mbanndlet_tooa.rar_bandlet transform_bandlet变换

function M = load_image(type, n, options) % load_image - load benchmark images. % % M = load_image(name, n, options); % % name can be: % Synthetic images: % 'chessboard1', 'chessboard', 'square', 'disk', 'quaterdisk', '3contours', 'line', % 'line_vertical', 'line_horizontal', 'line_diagonal', 'line_circle', % 'parabola', 'sin', 'phantom', 'circ_oscil', % 'fnoise' (1/f^alpha noise). % Natural images: % 'boat', 'lena', 'goldhill', 'mandrill', 'maurice', 'polygons_blurred', or your own. % % Copyright (c) 2004 Gabriel Peyr? if nargin<2 n = 512; end options.null = 0; type = lower(type); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % parameters for geometric objects eta = 0.1; % translation gamma = 1/sqrt(2); % slope if isfield( options, 'eta' ) eta = options.eta; end if isfield( options, 'gamma' ) eta = options.gamma; end if isfield( options, 'radius' ) radius = options.radius; end if isfield( options, 'center' ) center = options.center; end if isfield( options, 'center1' ) center1 = options.center1; end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % for the line, can be vertical / horizontal / diagonal / any if strcmp(type, 'line_vertical') eta = 0.5; % translation gamma = 0; % slope elseif strcmp(type, 'line_horizontal') eta = 0.5; % translation gamma = Inf; % slope elseif strcmp(type, 'line_diagonal') eta = 0; % translation gamma = 1; % slope end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % for some blurring sigma = 0; if isfield(options, 'sigma') sigma = options.sigma; end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% switch type case 'chessboard1' x = -1:2/(n-1):1; [Y,X] = meshgrid(x,x); M = (2*(Y>=0)-1).*(2*(X>=0)-1); case 'chessboard' if ~isfield( options, 'width' ) width = round(n/16); else width = options.width; end [Y,X] = meshgrid(0:n-1,0:n-1); M = mod( floor(X/width)+floor(Y/width), 2 ) == 0; case 'square' if ~isfield( options, 'radius' ) radius = 0.6; end x = -1:2/(n-1):1; [Y,X] = meshgrid(x,x); M = max( abs(X),abs(Y) )<radius; case 'square_texture' M = load_image('square',n); M = rescale(M); % make a texture patch x = linspace(0,1,n); [Y,X] = meshgrid(x,x); theta = pi/3; x = cos(theta)*X + sin(theta)*Y; c = [0.3,0.4]; r = 0.2; I = find( (X-c(1)).^2 + (Y-c(2)).^2 < r^2 ); eta = 3/n; lambda = 0.3; M(I) = M(I) + lambda * sin( x(I) * 2*pi / eta ); case 'oscillatory_texture' x = linspace(0,1,n); [Y,X] = meshgrid(x,x); theta = pi/3; x = cos(theta)*X + sin(theta)*Y; c = [0.3,0.4]; r = 0.2; I = find( (X-c(1)).^2 + (Y-c(2)).^2 < r^2 ); eta = 3/n; lambda = 0.3; M = sin( x * 2*pi / eta ); case {'line', 'line_vertical', 'line_horizontal', 'line_diagonal'} x = 0:1/(n-1):1; [Y,X] = meshgrid(x,x); if gamma~=Inf M = (X-eta) - gamma*Y < 0; else M = (Y-eta) < 0; end case 'grating' x = linspace(-1,1,n); [Y,X] = meshgrid(x,x); if isfield(options, 'theta') theta = options.theta; else theta = 0.2; end if isfield(options, 'freq') freq = options.freq; else freq = 0.2; end X = cos(theta)*X + sin(theta)*Y; M = sin(2*pi*X/freq); case 'disk' if ~isfield( options, 'radius' ) radius = 0.35; end if ~isfield( options, 'center' ) center = [0.5, 0.5]; % center of the circle end x = 0:1/(n-1):1; [Y,X] = meshgrid(x,x); M = (X-center(1)).^2 + (Y-center(2)).^2 < radius^2; case 'quarterdisk' if ~isfield( options, 'radius' ) radius = 0.95; end if ~isfield( options, 'center' ) center = -[0.1, 0.1]; % center of the circle end x = 0:1/(n-1):1; [Y,X] = meshgrid(x,x); M = (X-center(1)).^2 + (Y-center(2)).^2 < radius^2; case 'fading_contour' if ~isfield( options, 'radius' ) radius = 0.95; end if ~isfield( options, 'center' ) center = -[0.1, 0.1]; % center of the circle end x = 0:1/(n-1):1; [Y,X] = meshgrid(x,x); M = (X-center(1)).^2 + (Y-center(2)).^2 < radius^2; theta = 2/pi*atan2(Y,X); h = 0.5; M = exp(-(1-theta).^2/h^2).*M; case '3contours' radius = 1.3; center = [-1, 1]; radius1 = 0.8; center1 = [0, 0]; x = 0:1/(n-1):1; [Y,X] = meshgrid(x,x); f1 = (X-center(1)).^2 + (Y-center(2)).^2 < radius^2; f2 = (X-center1(1)).^2 + (Y-center1(2)).^2 < radius1^2; M = f1 + 0.5*f2.*(1-f1); case 'line_circle' gamma = 1/sqrt(2); x = linspace(-1,1,n); [Y,X] = meshgrid(x,x); M1 = double( X>gamma*Y+0.25 ); M2 = X.^2 + Y.^2 < 0.6^2; M = 20 + max(0.5*M1,M2) * 216; case 'fnoise' % generate an image M whose Fourier spectrum amplitude is % |M^(omega)| = 1/f^{omega} if isfield(options, 'alpha') alpha = options.alpha; else alpha = 1; end M = gen_noisy_image(n,alpha); case 'gaussiannoise' % generate an image of filtered noise with gaussian if isfield(options, 'sigma') sigma = options.sigma; else sigma = 10; end M = randn(n); m = 51; h = build_gaussian_filter([m m],sigma/(4*n),[n n]); M = perform_convolution(M,h); return; case {'bwhorizontal','bwvertical','bwcircle'} [Y,X] = meshgrid(0:n-1,0:n-1); if strcmp(type, 'bwhorizontal') d = X; elseif strcmp(type, 'bwvertical') d = Y; elseif strcmp(type, 'bwcircle') d = sqrt( (X-(n-1)/2).^2 + (Y-(n-1)/2).^2 ); end if isfield(options, 'stripe_width') stripe_width = options.stripe_width; else stripe_width = 5; end if isfield(options, 'black_prop') black_prop = options.black_prop; else black_prop = 0.5; end M = double( mod( d/(2*stripe_width),1 )>=black_prop ); case 'parabola' % curvature if isfield(options, 'c') c = options.c; else c = 0.1; end % angle if isfield(options, 'theta'); theta = options.theta; else theta = pi/sqrt(2); end x = -0.5:1/(n-1):0.5; [Y,X] = meshgrid(x,x); Xs = X*cos(theta) + Y*sin(theta); Y =-X*sin(theta) + Y*cos(theta); X = Xs; M = Y>c*X.^2; case 'sin' [Y,X] = meshgrid(-1:2/(n-1):1, -1:2/(n-1):1); M = Y >= 0.6*cos(pi*X); M = double(M); case 'circ_oscil' x = linspace(-1,1,n); [Y,X] = meshgrid(x,x); R = sqrt(X.^2+Y.^2); M = cos(R.^3*50); case 'phantom' M = phantom(n);