Video and Vision Processing Suite Intel® FPGA IP User Guide

ID 683329
Date 4/03/2023
Public

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Document Table of Contents
1. About the Video and Vision Processing Suite 2. Getting Started with the Video and Vision Processing IPs 3. Video and Vision Processing IPs Functional Description 4. Video and Vision Processing IP Interfaces 5. Video and Vision Processing IP Registers 6. Video and Vision Processing IPs Software Programming Model 7. Protocol Converter Intel® FPGA IP 8. 3D LUT Intel® FPGA IP 9. AXI-Stream Broadcaster Intel® FPGA IP 10. Chroma Key Intel® FPGA IP 11. Chroma Resampler Intel® FPGA IP 12. Clipper Intel® FPGA IP 13. Clocked Video Input Intel® FPGA IP 14. Clocked Video to Full-Raster Converter Intel® FPGA IP 15. Clocked Video Output Intel® FPGA IP 16. Color Space Converter Intel® FPGA IP 17. Deinterlacer Intel® FPGA IP 18. FIR Filter Intel® FPGA IP 19. Frame Cleaner Intel® FPGA IP 20. Full-Raster to Clocked Video Converter Intel® FPGA IP 21. Full-Raster to Streaming Converter Intel® FPGA IP 22. Genlock Controller Intel® FPGA IP 23. Generic Crosspoint Intel® FPGA IP 24. Genlock Signal Router Intel® FPGA IP 25. Guard Bands Intel® FPGA IP 26. Interlacer Intel® FPGA IP 27. Mixer Intel® FPGA IP 28. Pixels in Parallel Converter Intel® FPGA IP 29. Scaler Intel® FPGA IP 30. Stream Cleaner Intel® FPGA IP 31. Switch Intel® FPGA IP 32. Tone Mapping Operator Intel® FPGA IP 33. Test Pattern Generator Intel® FPGA IP 34. Video Frame Buffer Intel® FPGA IP 35. Video Streaming FIFO Intel® FPGA IP 36. Video Timing Generator Intel® FPGA IP 37. Warp Intel® FPGA IP 38. Design Security 39. Document Revision History for Video and Vision Processing Suite User Guide

29.3.3. Filter Behavior at Edge Boundaries

For the Scaler IP, when you select Polyphase and select N filter taps, (N-1)/2 of these taps are above (vertical scaling) or to the left of (horizontal scaling) the center tap of the filter. N/2 of the taps are below (vertical scaling) or to the right of (horizontal scaling) the center pixel.

When scaling pixels around the top, bottom, left or right edges (boundaries) of the image, the filter taps above, below, to the left of or to the right of the center pixel naturally attempt to sample pixels that do not exist as they are in off-screen locations. To avoid using undefined data in these taps, the scaler detects when any tap is off-screen and replaces the data in that tap with data from an on-screen pixel. The Edge behavior parameter allows you to choose between two methods for filling the off-screen taps:

  • Replicate edge pixels. The IP replicates the pixel closest to the edge to fill all off-screen taps
  • Mirror edge pixels. The pixels leading up to the image edge reflect into the off-screen area, just as if a mirror is at the edge of the image. The reflected pixel values fill any off-screen taps.

Edge mirroring for a filter with N taps requires a minimum input image size of N/2 pixels to successfully fill all off-screen taps. Input images smaller than this minimum create undefined outputs. Edge replication works for all image sizes, down to 1x1 pixel. You cannot swap between edge methods at runtime.

You can only select this parameter if you select Polyphase scaling. Nearest neighbor scaling has no filter and no off-screen taps. Bilinear scaling requires a 2 tap filter, but edge replication and edge mirroring give the same result when the number of taps is 2, so the parameter is not required.