Tags: forensic 

Rating:

# Solution
If you open the picture in a binary editor, you will see that the structure resembles a jpg file with some changes. After carefully comparing the file header with the jpg header, it becomes clear that each byte is replaced with 0xFF - currentByte.

```
open("secret.jpg", "wb").write(bytes(map( lambda x : (0xFF - x) , list(open("secret.img", "rb").read()))))
```

Done!