parse_inputs.m

实现图像的对数极坐标变换

function [A,Ar,Ac,Nrho,Ntheta,Method,Center,Shape,Class] = parse_inputs(varargin)
% Outputs: A the input image
% Nrho the desired number of rows of transformed image
% Ntheta the desired number of columns of transformed image
% Method interpolation method (nearest,bilinear,bicubic)
% Center origin of input image
% Shape output size (full,valid)
% Class storage class of A

error(nargchk(3,6,nargin));

A = varargin{1};

Ar = size(A,1); % Ar = number of rows of the input image
Ac = size(A,2); % Ac = number of columns of the input image

Nrho = varargin{2};
Ntheta = varargin{3};
Class = class(A);

if nargin < 4
Method = '';
else
Method = varargin{4};
end
if isempty(Method)
Method = 'nearest';
end
Method = lower(Method);
if ~any(strcmp(Method,{'nearest','bilinear','bicubic'}))
error('Method must be one of ''nearest'', ''bilinear'', or ''bicubic''.');
end

if nargin < 5
Center = [];
else
Center = varargin{5};
end
if isempty(Center)
Center = [(Ac+1)/2 (Ar+1)/2];
end
if length(Center(:))~=2
error('Center should be 1x2 array.');
end
if any(Center(:)>[Ac;Ar] | Center(:)<1) % THIS LINE USED TO READ 'if any(Center(:)>[Ar;Ac] | Center(:)<1)' but Ar and Ac should be swapped round -- look at line 40 for whty this should be. A.I.Wilmer, 12th Oct 2002
num2str(['Center is ',num2str(Center(1)),',',num2str(Center(2)) ' with size of image = ',num2str(Ar),'x',num2str(Ac),' (rows,columns)'])
warning('Center supplied is not within image boundaries.');
end

if nargin < 6
Shape = '';
else
Shape = varargin{6};
end
if isempty(Shape)
Shape = 'valid';
end
Shape = lower(Shape);
if ~any(strcmp(Shape,{'full','valid'}))
error('Shape must be one of ''full'' or ''valid''.');
end

if isa(A, 'uint8'), % Convert A to Double grayscale for interpolation
if islogical(A)
A = double(A);
else
A = double(A)/255;
end
end