drawing the bounding box

I am working on "Facial Expression Recognition Using Facial
Characteristic Points and Gini Index" ,In this i have cropped the parts of face manaually such as mouth eye brows,but please tell how to draw bounding box for different facial expression,In what ways the height of mouth and eyebrows differ

Step1. Input the template and the target image.
Step2. Convert the images into gray scale images.
Step3. Find the 2-d convolution of the target and template image.
Step4. Find the mean and variance of the template image.
Step5. Form the search image from the search region of the template size.

I have completed till step 4,please tell how to perform step5

Mycodes

temp_img=imread('face1.bmp');

srv_img=imread('face2.bmp');

C2 = conv2(temp_img,srv_img,'same');

M=mean(temp_img(:));

V = var(double(temp_img(:)));

result=[M V];

please tell how to perform step 5

[Jan]

I suggest to post, what you have tried so far to solve the step 5 and explain the occurring problems. It is always much easier to suggest an improvement than to solve the problem.

[nkumar]

Actually i dont know how to start step 5