Video and Vision Processing Suite Intel® FPGA IP User Guide

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ID 683329
Date 10/02/2023
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Document Table of Contents
Document Table of Contents x
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. Bits per Color Sample Adapter Intel FPGA IP 11. Chroma Key Intel® FPGA IP 12. Chroma Resampler Intel® FPGA IP 13. Clipper Intel® FPGA IP 14. Clocked Video Input Intel® FPGA IP 15. Clocked Video to Full-Raster Converter Intel® FPGA IP 16. Clocked Video Output Intel® FPGA IP 17. Color Space Converter Intel® FPGA IP 18. Deinterlacer Intel® FPGA IP 19. FIR Filter Intel® FPGA IP 20. Frame Cleaner Intel® FPGA IP 21. Full-Raster to Clocked Video Converter Intel® FPGA IP 22. Full-Raster to Streaming Converter Intel® FPGA IP 23. Genlock Controller Intel® FPGA IP 24. Generic Crosspoint Intel® FPGA IP 25. Genlock Signal Router Intel® FPGA IP 26. Guard Bands Intel® FPGA IP 27. Interlacer Intel® FPGA IP 28. Mixer Intel® FPGA IP 29. Pixels in Parallel Converter Intel® FPGA IP 30. Scaler Intel® FPGA IP 31. Stream Cleaner Intel® FPGA IP 32. Switch Intel® FPGA IP 33. Tone Mapping Operator Intel® FPGA IP 34. Test Pattern Generator Intel® FPGA IP 35. Video and Vision Monitor Intel FPGA IP 36. Video Frame Buffer Intel® FPGA IP 37. Video Frame Reader Intel FPGA IP 38. Video Frame Writer Intel FPGA IP 39. Video Streaming FIFO Intel® FPGA IP 40. Video Timing Generator Intel® FPGA IP 41. Warp Intel® FPGA IP 42. Design Security 43. Document Revision History for Video and Vision Processing Suite User Guide
1. About the Video and Vision Processing Suite x
1.1. Video and Vision Processing IPs Features 1.2. Device Family Support 1.3. Video and Vision Processing IPs Release Information 1.4. Lite versus Full IP Variants 1.5. Glossary of Video and Vision Terminology
2. Getting Started with the Video and Vision Processing IPs x
2.1. Video and Vision Processing IP Evaluation Time-out Behavior 2.2. Generating a Video and Vision Processing IP 2.3. Simulating the Video and Vision Processing IPs
3. Video and Vision Processing IPs Functional Description x
3.1. Auxiliary Control Packets 3.2. Latency 3.3. IP Debugging Features 3.4. Stall Behavior and Error Recovery 3.5. Avalon Streaming Video Protocol Versus Intel FPGA Streaming Video Protocol
5. Video and Vision Processing IP Registers x
5.1. Video and Vision Processing IP Control Examples
7. Protocol Converter Intel® FPGA IP x
7.1. About the Protocol Converter IP 7.2. Protocol Converter IP Parameters 7.3. Protocol Converter IP Functional Description 7.4. Protocol Converter IP Interfaces 7.5. Protocol Converter IP Registers 7.6. Protocol Converter IP Software API
7.1. About the Protocol Converter IP x
7.1.1. Protocol Converter IP Performance and Resources
8. 3D LUT Intel® FPGA IP x
8.1. About the 3D LUT Intel® FPGA IP 8.2. 3D LUT IP Parameters 8.3. 3D LUT IP Block Description 8.4. 3D LUT IP Registers 8.5. 3D LUT IP Software API
8.1. About the 3D LUT Intel® FPGA IP x
8.1.1. 3D LUT IP Features 8.1.2. 3D LUT IP Performance IP and Resource Information
8.3. 3D LUT IP Block Description x
8.3.1. 3D LUT IP Interfaces 8.3.2. 3D LUT IP Latency
9. AXI-Stream Broadcaster Intel® FPGA IP x
9.1. About the AXI-Stream Broadcaster IP 9.2. AXI-Stream Broadcaster IP Parameters 9.3. AXI-Stream Broadcaster IP Interfaces
9.1. About the AXI-Stream Broadcaster IP x
9.1.1. AXI-Stream Broadcaster IP Features 9.1.2. AXI-Stream Broadcaster IP Performance and Resources
10. Bits per Color Sample Adapter Intel FPGA IP x
10.1. About the Bits per Color Sample Adapter IP 10.2. Bits per Color Sample Adapter IP Parameters 10.3. Bits per Color Sample Adapter IP Interfaces 10.4. Bits per Color Sample Adapter IP Registers 10.5. Bits per Color Sample Adapter Software API
