sir,i need to draw the horizontal and vertical histogram of a binary image..plz help?

sir,i need to draw the horizontal and vertical histogram of a binary image..plz help?

[Geoff Hayes]

aejaz - start by looking at imhist (if you have the Image Processing Toolbox) or hist or histogram depending on your version of MATLAB.

Also, please stop copying and pasting your question title into the body of your question and as tags to your question. There is no benefit to doing so.

Answer 1

[Image Analyst]

I don't even know what that is . Do you mean that you want the bar chart of the counts to go vertically or horizontally across the screen??? Do you mean that you want the histogram of one or more specified rows or columns instead of the entire image? Please clarify. And, anyway, since a binary image has only two values, true and false, you can simply get the counts like this

numWhitePixels = sum(binaryImage(:));
numBlackPixels = numel(binaryImage) - numWhitePixels;

If you want a certain sub-image of the binary image, then use this instead of binaryImage

binaryImage(row1:row2, col1:col2);

[aejaz khan]

sir,i need the black intensity of each row along one side and each col along other side for a given black and white image.the image looks like

[Image Analyst]

Specify a row, say row #42. Then to get the intensity along the row (both black and white and anything in between), do this

thisRow = grayImage(42, :); % Extract all columns of row 42.

To get column 18, do this:

thisColumn = grayImage(:, 18); % Extract all rows of column 18.

[aejaz khan]

thanx a lot sir.. It is really working for a particular row or column, but, on a single graph, i need to plot variation of black intensity of each row for the image. It should look like following graph:

The 0,1,2,3... along x axis indicate columns and the multicolored plots along y axis represent black level intensity for each column. The graph should be like that for an image. How to draw for a given image? Help me out.

...help me sir.

[Image Analyst]

[rows, columns] = size(grayImage);
for row = 1 : rows
    rowMeans(row) = mean(grayImage(row,:));
end
bar(rowMeans); % Plot gray level means

[aejaz khan]

thanking you a lot sir...i will definitely remember u in my prayers.