One-dimensional forward Discrete Cosine Transform is defined by the equation:
where:
f(n) - an original signal sample,
F(k) - a sample of the spectrum,
0 ≤ n, k ≤ N.
This transform may be generalized to a two-dimensional transform defined by the formula:
f(n1,n2) - a sample of an image,
F(k1,k2) - a sample of the two-dimensional spectrum,
0 ≤ n1, k1 ≤ N1, 0 ≤ n2, k2 ≤ N2.
The transform size is mostly set to N1 = N2 = 8.
