Scaler Settings - 2.4 English

Video Processing Subsystem Product Guide (PG231)

Document ID
Release Date
2.4 English
Figure 1. Top Level Scaler Options

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: 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 2. Scaler Tab

The parameters on the Scaler tab are as follows:

The Scaler comes in three different quality levels each at different levels of resource usage.
Bilinear scaling uses bilinear interpolation to calculate pixels.
Bicubic scaling is a little bit more demanding compared to bilinear scaling, and produces smoother pictures with less artifacts.
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.