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  • Les vidéos

    21 avril 2011, par

    Comme les documents de type "audio", Mediaspip affiche dans la mesure du possible les vidéos grâce à la balise html5 .
    Un des inconvénients de cette balise est qu’elle n’est pas reconnue correctement par certains navigateurs (Internet Explorer pour ne pas le nommer) et que chaque navigateur ne gère en natif que certains formats de vidéos.
    Son avantage principal quant à lui est de bénéficier de la prise en charge native de vidéos dans les navigateur et donc de se passer de l’utilisation de Flash et (...)

  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Personnaliser en ajoutant son logo, sa bannière ou son image de fond

    5 septembre 2013, par

    Certains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;

Sur d’autres sites (6325)

  • iPhone camera shooting video using the AVCaptureSession and using ffmpeg CMSampleBufferRef a change in h.264 format is the issue. please advice

    4 janvier 2012, par isaiah

    My goal is h.264/AAC , mpeg2-ts streaming to server from iphone device.

    Current my source is FFmpeg+libx264 compile success. I Know gnu License. I want the demo program.

    I'm want to know that

    1.CMSampleBufferRef to AVPicture data is success ?

    avpicture_fill((AVPicture*)pFrame, rawPixelBase, PIX_FMT_RGB32, width, height);
     pFrame linesize and data is not null but pst -9233123123 . outpic also .
    Because of this I have to guess 'non-strictly-monotonic PTS' message

    2.This log is repeat.

    encoding frame (size= 0)
    encoding frame = "" , 'avcodec_encode_video' return 0 is success but always 0 .

    I don't know what to do...

    2011-06-01 15:15:14.199 AVCam[1993:7303] pFrame = avcodec_alloc_frame();
    2011-06-01 15:15:14.207 AVCam[1993:7303] avpicture_fill = 1228800
    Video encoding
    2011-0601 15:5:14.215 AVCam[1993:7303] codec = 5841844
    [libx264 @ 0x1441e00] using cpu capabilities: ARMv6 NEON
    [libx264 @ 0x1441e00] profile Constrained Baseline, level 2.0[libx264 @ 0x1441e00] non-strictly-monotonic PTS
    encoding frame (size=    0)
    encoding frame
    [libx264 @ 0x1441e00] final ratefactor: 26.74

    3.I have to guess 'non-strictly-monotonic PTS' message is the cause of all problems.
    what is this 'non-strictly-monotonic PTS' .

     this is source 

    (void)        captureOutput:(AVCaptureOutput *)captureOutput
           didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
                  fromConnection:(AVCaptureConnection *)connection
    {

       if( !CMSampleBufferDataIsReady(sampleBuffer) )
       {
           NSLog( @"sample buffer is not ready. Skipping sample" );
           return;
       }


       if( [isRecordingNow isEqualToString:@"YES"] )
       {
           lastSampleTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
           if( videoWriter.status != AVAssetWriterStatusWriting  )
           {
               [videoWriter startWriting];
               [videoWriter startSessionAtSourceTime:lastSampleTime];
           }

           if( captureOutput == videooutput )
           {
               [self newVideoSample:sampleBuffer];

               CVImageBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
               CVPixelBufferLockBaseAddress(pixelBuffer, 0);

               // access the data
               int width = CVPixelBufferGetWidth(pixelBuffer);
               int height = CVPixelBufferGetHeight(pixelBuffer);
               unsigned char *rawPixelBase = (unsigned char *)CVPixelBufferGetBaseAddress(pixelBuffer);

               AVFrame *pFrame;
               pFrame = avcodec_alloc_frame();
               pFrame->quality = 0;

               NSLog(@"pFrame = avcodec_alloc_frame(); ");

    //          int bytesPerRow = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);

    //          int bytesSize = height * bytesPerRow ;  

    //          unsigned char *pixel = (unsigned char*)malloc(bytesSize);

    //          unsigned char *rowBase = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);

    //          memcpy (pixel, rowBase, bytesSize);


               int avpicture_fillNum = avpicture_fill((AVPicture*)pFrame, rawPixelBase, PIX_FMT_RGB32, width, height);//PIX_FMT_RGB32//PIX_FMT_RGB8
               //NSLog(@"rawPixelBase = %i , rawPixelBase -s = %s",rawPixelBase, rawPixelBase);
               NSLog(@"avpicture_fill = %i",avpicture_fillNum);
               //NSLog(@"width = %i,height = %i",width, height);



               // Do something with the raw pixels here

               CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

               //avcodec_init();
               //avdevice_register_all();
               av_register_all();





               AVCodec *codec;
               AVCodecContext *c= NULL;
               int  out_size, size, outbuf_size;
               //FILE *f;
               uint8_t *outbuf;

               printf("Video encoding\n");

               /* find the mpeg video encoder */
               codec =avcodec_find_encoder(CODEC_ID_H264);//avcodec_find_encoder_by_name("libx264"); //avcodec_find_encoder(CODEC_ID_H264);//CODEC_ID_H264);
               NSLog(@"codec = %i",codec);
               if (!codec) {
                   fprintf(stderr, "codec not found\n");
                   exit(1);
               }

               c= avcodec_alloc_context();

