Datasheet

986
SAM9G15 [DATASHEET]
11052D–ATARM–31-Oct-12
44.6.11.5Color Keying
Color keying involves a method of bit-block image transfer (Blit). This entails blitting one image onto another where not all
the pixels are copied. Blitting usually involves two bitmaps, a source bitmap and a destination bitmap. A raster operation
(ROP) is performed to define whether the iterated color or the overlay color is to be visible or not.
Source Color Keying
If the masked overlay color matches the color key then the iterated color is selected. Source Color Keying is activated
using the following configuration.
z Select the Overlay to Blit
z Set DSTKEY field to zero
z Activate Color Keying setting CRKEY field to 1
z Program Color Key writing RKEY, GKEY and BKEY fields
z Program Color Mask writing RKEY, GKEY and BKEY fields
When the Mask register is set to zero, the comparison is disabled and the raster operation is activated.
Destination Color Keying
If the iterated masked color matches the color key then the overlay color is selected. Destination Color Keying is
activated using the following configuration:
z Select the Overlay to Blit
z Set DSTKEY field to one
z Activate Color Keying setting CRKEY field to 1
z Program Color Key writing RKEY, GKEY and BKEY fields
z Program Color Mask writing RKEY, GKEY and BKEY fields
When the Mask register is set to zero, the comparison is disabled and the raster operation is activated.
44.6.12 LCD Overall Performance
44.6.12.1Color Lookup Table (CLUT)
Table 44-48. CLUT Pixel Performance
CLUT Mode Pixels/Cycle ROTATION SCALING
1 bpp 32 Not supported Supported
2 bpp 16 Not supported Supported
4bpp 8 Not supported Supported
8 bpp 4 Not supported Supported