www.gusucode.com > wavelet工具箱matlab源码程序 > wavelet/wavelet/wpdec2.m
function t = wpdec2(x,depth,wname,type_ent,parameter) %WPDEC2 Wavelet packet decomposition 2-D. % T = WPDEC2(X,N,'wname',E,P) returns a wptree object T % corresponding to a wavelet packet decomposition % of the matrix X, at level N, with a % particular wavelet ('wname', see WFILTERS). % E is a character vector containing the type of entropy (see WENTROPY): % E = 'shannon', 'threshold', 'norm', 'log energy', 'sure, 'user' % P is an optional parameter: % 'shannon' or 'log energy' : P is not used % 'threshold' or 'sure' : P is the threshold (0 <= P) % 'norm' : P is a power (1 <= P) % 'user' : P is a character vector containing the name % of an user-defined function. % % T = WPDEC2(X,N,'wname') is equivalent to % T = WPDEC2(X,N,'wname','shannon'). % % NOTE: When X represents an indexed image, then X is an % m-by-n matrix. When X represents a truecolor image, it becomes % an m-by-n-by-3 array which consists of three m-by-n matrices % (representing the red, green, and blue color planes) concatenated % along the third dimension. % For more information on image formats, see the reference pages % of IMAGE and IMFINFO functions. % % See also WAVEINFO, WENTROPY, WPDEC, WPREC, WPREC2. % M. Misiti, Y. Misiti, G. Oppenheim, J.M. Poggi 12-Mar-96. % Last Revision: 20-Dec-2010. % Copyright 1995-2010 The MathWorks, Inc. % Check arguments. nbIn = nargin; if nbIn < 3 error(message('Wavelet:FunctionInput:NotEnough_ArgNum')); elseif nbIn==3 , parameter = 0.0; type_ent = 'shannon'; elseif nbIn==4 , parameter = 0.0; end if strcmpi(type_ent,'user') && ~ischar(parameter) error(message('Wavelet:FunctionArgVal:Invalid_EntNam')); end % Tree Computation (order = 4). t = wptree(4,depth,x,wname,type_ent,parameter);