The yuyv2iyuv function converts a single-channel YUYV (YUV 4:2:2)
image format to IYUV(4:2:0) format. Outputs of the function are separate
Y, U, and V planes. YUYV is a sub-sampled format, 1 set of YUYV value
gives 2 Y values and 1 U and V value each. U, V values of the odd rows
are dropped as U, V values are sampled once for 2 rows and 2 columns in
the IYUV(4:2:0) format.
API Syntax
template<int SRC_T, int DST_T, int ROWS, int COLS, int NPC=1, int XFCVDEPTH_IN = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_OUT_0 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_OUT_1 = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_OUT_2 = _XFCVDEPTH_DEFAULT>
void yuyv2iyuv(xf::cv::Mat<SRC_T, ROWS, COLS, NPC, XFCVDEPTH_IN> & _src, xf::cv::Mat<DST_T, ROWS, COLS, NPC, XFCVDEPTH_OUT_0> & _y_image, xf::cv::Mat<DST_T, ROWS/4, COLS, NPC, XFCVDEPTH_OUT_1> & _u_image, xf::cv::Mat<DST_T, ROWS/4, COLS, NPC, XFCVDEPTH_OUT_2> & _v_image)
Parameter Descriptions
The following table describes the template and the function parameters.
| Parameter | Description |
|---|---|
| SRC_T | Input pixel type. Only 16-bit, unsigned,1 channel is supported (XF_16UC1). |
| DST_T | Output 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 modes. |
| 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 | Depth of input image |
| XFCVDEPTH_OUT_0 | Depth of output image |
| XFCVDEPTH_OUT_1 | Depth of output image |
| XFCVDEPTH_OUT_2 | Depth of output image |
| _src | Input image of size (ROWS, COLS). |
| _y_image | Output Y plane of size (ROWS, COLS). |
| _u_image | Output U plane of size (ROWS/4, COLS). |
| _v_image | Output V plane of size (ROWS/4, COLS). |
Resource Utilization
The following table summarizes the resource utilization of YUYV to IYUV for different configurations, generated using Vivado HLS 2019.1 tool for the Xilinx 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 | 835 | 497 | 149 |
| 8 Pixel | 150 | 0 | 0 | 1428 | 735 | 210 |
Performance Estimate
The following table summarizes the performance of YUYV to IYUV for different configurations, as generated using Vivado HLS 2019.1 tool for the Xilinx Xczu9eg-ffvb1156-1-i-es1, to process a grayscale HD (1080x1920) image.
| Operating Mode | Latency Estimate |
|---|---|
| Max Latency (ms) | |
| 1 pixel operation (300 MHz) | 6.9 |
| 8 pixel operation (150 MHz) | 1.7 |