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Internal Modules
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86 SPRUHI7A – December 2012 – Revised June 2016
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High-Definition Video Processing Subsystem (HDVPSS)
1.2.5.2.2.1 Parameter Configuration
Region_height, Region_width, disp_pos_y, disp_pos_x are configured as shown in Figure 1-38 .
1.2.5.2.2.1.1 Disp_prior
Each region can be specified to have an inter-graphics-pipeline display priority level which may be used to
switch the order between two overlapping regions from two GRPX pipelines. The GRPX simply passes
these values along with each pixel data to the COMP module and the COMP uses it to reorder between
two GRPX data. This should be used only when both GRPX outputs are tied to the same display output
format and rate. The blended output is calculated differently (in the COMP module) for each region based
on each its priority level.
1.2.5.2.2.1.2 Disp_first_region
This bit needs to be set to `1` if the region is the first in vertical direction from top of the frame. Region0 in
Figure 1-38 is the first region in the frame.
1.2.5.2.2.1.3 Disp_last_region
This bit needs to be set to `1` if the region is the last in vertical direction from top of the frame. Region2 in
Figure 1-38 is the last region in the frame.
1.2.5.2.2.1.4 Scaler
The scaler used in GRPX module is consisted of a 5-tap/8-phase horizontal and a 4-tap/8-phase vertical
polyphase filters. It supports 0.25x – 4x scaling with a step size of 0.01. Individual regions can have a
different set of scaling parameters (coefficients, scale factor, and offset).
The input source format should be progressive if scaling of region is required.
If a region scaling is enabled, the first pixel location (origin) of the region serves as an anchor point for the
region display. Since the width and height of the region change after the scaling, application should take
care of the correct scaler attributes such that output of the scaler does not go out of the frame display.
Since the scaler stores one or more input lines before outputting any output lines, the following constraints
are imposed when multiple regions are displayed on the screen and scaling is enable:
1. One display line gap is required before a vertically up-scaled region
2. Two display line gap is required before a vertically down-scaled region
These constraints do not apply to the first region on the screen. This is illustrated in Figure 1-39 .
The minimum size of vertical region is one line, and no multiple regions on a same line is allowed (nor is
possible) per “region” graphics definition.