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  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • 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 (...)

  • Contribute to translation

    13 avril 2011

    You can help us to improve the language used in the software interface to make MediaSPIP more accessible and user-friendly. You can also translate the interface into any language that allows it to spread to new linguistic communities.
    To do this, we use the translation interface of SPIP where the all the language modules of MediaSPIP are available. Just subscribe to the mailing list and request further informantion on translation.
    MediaSPIP is currently available in French and English (...)

Sur d’autres sites (7173)

  • Crop individual frames of a video and then concat for output

    27 juin 2024, par Ashish Padave

    I want to Crop individual frames of a video and then concat for output. This works with 2 ffmpeg commands. The first one extracts each frame and the second concats them.
I want to get it done without the intermediate frames.

    


    Tried with the following

    


    ffmpeg  -y -i input.mp4 -filter_complex "[0:v]split=890[v0][v1][v2][v3][v4][v5];[v0]select='eq(n\,0)',setpts=PTS-STARTPTS,crop=404:720:225:0[v0]; [v1]select='eq(n\,1)',setpts=PTS-STARTPTS,crop=404:720:225:0[v1]; [v2]select='eq(n\,2)',setpts=PTS-STARTPTS,crop=404:720:225:0[v2]; [v3]select='eq(n\,3)',setpts=PTS-STARTPTS,crop=404:720:225:0[v3]; [v4]select='eq(n\,4)',setpts=PTS-STARTPTS,crop=404:720:225:0[v4]; [v5]select='eq(n\,5)',setpts=PTS-STARTPTS,crop=404:720:225:0[v5];[v0][v1][v2][v3][v4][v5]concat=n=6:v=1:a=0[outv]" -map "[outv]" -map 0:a? -c:a copy -vsync 2 output.mp4


    


    The above is an abridged version of the command. The video I am working with has 890 frames and a frame rate of 25.

    


    The output log with 890 frames is

    


    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf59.5.100
  Duration: 00:00:35.61, start: 0.000000, bitrate: 3380 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720, 3246 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 (h264) -> split
  concat -> Stream #0:0 (libx264)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[libx264 @ 0x55963ad4b700] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2 AVX512
[libx264 @ 0x55963ad4b700] profile High, level 3.0
[libx264 @ 0x55963ad4b700] 264 - core 155 r2917 0a84d98 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'output.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.29.100
    Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 404x720, q=-1--1, 25 fps, 12800 tbn, 25 tbc (default)
    Metadata:
      encoder         : Lavc58.54.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
frame=    3 fps=0.6 q=-1.0 Lsize=     586kB time=00:00:35.59 bitrate= 134.9kbits/s dup=0 drop=887 speed=6.73x
video:21kB audio:558kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.278277%
[libx264 @ 0x55963ad4b700] frame I:1     Avg QP:23.09  size: 17546
[libx264 @ 0x55963ad4b700] frame P:1     Avg QP:25.73  size:  2069
[libx264 @ 0x55963ad4b700] frame B:1     Avg QP:26.34  size:   845
[libx264 @ 0x55963ad4b700] consecutive B-frames: 33.3% 66.7%  0.0%  0.0%
[libx264 @ 0x55963ad4b700] mb I  I16..4:  8.4% 68.9% 22.7%
[libx264 @ 0x55963ad4b700] mb P  I16..4:  0.1%  0.6%  0.3%  P16..4: 28.5%  5.0%  3.9%  0.0%  0.0%    skip:61.6%
[libx264 @ 0x55963ad4b700] mb B  I16..4:  0.0%  0.1%  0.0%  B16..8: 29.6%  3.4%  0.3%  direct: 0.2%  skip:66.4%  L0:59.3% L1:35.6% BI: 5.1%
[libx264 @ 0x55963ad4b700] 8x8 transform intra:68.8% inter:73.3%
[libx264 @ 0x55963ad4b700] coded y,uvDC,uvAC intra: 73.0% 80.1% 36.4% inter: 3.9% 7.0% 0.7%
[libx264 @ 0x55963ad4b700] i16 v,h,dc,p:  2% 74%  6% 18%
[libx264 @ 0x55963ad4b700] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 13% 36% 20%  8%  4%  2%  6%  4%  8%
[libx264 @ 0x55963ad4b700] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 20% 41% 10%  4%  7%  4%  5%  3%  5%
[libx264 @ 0x55963ad4b700] i8c dc,h,v,p: 44% 37% 14%  6%
[libx264 @ 0x55963ad4b700] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x55963ad4b700] kb/s:1364.00


    


    So it is basically dropping 887 frames. The output file has the full audio but no video.
Is this even possible ?

    


  • Using ffprobe/ffmpeg to extract individual frames and types in playback sequence

    24 janvier 2018, par Hélder

    I am able to extract keyframes using ffmpeg. Something like this that I have been using :

    ffmpeg -i input.mp4 -vf "select='eq(pict_type\,I)" -vsync vfr -qscale:v 2 I-thumbnails-%02d.png -vf "select='eq(pict_type\,B)" -vsync vfr -qscale:v 2 B-thumbnails-%02d.png -vf "select='eq(pict_type\,P)" -vsync vfr -qscale:v 2 P-thumbnails-%02d.png

    Now the issue is, I would like these extracted frames to be in playback sequence, if possible, the way they are extracted should have a timestamp or any way to know that they start in a certain sequence, example, from start to end :

    IBBBIPPB......BI

    but in a way that I can sort the frames in the playback sequence.

    I want to use this to load in python to extract motion vectors but they should all follow certain playback sequence. Any help ?

  • Live streaming of processed frames to AWS

    22 avril 2021, par MinasCham

    I'm working on a project where i need to capture live video feed from an RTSP camera source, process the video frame-by-frame and stream the result to an AWS Service.

    


    So far, my solution :

    


      

    • Captures frames from the RTSP camera source using OpenCV and performs some processing.
    • 


    • Feeds the processed frames to an ffmpeg pipe that packages the content for online streaming (HTTP Live Streaming - hls) and saves it locally.
    • 


    • Transfers the media content to an Amazon Kinesis Video Stream using a Gstreamer pipeline element with kvssink as a sink element.
    • 


    


    My questions are :

    


      

    • Currently I'm saving the content both locally and on an Amazon Kinesis Video Stream. Is this efficient ?
    • 


    • Is it possible to directly stream the frames to the Amazon kinesis Video Stream (perhaps by connecting the ffmpeg output with the gstreamer pipeline element) ?
    • 


    • Is the file format suitable for this implementation or would it better to encode the media differently ?
    •