Let’s pretend that you’ve made a mistake when creating a binary image and you didn’t realize it until after you painstakingly created this image for use in a production process. Well, instead of going back and doing it all over again, you can simply use hexedit to edit the binary file directly, saving you precious time.
hexedit -m binaryfile.dd
In my particular case, I was trying to create an SD card image for use in an SBC product and I didn’t realize until it was too late that there was a type-o in a script. I used hexedit to fix the type-o and everything worked out heavenly.