FITC modifies ME firmware with thousands of bytes?

I want to update Intel ME to version on a Ivy Bridge/Intel QM77 Chipset (Panther Point) system. I have downloaded ME firmware from vendor and included that in SPI image, but found out that I need to configure correct ICC Data for the system to work. For this task I’m using Flash Image Tool However, after doing following test there is something that bothers me:

I open SPI image in FITC and without making any modifications I click Build Image. Then I extract flashregion_2_intel_me.bin from outimage.bin created by FITC and binary compare that with flashregion_2_intel_me.bin extracted from original SPI image. Even tough no modifications were done in FITC, the two ME region images now differ with thousands of bytes.

I would really like to understand what modifications FITC is doing to the ME firmware, but this is impossible by just looking at the binary data. Is there any way I can compare the two extracted ME region images and get a clear view of what the changes does?