function?[c?s]?=?wavefast（x?n?varargin）
%WAVEFAST?Perform?multi-level?2-dimensional?fast?wavelet?transform.
%???[C?L]?=?WAVEFAST（X?N?LP?HP）?performs?a?2D?N-level?FWT?of
%???image?（or?matrix）?X?with?respect?to?decomposition?filters?LP?and
%???HP.
%
%???[C?L]?=?WAVEFAST（X?N?WNAME）?performs?the?same?operation?but
%???fetches?filters?LP?and?HP?for?wavelet?WNAME?using?WAVEFILTER.
%
%???Scale?parameter?N?must?be?less?than?or?equal?to?log2?of?the
%???maximum?image?dimension.??Filters?LP?and?HP?must?be?even.?To
%???reduce?border?distortion?X?is?symmetrically?extended.?That?is
%???if?X?=?[c1?c2?c3?...?cn]?（in?1D）?then?its?symmetric?extension
%???would?be?[...?c3?c2?c1?c1?c2?c3?...?cn?cn?cn-1?cn-2?...].
%
%???OUTPUTS:
%?????Matrix?C?is?a?coefficient?decomposition?vector:
%
%??????C?=?[?a（n）?h（n）?v（n）?d（n）?h（n-1）?...?v（1）?d（1）?]
%
%?????where?a?h?v?and?d?are?columnwise?vectors?containing
%?????approximation?horizontal?vertical?and?diagonal?coefficient
%?????matrices?respectively.??C?has?3n?+?1?sections?where?n?is?the
%?????number?of?wavelet?decompositions.?
%
%?????Matrix?S?is?an?（n+2）?x?2?bookkeeping?matrix:
%
%??????S?=?[?sa（n?:）;?sd（n?:）;?sd（n-1?:）;?...?;?sd（1?:）;?sx?]
%
%?????where?sa?and?sd?are?approximation?and?detail?size?entries.
%
%???See?also?WAVEBACK?and?WAVEFILTER.

%???Copyright?2002-2004?R.?C.?Gonzalez?R.?E.?Woods?&?S.?L.?Eddins
%???Digital?Image?Processing?Using?MATLAB?Prentice-Hall?2004
%???$Revision:?1.5?$??$Date:?2003/10/13?01:14:17?$

%?Check?the?input?arguments?for?reasonableness.
error（nargchk（3?4?nargin））;

if?nargin?==?3
???if?ischar（varargin{1}）???
??????[lp?hp]?=?wavefilter（varargin{1}?‘d‘）;
???else?
??????error（‘Missing?wavelet?name.‘）;???
???end
else
??????lp?=?varargin{1};?????hp?=?varargin{2};???
end

fl?=?length（lp）;??????sx?=?size（x）;

if?（ndims（x）?~=?2）?|?（min（sx）????error（‘X?must?be?a?real?numeric?matrix.‘）;?????
end
??
if?（ndims（lp）?~=?2）?|?~isreal（lp）?|?~isnumeric（lp）?...
???????|?（ndims（hp）?~=?2）?|?~isreal（hp）?|?~isnumeric（hp）?...
??