Mode filter - 2024.1 English

Vitis Libraries

Release Date
2024-05-30
Version
2024.1 English

Mode filter is a non-linear digital filter which improves noise reduction. This implements filter operation with given size of N by computing mode for all the pixels in an NxN window.

API Syntax

template <int FILTER_SIZE, int BORDER_TYPE, int TYPE, int ROWS, int COLS, int NPC = 1, int XFCVDEPTH_IN = _XFCVDEPTH_DEFAULT, int XFCVDEPTH_OUT = _XFCVDEPTH_DEFAULT>
void modefilter(xf::cv::Mat<TYPE, ROWS, COLS, NPC, XFCVDEPTH_IN>& _src, xf::cv::Mat<TYPE, ROWS, COLS, NPC, XFCVDEPTH_OUT>& _dst)

Parameter Descriptions

The following table describes the template and the function parameters.

Table 678 Table Mode filter Parameter Description
Parameter Description
FILTER_SIZE Window size of the hardware filter for which the hardware kernel will be built. This can be any odd positive integer greater than 1.
BORDER_TYPE The way in which borders will be processed in the hardware kernel. Currently, only XF_BORDER_REPLICATE is supported.
TYPE Input and Output pixel type. Only 8-bit, unsigned, 1 or 3 channels are supported (XF_8UC1 and XF_8UC3)
ROWS Number of rows in the image being processed.
COLS Number of columns in the image being processed. Must be a multiple of 8, for 8-pixel operation.
NPC Number of pixels to be processed in parallel. Options are XF_NPPC1 (for 1 pixel processing per clock), XF_NPPC8 (for 8 pixel processing per clock
XFCVDEPTH_IN Depth of the input image.
XFCVDEPTH_OUT Depth of the output image.
_src Input image.
_dst Output image.

Resource Utilization

The following table summarizes the resource utilization of the Mode filter function for XF_NPPC1 configurations, generated using Vitis HLS 2020.2 version tool.

Table 679 Table Mode filter Function Resource Utilization Summary
Operating Mode FILTER_SIZE Operating Frequency (MHz) Utilization Estimate
LUTs FFs DSPs BRAMs
1 pixel 3 300 628 900 0 3
1 pixel 5 300 2579 4070 0 5
1 pixel 7 300 7852 14065 0 7

Performance Estimate

The following table summarizes performance estimates of Mode filter function on Vitis HLS 2020.2 version tool.

Table 680 Table Mode filter Function Performance Estimate Summary
Operating Mode FILTER_SIZE Operating Frequency (MHz) Input Image Size Latency Estimate Max (ms)
1 pixel 3 300 1920x1080 6.99
1 pixel 5 300 1920x1080 7.00
1 pixel 7 300 1920x1080 7.15