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  • Encodage et transformation en formats lisibles sur Internet

    10 avril 2011

    MediaSPIP transforme et ré-encode les documents mis en ligne afin de les rendre lisibles sur Internet et automatiquement utilisables sans intervention du créateur de contenu.
    Les vidéos sont automatiquement encodées dans les formats supportés par HTML5 : MP4, Ogv et WebM. La version "MP4" est également utilisée pour le lecteur flash de secours nécessaire aux anciens navigateurs.
    Les documents audios sont également ré-encodés dans les deux formats utilisables par HTML5 :MP3 et Ogg. La version "MP3" (...)

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

  • 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 (6411)

  • how to explain this C language code from ffmpeg remuxing

    20 avril 2017, par Fidona

    can someone help me what the meaning of this code ? this is a code from ffmpeg remuxing code.

    static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt, const char *tag, int hours, int mins, int secs, int us, int *time )
    
{
    
    AVRational *time_base = &fmt_ctx->streams[pkt->stream_index]->time_base;
    
    total = total + pkt->duration;
    
  //  printf( "%d:%d:%d.%d \n", hours,  mins,  secs, us );
    
    *time = av_q2d(*time_base) * pkt->pts ;
    
}

    I’m kind of new to C language. thank you !

  • How to get bit stream rate of a mpeg Transport Stream ?

    28 septembre 2015, par CompNet

    How can we get the bit rate of a transport stream from the TS source ? One way is to use a constant bitrate while multiplexing the encoded video into TS stream. But how does the variable bitstream work ?

    I found the command with ffmpeg like :

    ffmpeg -i encoded.mp4 -c copy -map 0 -vbsf h264_mp4toannexb mpegts out.ts

    but could not understand the meaning of -vbsf h264_mp4toannexb. Can anyone please explain me how does variable bitrate work ?

    Also, is there any other way we can find the timestamp of each TS packet multiplexed in the Transport Stream ?

  • how av_freep in ffmpeg works ?

    11 août 2016, par Billy Bob

    I have some questions regarding void pointer in C. I found out the following code, part of ffmpeg that I couldn’t understand... Could someone explain to me how it works ?

    void av_freep(void *arg)
    
{
    
        void *val;
    

    
        memcpy(&val, arg, sizeof(val));
    
        memcpy(arg, &(void *){ NULL }, sizeof(val));
    
        av_free(val);
    
}

    and later it’s called like this :

    char *str;
    
av_freep(&str);

    my questions :

    1. how passing address of str (&str) doesn’t trigger "incompatible type" warning when it’s compiled ? Shouldn’t &str type is become char** ?
    2. what’s the meaning of &(void *) NULL in one of memcpy parameter ?
    3. why it’s trying to free "val" which is not allocated ?

    Thanks !

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