Làm tròn: H8, W8 chia hết cho 8: H8 = H; If h mod m 0 Then H8 = (H / m + 1) m w8 = H: If w mod m 0 Then W8 = (W / m + 1) m đặt bằng 0 phần mở rộng của ảnh f(I,j): For I = 1 To H8 For j = W+1 To W8 f(I, j) = 0 For j = 1 To W8 For j = H+1 To H8

H8 = H; If H Mod M <> 0 Then H8 = (H / M + 1) * M

W8 = H: If W Mod M <> 0 Then W8 = (W / M + 1) * M

Đặt bằng 0 phần mở rộng của ảnh f(i,j):

For i = 1 To H8

For j = W+1 To W8

f(i, j) = 0

For j = H+1 To H8

where u = 0, 1, ..,7; v = 0, 1, ..,7

au(0) = (1 / M) ^ (1 / 2)

For u = 1 To M - 1: au(u) = (2 / M) ^ (1 / 2): Next
Biến đổi cosine
For u = 0 To (H8 - 1) / M

For v = 0 To (W8 - 1) / M

For p = 0 To M - 1

For q = 0 To M - 1

fcos(u * M + p, v * M + q) = 0

For Y = 0 To M - 1

For X = 0 To M - 1

alphaX = omegaM * (2 * X + 1) * p

alphaY = omegaM * (2 * Y + 1) * q

fc(u * M + p, v * M + q) = fc(u * M + p, v * M + q) + f(u * M + X, v * M + Y) * Cos(alphaX) * Cos(alphaY)

Next X: Next Y

fc(u * M + p, v * M + q) = au(p) * au(q) * fc(u * M + p, v * M + q)

Next q: Next p

Next v: Next u

For j = 0 To (W8 - 1) / M

For X = 0 To M - 1

For Y = 0 To M - 1

dc = 0

For u = 0 To M - 1

alphaX = omegaM * (2 * X + 1) * u

alphaY = omegaM * (2 * Y + 1) * v

dc = dc + au(u) * au(v) * fc(i * M + u, j * M + v) * Cos(alphaX) * Cos(alphaY)

Next v

Next u

Next: Next