The iyuv2yuv4 function converts a single channel IYUV image to a
YUV444 format. Y plane is same for both the formats. The inputs are
separate U and V planes of IYUV image and the outputs are separate U and
V planes of YUV4 image. IYUV stores subsampled U,V values. YUV format
stores U and V values for every pixel. The same U, V values are
duplicated for 2 rows and 2 columns (2x2) pixels in order to get the
required data in the YUV444 format.
API Syntax
template<int SRC_T, int ROWS, int COLS, int NPC=1, int XFCVDEPTH_IN_0 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_IN_1 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_IN_2 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_IN_3 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_IN_4 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_IN_5 = _XFCVDEPTH_DEFAULT>
void iyuv2yuv4(xf::cv::Mat<SRC_T, ROWS, COLS, NPC, XFCVDEPTH_IN_0> & src_y, xf::cv::Mat<SRC_T, ROWS/4, COLS, NPC, XFCVDEPTH_IN_1> & src_u,xf::cv::Mat<SRC_T, ROWS/4, COLS, NPC, XFCVDEPTH_IN_2> & src_v,xf::cv::Mat<SRC_T, ROWS, COLS, NPC, XFCVDEPTH_IN_3> & _y_image, xf::cv::Mat<SRC_T, ROWS, COLS, NPC, XFCVDEPTH_IN_4> & _u_image, xf::cv::Mat<SRC_T, ROWS, COLS, NPC, XFCVDEPTH_IN_5> & _v_image)
Parameter Descriptions
The following table describes the template and the function parameters.
| Parameter | Description |
|---|---|
| SRC_T | Input pixel type. Only 8-bit, unsigned, 1-channel is supported (XF_8UC1). |
| ROWS | Maximum height of input and output image. |
| COLS | Maximum width of input and output image. Must be a multiple of 8, for 8 pixel mode. |
| NPC | Number of pixels to be processed per cycle; possible options are XF_NPPC1 and XF_NPPC8 for 1 pixel and 8 pixel operations respectively. |
| XFCVDEPTH_IN_0 | Depth of input image |
| XFCVDEPTH_IN_1 | Depth of input image |
| XFCVDEPTH_IN_2 | Depth of input image |
| XFCVDEPTH_IN_3 | Depth of input image |
| XFCVDEPTH_IN_4 | Depth of input image |
| XFCVDEPTH_IN_5 | Depth of input image |
| src_y | Input Y plane of size (ROWS, COLS). |
| src_u | Input U plane of size (ROWS/4, COLS). |
| src_v | Input V plane of size (ROWS/4, COLS). |
| _y_image | Output Y image of size (ROWS, COLS). |
| _u_image | Output U image of size (ROWS, COLS). |
| _v_image | Output V image of size (ROWS, COLS). |
Resource Utilization
The following table summarizes the resource utilization of IYUV to YUV4 for different configurations, generated using Vivado HLS 2019.1 tool for the Xczu9eg-ffvb1156-1-i-es1 FPGA, to process a HD (1080x1920) image.
| Operating Mode | Operating Frequency (MHz) | Utilization Estimate | ||||
|---|---|---|---|---|---|---|
| BRAM_18K | DSP_48Es | FF | LUT | CLB | ||
| 1 Pixel | 300 | 0 | 0 | 1398 | 870 | 232 |
| 8 Pixel | 150 | 0 | 0 | 2134 | 1214 | 304 |
Performance Estimate
The following table summarizes the performance of IYUV to YUV4 for different configurations, as generated using the Vivado HLS 2019.1 version tool for the Xczu9eg-ffvb1156-1-i-es1, to process a grayscale HD (1080x1920) image.
| Operating Mode | Latency Estimate |
|---|---|
| Max Latency (ms) | |
| 1 pixel operation (300 MHz) | 13.8 |
| 8 pixel operation (150 MHz) | 3.4 |