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• VeriSilicon and WebM Support

  24 janvier 2011, par noreply@blogger.com (John Luther)

  Guest blogger Tomi Jalonen is Director of Product Marketing for Hantro video IP at VeriSilicon

  2011 is shaping up to be an exciting year at VeriSilicon Holdings in terms of WebM support. With the new year upon us, I want to share some updates about the work we are doing at VeriSilicon to move the WebM platform forward.

  VeriSilicon has been a longtime partner of On2/Hantro (Hantro is the video IP brand that Google acquired with On2 Technologies) and we were among the first hardware partners to commit to WebM video when the codec was open-sourced last year. After promoting WebM to the semiconductor industry during 2010, we’re excited that at CES 2011 the first tablet supporting WebM with full 1080p resolution was demonstrated. VeriSilicon licensed the WebM IP to this tablet manufacturer and provided engineering support to bring the technology to the showroom floor.

  In addition to licensing IPs, this year we’ll be taking the WebM experience a step further by taping out several application processor chips—including the WebM video IP for Android phones, xPad, and Google TV—to accelerate the deployment of WebM and HTML5 video playback into the market.

  The entire VeriSilicon team is very excited about the future of WebM. We believe that the availability of high-quality, optimized WebM hardware video IP, combined with other VeriSilicon audio and multimedia IP, will be a key ingredient for semiconductor companies to create competitive consumer products. After the launch of WebM, the interest in hardware-accelerated WebM video has been immense and we will continue working with the WebM Project to enable WebM and VP8 in many more chips in 2011.

  

• avformat/matroskadec : Check min_luminance more thoroughly

  16 février 2021, par Andreas Rheinhardt

  avformat/matroskadec : Check min_luminance more thoroughly
  In the absence of an explicitly coded minimal luminance, the current
  
  code inferred it to be -1, an invalid value. Yet it did not check the
  
  value lateron at all, so that if a valid maximum luminance is
  
  encountered, but no minimal luminance, an invalid minimal luminance of
  
   1 is exported. If an minimal luminance element with a negative value is
  
  present, it is exported, too. This can be simply fixed by adding a check
  
  for the value of the element.
  Yet given that a minimal luminance of zero Cd/m² is legal and can be
  
  coded with a length of zero, we must not use a fake default value to
  
  find out whether the element is present or not. Therefore this patch
  
  uses an explicit counter for it.
  While just at it, also check for max_luminance > min_luminance.
  Reviewed-by : Ridley Combs <rcombs@rcombs.me>
  
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/matroskadec.c

• Converting uint8_t data to AVFrame with FFmpeg

  30 octobre 2017, par J.Lefebvre

  I am currently working in C++ with the Autodesk 3DStudio Max 2014 SDK (toolset 100) and the Ffmpeg library in Visual Studio 2015 and trying to convert a DIB (Device Independent Bitmap) to uint8_t pointer array and then convert these data to an AVFrame.

  I don’t have any errors, but my video is still black and without meta data.
  (no time display, etc)

  I made approximatively the same with a Visual Studio Console application to convert jpeg image sequence from disk and this is working fine.
  (The only difference is that instead of converting jpeg to AVFrame with the Ffmpeg library, I try to convert raw data to an AVFrame.)

  So I think the problem could be either on the DIB conversion to the uint8_t data or the uint8_t data to the AVFrame.
  (The second is more plausible, because I used the SFML library to display a window with my rgb uint8_t* data for debuging and it is working fine.)

  I first initialize the ffmpeg library :

  This function is called once at the beginning.

  int Converter::Initialize(AVCodecID codec_id, int width, int height, int fps, const char *filename)
  
  {
  
      avcodec_register_all();
  
      av_register_all();
  
  
  
      AVCodec *codec;
  
      inputFrame = NULL;
  
      codecContext = NULL;
  
      pkt = NULL;
  
      file = NULL;
  
      outputFilename = new char[strlen(filename)]();
  
      *outputFilename = '\0';
  
      strcpy(outputFilename, filename);
  
  
  
      int ret;
  
  
  
      //Initializing AVCodecContext and getting PixelFormat supported by encoder
  
      codec = avcodec_find_encoder(codec_id);
  
      if (!codec)
  
          return 1;
  
  
  
      AVPixelFormat pixFormat = codec->pix_fmts[0];
  
      codecContext = avcodec_alloc_context3(codec);
  
      if (!codecContext)
  
          return 1;
  
