數(shù)字圖像處理實驗一課件

1、數(shù)字圖像處理實驗一圖像灰度變換及直方圖顯示熟悉matlab的編程環(huán)境；復(fù)習(xí)MATLAB語言的基本用法；掌握MATLAB語言中圖象數(shù)據(jù)與信息的讀取存儲方法；掌握matlab中圖像灰度變換方法；掌握在MATLAB中繪制灰度直方圖的方法； 實驗?zāi)康膶嶒炛羞\用的函數(shù) A=imread(FILENAME.FMT) imshow(A,low high) imwrite(A,FILENAME.FMT) G = intrans(F, neg) G = intrans(F, log, C, CLASS) G = intrans(F, gamma, GAM) G = intrans(F, stretch, M,

2、E)實驗中運用的函數(shù)imhist(I)：displays a histogram for the image I above a grayscale colorbar. imhist(I, n)：displays a histogram where n specifies the number of bins used in the histogramimhist(X, map) ：displays a histogram for the indexed image X.counts,x = imhist(.)： returns the histogram counts in counts a

3、nd the bin locations in x so that stem(x,counts) shows the histogram. 實驗中運用的函數(shù)imhist(f)Bar(horz, v, width) v:一個行向量，包含被繪制的點 horz：與v維數(shù)相同的向量，包含水平標(biāo)度值的增量，若忽略horz， 則horz在0到length（v）之間等分若干 width：0到1之間的數(shù)值。width為1時條狀最明顯，0時為線。Stem(horz, v, color_linestyle_marker, fill) color_linestyle_marker：顏色，線類型，標(biāo)記 fill：若使

4、用fill，標(biāo)記點顏色與corlor一致Plot(horz, v, color, g, linestyle,none,marker,s)實驗內(nèi)容讀出一副圖像，利用灰度變換函數(shù)，基于switch語句分別實現(xiàn)圖像灰度的反變換，對數(shù)變換，對比度拉伸變換，gamma變換操作，利用subplot在一個圖像窗口的不同區(qū)域分別顯示變換的結(jié)果。針對灰度變換后的圖像，采用不同的方法繪制直方圖，分析每種灰度變換后，直方圖之間的區(qū)別。實驗內(nèi)容：操作提示function yourOutput = Yourfunctionname (yourInput)H1 行參數(shù)介紹%讀入圖像利用imadjust實現(xiàn)反變換，及對數(shù)變

5、換，再利用intrans實現(xiàn)gamma變換和對比度拉伸變換。這里要進(jìn)行哪種變換，需要利用switch語句來控制；分別把每種變換結(jié)果利用subplot顯示出來對每種變換的圖像進(jìn)行直方圖計算，并利用不同的方法顯示直方圖實驗內(nèi)容：操作提示function g = intrans(f, varargin)% Verify the correct number of inputs.error(nargchk(2, 4, nargin) % Store the class of the input for use later.classin = class(f); % If the input is of

6、 class double, and it is outside the range0, 1, and the specified transformation is not log, convert the input to the range 0, 1.if strcmp(class(f), double) & max(f(:) 1 & . strcmp(varargin1, log) f = mat2gray(f);else % Convert to double, regardless of class(f). f = im2double(f);end實驗內(nèi)容：操作提示% Determ

7、ine the type of transformation specified.method = varargin1;% Perform the intensity transformation specified. switch methodcase neg g = imcomplement(f); case log if length(varargin) = 1 c = 1; elseif length(varargin) = 2 c = varargin2; elseif length(varargin) = 3 c = varargin2; classin = varargin3;

8、else error(Incorrect number of inputs for the log option.) end g = c*(log(1 + double(f);實驗內(nèi)容：操作提示case gamma if length(varargin) 2 error(Not enough inputs for the gamma option.) end gam = varargin2; g = imadjust(f, , , gam); case stretch if length(varargin) = 1 % Use defaults. m = mean2(f); E = 4.0; elseif length(varargin) = 3 m = varargin2; E = varargin3; else error(Incorrect number of inputs for the stretch option.) end g = 1./(1 + (m./(f +