Bi-lateral Filter
Latest research in the field of image processing has shown that the bilateral filter is one of the most popular filters designed for noise suppression while preserving edges at the same time. The Input Video Data Buffer reads the data from the source and provides a pixel array of configurable kernel size to the filter kernel. The Filter Kernel harnesses both the photometric as well as geometric relation between the neighboring pixels then use this information to calculate the filter coefficients for each pixel in run time. The Pipeline Controller ensures synchronicity of all the modules for achieving real time bandwidth.
Following are the mathematical operations involved:
First equation is the complete mathematical expression between the o(x), the filtered pixel of image, o at location, x in terms of the pixels lying around location m within a kernel k, of image i and the photometric coefficients s and geometric coefficients c.
Second and third equations provide the expression for photometric and geometric coefficients at location x with respect to location m using the respective variances.
Fourth equation is the expression for the normalization factor for the kernel.
Features
- High Configurability
- Ip/Op Video Resolution, fully Customizable 720 x 576, 640 x 480, 320 x 256
- Both 24 bit and 30 bit data formats supported
- Kernel Width & Height range 3-8 rows and cols
- Run time con-figurability of Photometric and Geometric Variances
- Latency : less than 0.4m secs for 720×576 resolution, 30 bit YCBCR Video Stream
- Throughput : Real Time performance tested for PAL-B 25fps
