With progressive scan there is no necessity in intentional blurring (sometimes referred to as anti-aliasing) of video to reduce interline twitter and eye strain.
Bitmaps can represent natural art media more readily, although they are not resolution-independent, as aliasing or blurring artifacts become an issue when enlarging a bitmap.
Instant capture systems (besides using interpolation algorithms on every image) also commonly use sharpening, anti-aliasing, anti-moire and compression algorithms on every image as well.
In obtaining the second and third images, the main objective is to filter out aliasing noise, so a rotationally symmetrical function may be more appropriate.