Scaler Settings - 2.4 English

Video Processing Subsystem Product Guide (PG231)

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2.4 English
Figure 4-3: Top Level Scaler Options

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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.

Figure 4-4: Scaler Tab

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.