Progressive and Interlaced video
Progressive and Interlaced video
Progressive (p) video: Used by computers and some media players, is to output full-frame images displaying whole frames as single images, one after the other.
Interlaced images (i): used by TV broadcasters. Frames are made by blending elements from two adjacent frames one after the other, splicing odd and even lines together to form each frame.
When a TV processes interlaced video it separates the lines from the adjacent frames and blends them together in the correct sequence to display the progressive video you’re used to watching. This process is called deinterlacing.
Hi Josh, sorry – I should have got onto this earlier. Strictly speaking, interlaced footage consists of two interleaved fields – each field represents alternating lines (as you have mentioned). In essence, this gives us the appearance of smoother high-frame rate footage, though it is, of course, lower resolution than true progressive high frame rate. Deinterlacing is when you either re-render interlaced footage with one field removed (evidently reducing the perceived resolution) or blending both fields together.
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