  
  
      codecContext->bit_rate = 400000;
  
      codecContext->width = width;
  
      codecContext->height = height;
  
      codecContext->time_base.num = 1;
  
      codecContext->time_base.den = fps;
  
      codecContext->gop_size = 10;
  
      codecContext->max_b_frames = 1;
  
      codecContext->pix_fmt = pixFormat;
  
  
  
      if (codec_id == AV_CODEC_ID_H264)
  
          av_opt_set(codecContext->priv_data, "preset", "slow", 0);
  
  
  
      //Actually opening the encoder
  
      if (avcodec_open2(codecContext, codec, NULL) < 0)
  
          return 1;
  
  
  
      file = fopen(outputFilename, "wb");
  
      if (!file)
  
          return 1;
  
  
  
      inputFrame = av_frame_alloc();
  
      inputFrame->format = codecContext->pix_fmt;
  
      inputFrame->width = codecContext->width;
  
      inputFrame->height = codecContext->height;
  
  
  
      ret = av_image_alloc(inputFrame->data, inputFrame->linesize, codecContext->width, codecContext->height, codecContext->pix_fmt, 32);
  
  
  
      if (ret < 0)
  
          return 1;
  
  
  
      return 0;
  
  }

  Then for each frame, I get the DIB and convert to a uint8_t* it with this function :

  uint8_t* Util::ToUint8_t(RGBQUAD *data, int width, int height)
  
  {
  
      uint8_t* buf = (uint8_t*)data;
  
  
  
      int imageSize = width * height;
  
      size_t rgbquad_size = sizeof(RGBQUAD);
  
      size_t total_bytes = imageSize * rgbquad_size;
  
      uint8_t * pCopyBuffer = new uint8_t[total_bytes];
  
  
  
      for (int x = 0; x < width; x++)
  
      {
  
          for (int y = 0; y < height; y++)
  
          {
  
              int index = (x + width * y) * rgbquad_size;
  
              int invertIndex = (x + width* (height - y - 1)) * rgbquad_size;
  
  
  
              //BGRA to RGBA
  
              pCopyBuffer[index] = buf[invertIndex + 2];
  
              pCopyBuffer[index + 1] = buf[invertIndex + 1];
  
              pCopyBuffer[index + 2] = buf[invertIndex];
  
              pCopyBuffer[index + 3] = 0xFF;
  
          }
  
      }
  
  
  
      return pCopyBuffer;
  
  }
  
  
  
  void GetDIBBuffer(Interface* ip, BITMAPINFO *bmi, uint8_t** outBuffer)
  
  {
  
      int size;
  
  
  
      ViewExp& view = ip->GetActiveViewExp();
  
  
  
      view.getGW()->getDIB(NULL, &size);
  
  
  
      bmi = (BITMAPINFO *)malloc(size);
  
      BITMAPINFOHEADER *bmih = (BITMAPINFOHEADER *)bmi;
  
      view.getGW()->getDIB(bmi, &size);
  
  
  
      uint8_t * pCopyBuffer = Util::ToUint8_t(bmi->bmiColors, bmih->biWidth, bmih->biHeight);
  
  
  
      *outBuffer = pCopyBuffer;
  
  }

  This function is used to get the DIB :

  void GetViewportDIB(Interface* ip, BITMAPINFO *bmi, BITMAPINFOHEADER *bmih, BitmapInfo biFile, Bitmap *map)
  
  {
  
      int size;
  
  
  
      if (!biFile.Name()[0])
  
          return;
  
  
  
      ViewExp& view = ip->GetActiveViewExp();
  
  
  
      view.getGW()->getDIB(NULL, &size);
  
  
  
      bmi = (BITMAPINFO *)malloc(size);
  
      bmih = (BITMAPINFOHEADER *)bmi;
  
  
  
      view.getGW()->getDIB(bmi, &size);
  
  
  
      biFile.SetWidth((WORD)bmih->biWidth);
  
      biFile.SetHeight((WORD)bmih->biHeight);
  
      biFile.SetType(BMM_TRUE_32);
  
  
  
      map = TheManager->Create(&biFile);
  
      map->OpenOutput(&biFile);
  
      map->FromDib(bmi);
  
      map->Write(&biFile);
  
      map->Close(&biFile);
  
  }

  And after the conversion to AVFrame and video encoding :

  The EncodeFromMem function is call each frame.

  int Converter::EncodeFromMem(const char *outputDir, int frameNumber, uint8_t* data)
  
  {
  
      int ret;
  
  
  
      inputFrame->pts = frameNumber;
  
      EncodeFrame(data, codecContext, inputFrame, &pkt, file);
  
  
  
      return 0;
  
  }
  
  
  
  static void RgbToYuv(uint8_t *rgb, AVCodecContext *c, AVFrame *frame)
  
