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  • 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 (...)

  • 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

  • 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 (5698)

  • x264 num_units_in_tick can not be correctly set

    3 mai 2012, par MIKU_LINK_SUCCESS

    When I use x264 lib to encode yuv video stream,I can not set the sps parameter num_units_in_tick(i_num_units_in_tick in struct). I init the x264_param_t as :

        x264_param_t*                     m_x264Param;
    

    
    if( x264_param_default_preset( m_x264Param, "superfast", "zerolatency" ) < 0 )
    
    return -1;
    

    
   x264_param_apply_fastfirstpass( m_x264Param );
    

    
    /* Apply profile restrictions. */
    
    //baseline
    
    if( x264_param_apply_profile( m_x264Param, "baseline" ) < 0 )
    
      return -1;

    The i_rc_method is set to 1. I set the parameters which decide the num_units_in_tick,then call x264_encoder_open to get x264_t .

        m_x264Param->i_timebase_den = 90000;
    
    m_x264Param->i_timebase_num = 3000;
    
    m_x264Param->i_fps_num = 60;
    
    m_x264Param->i_fps_den = 2;

    But, num_units_in_tick is still 1, and time_scale is still 60. How can I set num_units_in_tick to 3000, so one frame occupies 3000 timestamp unit.

  • Parsing NAL units using FFMPEG

    6 novembre 2013, par 2ndlife

    I am new to MPEG-4 and taking baby steps to learn it. I am using FFMPEG as reference.

    1. I understand that all mpeg-4 are encoded into NAL units and wrt to FFMPEG av_read_frame() function returns one NAL unit, Am I right ? Is frame a NAL unit ? (though it can be a combination of multiple NALs)

    2. I also saw that h264_parser.c implements a function called h264_parse which is calling parse_nal_units() inside, If i need to get NAL units how can I use this parse_nal_units from my main function ?

    3. What is av_parse_Parse2() function do ? does it return decoded NAL units ?

    4. OR FFMPEG has -vbsf h264_mp4toannexb switch to dump raw NAL units, Can somebody help me understand how I can use the same from my main function ?

    Please help me out here...
    - ash5

  • H264 : decode series of nal units with ffmpeg

    1er août 2014, par jsim

    I tried to decode a series of nal units with ffmpeg (libavcodec) but I get a "no frame" error. I produced the nal units with the guideline at http://stackoverflow.com/questions/2940671/how-to-encode-series-of-images-into-h264-using-x264-api-c-c. I tried the following strategy for decoding :

    avcodec_init();  
    
avcodec_register_all();  
    
AVCodec* pCodec;  
    
pCodec=lpavcodec_find_decoder(CODEC_ID_H264);  
    
AVCodecContext* pCodecContext;  
    
pCodecContext=lpavcodec_alloc_context();  
    
avcodec_open(pCodecContext,pCodec);  
    
AVFrame *pFrame;  
    
pFrame=avcodec_alloc_frame();
    
//for every nal unit:    
    
    int frameFinished=0;  
    
    //nalData2 is nalData without the first 4 bytes
    
    avcodec_decode_video(pCodecContext,pFrame,&frameFinished,(uint8_t*) nalData2,nalLength);

    I passed all units I got to this code but frameFinished stays 0. I guess there must be something wrong with the pCodecContext setup. Can someone send me a working example ?

    Thank you

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