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Raster display and frame buffer load time

Short answer

Calculating total bits: 800×1000 pixels × 24 bpp = 19,200,000 bits. Dividing by transfer rate 100,000 bits/s gives loading time = 192 seconds.

What do you understand by raster display technology? Suppose a RGB raster system is to be designed using an 8 inch by 10 inch screen with a resolution of 100 pixels per inch in each direction. How long would it take to load this raster system in frame buffer with 24 bits per pixel, if 10⁵ bits can be transferred per second?

Raster display technology

A raster display divides the screen into a rectangular matrix of pixels. The picture is stored as the colour/intensity of every pixel in a memory area called the frame buffer. The display controller reads the frame buffer row by row (scan line by scan line) and the electron beam sweeps across the screen from left to right and top to bottom, lighting each pixel with the stored intensity. After the last line, the beam returns to the top (vertical retrace) and the refresh repeats, usually 60 times per second. It gives good shading and colour, and is used in TVs and monitors.

Numerical

Screen = 8 in × 10 in, 100 pixels/in
Pixels = (8 × 100) × (10 × 100) = 800 × 1000 = 800,000
Bits per pixel = 24
Frame buffer size = 800,000 × 24 = 19,200,000 bits
Transfer rate = 10⁵ bits/s
Time = 19,200,000 / 100,000 = 192 s

Answer: 192 seconds (3 minutes 12 seconds).

✓ Answer checked by Claude Opus 5.5 (high effort)

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