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Video Scaler v4.0 User Guide
UG805 March 1, 2011
Chapter 5:
Scaler Architectures
4:2:0 Special Requirements
When operating with 4:2:0, it is also important to include the following restriction:
when
scaling 4:2:0, the vertical scale factor applied at the vsf input must not be less than
(2
20
)*144/1080
. This restriction has been included because Direct Mode 4:2:0 requires
additional input buffering to align the chroma vertical aperture with the correct luma
vertical aperture. In a later release of the video scaler, this restriction will be removed.
Dual-Engine for Parallel YC Processing
For this architecture, separate engines are used to process Luma and Chroma channels in
parallel as shown in
Figure 5-2
.
For the Chroma channel, Cr and Cb are processed sequentially. Due to overheads in
completing each component, the chroma channel operations for each line require slightly
more time than the Luma operation. It is worth noting also that the Y and C operations do
not work in synchrony.
Triple-Engine for RGB/4:4:4 Processing
For this architecture, separate engines are used to process the three channels in parallel, as
shown in
Figure 5-3
.
For this case, all three channels are processed in synchrony.
X-Ref Target - Figure 5-2
Figure 5-2:
Internal Data Path Bitwidths for Dual-Engine YC Mode
Output
Line
Buffer
(C)
Luma
(Y)
Input
Line
Buffer
Scaler
Engine
(Y)
Output
Line
Buffer
(Y)
1* DataWidth
1*
DataWidth
1*DataWidth
2* DataWidth
Chroma
(Cr/Cb)
Input
Line
Buffer
Scaler
Engine
(C)
1*
DataWidth
1*
DataWidth
1* DataWidth
1*
DataWidth
2*DataWidth
video_data_in
1*DataWidth
video_da ta_out
X-Ref Target - Figure 5-3
Figure 5-3:
Internal Data Path Bitwidths for Triple-Engine RGB/4:4:4 Architecture
Output
Line
Buffer
(Ch2)
Ch1
Input
Line
Buffer
Scaler
Engine
(Ch1)
Output
Line
Buffer
(Ch1)
1* DataWidth
1*
DataWidth
1*DataWidth
3* DataWidth
Ch2
Input
Line
Buffer
Scaler
Engine
(Ch2)
1*
DataWidth
1*
DataWidth
1* DataWidth
1*
DataWidth
3*DataWidth
video_da ta_in
video_da ta_out
Output
Line
Buffer
(Ch3)
Ch3
Input
Line
Buffer
Scaler
Engine
(Ch3)
1*
DataWidth
1* DataWidth
1*DataWidth
Summary of Contents for LogiCORE IP
Page 1: ...LogiCORE IP Video Scaler v4 0 User Guide UG805 March 1 2011...
Page 6: ...Video Scaler v4 0 User Guide www xilinx com UG805 March 1 2011...
Page 14: ...14 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Preface About This Guide...
Page 18: ...18 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Chapter 1 Introduction...
Page 20: ...20 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Chapter 2 Overview...
Page 70: ...70 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Chapter 9 Performance...
Page 74: ...74 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Appendix A Use Cases...
Page 92: ...92 www xilinx com Video Scaler v4 0 User Guide UG805 March 1 2011 Appendix B Programmer Guide...
