Jet Grind Radio Custom Graffiti

[Elixir Alex]

After some research and thorough experimenting I managed to create custom Jet Grind Radio graffiti saves. It's basically a jpeg with a 1-bit transparency channel tacked on. Here's my notes so far:

Code: Select all

640 bytes - VMS Header and VMU Icon
4 bytes - size of title
n bytes - title
4 bytes - size of description
n bytes - description
4 bytes - size of e-mail (optional)
n bytes - e-mail (optional. can be blanked out alongside the size with four empty bytes)
4 bytes - size of transparency data (00 xx xx 00) 0800 = small, 1000 = large, 2000 = extra large
2048/4096/8192 bytes (or $0800, $1000, and $2000) - Transparency data. (0 for transparent, 1 for opaque, need to reverse bits of each byte.)
4 bytes - size of unknown bytes, copyright, and jpeg data as a short. Theoretical max jpeg size would be ~63.99KB
6 bytes - unknown, possibly a portion of the copyright?
36 bytes - SEGA copyright
n bytes - JPEG data (headerless. can't be progressive)

Display of Newgrounds Graffiti Pack

Small Custom Graffiti Example

Large Custom Graffiti Example

Extra Large Custom Graffiti Example

[Sonic1994DC]

Great custom graffiti. Love to see all the custom graffiti people make for this game

[Elixir Alex]

Great custom graffiti. Look to see all the custom graffiti people make for this game

Would be great but all the hex editing is inconvenient. if I knew how to make programs I'd try to make a converter for it if I could.

[OatBob]

Would also be awesome to find some legacy backups of custom graffiti from back-in-the-day. I image all the US stuff was SSJ3 Gojeta or something limited to that period of the internet.