Преобразуйте подъем схемы к квадруплету фильтров
[LoD,HiD,LoR,HiR] = ls2filt(LS)
[LoD,HiD,LoR,HiR] = ls2filt(LS) возвращает четыре фильтра LoD, HiD, LoR и HiR, сопоставленный с поднимающейся схемой LS.
% Start from the db2 wavelet and get the
% corresponding lifting scheme.
LS = liftwave('db2')
LS =
'd' [ -1.7321] [ 0]
'p' [1x2 double] [ 1]
'd' [ 1] [-1]
[1.9319] [ 0.5176] []
% Visualize the obtained lifting scheme.
displs(LS);
LS = {...
'd' [ -1.73205081] [0]
'p' [ -0.06698730 0.43301270] [1]
'd' [ 1.00000000] [-1]
[ 1.93185165] [ 0.51763809] []
};
% Get the filters from the lifting scheme.
[LoD,HiD,LoR,HiR] = ls2filt(LS)
LoD =
-0.1294 0.2241 0.8365 0.4830
HiD =
-0.4830 0.8365 -0.2241 -0.1294
LoR =
0.4830 0.8365 0.2241 -0.1294
HiR =
-0.1294 -0.2241 0.8365 -0.4830
% Get the db2 filters using wfilters.
% You can check the equality.
[LoDref,HiDref,LoRref,HiRref] = wfilters('db2')
LoDref =
-0.1294 0.2241 0.8365 0.4830
HiDref =
-0.4830 0.8365 -0.2241 -0.1294
LoRref =
0.4830 0.8365 0.2241 -0.1294
HiRref =
-0.1294 -0.2241 0.8365 -0.4830