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  • 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 (...)

  • 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 (...)

  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

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  • Codec not found while H.264 encoding using FFMPEG in iOS

    12 juin 2013, par Sukhpal Singh

    I am trying to encode video in h.264 format using FFMpeg in iOS. Actually I am receiving sample buffer from iPhone Camera and then converting it AVFrame and further from AVFrame to H.264 video. But while h.264 encoding if I use :

    codec = avcodec_find_encoder(CODEC_ID_MPEG1VIDEO);

    Then codec is found but if I use :

    codec = avcodec_find_encoder(CODEC_ID_H264);

    Then codec is nil means codec not found. Full code is as below :

    static void encode(AVFrame *picture)
    {
        AVCodec *codec;
        AVCodecContext *c= NULL;
        int i, out_size, size,  outbuf_size;
        uint8_t *outbuf, *picture_buf;

        printf("Video encoding\n");

        /* find the mpeg1 video encoder */

        //avcodec_init() ; // Also tried this but giving warning and not worked
        avcodec_register_all();

        codec = avcodec_find_encoder(CODEC_ID_H264);
        if (!codec) {
            fprintf(stderr, "codec not found\n");
            exit(1);
        }

        c= avcodec_alloc_context();
        picture= avcodec_alloc_frame();

        /* put sample parameters */
        c->bit_rate = 400000;
        /* resolution must be a multiple of two */
        c->width  = 352;
        c->height = 288;
        /* frames per second */
        c->time_base= (AVRational){1,25};
        c->gop_size = 10; /* emit one intra frame every ten frames */
        c->max_b_frames=1;
        c->pix_fmt = PIX_FMT_YUV420P;

        /* open it */
        if (avcodec_open(c, codec) < 0) {
            fprintf(stderr, "could not open codec\n");
            exit(1);
        }

            /* alloc image and output buffer */
        outbuf_size = 100000;
        outbuf = malloc(outbuf_size);
        size = c->width * c->height;
        picture_buf = malloc((size * 3) / 2); /* size for YUV 420 */

        out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture);

        NSLog(@"NSdada===%@",[NSData dataWithBytes:(const void *)outbuf length:out_size]);

        free(picture_buf);
        free(outbuf);

        avcodec_close(c);
        av_free(c);
        av_free(picture);
        printf("\n");
    }
  • Generating 64kbps audio-only mpegts for HTTP Live segmenter to meet 64kbps audio only requirement

    14 juin 2013, par Pobre

    I am trying to convert our mp4 files into mpeg-ts and segment it into .ts files for my iphone app to play. I am using Carson McDonalds's HTTP-Live-Video-Stream-Segmenter-and-Distributor to do that.

    I got his stuff complied and working correctly. I am currently trying to meet Apple's requirement where I need to provide a baseline 64 kbps audio only stream to my m3u8 playlist.
    Carson doesn't seem to have a profile for that.

    I need to be able to generate 64kbps audio-only stream from mp4, and turn that into mpeg-ts for the segmenter into ts. I am trying to find the right ffmpeg command that will validate without problem using Apple's mediastreamvalidator.

    So far I modified an existing encoding profile to try to achieve 64kbps total :

    ffmpeg -er 4 -i %s -f mpegts -acodec libmp3lame -ar 22050 -ab 32k -s 240x180 -vcodec libx264 -b 16k -flags +loop+mv4 -cmp 256 -partitions +parti4x4+partp8x8+partb8x8 -subq 7 -trellis 1 -refs 5 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -bt 64k -maxrate 16k -bufsize 16k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 4:3 -r 10 -g 30 -async 2 - | %s %s %s %s %s

    but then when I try to validate it using mediastreamvalidator, it gives error after few ts :

    Playlist Validation : OK

    Segments :

    sample_cell_4x3_64k-00001.ts :

    WARNING : Media segment exceeds target duration of 10.00 seconds by 1.30 seconds (segment duration is 11.30 seconds)

    sample_cell_4x3_64k-00002.ts :

    WARNING : Media segment exceeds target duration of 10.00 seconds by 1.40 seconds (segment duration is 11.40 seconds)

    ....
    ....

    sample_cell_4x3_64k-00006.ts :

    ERROR : (-1) Unknown video codec : 1836069494 (program 0, track 0)
    ERROR : (-1) failed to parse segment as either an MPEG-2 TS or an ES

    sample_cell_4x3_64k-00007.ts :

    ERROR : (-1) Unknown video codec : 1836069494 (program 0, track 0)
    ERROR : (-1) failed to parse segment as either an MPEG-2 TS or an ES

    ....
    ....
    Average segment duration : 10.26 seconds
    Average segment bitrate : 376797.92 bps
    Average segment structural overhead : 349242.17 bps (92.69 %)

    Is there someway I can generate this correctly with just audio which totals 64kbps and turn it into mpeg-ts ready to be segmented and validated correctly ?

    Am I approaching the problem right ?

  • Need help transcoding Red5 RTMP stream to MPEG2-TS

    5 février 2014, par reyniraron

    Me and my friend are going to make live shows and for that purpose I have set up a Red5 server on my old 2006 Intel Core Duo Mac mini running Mac OS X Snow Leopard Server 10.6.8.

    I use Flash Media Live Encoder to broadcast to Red5's oflaDemo application and the stream works great, except for the fact that I want the stream to work with iOS.
    I am developing an app for it, but I still need to convert my stream to Apple's HTTP Live Streaming protocol for it to work.
    Can anybody help me convert the RTMP stream to MPEG2-TS, because that's the format that mediastreamsegmenter supports ? I already have Apple's HTTP Live Streaming Tools installed on the server, so the segmenter's not a problem.

    FFmpeg doesn't work, at least not with the code I found here. With it a always get an "Operation not permitted" error. Xuggler doesn't work, not even with a Linux box.
    Can anybody please help me ? I'd really, really appreciate it.

    -Reynir Aron