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  • 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 : (...)

  • Les formats acceptés

    28 janvier 2010, par

    Les commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
    ffmpeg -codecs ffmpeg -formats
    Les format videos acceptés en entrée
    Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
    Les formats vidéos de sortie possibles
    Dans un premier temps on (...)

  • Ajouter notes et légendes aux images

    7 février 2011, par

    Pour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
    Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
    Modification lors de l’ajout d’un média
    Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...)

Sur d’autres sites (10397)

  • Why frame->pts increases by 20, rather than by 1 ?

    19 mars 2013, par user1914692

    Following the exmaples of ffmpeg : decoding_encoding.c and filtering_video.c, I process one video file taken by iPhone. The video file : .mov, video dimensions ; 480x272, video Codec : H.264/AVC, 30 frames per second, bitrate : 605 kbps.

    I first extract each frame, which is YUV.
    I convert YUV to RGB24, and process the RGB24, then write the RGB24 to a .ppm file. It shows the .ppm file is correct.

    Then I plan to encode processed RGB24 frames to a video file.
    Since MPEG does not support RGB24 picture format, I used AV_CODEC_ID_HUFFYUV.
    But the output video file (showing 18.5 MB) does not play. Movie Player on Ubuntu claims an error : Could not determine type of stream.
    I also tried it on VCL. It simply does not work, without any error information.

    My second questions is :
    For each extracted fram from the input video file, I get its pts as follows according to filtering_video.c :

    frame->pts = av_frame_get_best_effort_timestamp(frame);

    I print out each frame's pts, and find that it increases by 20, like below :

    pFrameRGB_count: 0,  frame->pts: 0
    
pFrameRGB_count: 1,  frame->pts: 20
    
pFrameRGB_count: 2,  frame->pts: 40
    
pFrameRGB_count: 3,  frame->pts: 60

    Where frame is the extracted frame from the input video, and pFrameRGB_count is the count for processed frame in RGB24 form.

    Why are they wrong ?

  • ffmpeg Live Input MP4 Error [migrated]

    3 mars 2013, par Brianjs

    Currently I have a mic and a webcam connected to my computer. I am running ffmpeg on CentOS 6.3.

    When I try to record a video without audio by :

    ffmpeg -y -f video4linux2 -t 15 -s 640x480 -r 25 -i /dev/video0 /home/irdb/Desktop/out2.mp4

    it runs perfectly and I get a nice video. However when I try to run with audio included by :

    ffmpeg -y -f video4linux2 -t 15 -s 640x480 -r 25 -i /dev/video0 -f alsa -ar 22050 -ab 64k -ac 2 -i default /home/irdb/Desktop/out2.mp4

    It errors out and prints :

    [NULL @ 0x1e33fc0] Codec is experimental but experimental codecs are not enabled,      see -strict -2
    
Output #0, mp4, to '/home/irdb/Desktop/out2.mp4':
    
Stream #0:0: Video: h264, yuv420p, 640x480, q=-1--1, 90k tbn, 25 tbc
    
Stream #0:1: Audio: none, 22050 Hz, 2 channels, flt, 128 kb/s
    
Stream mapping:
    
Stream #0:0 -> #0:0 (rawvideo -> libx264)
    
Stream #1:0 -> #0:1 (pcm_s16le -> aac)
    
Error while opening encoder for output stream #0:1 - maybe incorrect parameters such    as bit_rate, rate, width or height

    I assume this has to do with the first error as when I use something like mpg it works just fine. However I plan on streaming this live and want mp4 format as that is pretty much supported by all browsers (Firefox with flash fallback).

    Does anyone know how to get the audio to work without additional processing (as I want to stream live and not write to a file eventually).

  • Revision 32d88c2209 : Properly set size based on actual buffer layout VP9FrameSizeTestsLarge.OneByOne

    30 décembre 2014, par Yaowu Xu

    Changed Paths :
     Modify /test/encode_test_driver.cc


     Modify /test/video_source.h



    Properly set size based on actual buffer layout

    VP9FrameSizeTestsLarge.OneByOneVideo has been causing a failure in
    jenkins libvpx__unit_tests-valgrind_long for "using of uninitialized
    memory", the root cause was that the input image for this test was
    not initialized with proper size, therefore plan U and V were not
    initialized at all.

    This commit fixes the size initialization, and resolves the issue.

    Change-Id : Ic4dd1542b7bb0cb260a1e0aeeb505db21ae5edc8

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