10.1. About the Bits per Color Sample Adapter IP x
10.1.1. Bits per Color Sample Adapter IP Performance and Resources
11. Chroma Key Intel® FPGA IP x
11.1. About the Chroma Key IP 11.2. Chroma Key IP Parameters 11.3. Chroma Key IP Interfaces 11.4. Chroma Key Replacement 11.5. Chroma Key IP Registers 11.6. Chroma Key IP Software API
11.1. About the Chroma Key IP x
11.1.1. Chroma Key IP Performance and Resources
12. Chroma Resampler Intel® FPGA IP x
12.1. About the Chroma Resampler IP 12.2. Chroma Resampler IP Parameters 12.3. Chroma Resampler IP Functional Description 12.4. Chroma Resampler IP Registers 12.5. Chroma Resampler IP Software API
12.1. About the Chroma Resampler IP x
12.1.1. Chroma Resampler Performance and Resources
12.3. Chroma Resampler IP Functional Description x
Chroma resampler algorithms Nearest Neighbor Filtered Color planes per pixel 12.3.1. Chroma Resampler IP Interfaces
13. Clipper Intel® FPGA IP x
13.1. About the Clipper IP 13.2. Clipper IP Parameters 13.3. Clipper IP Interfaces 13.4. Clipper IP Registers 13.5. Clipper IP Software API
13.1. About the Clipper IP x
13.1.1. Clipper IP Performance and Resources
14. Clocked Video Input Intel® FPGA IP x
14.1. About the Clocked Video Input IP 14.2. Initializing the Clocked Video Input IP 14.3. Clocked Video Input IP Parameters 14.4. Clocked Video Input IP Interfaces 14.5. Clocked Video Input IP Registers 14.6. Clocked Video Input IP Software API
14.1. About the Clocked Video Input IP x
14.1.1. Clocked Video Input IP Features 14.1.2. Clocked Video Input IP Performance and Resources
15. Clocked Video to Full-Raster Converter Intel® FPGA IP x
15.1. About the Clocked Video to Full-Raster Converter IP 15.2. Clocked Video to Full-Raster Converter Parameters 15.3. Clocked Video to Full-Raster Converter Block Description 15.4. Clocked Video Converter to Full-Raster IP Registers
15.1. About the Clocked Video to Full-Raster Converter IP x
15.1.1. Clocked Video to Full-Raster Converter Features 15.1.2. Clocked Video to Full-Raster Converter Performance and Resources
15.3. Clocked Video to Full-Raster Converter Block Description x
15.3.1. Clocked Video to Full-Raster Converter Interfaces
16. Clocked Video Output Intel® FPGA IP x
16.1. About the Clocked Video Output IP 16.2. Clocked Video Output IP Parameters 16.3. Clocked Video Output IP Functional Description 16.4. Clocked Video Output IP Interfaces 16.5. Clocked Video Output IP Registers 16.6. Clocked Video Output IP Software API
16.1. About the Clocked Video Output IP x
16.1.1. Clocked Video Output IP Performance and Resources 16.1.2. Clocked Video Output IP Features
17. Color Space Converter Intel® FPGA IP x
17.1. About the Color Space Converter IP 17.2. Color Space Converter IP Parameters 17.3. Color Space Converter IP Functional Description 17.4. Color Space Converter IP Registers 17.5. Color Space Converter IP Software API
17.1. About the Color Space Converter IP x
17.1.1. Color Space Converter IP Features 17.1.2. Color Space Converter IP Performance and Resources
17.3. Color Space Converter IP Functional Description x
17.3.1. Color Space Converter IP Interfaces
18. Deinterlacer Intel® FPGA IP x
18.1. About the Deinterlacer IP 18.2. Deinterlacer Parameters 18.3. Deinterlacer Interfaces 18.4. Deinterlacer IP Registers 18.5. Deinterlacer IP Software API
18.1. About the Deinterlacer IP x
18.1.1. Deinterlacer Performance and Resources
19. FIR Filter Intel® FPGA IP x
19.1. About the FIR Filter 19.2. FIR Filter Parameters 19.3. FIR Filter IP Operation 19.4. FIR Filter Interfaces 19.5. FIR Filter Registers 19.6. FIR Filter IP Software API
19.1. About the FIR Filter x
19.1.1. FIR Filter IP Performance and Resources
19.3. FIR Filter IP Operation x
19.3.1. FIR Filter Processing 19.3.2. FIR Filter Precision 19.3.3. FIR Coefficient Specification 19.3.4. FIR Filter Symmetry 19.3.5. Result to Output Data Type Conversion