  {
  
      struct SwsContext *swsCtx = NULL;
  
      const int in_linesize[1] = { 3 * c->width };// RGB stride
  
      swsCtx = sws_getCachedContext(swsCtx, c->width, c->height, AV_PIX_FMT_RGB24, c->width, c->height, AV_PIX_FMT_YUV420P, 0, 0, 0, 0);
  
      sws_scale(swsCtx, (const uint8_t * const *)&rgb, in_linesize, 0, c->height, frame->data, frame->linesize);
  
  }
  
  
  
  static void EncodeFrame(uint8_t *rgb, AVCodecContext *c, AVFrame *frame, AVPacket **pkt, FILE *file)
  
  {
  
      int ret, got_output;
  
  
  
      RgbToYuv(rgb, c, frame);
  
  
  
      *pkt = av_packet_alloc();
  
      av_init_packet(*pkt);
  
      (*pkt)->data = NULL;
  
      (*pkt)->size = 0;
  
  
  
      ret = avcodec_encode_video2(c, *pkt, frame, &got_output);
  
      if (ret < 0)
  
      {
  
          fprintf(stderr, "Error encoding frame/n");
  
          exit(1);
  
      }
  
      if (got_output)
  
      {
  
          fwrite((*pkt)->data, 1, (*pkt)->size, file);
  
          av_packet_unref(*pkt);
  
      }
  
  }

  To finish I have a function that write the packets and free the memory :
  This function is called once at the end of the time range.

  int Converter::Finalize()
  
  {
  
      int ret, got_output;
  
      uint8_t endcode[] = { 0, 0, 1, 0xb7 };
  
  
  
      /* get the delayed frames */
  
      do
  
      {
  
          fflush(stdout);
  
          ret = avcodec_encode_video2(codecContext, pkt, NULL, &got_output);
  
          if (ret < 0)
  
          {
  
              fprintf(stderr, "Error encoding frame/n");
  
              return 1;
  
          }
  
          if (got_output)
  
          {
  
              fwrite(pkt->data, 1, pkt->size, file);
  
              av_packet_unref(pkt);
  
          }
  
      } while (got_output);
  
  
  
      fwrite(endcode, 1, sizeof(endcode), file);
  
      fclose(file);
  
  
  
      avcodec_close(codecContext);
  
      av_free(codecContext);
  
  
  
      av_frame_unref(inputFrame);
  
      av_frame_free(&inputFrame);
  
      //av_freep(&inputFrame->data[0]); //Crash
  
  
  
      delete outputFilename;
  
      outputFilename = 0;
  
  
  
      return 0;
  
  }

  EDIT :

  I modify my RgbToYuv function and create another one to convert back the yuv frame to an rgb one.

  This not really solve the problem, but maybe focus the problem on the conversion from YuvToRgb.

  This is the result of the conversion from YUV to RGB :

   ![YuvToRgb result] : https://img42.com/kHqpt+

  static void YuvToRgb(AVCodecContext *c, AVFrame *frame)
  
  {
  
      struct SwsContext *img_convert_ctx = sws_getContext(c->width, c->height, AV_PIX_FMT_YUV420P, c->width, c->height, AV_PIX_FMT_RGB24, SWS_BICUBIC, NULL, NULL, NULL);
  
      AVFrame * rgbPictInfo = av_frame_alloc();
  
      avpicture_fill((AVPicture*)rgbPictInfo, *(frame)->data, AV_PIX_FMT_RGB24, c->width, c->height);
  
      sws_scale(img_convert_ctx, frame->data, frame->linesize, 0, c->height, rgbPictInfo->data, rgbPictInfo->linesize);
  
  
  
      Util::DebugWindow(c->width, c->height, rgbPictInfo->data[0]);
  
  }
  
  static void RgbToYuv(uint8_t *rgb, AVCodecContext *c, AVFrame *frame)
  
  {
  
      AVFrame * rgbPictInfo = av_frame_alloc();
  
      avpicture_fill((AVPicture*)rgbPictInfo, rgb, AV_PIX_FMT_RGBA, c->width, c->height);
  
  
  
      struct SwsContext *swsCtx = sws_getContext(c->width, c->height, AV_PIX_FMT_RGBA, c->width, c->height, AV_PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);
  
      avpicture_fill((AVPicture*)frame, rgb, AV_PIX_FMT_YUV420P, c->width, c->height);    
  
      sws_scale(swsCtx, rgbPictInfo->data, rgbPictInfo->linesize, 0, c->height, frame->data, frame->linesize);
  
  
  
      YuvToRgb(c, frame);
  
  }