How to use Hough Transform to properly detect lines

Hi, upon some research, I have figured out that Hough Transformation is the best approach to detect lines. (After edge detection, I have found out that the lines are not perfectly straight and has a lot of bumps, but from what I understand, Hough Transformation will detect them as lines.)

I want to get the line segments of the tapes on the wall below and eventually want to measure the dimensions of them.

Now, I have tried the Hough Transformation for Line Detection code from http://www.mathworks.com/help/images/hough-transform.html and this is the result I get.

As it can be seen, it is only detecting the bottom part of the tape and not the rest. How could I change it so that all the sides of the tape are being detected as lines? (Also, what is the need for rotating in the example above?) I appreciate your help in advance. Thanks.