is located at :
    

        https://github.com/FFmpeg/FFV1/issues/169
    

    Signed-off-by : Derek Buitenhuis <derek.buitenhuis@gmail.com>
    • [DH] libavcodec/ffv1_template.c

  • Python FFmpeg : Setting VBR and BT.709

    14 décembre 2019, par Cryptonaut

    I’m using this Python library to programmatically generate a short video using an image (.png) as input. The video needs to match the specifications of another video created by someone else.

    The key differences between my output and the other are the following (these are the media attributes I desire to have) :

    How would I achieve VBR ? It was my understanding ProRes 422 HQ natively used unconstrained VBR yet my output specifies CBR.

    Secondly, as can be seen from my code, I’m attempting to conform to BT.709. However, my media information output does not specify this. What am I doing incorrectly ?

    Here’s my code :

        image = ffmpeg.input(input_image, t='00:00:10', framerate='24000/1001', loop='1', probesize='42M')
    

    
    output = ffmpeg.output(image, output_video,
    
    f='mov',
    
    vcodec='prores_ks',
    
    vprofile='3',
    
    pix_fmt='yuv422p10le',
    
    g='48',
    
    video_track_timescale='24000',
    
    movflags='use_metadata_tags',
    
    timecode='00:00:00:00',
    
    color_primaries='bt709',
    
    color_trc='bt709',
    
    colorspace='bt709',
    
    qcomp='1',
    
    # BT.709 issue solved by adding the bsf option as seen via the line below
    
    bsf='prores_metadata=color_primaries=bt709:color_trc=bt709:colorspace=bt709', 
    
    vf='scale=in_range=full:in_color_matrix=bt709:out_range=full:out_color_matrix=bt709')
    

    
    output.run()

    Here’s the media information produced by my output :

    {
    
   "media":{
    
      "@ref":"Redacted",
    
      "track":[
    
         {
    
            "@type":"General",
    
            "VideoCount":"1",
    
            "OtherCount":"1",
    
            "FileExtension":"mov",
    
            "Format":"MPEG-4",
    
            "Format_Profile":"QuickTime",
    
            "CodecID":"qt  ",
    
            "CodecID_Version":"0000.02",
    
            "CodecID_Compatible":"qt  ",
    
            "FileSize":"196366623",
    
            "Duration":"10.010",
    
            "OverallBitRate":"156936362",
    
            "FrameRate":"23.976",
    
            "FrameCount":"240",
    
            "StreamSize":"2463",
    
            "HeaderSize":"28",
    
            "DataSize":"196364172",
    
            "FooterSize":"2423",
    
            "IsStreamable":"No",
    
            "File_Created_Date":"UTC 2019-12-13 19:26:37.150",
    
            "File_Created_Date_Local":"2019-12-13 19:26:37.150",
    
            "File_Modified_Date":"UTC 2019-12-13 19:27:20.303",
    
            "File_Modified_Date_Local":"2019-12-13 19:27:20.303"
    
         },
    
         {
    
            "@type":"Video",
    
            "StreamOrder":"0",
    
            "ID":"1",
    
            "Format":"ProRes",
    
            "Format_Version":"0",
    
            "Format_Profile":"422 HQ",
    
            "CodecID":"apch",
    
            "Duration":"10.010",
    
            "BitRate_Mode":"CBR",
    
            "BitRate":"156934237",
    
            "Width":"1920",
    
            "Height":"1080",
    
            "Sampled_Width":"1920",
    
            "Sampled_Height":"1080",
    
            "PixelAspectRatio":"1.000",
    
            "DisplayAspectRatio":"1.778",
    
            "Rotation":"0.000",
    
            "FrameRate_Mode":"CFR",
    
            "FrameRate":"23.976",
    
            "FrameCount":"240",
    
            "ColorSpace":"YUV",
    
            "ChromaSubsampling":"4:2:2",
    
            "ScanType":"Progressive",
    
            "Delay":"0.000",
    
            "StreamSize":"196364160",
    
            "Encoded_Library":"Lavc",
    
            "colour_description_present":"Yes",
    
            "colour_description_present_Source":"Stream",
    
            "colour_primaries_Source":"Stream",
    
            "transfer_characteristics_Source":"Stream",
    
            "matrix_coefficients_Source":"Stream"
    
         },
    
         {
    
            "@type":"Other",
    
            "StreamOrder":"1",
    
            "ID":"2",
    
            "Type":"Time code",
    
            "Format":"QuickTime TC",
    
            "Duration":"10.010",
    
            "FrameRate":"23.976",
    
            "TimeCode_FirstFrame":"00:00:00:00",
    
            "TimeCode_Striped":"Yes",
    
            "Language":"en",
    
            "Default":"No"
    
         }
    
      ]
    
   }
    
}

    Here’s the media information spec I’m trying to match :

