Generate Image Histogram
This example shows how to generate the histogram of an image using
Histogram block. The model outputs a bar plot that shows the frequency of occurrence for pixels values in the input image.
Read an input image to the MATLAB workspace.
I = imread('cameraman.tif');
Find the maximum intensity value in the input image.
maxI = max(I(:));
Open the simulink model. The model reads the image stored in variable
I from the MATLAB workspace. The
histogram parameter of the
2-D Histogram block is set to the maximum value of the intensity image. The
Bins parameter of the
2-D Histogram block is set to 128 and the histogram is computed for the entire input.
modelname = 'ex_blkhistogram.slx'; open_system(modelname);
The model outputs a time series that specifies the frequency of occurrence of pixels within each bin. Export the histogram values to MATLAB workspace and plot the histogram.
out = sim(modelname); bar(out.hist.data) xlabel('Histogram Bins') ylabel('Frequency')