This is the code used by the ERO-ONE erotic game for loading and saving character data to png files (known as character cards).
STEGANO_MAGIC_NUMBER: Set of bytes used to indicate where your stored files start (in the case of ERO-ONE it's ERO1)
STEGANO_CHUNK_END: Set of bytes used to indicate where your stored files end (in the case of ERO-ONE it's EROE)
BITS_PER_BYTE: How many least significant bytes we should use, ERO-ONE uses 2
DATA_OFFSET: Don't touch, the data offset functionality isn't done yet.
ERO-ONE's character storage binary data spec:
| Position | Name | Description |
|---|---|---|
| 0x0 - 0x03 | Start marker (ERO1) | Marks where the character file starts |
| 0x4 | File version | Character file format version (currently 1) |
| 0x5-0x8 | Length of the uncompressed data information | Contains the size in bytes of the json file before being compressed (it's a 32 bit integer) |
| 0x9 - ? | Compressed data | Contains the compressed json file |
| ? - ? | Ending marker (EROE) | Marks the end of the file |