    {
    
   "media":{
    
      "@ref":"Redacted",
    
      "track":[
    
         {
    
            "@type":"General",
    
            "VideoCount":"1",
    
            "OtherCount":"1",
    
            "FileExtension":"mov",
    
            "Format":"MPEG-4",
    
            "Format_Profile":"QuickTime",
    
            "CodecID":"qt  ",
    
            "CodecID_Version":"2005.03",
    
            "CodecID_Compatible":"qt  ",
    
            "FileSize":"1397430682",
    
            "Duration":"70.737",
    
            "OverallBitRate_Mode":"VBR",
    
            "OverallBitRate":"158042403",
    
            "FrameRate":"23.976",
    
            "FrameCount":"1696",
    
            "StreamSize":"9898",
    
            "HeaderSize":"28",
    
            "DataSize":"1397420796",
    
            "FooterSize":"9858",
    
            "IsStreamable":"No",
    
            "Encoded_Date":"UTC 2019-04-29 22:26:32",
    
            "Tagged_Date":"UTC 2019-04-29 22:26:32",
    
            "File_Created_Date":"UTC 2019-12-12 16:52:57.215",
    
            "File_Created_Date_Local":"2019-12-12 16:52:57.215",
    
            "File_Modified_Date":"UTC 2019-12-12 17:25:58.903",
    
            "File_Modified_Date_Local":"2019-12-12 17:25:58.903",
    
            "Encoded_Application":"DVP Factory r561 (2019-04-25), Host: dvp07"
    
         },
    
         {
    
            "@type":"Video",
    
            "StreamOrder":"0",
    
            "ID":"1",
    
            "Format":"ProRes",
    
            "Format_Version":"0",
    
            "Format_Profile":"422 HQ",
    
            "CodecID":"apch",
    
            "Duration":"70.737",
    
            "Duration_LastFrame":"-0.000",
    
            "BitRate_Mode":"VBR",
    
            "BitRate":"158040381",
    
            "Width":"1920",
    
            "Height":"1080",
    
            "Sampled_Width":"1920",
    
            "Sampled_Height":"1080",
    
            "PixelAspectRatio":"1.000",
    
            "DisplayAspectRatio":"1.778",
    
            "Rotation":"0.000",
    
            "FrameRate_Mode":"CFR",
    
            "FrameRate":"23.976",
    
            "FrameCount":"1696",
    
            "ColorSpace":"YUV",
    
            "ChromaSubsampling":"4:2:2",
    
            "ScanType":"Progressive",
    
            "Delay":"0.000",
    
            "StreamSize":"1397420784",
    
            "Encoded_Library":"agi0",
    
            "Language":"en",
    
            "Encoded_Date":"UTC 2019-04-29 22:26:32",
    
            "Tagged_Date":"UTC 2019-04-29 22:26:32",
    
            "colour_description_present":"Yes",
    
            "colour_description_present_Source":"Container / Stream",
    
            "colour_primaries":"BT.709",
    
            "colour_primaries_Source":"Container",
    
            "colour_primaries_Original_Source":"Stream",
    
            "transfer_characteristics":"BT.709",
    
            "transfer_characteristics_Source":"Container",
    
            "transfer_characteristics_Original_Source":"Stream",
    
            "matrix_coefficients":"BT.709",
    
            "matrix_coefficients_Source":"Container / Stream"
    
         },
    
         {
    
            "@type":"Other",
    
            "StreamOrder":"1",
    
            "ID":"2",
    
            "Type":"Time code",
    
            "Format":"QuickTime TC",
    
            "Duration":"70.737",
    
            "FrameRate":"23.976",
    
            "TimeCode_FirstFrame":"00:00:00:00",
    
            "TimeCode_Striped":"Yes",
    
            "Language":"en",
    
            "extra":{
    
               "Encoded_Date":"UTC 2019-04-29 22:26:32",
    
               "Tagged_Date":"UTC 2019-04-29 22:26:32"
    
            }
    
         }
    
      ]
    
   }
    
}

  • How do I avoid out of memory when using ffmpeg-python ?

    26 janvier 2020, par Takada Shigeomi

    When executing the following code, process ends up running out of memory.
    How do I avoid out of memory ?

    import ffmpeg
    

    
path_to_file = 'my_video.mp4'
    

    
source = ffmpeg.input(path_to_file)
    

    
# Memory usage goes up without reproducibility during processing.
    
out, _ = (
    
    source.video # Video file of about 100MB for 20 minutes
    
    .output('pipe:', format='rawvideo', pix_fmt='rgb24')
    
    .run(capture_stdout=True)
    
)
    

    
# The following error message is displayed.
    
MemoryError
    
av_interleaved_write_frame(): Broken pipe
    
Error writing trailer of pipe:: Broken pipe
    
frame= 5722 fps=367 q=-0.0 Lsize=15448652kB time=00:03:10.73 bitrate=663519.9kbits/s speed=12.2x
    
video:15449400kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
    
Conversion failed!

    My computer spec :

    • OS : Ubuntu 18.04
    • CPU : Core i3-9100F
    • Memory : 16GB
    • SSD : 256GB
    • ffmpeg version : 4.2.2
    • ffmpeg-python version : 0.2.0
    • Python version : 3.7.3

Navigation