Diffusion Computational physics (master) Browse

compressor.m
e267232796a2master

compressor.m
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			classdef compressor
			properties
			sing
			U
			V
			chnb
			image % constant
			end
			methods
			% img = input image
			% chnb = number of channels (red, green, blue, alpha, bw, ecc...)
			function obj = compressor(img, chnb)
			obj.sing = cell(chnb,1);
			obj.U = cell(chnb,1);
			obj.V = cell(chnb,1);
			obj.chnb = chnb;

			for k = 1:chnb
			[u, D, v] = svd(double(img(:,:,k)));
			obj.sing{k} = diag(D);
			obj.U{k} = u;
			obj.V{k} = v;
			end

			obj.image = img;
			end

			function out = m(obj)
			[out,~] = size(obj.U{1});
			end

			function out = n(obj)
			[out,~] = size(obj.V{1});
			end

			function v = econ_V(obj, N)
			v = cell(obj.chnb,1);
			for k = 1:obj.chnb
			v{k} = obj.V{k}(1:obj.n(), N);
			end
			end

			function u = econ_U(obj, N)
			u = cell(obj.chnb,1);
			for k = 1:obj.chnb
			u{k} = obj.U{k}(1:obj.m(), N);
			end
			end

			function s = econ_singular(obj, N)
			s = cell(obj.chnb,1);
			for k = 1:obj.chnb
			s{k} = obj.sing{k}(1:N);
			end
			end

			function compimg = compress(obj,N)

			compimg = zeros(obj.m(), obj.n(), obj.chnb);

			for k = 1:obj.chnb
			sigma = zeros(obj.m(),obj.n());
			sigma(1:N,1:N) = diag(obj.sing{k}(1:N));
			compimg(:,:,k) = obj.U{k} * sigma * obj.V{k}';
			end

			compimg = uint8(compimg);
			end
			end
			end

			%function [compimg, singval, U, V] = compress(img, N)

			% %cell struct: sing{color_channel, object}
			% %color channel is in {red, green, blue}
			% %object is in {sing, U, V}
			%sing = cell(3,3);

			%for k = 1:3
			% [U, D, V] = svd(double(img(:,:,k)));
			% sing{k,1} = diag(D);
			% sing{k,2} = U;
			% sing{k,3} = V;
			%end
			%
			%M = length(sing{1,2});
			%oldN = length(sing{1,3});
			%compimg = zeros(M, oldN, 3);
			%
			%singval = zeros(N, 3);
			%U = zeros(M, N, 3);
			%V = zeros(N, N, 3);
			%
			%for k = 1:3
			% sigma = zeros(M,oldN);
			% sigma(1:N,1:N) = diag(sing{k,1}(1:N));
			% singval(:,k) = sing{k,1}(1:N);
			% U(:,:,k) = sing{k,2}(:, 1:N);
			% V(:,:,k) = sing{k,3}(:, 1:N);
			% %compimg(:,:,k) = sing{k,2} * sigma * sing{k,3}';
			% comping(:,:,k) = (U(:,:,k) * sigma(1:N,:)) * V(:,:,k)';
			%end
			%
			%compimg = uint8(compimg);
			%end
			%

compphys/exo4/compressor.me267232796a2master

compressor.mView Options

compphys/exo4/compressor.m
e267232796a2master

compressor.m
View Options