19.3.4. FIR Filter Symmetry x
19.3.4.1. No Symmetry 19.3.4.2. Horizontal Symmetry 19.3.4.3. Vertical Symmetry 19.3.4.4. Horizontal and Vertical Symmetry 19.3.4.5. Diagonal Symmetry
20. Frame Cleaner Intel® FPGA IP x
20.1. About the Frame Cleaner IP 20.2. Frame Cleaner IP Parameters 20.3. Frame Cleaner IP Functional Description 20.4. Frame Cleaner IP Interfaces 20.5. Frame Cleaner IP Registers 20.6. Frame Cleaner IP Software API
20.1. About the Frame Cleaner IP x
20.1.1. Frame Cleaner IP Performance and Resources
21. Full-Raster to Clocked Video Converter Intel® FPGA IP x
21.1. About the Full-Raster to Clocked Video Converter 21.2. Full Raster to Clocked Video Converter Parameters 21.3. Full-Raster to Clocked Video Converter Block Description 21.4. Full-Raster to Clocked Video Converter Registers
21.1. About the Full-Raster to Clocked Video Converter x
21.1.1. Full-Raster to Clocked Video Converter Features 21.1.2. Full-Raster to Clocked Video Converter Performance and Resource Utilization
21.3. Full-Raster to Clocked Video Converter Block Description x
21.3.1. Full Raster to Clocked Video Converter Interfaces
22. Full-Raster to Streaming Converter Intel® FPGA IP x
22.1. About the Full-Raster to Streaming Converter IP 22.2. Full-Raster to Streaming Converter Parameters 22.3. Full-Raster to Streaming Converter Block Description
22.1. About the Full-Raster to Streaming Converter IP x
22.1.1. Full-Raster to Streaming Converter Features 22.1.2. Full-Raster to Streaming Converter Performance and Resources
22.3. Full-Raster to Streaming Converter Block Description x
22.3.1. Full-Raster to Streaming Converter Interfaces
23. Genlock Controller Intel® FPGA IP x
23.1. About the Genlock Controller IP 23.2. Genlock Controller IP Parameters 23.3. Genlock Controller IP Functional Description 23.4. Using Genlock Controller IP Software 23.5. Genlock Controller IP Registers 23.6. Genlock Controller IP Software API
23.1. About the Genlock Controller IP x
23.1.1. Genlock Controller IP Performance and Resources
23.3. Genlock Controller IP Functional Description x
23.3.1. Genlock Controller IP Interfaces
23.4. Using Genlock Controller IP Software x
23.4.1. Achieving Genlock Controller Free Running (for Initialization or from Lock to Reference Clock N) 23.4.2. Locking to Reference Clock N (from Genlock Controller IP free running) 23.4.3. Setting the VCXO hold over 23.4.4. Restarting the Genlock Controller IP 23.4.5. Locking to Reference Clock N New (from Locking to Reference Clock N Old) 23.4.6. Changing to Reference Clock or VCXO Base Frequencies (switch between p50 and p59.94 video formats and vice-versa) 23.4.7. Disturbing a Reference Clock (a cable pull)
24. Generic Crosspoint Intel® FPGA IP x
24.1. About the Generic Crosspoint IP 24.2. Generic Crosspoint IP Parameters 24.3. Generic Crosspoint IP Interfaces 24.4. Generic Crosspoint IP Registers 24.5. Generic Crosspoint IP Software API
24.1. About the Generic Crosspoint IP x
24.1.1. Generic Crosspoint IP Features 24.1.2. Generic Crosspoint Performance and Resources
25. Genlock Signal Router Intel® FPGA IP x
25.1. About the Genlock Signal Router IP 25.2. Genlock Signal Router IP Parameters 25.3. Genlock Signal Router IP Interfaces 25.4. Genlock Signal Router IP Registers 25.5. Genlock Signal Router IP Software API
25.1. About the Genlock Signal Router IP x
25.1.1. Genlock Signal Router IP Features 25.1.2. Genlock Signal Router IP Performance and Resources
26. Guard Bands Intel® FPGA IP x
26.1. About the Guard Bands IP 26.2. Guard Bands IP Parameters 26.3. Guard Bands IP Interfaces 26.4. Guard Bands IP Registers 26.5. Guard Bands IP Software API
26.1. About the Guard Bands IP x
26.1.1. Guard Bands IP Performance and Resources
27. Interlacer Intel® FPGA IP x
