Dct (compression)

EN: Dct (compression)

Fotografie

Short for Discrete Cosine Transform. This is a basic operation of MPEG video compression. It works on blocks -- usually 8 x 8 pixels -- of the picture, turning them into frequencies and amplitudes. DV, WM9, VC9, and JPEG compression also depend on DCT. If data rates are too low, blocks may be visible on the screen.
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