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  • Les images

    15 mai 2013
  • Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur

    8 février 2011, par

    La visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
    Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
    Configuration de la boite multimédia
    Dès (...)

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

Sur d’autres sites (7448)

  • Segment duration variation is higher than the +/- 50% allowed by DASH-IF

    23 mars 2016, par timhysniu

    I am implement a proof of concept page with video player that uses DASH. I am having a difficult time getting the video right and I am not sure whether this is an encoding issue or MP4Box issue.

    Since I am working on Ubuntu I had to change a few parameters for ffmpeg, but according to what I read this should be fine :

    ~/ffmpeg/ffmpeg -c:a aac -ar 44100 -ac 1 -codec:v libx264 \
     -profile:v baseline -level 13 -b:v 2000k video_transcoded.mp4 -i video.mp4

    Then to create the MPD I am running this :

    MP4Box -dash 10000 -dash-profile live \
     -segment-name video_transcoded video_transcoded.mp4

    I am getting this response at the end, which might be why no player will play my video :

     [DASH] two languages in adaptation set: und will be kept eng will be ignored
     DASHing file video_transcoded.mp4
     [DASH]: Segment duration variation is higher than the  50% allowed by DASH-IF (min 1.044, max 10.448) - please reconsider encoding

    Here is the output of ffmpeg :

       ffmpeg version N-53477-g689211d-static http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2016 the FFmpeg developers
         built with gcc 5.3.1 (Debian 5.3.1-10) 20160224
         configuration: --enable-gpl --enable-version3 --disable-shared --disable-debug --enable-runtime-cpudetect --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --enable-libass --enable-gnutls --enable-libvidstab --enable-libsoxr --enable-frei0r --enable-libfribidi --disable-indev=sndio --disable-outdev=sndio --enable-librtmp --enable-libmfx --cc=gcc
         libavutil      55. 19.100 / 55. 19.100
         libavcodec     57. 28.100 / 57. 28.100
         libavformat    57. 28.100 / 57. 28.100
         libavdevice    57.  0.101 / 57.  0.101
         libavfilter     6. 39.102 /  6. 39.102
         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 'gladiator.mp4':
         Metadata:
           major_brand     : isom
           minor_version   : 1
           compatible_brands: isomavc1
           creation_time   : 2013-02-12 19:14:56
         Duration: 02:50:56.98, start: 0.000000, bitrate: 923 kb/s
           Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x544 [SAR 1:1 DAR 40:17], 823 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
           Metadata:
             creation_time   : 2013-02-12 19:14:56
             handler_name    : 2000.Extended.Remastered.720p.BluRay.x264-HDEVO.mkv.264#trackID=1:fps=23.976@GPAC0.5.1-DEV-rev4283
           Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 95 kb/s (default)
           Metadata:
             creation_time   : 2013-02-12 15:32:26
             handler_name    : Sound Media Handler
       [libx264 @ 0xaf12920] using SAR=1/1
       [libx264 @ 0xaf12920] frame MB size (80x34) > level limit (396)
       [libx264 @ 0xaf12920] DPB size (3 frames, 8160 mbs) > level limit (0 frames, 2376 mbs)
       [libx264 @ 0xaf12920] MB rate (65214) > level limit (11880)
       [libx264 @ 0xaf12920] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
       [libx264 @ 0xaf12920] profile Constrained Baseline, level 1.3
       [libx264 @ 0xaf12920] 264 - core 148 r236 a01e339 - H.264/MPEG-4 AVC codec - Copyleft 2003-2016 - http://www.videolan.org/x264.html - options: cabac=0 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=1 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=2000 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
       Output #0, mp4, to 'gladiator2.mp4':
         Metadata:
           major_brand     : isom
           minor_version   : 1
           compatible_brands: isomavc1
           encoder         : Lavf57.28.100
           Stream #0:0(und): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x544 [SAR 1:1 DAR 40:17], q=-1--1, 2000 kb/s, 23.98 fps, 24k tbn, 23.98 tbc (default)
           Metadata:
             creation_time   : 2013-02-12 19:14:56
             handler_name    : 2000.Extended.Remastered.720p.BluRay.x264-HDEVO.mkv.264#trackID=1:fps=23.976@GPAC0.5.1-DEV-rev4283
             encoder         : Lavc57.28.100 libx264
           Side data:
             cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 0 vbv_delay: -1
           Stream #0:1(eng): Audio: aac (LC) ([64][0][0][0] / 0x0040), 44100 Hz, mono, fltp, 69 kb/s (default)
           Metadata:
             creation_time   : 2013-02-12 15:32:26
             handler_name    : Sound Media Handler
             encoder         : Lavc57.28.100 aac
       Stream mapping:
         Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
         Stream #0:1 -> #0:1 (aac (native) -> aac (native))
       Press [q] to stop, [?] for help

