Displaying YCbCr data and RGB data together using a hardware accelerator

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    • Displaying YCbCr data and RGB data together using a hardware accelerator

      Hello,

      I'm using a custom board with a STM32H745 MCU (STemWin v5.44). The color conversion routine is GUICC_M565.

      I need to display some JPEG data among other things.
      For converting JPEG data to RGB data I applied hardware JPEG decoder that converts JPEG data to YCbCr data and then I converted YCbCr data to RGB data by software.
      For displaying RGB data I applied DMA2D. I call _DrawBitmap() -> it calls LCD_DrawBitmap() -> it calls LCD_LL_DrawBitmap16bpp() in LCDConf.c.

      Here is a screen from the board displaying a JPEG data and some non-JPEG data (just a white text on a red background) above the JPEG picture. Works fine.


      The next I tried to do is to use DMA2D not only for displaying RGB data but for displaying YCbCr data without wasting time for convertion YCbCr to RGB.
      I modified some functions and now I've got the screen:


      RGB data is shown incorrect. I think there is some mess in data types when calling LCD_LL_DrawBitmap16bpp().

      So is it possible to display both data types (YCbCr and RGB) at the same time using DMA2D?

      Here's a part of the code:

      C Source Code

      1. /*** displaying some image and text from main.c ***/
      2. ...
      4. GUI_JPEG_SetpfDrawEx(JPEG_X_Draw);
      6. GUI_JPEG_Draw(_acpic, sizeof(_acpic), 0, 0);
      7. GUI_SetFont(GUI_FONT_20_ASCII);
      8. GUI_SetBkColor(GUI_RED);
      9. GUI_SetColor(GUI_WHITE);
      10. GUI_DispStringAt("A non-JPEG data", 100, 10);
      12. ...
      14. /*** _DrawBitmap() from main.c ***/
      15. void _DrawBitmap(int x, int y, void const * p, int xSize, int ySize, int BytesPerLine, int BitsPerPixel) {
      16. #if (GUI_WINSUPPORT)
      17. GUI_RECT r;
      18. #endif
      19. #if (GUI_WINSUPPORT)
      20. WM_ADDORG(x,y);
      21. r.x1 = (r.x0 = x) + xSize-1;
      22. r.y1 = (r.y0 = y) + ySize-1;
      23. WM_ITERATE_START(&r) {
      24. #endif
      25. LCD_DrawBitmap(x, y, xSize, ySize, 1, 1, BitsPerPixel, BytesPerLine, p, NULL);
      26. #if (GUI_WINSUPPORT)
      27. } WM_ITERATE_END();
      28. #endif
      29. }
      31. /*** JPEG_X_Draw() from main.c ***/
      32. int JPEG_X_Draw(GUI_GET_DATA_FUNC * pfGetData, void * p, int x0, int y0) {
      33. void * pData;
      34. uint32_t Size;
      35. JPEG_ConfTypeDef JPEG_Info;
      37. pData = *(void **)p;
      39. Size = *(uint32_t *)(p + 4);
      41. JPEG_Decode(&hjpeg, (uint32_t)pData, Size, (uint32_t)outBuf);
      43. while (Jpeg_HWDecodingEnd == 0);
      45. HAL_JPEG_GetInfo(&hjpeg, &JPEG_Info);
      47. chroma_sub_sampling = JPEG_Info.ChromaSubsampling;
      49. jpeg_draw = 1;
      51. _DrawBitmap(x0, y0, outBuf, Custom_JPEG_Info.JPEG_Info.ImageWidth, Custom_JPEG_Info.JPEG_Info.ImageHeight, Custom_JPEG_Info.BytesPerLine, Custom_JPEG_Info.BitsPerPixel);
      53. jpeg_draw = 0;
      55. return 0;
      56. }
      58. /*** LCD_LL_DrawBitmap16bpp() from LCDConf.c ***/
      59. ...
      61. extern uint8_t jpeg_draw;
      62. extern uint32_t chroma_sub_sampling;
      63. extern void DMA2D_CopyBufferJPEG(uint32_t *pSrc, uint32_t *pDst, uint16_t xsize, uint16_t ysize, uint32_t ChromaSampling, uint32_t OffLineSrc, uint32_t OffLineDst);
      65. ...
      67. void LCD_LL_DrawBitmap16bpp(int LayerIndex, int x, int y, U16 const * p, int xSize, int ySize, int BytesPerLine)
