CRC FFMPEG issue

[Deepu joy]

Hi , 

I am using STM32L072 of 192Kb series controller. For our project we need FOTA and we are stuck at CRC calculation. As of my knowledge ST needs FFMPEG format for CRC. How to read FFMPEG format of a binary file ? Currently we are using JFLASH tool to calculate CRC. But for ST it is not working.