gusucode.com > vision工具箱matlab源码程序 > vision/+vision/en/IDCT.m
classdef IDCT< dsp.DCT %IDCT 2-D inverse discrete cosine transform % HIDCT = vision.IDCT returns a System object, HIDCT, used to compute % the two-dimensional inverse discrete cosine transform (2-D IDCT) of a % real input signal. The number of rows and columns of the input matrix % must be a power of 2. % % HIDCT = vision.IDCT('PropertyName', PropertyValue, ...) returns a 2-D % inverse discrete cosine transform System object, HIDCT, with each % specified property set to the specified value. % % Step method syntax: % % Y = step(HIDCT, X) computes the 2-D inverse discrete cosine % transform, Y, of input X. % % System objects may be called directly like a function instead of using % the step method. For example, y = step(obj, x) and y = obj(x) are % equivalent. % % IDCT methods: % % step - See above description for use of this method % release - Allow property value and input characteristics changes % clone - Create 2-D inverse discrete cosine transform object with % same property values % isLocked - Locked status (logical) % % IDCT properties: % % SineComputation - Method to compute sines and cosines % % This System object supports fixed-point operations. For more % information, type vision.IDCT.helpFixedPoint. % % % EXAMPLE: Use 2-D DCT to analyze the energy content in an image. Set % % the DCT coefficients lower than a threshold to 0 and reconstruct the % % image using 2-D IDCT. % hdct = vision.DCT; % I = double(imread('cameraman.tif')); % J = step(hdct, I); % imshow(log(abs(J)),[]), colormap(jet(64)), colorbar % % hidct = vision.IDCT; % J(abs(J) < 10) = 0; % It = step(hidct, J); % figure, imshow(I, [0 255]), title('Original image') % figure, imshow(It,[0 255]), title('Reconstructed image') % % See also vision.DCT. % Copyright 1995-2016 The MathWorks, Inc. methods function out=IDCT %IDCT 2-D inverse discrete cosine transform % HIDCT = vision.IDCT returns a System object, HIDCT, used to compute % the two-dimensional inverse discrete cosine transform (2-D IDCT) of a % real input signal. The number of rows and columns of the input matrix % must be a power of 2. % % HIDCT = vision.IDCT('PropertyName', PropertyValue, ...) returns a 2-D % inverse discrete cosine transform System object, HIDCT, with each % specified property set to the specified value. % % Step method syntax: % % Y = step(HIDCT, X) computes the 2-D inverse discrete cosine % transform, Y, of input X. % % System objects may be called directly like a function instead of using % the step method. For example, y = step(obj, x) and y = obj(x) are % equivalent. % % IDCT methods: % % step - See above description for use of this method % release - Allow property value and input characteristics changes % clone - Create 2-D inverse discrete cosine transform object with % same property values % isLocked - Locked status (logical) % % IDCT properties: % % SineComputation - Method to compute sines and cosines % % This System object supports fixed-point operations. For more % information, type vision.IDCT.helpFixedPoint. % % % EXAMPLE: Use 2-D DCT to analyze the energy content in an image. Set % % the DCT coefficients lower than a threshold to 0 and reconstruct the % % image using 2-D IDCT. % hdct = vision.DCT; % I = double(imread('cameraman.tif')); % J = step(hdct, I); % imshow(log(abs(J)),[]), colormap(jet(64)), colorbar % % hidct = vision.IDCT; % J(abs(J) < 10) = 0; % It = step(hidct, J); % figure, imshow(I, [0 255]), title('Original image') % figure, imshow(It,[0 255]), title('Reconstructed image') % % See also vision.DCT. end end methods (Abstract) end end