      68. {
      69. U32 BufferSize, AddrDst;
      70. int OffLineSrc, OffLineDst;
      72. switch (jpeg_draw) {
      73. case 0:
      74. BufferSize = GetBufferSize(LayerIndex);
      75. AddrDst = layer_prop[LayerIndex].address + BufferSize * layer_prop[LayerIndex].buffer_index + (y * layer_prop[LayerIndex].xSize + x) * layer_prop[LayerIndex].BytesPerPixel;
      76. OffLineSrc = (BytesPerLine / 2) - xSize;
      77. OffLineDst = layer_prop[LayerIndex].xSize - xSize;
      78. DMA2D_CopyBuffer(LayerIndex, (void *)p, (void *)AddrDst, xSize, ySize, OffLineSrc, OffLineDst);
      79. break;
      80. case 1:
      81. BufferSize = GetBufferSize(LayerIndex);
      82. AddrDst = layer_prop[LayerIndex].address + BufferSize * layer_prop[LayerIndex].buffer_index + (y * layer_prop[LayerIndex].xSize + x) * layer_prop[LayerIndex].BytesPerPixel;
      83. OffLineSrc = (BytesPerLine / 2) - xSize;
      84. OffLineDst = layer_prop[LayerIndex].xSize - xSize;
      85. DMA2D_CopyBufferJPEG((void *)p, (void *)AddrDst, xSize, ySize, chroma_sub_sampling, OffLineSrc, OffLineDst);
      86. break;
      87. }
      88. }
      90. /*** DMA2D_CopyBufferJPEG() from main.c***/
      91. void DMA2D_CopyBufferJPEG(uint32_t *pSrc, uint32_t *pDst, uint16_t xsize, uint16_t ysize, uint32_t ChromaSampling, uint32_t OffLineSrc, uint32_t OffLineDst)
      92. {
      93. uint32_t cssMode = LL_DMA2D_CSS_420, inputLineOffset = 0;
      95. LL_DMA2D_IsTransferOngoing(DMA2D);
      97. if(ChromaSampling == JPEG_420_SUBSAMPLING)
      98. {
      99. cssMode = LL_DMA2D_CSS_420;
      101. inputLineOffset = xsize % 16;
      102. if(inputLineOffset != 0)
      103. {
      104. inputLineOffset = 16 - inputLineOffset;
      105. }
      106. }
      107. else if(ChromaSampling == JPEG_444_SUBSAMPLING)
      108. {
      109. cssMode = LL_DMA2D_CSS_444;
      111. inputLineOffset = xsize % 8;
      112. if(inputLineOffset != 0)
      113. {
      114. inputLineOffset = 8 - inputLineOffset;
      115. }
      116. }
      117. else if(ChromaSampling == JPEG_422_SUBSAMPLING)
      118. {
      119. cssMode = LL_DMA2D_CSS_422;
      121. inputLineOffset = xsize % 16;
      122. if(inputLineOffset != 0)
      123. {
      124. inputLineOffset = 16 - inputLineOffset;
      125. }
      126. }
      128. /*##-1- Configure the DMA2D Mode, Color Mode and output offset #############*/
      129. LL_DMA2D_SetMode(DMA2D, LL_DMA2D_MODE_M2M_PFC);
      130. LL_DMA2D_SetOutputColorMode(DMA2D, LL_DMA2D_OUTPUT_MODE_RGB565);
      131. LL_DMA2D_SetLineOffset(DMA2D, OffLineDst);
      132. LL_DMA2D_FGND_SetColorMode(DMA2D, LL_DMA2D_INPUT_MODE_YCBCR);
      133. LL_DMA2D_FGND_SetAlphaMode(DMA2D, LL_DMA2D_ALPHA_MODE_REPLACE);
      134. LL_DMA2D_FGND_SetAlpha(DMA2D, 0xFF);
      135. LL_DMA2D_FGND_SetLineOffset(DMA2D, inputLineOffset);
      136. LL_DMA2D_FGND_SetRBSwapMode(DMA2D, LL_DMA2D_RB_MODE_REGULAR);
      137. LL_DMA2D_FGND_SetAlphaInvMode(DMA2D, LL_DMA2D_ALPHA_REGULAR);
      138. LL_DMA2D_FGND_SetChrSubSampling(DMA2D, cssMode);
      140. LL_DMA2D_FGND_SetMemAddr(DMA2D, (uint32_t)pSrc);
      141. LL_DMA2D_SetOutputMemAddr(DMA2D, (uint32_t)pDst);
      142. LL_DMA2D_SetNbrOfPixelsPerLines(DMA2D, xsize);
      143. LL_DMA2D_SetNbrOfLines(DMA2D, ysize);
      145. LL_DMA2D_Start(DMA2D);
      147. LL_DMA2D_IsTransferOngoing(DMA2D);
      148. }
      Display All

      Also LCDConf files in attach.

      Thank you.
      Files

      • LCDConf.zip

        (7.53 kB, downloaded 416 times, last: )
      Regards,

      Anthony