39.6.3.3 Window Position, Size, Scaling and Striding Attributes

  • XPOS and YPOS fields—Defines the position of the overlay window.
  • XSIZE and YSIZE fields—Defines the size of the displayed window.
  • XMEMSIZE and YMEMSIZE fields—Defines the size of the image frame buffer.
  • XSTRIDE and PSTRIDE fields—Defines the line and pixel striding.
  • XFACTOR and YFACTOR fields—Defines the scaling ratio.

The position and size attributes are to be programmed to keep the window within the display area.

When the Color Lookup Table mode is enabled, the restrictions detailed in the following table apply on the horizontal and vertical window sizes.

Table 39-6. Color Lookup Table Mode and Window Size
CLUT Mode X-Y Size Requirement
1 bpp Multiple of 8 pixels
2 bpp Multiple of 4 pixels
4 bpp Multiple of 2 pixels
8 bpp Free size

Pixel striding is disabled when CLUT mode is enabled.

Table 39-7. Window Size
Mode X-Y Requirement, Scaling Turned Off X-Y Requirement, Scaling Turned On XMEM_SIZE-YMEM_SIZE Requirement, Scaling Turned On
ARGB/TRGB/CLUT Free size XSIZE ≥ 3 pixels

YSIZE ≥ 3 pixels

XMEM_SIZE ≥ 3 pixels

YMEM_SIZE ≥ 3 pixels

AYCbCr 4:4:4 Free size XSIZE ≥ 3 pixels

YSIZE ≥ 3 pixels

XMEM_SIZE ≥ 3 pixels

YMEM_SIZE ≥ 3 pixels

YCbCr 4:2:2 Packed XSIZE ≥ 6 pixels

Free YSIZE

XSIZE ≥ 6 pixels

YSIZE ≥ 3 pixels

XMEM_SIZE ≥ 6 pixels, even

YMEM_SIZE ≥ 3 pixels

YCbCr 4:2:2 Semiplanar XSIZE ≥ 6 pixels

Free YSIZE

XSIZE ≥ 6 pixels

YSIZE ≥ 3 pixels

XMEM_SIZE ≥ 6 pixels

YMEM_SIZE ≥ 3 pixels

YCbCr 4:2:2 Planar XSIZE ≥ 6 pixels

Free YSIZE

XSIZE ≥ 6 pixels

YSIZE ≥ 3 pixels

XMEM_SIZE ≥ 6 pixels

YMEM_SIZE ≥ 3 pixels

YCbCr 4:2:0 Semiplanar XSIZE ≥ 6 pixels

YSIZE ≥ 6 pixels

XSIZE ≥ 6 pixels

YSIZE ≥ 6 pixels

XMEM_SIZE ≥ 6 pixels

YMEM_SIZE ≥ 6 pixels

YCbCr 4:2:0 Planar XSIZE ≥ 6 pixels

YSIZE ≥ 6 pixels

XSIZE ≥ 6 pixels

YSIZE ≥ 6 pixels

XMEM_SIZE ≥ 6 pixels

YMEM_SIZE ≥ 6 pixels