27.1. About the Interlacer IP 27.2. Interlacer IP Parameters 27.3. Interlacer IP Functional Description 27.4. Interlacer IP Registers 27.5. Interlacer IP Software API
27.1. About the Interlacer IP x
27.1.1. Interlacer IP Performance and Resources
27.3. Interlacer IP Functional Description x
27.3.1. Interlacer IP Interfaces
28. Mixer Intel® FPGA IP x
28.1. About the Mixer IP 28.2. Mixer IP Parameters 28.3. Mixer IP Functional Description 28.4. Mixer IP Registers 28.5. Mixer IP Software API
28.1. About the Mixer IP x
28.1.1. Mixer IP Performance and Resources
28.3. Mixer IP Functional Description x
28.3.1. Mixer IP Interfaces
29. Pixels in Parallel Converter Intel® FPGA IP x
29.1. About the Pixels in Parallel Converter IP 29.2. Pixels in Parallel Converter IP Parameters 29.3. Pixels in Parallel Converter Interfaces 29.4. Pixels in Parallel Converter Registers 29.5. Pixels in Parallel Converter IP Software API
29.1. About the Pixels in Parallel Converter IP x
29.1.1. Pixels in Parallel Converter IP Performance and Resources
30. Scaler Intel® FPGA IP x
30.1. About the Scaler 30.2. Scaler IP Parameters 30.3. Scaler IP Functional Description 30.4. Scaler IP Registers 30.5. Scaler IP Software API
30.1. About the Scaler x
30.1.1. Scaler IP Performance and Resources
30.2. Scaler IP Parameters x
30.2.1. Scaler Maximum Resolution
30.3. Scaler IP Functional Description x
30.3.1. Coefficient Selection 30.3.2. Coefficient Quantization 30.3.3. Filter Behavior at Edge Boundaries 30.3.4. Partial Frame Scaling 30.3.5. 422 and 420 Chroma Sampled Data Scaling 30.3.6. Scaler IP Interfaces
30.3.1. Coefficient Selection x
30.3.1.1. Updating Scaler IP Runtime Coefficients
31. Stream Cleaner Intel® FPGA IP x
31.1. About the Stream Cleaner IP 31.2. Stream Cleaner IP Parameters 31.3. Stream Cleaner IP Functional Description
31.1. About the Stream Cleaner IP x
31.1.1. Stream Cleaner IP Performance and Resources
31.3. Stream Cleaner IP Functional Description x
31.3.1. Stream Cleaner IP Interfaces
32. Switch Intel® FPGA IP x
32.1. About the Switch IP 32.2. Switch IP Parameters 32.3. Switch IP Functional Description 32.4. Switch IP Registers 32.5. Switch IP Software API
32.1. About the Switch IP x
32.1.1. Switch IP Performance and Resources
32.3. Switch IP Functional Description x
32.3.1. Switch IP Latency 32.3.2. Switch IP Interfaces
33. Tone Mapping Operator Intel® FPGA IP x
33.1. About the Tone Mapping Operator IP 33.2. TMO IP Parameters 33.3. TMO IP Block Description 33.4. TMO IP Registers 33.5. TMO IP Software API
33.1. About the Tone Mapping Operator IP x
33.1.1. TMO IP Features 33.1.2. TMO IP Performance and Resource Utilization
33.3. TMO IP Block Description x
33.3.1. TMO IP Interfaces 33.3.2. TMO IP Latency
34. Test Pattern Generator Intel® FPGA IP x
34.1. About the Test Pattern Generator IP 34.2. Test Pattern Generator IP Parameters 34.3. Test Pattern Generator IP Functional Description 34.4. Test Pattern Generator IP Registers 34.5. Test Pattern Generator IP Software API
34.1. About the Test Pattern Generator IP x
34.1.1. Test Pattern Generator IP Performance and Resources
34.3. Test Pattern Generator IP Functional Description x
34.3.1. Test Pattern Generator IP Interfaces
35. Video and Vision Monitor Intel FPGA IP x
35.1. About the Video and Vision Monitor IP 35.2. Video and Vision Monitor IP Parameters 35.3. Video and Vision Monitor IP Functional Description 35.4. Video and Vision Monitor IP Registers 35.5. Video and Vision Monitor Software API
35.1. About the Video and Vision Monitor IP x
35.1.1. Video and Vision Monitor IP Performance and Resources
35.3. Video and Vision Monitor IP Functional Description x
35.3.1. Video and Vision Monitor IP Interfaces
36. Video Frame Buffer Intel® FPGA IP x
36.1. About the Video Frame Buffer IP 36.2. Video Frame Buffer IP Parameters 36.3. Video Frame Buffer IP Functional Description 36.4. Video Frame Buffer IP Registers 36.5. Video Frame Buffer IP Software API