    After transcoding is completed I get this :

    frame=  132 fps= 15 q=25.0 Lsize=    1112kB time=00:00:05.31 bitrate=1713.0kbits/s speed=0.603x    
    video:1062kB audio:45kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.414602%
    [libx264 @ 0xab63de0] frame I:1     Avg QP:21.29  size:121187
    [libx264 @ 0xab63de0] frame P:131   Avg QP:23.40  size:  7372
    [libx264 @ 0xab63de0] mb I  I16..4:  9.2%  0.0% 90.8%
    [libx264 @ 0xab63de0] mb P  I16..4:  0.9%  0.0%  0.3%  P16..4: 37.2%  7.0%  1.8%  0.0%  0.0%    skip:52.7%
    [libx264 @ 0xab63de0] final ratefactor: 21.58
    [libx264 @ 0xab63de0] coded y,uvDC,uvAC intra: 48.8% 72.2% 30.7% inter: 8.9% 14.6% 0.8%
    [libx264 @ 0xab63de0] i16 v,h,dc,p: 28% 33% 18% 21%
    [libx264 @ 0xab63de0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 22% 16% 15%  8%  7%  8%  6% 12%  6%
    [libx264 @ 0xab63de0] i8c dc,h,v,p: 52% 21% 19%  8%
    [libx264 @ 0xab63de0] ref P L0: 92.9%  5.2%  1.8%
    [libx264 @ 0xab63de0] kb/s:1646.80
    [aac @ 0xab64c40] Qavg: 112.650

    What can I do to make this work ?

  • Merge videos with different Frame Rates using MP4Parser

    30 juillet 2017, par BorisB

    I am currently successful at using MP4Parser library (https://github.com/sannies/mp4parser) to merge two videos created by my phones camera with same frame rates and resolutions. However when I try to merge one I encode via Android MediaCodec with the same resolution and same codec to the one recorded via the phones camera it produces an unplayable file with no errors.

    The only difference between the two files that I can see is the Camera file has frame rates of this :

    Frame rate mode : Variable
    Frame rate : 29.970 (29970/1000) FPS
    Minimum frame rate : 29.831 FPS
    Maximum frame rate : 30.030 FPS

    and the one I generate via Media Codec has this :

    Frame rate mode : Constant
    Frame rate : 30.000 FPS

    MP4 parser documentation says :
    ’It is important to emphasize that you cannot append any two tracks with : Different resolutions or Different frame-rates’

    So yeah I guess I’m out of luck with that solution.

    Now the only two others solutions I have come across are FFMPEG (which I don’t want to bother with because of licensing issues) and using Mediacodec to first decoded and then encode the video files together.

    Is using Mediacodec basically the most sound approach here ? Will there be problems when I need to add audio into the mix later on ? Most importantly does anyone have a good examples of doing this type of merge ?

    I know http://bigflake.com/mediacodec/ is the best source for these types of examples but I can’t really see anything there that does exactly this. Any help would be greatly appreciated.

  • FFmpeg converting two videos with dynamic frame rates - dup/drop frames

    18 décembre 2017, par Matho

    I have problems with converting two videos using ffmpeg. Those videos have dynamic frame rate. I’m using this ffmpeg command :

    ffmpeg -y -i /storage/emulated/0/Movies/RMR/RMR_camera_2017-10-04-20-42-56.mp4 -i /storage/emulated/0/Movies/RMR/RMR_screen_2017-10-04-20-42-56.mp4 -strict experimental -preset ultrafast -filter_complex [0]scale=iw/4:ih/4[pip];[pip]transpose=2[rotate];[1][rotate]overlay=main_w-overlay_w-30:main_h-overlay_h-10 -profile:v main -level 3.1 -ar 44100 -b:a 160k -crf 20 -s 720x1280 -vcodec h264 -vsync 2 -acodec aac -movflags +faststart /storage/emulated/0/Movies/RMR/out.mp4

    I’m using -vsync to drop duplicated frames. This is not good enough, video is with freezing frames. How can I prevent freezing ?