Exercises
Load an image with interesting textures. Smooth the image in several ways using
cvSmooth()withsmoothtype=CV_GAUSSIAN.Use a symmetric 3-by-3, 5-by-5, 9-by-9 and 11-by-11 smoothing window size and display the results.
Are the output results nearly the same by smoothing the image twice with a 5-by-5 Gaussian filter as when you smooth once with two 11-by-11 filters? Why or why not?
Display the filter, creating a 100-by-100 single-channel image. Clear it and set the center pixel equal to 255.
Smooth this image with a 5-by-5 Gaussian filter and display the results. What did you find?
Do this again but now with a 9-by-9 Gaussian filter.
What does it look like if you start over and smooth the image twice with the 5-by-5 filter? Compare this with the 9-by-9 results. Are they nearly the same? Why or why not?
Load an interesting image. Again, blur it with
cvSmooth()using a Gaussian filter.Set
param1=param2=9. Try several settings ofparam3(e.g., 1, 4, and 6). Display the results.This time, set
param1=param2=0before settingparam3to 1, 4, and 6. Display the results. Are they different? Why?Again use
param1=param2=0but now setparam3=1andparam4=9. Smooth the picture and display the results.Repeat part c but with
param3=9andparam4=1. Display the results.Now smooth the image once with the settings of part c and once with the settings of part d. Display the results.
Compare the results in part e with smoothings that use
param3=param4=9andparam3=param4=0(i.e., a 9-by-9 filter). ...