640 X 480 is about 300,000 pixels and is not far from 530 X 400 which is about 200,000 pixels.
TV and video are typically 4:3 (standard screen) and 16:9 (widescreen). 1920 x 1080=2 megapixel is a typical widescreen resolution. 768 X 1024=0.75 megapixel is typical for 4:3.