36.1. About the Video Frame Buffer IP x
36.1.1. Video Frame Buffer Performance and Resources
36.3. Video Frame Buffer IP Functional Description x
36.3.1. Video Frame Buffer IP Interfaces
37. Video Frame Reader Intel FPGA IP x
37.1. About the Video Frame Reader IP 37.2. Video Frame Reader IP Parameters 37.3. Video Frame Reader IP Functional Description 37.4. Video Frame Reader IP Registers 37.5. Video Frame Reader IP Software API
37.1. About the Video Frame Reader IP x
37.1.1. Video Frame Reader IP Performance and Resources
37.3. Video Frame Reader IP Functional Description x
37.3.1. Video Frame Reader IP Interfaces
38. Video Frame Writer Intel FPGA IP x
38.1. About the Video Buffer Writer IP 38.2. Video Frame Writer IP Parameters 38.3. Video Frame Writer IP Functional Description 38.4. Video Frame Writer IP Registers 38.5. Video Frame Writer IP Software API
38.1. About the Video Buffer Writer IP x
38.1.1. Video Frame Writer IP Performance and Resources
38.3. Video Frame Writer IP Functional Description x
38.3.1. Video Frame Writer IP Interfaces
39. Video Streaming FIFO Intel® FPGA IP x
39.1. About the Video Streaming FIFO IP 39.2. Video Streaming FIFO IP Parameters 39.3. Video Streaming FIFO IP Interfaces
39.1. About the Video Streaming FIFO IP x
39.1.1. Video Streaming FIFO IP Performance and Resources
40. Video Timing Generator Intel® FPGA IP x
40.1. About the Video Timing Generator IP 40.2. Video Timing Generator IP Parameters 40.3. Video Timing Generator IP Functional Description 40.4. Video Timing Generator IP Interfaces 40.5. Video Timing Generator IP Registers 40.6. Video Timing Generator IP Software API
40.1. About the Video Timing Generator IP x
40.1.1. Video Timing Generator IP Features 40.1.2. Video Timing Generator IP Performance and Resources
41. Warp Intel® FPGA IP x
41.1. About the Warp IP 41.2. Warp IP Parameters 41.3. Warp IP Block Description 41.4. Warp IP Registers 41.5. Warp IP Software API
41.1. About the Warp IP x
41.1.1. Warp IP Features 41.1.2. Warp IP Performance and Resource Utilization
41.3. Warp IP Block Description x
41.3.1. Block Cache Tool 41.3.2. Warp IP Interfaces 41.3.3. Warp IP Latency 41.3.4. External Memory for Warp IP
41.5. Warp IP Software API x
41.5.1. Using Warp IP Software 41.5.2. Warp IP Software Code Examples
42. Design Security x
42.1. Memory Subsystems 42.2. Considering Design Security
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. Bits per Color Sample Adapter Intel FPGA IP
11. Chroma Key Intel® FPGA IP
12. Chroma Resampler Intel® FPGA IP
13. Clipper Intel® FPGA IP
14. Clocked Video Input Intel® FPGA IP
15. Clocked Video to Full-Raster Converter Intel® FPGA IP
16. Clocked Video Output Intel® FPGA IP
17. Color Space Converter Intel® FPGA IP
18. Deinterlacer Intel® FPGA IP
19. FIR Filter Intel® FPGA IP
20. Frame Cleaner Intel® FPGA IP
21. Full-Raster to Clocked Video Converter Intel® FPGA IP
22. Full-Raster to Streaming Converter Intel® FPGA IP
23. Genlock Controller Intel® FPGA IP
24. Generic Crosspoint Intel® FPGA IP
25. Genlock Signal Router Intel® FPGA IP
26. Guard Bands Intel® FPGA IP
27. Interlacer Intel® FPGA IP
28. Mixer Intel® FPGA IP
29. Pixels in Parallel Converter Intel® FPGA IP
30. Scaler Intel® FPGA IP
31. Stream Cleaner Intel® FPGA IP
32. Switch Intel® FPGA IP
33. Tone Mapping Operator Intel® FPGA IP
34. Test Pattern Generator Intel® FPGA IP
35. Video and Vision Monitor Intel FPGA IP
36. Video Frame Buffer Intel® FPGA IP
37. Video Frame Reader Intel FPGA IP
38. Video Frame Writer Intel FPGA IP
39. Video Streaming FIFO Intel® FPGA IP
40. Video Timing Generator Intel® FPGA IP
41. Warp Intel® FPGA IP
42. Design Security
43. Document Revision History for Video and Vision Processing Suite User Guide

