Digital Signal Processing Reference
In-Depth Information
Table 13.2
Typical Wavelet Filter Coefficients
h
0
ðkÞ
Haar
Daubechies 4
Daubechies 6
Daubechies 8
0.707106781186548
0.707106781186548
0.482962913144534
0.836516303737808
0.224143868042013
0.332670552950083
0.806891509311093
0.459877502118492
0.230377813308896
0.714846570552915
0.630880767929859
0.129409522551260
0.135011020010255
0.027983769416859
0.085441273882027
0.035226291885710
0.187034811719093
0.030841381835561
0.032883011666885
0.010597401785069
The original scaling function
fðtÞ
is also included as shown in the last plot for comparison.
With the given coefficients
h
0
ðkÞ
and applying Equation
(13.45)
, we can obtain the wavelet
coefficients
h
1
ðkÞ
as
h
1
ð
0
Þ¼
0
:
1294
; h
1
ð
1
Þ¼
0
:
2241
; h
1
ð
2
Þ¼
0
:
8365
;
and
h
1
ð
2
Þ¼
0
:
4830
1
2
0.5
1
0
0
-0.5
-1
0
1
2
3
0
1
2
3
0.5
0.5
0
0
-0.5
-0.5
0
1
2
3
0
1
2
3
2
2
1
1
0
0
-1
-1
0
1
2
3
0
1
2
3
Time (s ec . )
Time (s ec . )
FIGURE 13.33
Constructed 4-tap Daubechies father wavelet.
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