               /* put sample parameters */
               c->bit_rate = 400000;
               c->bit_rate_tolerance = 10;
               c->me_method = 2;
               /* resolution must be a multiple of two */
               c->width = 352;//width;//352;
               c->height = 288;//height;//288;
               /* frames per second */
               c->time_base= (AVRational){1,25};
               c->gop_size = 10;//25; /* emit one intra frame every ten frames */
               //c->max_b_frames=1;
               c->pix_fmt = PIX_FMT_YUV420P;

               c ->me_range = 16;
               c ->max_qdiff = 4;
               c ->qmin = 10;
               c ->qmax = 51;
               c ->qcompress = 0.6f;

               /* 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;

               AVFrame* outpic = avcodec_alloc_frame();
               int nbytes = avpicture_get_size(PIX_FMT_YUV420P, c->width, c->height);

               //create buffer for the output image
               uint8_t* outbuffer = (uint8_t*)av_malloc(nbytes);

    #pragma mark -  

               fflush(stdout);

    <pre>//         int numBytes = avpicture_get_size(PIX_FMT_YUV420P, c->width, c->height);
    //          uint8_t *buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
    //          
    //          //UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"10%d", i]];
    //          CGImageRef newCgImage = [self imageFromSampleBuffer:sampleBuffer];//[image CGImage];
    //          
    //          CGDataProviderRef dataProvider = CGImageGetDataProvider(newCgImage);
    //          CFDataRef bitmapData = CGDataProviderCopyData(dataProvider);
    //          buffer = (uint8_t *)CFDataGetBytePtr(bitmapData);  
    //          
    //          avpicture_fill((AVPicture*)pFrame, buffer, PIX_FMT_RGB8, c->width, c->height);
               avpicture_fill((AVPicture*)outpic, outbuffer, PIX_FMT_YUV420P, c->width, c->height);

               struct SwsContext* fooContext = sws_getContext(c->width, c->height,
                                                              PIX_FMT_RGB8,
                                                              c->width, c->height,
                                                              PIX_FMT_YUV420P,
                                                              SWS_FAST_BILINEAR, NULL, NULL, NULL);

               //perform the conversion
               sws_scale(fooContext, pFrame->data, pFrame->linesize, 0, c->height, outpic->data, outpic->linesize);
               // Here is where I try to convert to YUV

               /* encode the image */

               out_size = avcodec_encode_video(c, outbuf, outbuf_size, outpic);
               printf("encoding frame (size=%5d)\n", out_size);
               printf("encoding frame %s\n", outbuf);


               //fwrite(outbuf, 1, out_size, f);

               //              free(buffer);
               //              buffer = NULL;      



               /* add sequence end code to have a real mpeg file */
    //          outbuf[0] = 0x00;
    //          outbuf[1] = 0x00;
    //          outbuf[2] = 0x01;
    //          outbuf[3] = 0xb7;
               //fwrite(outbuf, 1, 4, f);
               //fclose(f);
               free(outbuf);

               avcodec_close(c);
               av_free(c);
               av_free(pFrame);
               printf("\n");
    </pre>
  • HTML5 Audio() : Improved audio formats, mp3, mp4/aac + detection. Works on Palm Pre (tested on WebOS 1.4.1). HTML5 on for iPad, iPhone, Pre. Removed JS interval timer, using native timeupdate event. Callback frequency may be lower, but lower CPU. Element now unloaded + reference nulled at stop() / onfinish().

    17 mai 2010, par Scott Schiller

    m script/soundmanager2-jsmin.js m script/soundmanager2-nodebug-jsmin.js m script/soundmanager2.js HTML5 Audio() : Improved audio formats, mp3, mp4/aac + detection. Works on Palm Pre (tested on WebOS 1.4.1). HTML5 on for iPad, iPhone, Pre. Removed JS interval timer, using native timeupdate event. (...)

  • Google AppEngine flex as a transcoder [closed]

    6 septembre 2021, par jACK

    Situation :

    &#xA;

      &#xA;
    • A Nodejs/Express application running on appengine flex.
    • &#xA;

    • Using FFmpeg to cut videos, and merge different types of videos. 1080p 30fps videos, merged video duration usually around 8 hours.
    • &#xA;

    • Need for a massive amout of processing power for those edits.
    • &#xA;

    • The express server needs to be reachable 24/7 & flex is incredibly expensive if run on a 24/7 basis.
    • &#xA;

    &#xA;

    Goal :

    &#xA;

      &#xA;
    • To have a cost efficient ffmpeg transcoder on a private enviroment =>
    • &#xA;

    • Flex instance as a maximum spec, but as its idle reduce the price significantly.
    • &#xA;

    &#xA;

    Or is this a situation where a redesign is imminent ? eg. Compute Engine

    &#xA;

    Tried approach

    &#xA;

      &#xA;
    • B8 Standard instance => Since the payload is pretty big, its causing the B8 instance to crash.
    • &#xA;

    &#xA;

    Thanks.

    &#xA;