| [iahadamardmatrix] [Up] [iaidct] | Image Transformation |
>>> import Numeric
>>> f = iaread('cameraman.pgm')
>>> iashow(f)
(256, 256) Min= 0 Max= 251 Mean=137.066 Std=87.20
>>> F = iahwt(f)
>>> iashow(Numeric.log(abs(F)+1))
(256, 256) Min= 0.0 Max= 10.4656680176 Mean=1.715 Std=1.31
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| f | Numeric.log(abs(F)+1) |
def iahwt(f):
from Numeric import asarray, Float64, NewAxis, matrixmultiply, transpose
f = asarray(f).astype(Float64)
if len(f.shape) == 1: f = f[:,NewAxis]
(m, n) = f.shape
A = iahaarmatrix(m)
if A==-1: return -1
if (n == 1):
F = matrixmultiply(A, f)
else:
B = iahaarmatrix(n)
if B==-1: return -1
F = matrixmultiply(matrixmultiply(A, f), transpose(B))
return F
| [iahadamardmatrix] [Up] [iaidct] |  |