Explain two raster systems 640 x 480 and 1280x1024

Question

Consider two raster systems with the resolutions of 640 x 480 and 1280 x 1024.

a) How many pixels could be accessed per second in each of these systems by a display controller that refreshes the screen at a rate of 60 frames per second?

b) How much storage (in bytes) is required for each system if 24 bits per pixel are to be stored?

Answer 1

a)Since 60 frames are refreshed per second and each frame consists of 640 x 480 pixels, the access rate of such a system is (640 x 480) * 60 = 1.8432 x 107 pixels/second.

Likewise, for the 1280 x 1024 system, the access rate is (1280 x 1024) * 60 = 7.86432 x 107pixels/second.

b) According to the definition of access rate, we know that the access time per pixel should be 1/ (access rate). Therefore, the access time is around 54 nanoseconds/pixel for the 640 x 480 system, and the access time is around 12.7 nanoseconds/pixel for the 1280×1024 system.