Skip to content
Codes for transforming/resizing/croping picture
C++ Makefile
Branch: master
Clone or download


The EZDVPP encapsulates the DVPP APIs to simplify the calls. The main functions include:

Image format conversion (including YUV to JPG, and JPEG to YUV), image cropping, and image resizing.

The methods of using EZDVPP APIs are as follows:

  • Image format conversion

    • Convert YUV data streams obtained by the camera into JPG data streams.

      // Interface usage example: YUV-to-JPG conversion
      typedef struct DvppOutputInfo {
      //output buffer
      unsigned char *pbuf;
      //size of output buffer
      unsigned int size;
      } DvppOutput;
      Ascend::Utils::DvppProcess *pDvppProcess=nullptr;
      // Initialization parameter for converting YUV into JPG
      dvppToJpgPara.format = JPGENC_FORMAT_NV12;
      dvppToJpgPara.level = DVPP_TO_JPG_QUALITY_PARAMETER;
      dvppToJpgPara.resolution.height = height;
      dvppToJpgPara.resolution.width = width;
      // Instantiated class variable
      pDvppProcess = new Ascend::Utils::DvppProcess(dvppToJpgPara);
      // Conversion interface. dvppOutput.pbuf is the converted JPG data.
    • JPEG-to-YUV conversion: Convert an input JPEG image into a YUV image. The JPEG (color space: YUV, subsample: 444/422/420/400) supports only Huffman coding and does not support arithmetic coding, progressive coding, or JPEG 2000 format.

      Interface 4: JPEG-to-YUV conversion
      struct DvppJpegDOutput {
          unsigned char *buffer;  // output buffer
          uint32_t buffer_size;  // output buffer size
          uint32_t width;  // the width of output image
          uint32_t height;  // the height of output image
          uint32_t aligned_width;  // the aligned width of output image
          uint32_t aligned_height;  // the aligned height of output image
          VpcInputFormat image_format;  //output image format
      ascend::utils::DvppJpegDInPara dvpp_to_yuv_para;
      dvpp_to_yuv_para.is_convert_yuv420 = true;
      ascend::utils::DvppProcess dvpp_yuv_process(dvpp_to_yuv_para);
      ascend::utils::DvppJpegDOutput dvpp_out_data = { 0 };
  • Image cropping, image resizing, and format conversion

    Convert the input YUV444SP/YUV422SP/YUV420SP/YUV444Packed/YUV422Packed/BGR/RGB/ARGB/ABGR/RGBA/BGRA image into a YUV420SP image and perform image cropping and resizing.

    // Interface usage example: format conversion and image resizing (In this sample code, image cropping is not performed.)
    struct DvppVpcOutput {
        uint8_t *buffer;
        uint32_t size;
    DvppBasicVpcPara resize_para;
    resize_para.input_image_type = INPUT_BGR;
    // get original image size and set to resize parameter
    int32_t width = image_handle->image_info.width;
    int32_t height = image_handle->image_info.height;
    // set source resolution ratio
    resize_para.src_resolution.width = width;
    resize_para.src_resolution.height = height;
    // crop parameters, only resize, no need crop, so set original image size
    // set crop left-top point (need even number)
    resize_para.crop_left = 0;
    resize_para.crop_up = 0;
    // set crop right-bottom point (need odd number)
    uint32_t crop_right = ((width >> 1) << 1) - 1;
    uint32_t crop_down = ((height >> 1) << 1) - 1;
    resize_para.crop_right = crop_right;
    resize_para.crop_down = crop_down;
    // set destination resolution ratio (need even number)
    uint32_t dst_width = ((image_handle->console_params.model_width) >> 1) << 1;
    uint32_t dst_height = ((image_handle->console_params.model_height) >> 1) << 1;
    resize_para.dest_resolution.width = dst_width;
    resize_para.dest_resolution.height = dst_height;
    // set input image align or not
    resize_para.is_input_align = false;
    // call
    DvppProcess dvpp_resize_img(resize_para);
    DvppVpcOutput dvpp_output;
    ret = dvpp_resize_img.DvppBasicVpcProc(
          image_handle->, image_handle->image_info.size,
You can’t perform that action at this time.