12.3. Chroma Resampler IP Functional Description

Chroma resampler algorithms

The chroma resampler implements four basic resampling operations:

  • Horizontal upsampling: 4:2:2 -> 4:4:4
  • Horizontal downsampling: 4:4:4 -> 4:2:2
  • Vertical upsampling: 4:2:0 -> 4:2:2
  • Vertical downsampling: 4:2:2 -> 4:2:0

For conversions between 4:4:4 and 4:2:0 the relevant horizontal and vertical sampling operations chain automatically to achieve the correct end result. The chroma resampler supports three different algorithms for each resampling operation; nearest neighbor, bilinear and filtered. The three algorithms vary in the level of visual quality provided, the chroma siting, and the resources for implementation.

Nearest Neighbor

Nearest neighbor is the lowest quality resampling algorithm, with the lowest device resource usage. For horizontal downsampling (4:4:4 -> 4:2:2) it drops every other Cb and Cr sample within the video line. For horizontal upsampling (4:2:2 -> 4:4:4) it repeats each Cb and Cr sample. The nearest neighbor algorithm uses left siting (co-siting) for the 4:2:2 chroma samples – both the Cb and Cr samples from the even indexed Y samples are retained during downsampling.

Figure 20. Nearest Neighbor

The nearest neighbor algorithm works in the same way for vertical resampling. For vertical downsampling (4:2:2 -> 4:2:0) the IP discards the chroma data from every other video line. For upsampling (4:2:0 -> 4:2:2) the IP repeats the chroma data for two lines of luma data. The nearest neighbor algorithm uses top siting (cositing) for both the Cb and Cr planes. The IP preserves chroma data from lines 0, 2, 4, etc in downsampling. The IP discards the data from lines 1, 3, 5, etc.

Figure 21. Nearest Neighbor
Bilinear

The bilinear algorithm offers a midpoint between visual image quality and device resource cost. You can parameterize the bilinear algorithm to use either left or centre horizontal siting of the chroma data, and top or centre vertical siting of the choma data.

