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Frame buffer for 640×480 B/W video

Short answer

Black‑and‑white uses 1 bit/pixel, so one 640×480 frame = 38,400 bytes. At 25 fps, 5 minutes yields 7,500 frames, giving total storage = 288,000,000 bytes ≈ 275 MB.

Calculate the size of frame buffer required to store a 640×480 B and W video of length 5 minutes without compression.

A black-and-white (bi-level) image needs 1 bit per pixel. The video size equals frame size × number of frames. The frame rate is not given, so assume 25 fps.

Pixels per frame = 640 × 480      = 307,200
Bits per frame   = 307,200 × 1    = 307,200 bits
Bytes per frame  = 307,200 / 8    = 38,400 B (37.5 KB)
Time             = 5 × 60         = 300 s
Frames           = 25 × 300       = 7,500
Total size       = 38,400 × 7,500 = 288,000,000 bytes
                                  ≈ 274.7 MB (÷ 2²⁰)

For other frame rates the size scales linearly (at 30 fps: 345,600,000 B ≈ 329.6 MB).

Answer: one frame needs 38,400 bytes; 5 minutes at 25 fps needs 288,000,000 bytes ≈ 275 MB.

✓ Answer checked by Claude Opus 5.5 (high effort)

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