Recherche avancée

Médias (3)

Mot : - Tags -/collection

Autres articles (106)

  • MediaSPIP 0.1 Beta version

    25 avril 2011, par

    MediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
    If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)

  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Creating farms of unique websites

    13 avril 2011, par

    MediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
    This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)

Sur d’autres sites (13726)

  • FFmpeg concatenation changes the duration and playback speed of the input videos

    24 février 2017, par Barnaby

    I have two input videos that I am concatenating using the FFmpeg concat demuxer :

    ffmpeg -f concat safe '0' -i /path/to/file.txt -c copy /path/to/output.mp4

    The file.txt contains the two file paths as follows :

    ffconcat version 1.0

    file /path/to/input/file1.mp4

    file /path/to/input/file2.mp4

    Unfortunately, the concatenated video has two issues :

    • The duration of the first input video is 4 seconds. In the output video, the last frame freezes for several seconds before the second input video starts.
    • The playback speed of the second input video is slowed down so that instead of being 7 seconds long, the video plays for around 14 or 15 seconds.

    I have tried specifying the duration of each video in the .txt file, as specified by the FFmpeg docs, but this doesn’t seem to make a difference to the output.

    I’m a bit of a newbie to FFmpeg, so any help is greatly appreciated !

    Edit - The properties of each input video as given by FFprobe :

    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'tmp/video/16382802.mp4':
     Metadata:
       major_brand     : isom
       minor_version   : 512
       compatible_brands: isomiso2avc1mp41
       encoder         : Lavf57.25.100
     Duration: 00:00:04.43, start: 0.000000, bitrate: 644 kb/s
       Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 360x640, 640 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
       Metadata:
         handler_name    : VideoHandler


    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'tmp/video/16382805.mp4':
     Metadata:
       major_brand     : isom
       minor_version   : 512
       compatible_brands: isomiso2avc1mp41
       encoder         : Lavf57.25.100
     Duration: 00:00:07.31, start: 0.023220, bitrate: 836 kb/s
       Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 360x640, 669 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
       Metadata:
         handler_name    : VideoHandler
       Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, 5.1, fltp, 158 kb/s (default)
       Metadata:
         handler_name    : SoundHandler

    Edit 2 - Stack trace when rewrapping the video (audio is lost) :

    ffmpeg version 3.0.1 Copyright (c) 2000-2016 the FFmpeg developers
     built with Apple LLVM version 7.3.0 (clang-703.0.31)
     configuration: --prefix=/usr/local/Cellar/ffmpeg/3.0.1 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-opencl --enable-libx264 --enable-libmp3lame --enable-libxvid --enable-libfreetype --enable-ffplay --enable-libfdk-aac --enable-frei0r --enable-nonfree --enable-vda
     libavutil      55. 17.103 / 55. 17.103
     libavcodec     57. 24.102 / 57. 24.102
     libavformat    57. 25.100 / 57. 25.100
     libavdevice    57.  0.101 / 57.  0.101
     libavfilter     6. 31.100 /  6. 31.100
     libavresample   3.  0.  0 /  3.  0.  0
     libswscale      4.  0.100 /  4.  0.100
     libswresample   2.  0.101 /  2.  0.101
     libpostproc    54.  0.100 / 54.  0.100
    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'https://s3-eu-west-1.amazonaws.com/stories.snaplytics.io/fTYbaN78DBVEQI0js0ydhNw/d3ef9a13-454c-4015-8412-cbd890e70e24.mp4':
     Metadata:
       major_brand     : isom
       minor_version   : 512
       compatible_brands: isomiso2avc1mp41
       encoder         : Lavf57.25.100
     Duration: 00:00:07.31, start: 0.023220, bitrate: 746 kb/s
       Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 360x640, 669 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
       Metadata:
         handler_name    : VideoHandler
       Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 67 kb/s (default)
       Metadata:
         handler_name    : SoundHandler
    Input #1, lavfi, from 'anullsrc':
     Duration: N/A, start: 0.000000, bitrate: 705 kb/s
       Stream #1:0: Audio: pcm_u8, 44100 Hz, stereo, u8, 705 kb/s
    Output #0, mp4, to '/Users/barnabytaylor/Documents/fanbytes-dashboard/tmp/video/16382805.mp4':
     Metadata:
       major_brand     : isom
       minor_version   : 512
       compatible_brands: isomiso2avc1mp41
       encoder         : Lavf57.25.100
       Stream #0:0(und): Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 360x640, q=2-31, 669 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 30k tbc (default)
       Metadata:
         handler_name    : VideoHandler
       Stream #0:1: Audio: aac (LC) ([64][0][0][0] / 0x0040), 44100 Hz, 5.1, fltp, 341 kb/s
       Metadata:
         encoder         : Lavc57.24.102 aac
    Stream mapping:
     Stream #0:0 -> #0:0 (copy)
     Stream #1:0 -> #0:1 (pcm_u8 (native) -> aac (native))
    Press [q] to stop, [?] for help
    frame=  219 fps= 57 q=-1.0 Lsize=   98706kB time=00:00:07.31 bitrate=110550.2kbits/s speed=1.91x    
    video:598kB audio:6kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 16257.420898%
    [aac @ 0x7ffbe2806e00] Qavg: 65536.000
  • How to set audio speed to 0.3 in Ffmpeg ?

    15 septembre 2020, par WebDiva

    I am using ffmpeg to set the audio and video speed to 0.3x. I can set the video speed but can't set the audio speed to 0.3x. Here is the command

    


    ffmpeg -y -i video.mp4 -vf "setpts=PTS/0.3" -r 50 -c:v mpeg4 -b:v 1500k -af "atempo=0.3" output.mp4


    


    It says :

    


    Value 0.300000 for parameter 'tempo' out of range [0.5 - 100]


    


    Is there a workaround ? Any help will be appreciated. Regards.

    


  • How can I speed up this side by side video stitch in FFMPEG

    21 octobre 2020, par ianf

    I have two videos the same size and pixel format (about 240x360) left and right that I want to stitch together.

    


    I'm using :

    


    ffmpeg -i left.mp4 -i right.mp4  -filter_complex "[0:v][1:v]hstack=inputs=2:shortest=1[v]; [0:a][1:a]amerge[a]" -map "[v]" -map "[a]" -ac 2 -shortest -y output.mp4


    


    which takes about 15 seconds on a 3 core machine. I see x1.25 on the conversion line.

    


    I know this isnt too bad, but any speed up I can make is going to help a lot as its in heavy use.

    


    Any ideas how I can improve this ?