Top or left chroma siting is the simpler of the two algorithm options. Top or left downsampling using the bilinear algorithm is exactly equivalent to nearest neighbour downsampling. The IP discards the chroma data from the odd indexed pixels. Top or left upsampling recreates the chroma data for odd indexed pixels by taking the average of the chroma samples for the two neighbouring even indexed pixels. The IP takes the chroma values for the even indexed pixels directly from the input values. Both the nearest neighbour algorithm and the bilinear algorithm with top or left chroma siting are fully reversible. The upsampling algorithm creates new data without altering the values of the any the original input data. The downsampling algorithm simply discards the values that the upsampling algorithm creates.

Centre chroma sampling for the bilinear algorithm is more complex and is not reversible because the IP alters all of the chroma values during both the upsample and downsample processes.
Figure 22. BilinearThe figure and equations show how the IP calculates the bilinear resampled chroma for horizontal upsampling (4:2:4 -> 4:4:4) and downsampling (4:4:4 -> 4:2:2) using center chroma siting.

The bilinear algorithm using center siting works in the same way for vertical upsampling (4:2:0 -> 4:2:2) and downsampling (4:2:2 -> 4:2:0).

Filtered

The filtered algorithm is the most computationally expensive and device resource intense algorithm, but it offers increased visual quality. You can parameterize the filtered algorithm to use either left or center horizontal siting of the chroma data, and top or center vertical siting of the chroma data.

For downsampling conversions (4:2:2 -> 4:2:0 and 4:4:4 -> 4:2:2) the filtered algorithm applies an 8-tap Lanczos2 resampling filter to generate the downsampled data. The IP applies different phase shifts to the Lanczos2 function when generating the coefficients for each chroma siting option. For top and left chroma siting, the IP applies a phase shift of 0 pixels to the Lanczos2 coefficients. For center chroma siting the phase shift is +0.5 pixels.

For upsampling conversions (4:2:0 -> 4:2:2 and 4:2:2 -> 4:4:4) the filtered algorithm applies a 4-tap Lanczos2 resampling filter to generate the upsampled data. For top/left chroma siting, phase shifts of 0 and 0.5 pixels are applied to the Lanczos2 coefficients for the even and odd indexed chroma samples respectively.For center chroma siting the phases shifts are -0.25 and +0.25 pixels.

You can also turn on luma adaption for upsampling conversions. This feature further increases device resource usage but may reduce color bleed around edges when compared to the default filtered algorithm. The feature is the only chroma resampler to implement some logic in DSP blocks. When you turn on luma adaption, the IP compares differences between successive luma samples to an edge threshold to detect significant edges. In areas where the IP detects edges, you can shift the phase of the Lanczos-2 filter by up to 0.25 pixels to the left or right. This shift weights the resulting chroma samples more intensely towards the more appropriate side of the edge.

Color planes per pixel

Most Video and Vision Processing IPs allow you to select the number of color planes per pixel, but the chroma resampler does not have that parameter and sets the value automatically. The number of color planes per pixel is a function of the chroma resampling conversions that you select, which determine the chroma sampling formats that are supported at the input and output interfaces. 4:4:4 and 4:2:0 chroma samplings both require three color panes per pixel. 4:2:2 only requires 2 color planes. 4:2:2 can be transmitted through a link with 3 color planes, with the planes in the most significant bits of each pixel unused.

If you select any of the following chroma sampling conversions, the input interface uses three color planes per pixel, otherwise it uses two color planes:

  • 4:2:0 passthrough
  • 4:2:0 to 4:4:4
  • 4:2:0 to 4:2:2
  • 4:4:4 passthrough
  • 4:4:4 to 4:2:2
  • 4:4:4 to 4:2:0

If you select any of the following chroma sampling conversions, the output interface uses three color planes per pixel, otherwise it uses two color planes:

  • 4:2:0 passthrough
  • 4:2:0 to 4:4:4
  • 4:4:4 passthrough
  • 4:4:4 to 4:2:0
  • 4:2:2 to 4:4:4
  • 4:2:2 to 4:2:0

Section Content
Chroma Resampler IP Interfaces

Level Two Title