Inserting random bytes in .bin esp32

Hi community…
I am working with esp32 and platformio…
I would like to write some code to insert random characters into the binary (at fixed or maybe even “random” intervals). As long as my ESP32 code can decode/follow/remove those random characters BEFORE passing it to “partitionWrite”,
The scope it is do to a kind of check of the fw before to install it…
Any idea or repo or lib about how to do it ?

Thanks a lot