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Autres articles (37)

  • La file d’attente de SPIPmotion

    28 novembre 2010, par

    Une file d’attente stockée dans la base de donnée
    Lors de son installation, SPIPmotion crée une nouvelle table dans la base de donnée intitulée spip_spipmotion_attentes.
    Cette nouvelle table est constituée des champs suivants : id_spipmotion_attente, l’identifiant numérique unique de la tâche à traiter ; id_document, l’identifiant numérique du document original à encoder ; id_objet l’identifiant unique de l’objet auquel le document encodé devra être attaché automatiquement ; objet, le type d’objet auquel (...)

  • Contribute to documentation

    13 avril 2011

    Documentation is vital to the development of improved technical capabilities.
    MediaSPIP welcomes documentation by users as well as developers - including : critique of existing features and functions articles contributed by developers, administrators, content producers and editors screenshots to illustrate the above translations of existing documentation into other languages
    To contribute, register to the project users’ mailing (...)

  • 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) (...)

Sur d’autres sites (5420)

  • ffmepg concat videos is blocking in a frame

    5 septembre 2020, par عليلو احمد

    I am using this command to concatinate videos and audio in one single video :

    


    subprocess.run("ffmpeg -stream_loop -1 -f concat -i input.txt -i "+audioPath+" -map 0:v -map 1:a -c:v libx264 -crf 29 -preset slower -shortest -movflags +faststart output.mp4")


    


    And i'm facing a problem, the video sometimes stack in a frame, see Example

    


  • upload video stream and audio stream on iOS

    18 juillet 2015, par ronan

    Here’s the needs : People record their video via my App and upload stream to our website, you know, like a live show.

    When they are recording, the network goes bad, then record audio instead of video.
    And when audience watch, first comes the video, in a certain time comes the audio with a static picture.

    How am I supposed to do that ? Thanks.

  • Unusual results extracting VP9 pkt_size with ffprobe as compared to H.264

    26 novembre 2016, par Jeff S.

    I’m trying to graph the bitrate over time for H.264 and VP9 videos by extracting the frame size with ffprobe, but many of the VP9 videos are showing significantly lower bitrate and total size than both the file size would indicate and that ffprobe reports.

    Can someone point me in the right direction for finding the missing bytes ?

    For example :

    # The extracted values and the ffprobe values are very close for mp4
    
Video Codec: h264
    
Video Bitrate: 0.668869
    
Frame Bitrate: 0.665552571931
    
Video Size: 6381536.0
    
Frame Total Size: 6349891
    

    
# The extracted values and the ffprobe values are very different for some vp9 videos
    
Video Codec: vp9
    
Video Bitrate: 0.600966
    
Frame Bitrate: 0.375144984531
    
Video Size: 5730519.0
    
Frame Total Size: 3577195

    Below is what I’m using for validation. Note that the sample videos do not contain audio.

    import subprocess
    
import json
    

    
def export_video_info(video_id):
    
    proc = subprocess.Popen(['ffprobe',
    
        '-v', 'quiet', '-print_format', 
    
        'json', '-show_format',
    
        '-show_streams', '-show_frames',
    
        video_id
    
        ],
    
        stdout=subprocess.PIPE,
    
    )
    
    return proc.communicate()[0]
    

    
# Example video:  https://www.youtube.com/watch?v=g_OdgCrnzYo
    
# youtube-dl --id -f 135 https://www.youtube.com/watch?v=g_OdgCrnzYo
    
# youtube-dl --id -f 244 https://www.youtube.com/watch?v=g_OdgCrnzYo
    
video_list = ['g_OdgCrnzYo.mp4', 'g_OdgCrnzYo.webm']
    

    
'''
    
Format for every frame: 
    

    
    {
    
        "media_type": "video",
    
        "key_frame": 0,
    
        "pkt_pts": 84484,
    
        "pkt_pts_time": "84.484000",
    
        "pkt_dts": 84484,
    
        "pkt_dts_time": "84.484000",
    
        "best_effort_timestamp": 84484,
    
        "best_effort_timestamp_time": "84.484000",
    
        "pkt_duration": 33,
    
        "pkt_duration_time": "0.033000",
    
        "pkt_pos": "7103361",
    
        "pkt_size": "28",
    
        "width": 854,
    
        "height": 480,
    
        "pix_fmt": "yuv420p",
    
        "sample_aspect_ratio": "1:1",
    
        "pict_type": "P",
    
        "coded_picture_number": 0,
    
        "display_picture_number": 0,
    
        "interlaced_frame": 0,
    
        "top_field_first": 0,
    
        "repeat_pict": 0
    
    },
    
'''
    

    

    
# NOTE: videos do not include audio
    
for video in video_list:
    
    output = json.loads(export_video_info(video))
    
    ff_bitrate = float(output['format']['bit_rate']) / 10**6
    
    ff_duration = float(output['format']['duration'])
    
    ff_codec = output['streams'][0]['codec_name']
    
    ff_size = float(output['format']['size'])
    
    frame_size_sum = 0
    
    for val, items in enumerate(output['frames']):
    
        if output['frames'][val]['media_type'] == 'video': 
    
            frame_size_sum += int(output['frames'][val]['pkt_size'])
    

    
    frame_bitrate = frame_size_sum / ff_duration * 8 / 10**6
    
    print('Video Codec: {}\nVideo Bitrate: {}\nFrame Bitrate: {}\nVideo Size: {}\nFrame Total Size: {}\n\n'.format(ff_codec, ff_bitrate, frame_bitrate, ff_size, frame_size_sum))

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