38.6.3.3 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.
| 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.
| 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 |