X-Ref Target - Figure 4-3 |
When the Video Processing Functionality is chosen to be Scaler Only, the following options are available:
•Enable Color Space Conversion: When selected, the Scaler Only subcore supports run-time configurable color space conversion from RGB to YUV 4:4:4 and vice versa between the input and output video streams. Note that the coefficients are fixed and not programmable.
•Color Space Support: Select the color spaces for which support is desired. If YUV 4:2:2 is selected, basic horizontal chroma resampling is included. If YUV 4:2:0 is selected, basic vertical chroma resampling is also included. The combination of Enable Color Space Conversion and Color Space Support for RGB, YUV 4:4:4, YUV 4:2:2, YUV 4:2:0 basically turns the Scaler Only configuration into a scaler with any to any format conversion.
X-Ref Target - Figure 4-4 |
The parameters on the Scaler tab are as follows:
•Algorithm: The Scaler comes in three different quality levels each at different levels of resource usage.
°Bilinear: Bilinear scaling uses bilinear interpolation to calculate pixels.
°Bicubic: Bicubic scaling is a little bit more demanding compared to bilinear scaling, and produces smoother pictures with less artifacts.
°Polyphase: The picture quality (and resource usage) of a polyphase scaler depends largely on the number of filter taps used and number of filter phases used.
•Polyphase Filter Control: When polyphase filtering is selected, the horizontal and vertical taps and phases are defined here.
°Horizontal Taps: Select 6, 8, 10, or 12 horizontal filter taps.
°Vertical Taps: Select 6, 8, 10, or 12 vertical filter taps.
°Horizontal Phases: Only 64 phases is currently supported.
°Vertical Phases: Only 64 phases is currently supported.