is it possible for a layman like me to edit the photos of the drivers?
It is possible, and I would encourage you to try and learn by doing.
You need:
1) A program to edit images that can handle TGA files. I recommend Paint.NET.
2) A tool to convert TGA files to GPI, the format GP4 uses. You can use GPIBrowser. An alternative is Slimtex, part of the ZAZ Tools. You will find more information in
Hires GPI Tips, chapter
GPI creating programs.
Process:
With the image editor create images of the size 256x256 px and convert them to the TGA format.
Create the GPI from the TGA files using the tool.
GPI files are stored in subfolder "MenuData\PC\GP2001\Images" of Grand Prix 4. The correlation between the drivers and the GPI numbers is:
driver gpi: 33, 55-56, 60-64, 66, 68, 70, 72, 74-75, 193, 268-273, 304
driver01 = 33
driver02 = 61
driver03 = 193
driver04 = 63
driver05 = 72
driver06 = 272
driver07 = 66
driver08 = 62
driver09 = 55
driver10 = 56
driver11 = 60
driver12 = 74
driver13 = 75
driver14 = 270
driver15 = 68
driver16 = 273
driver17 = 70
driver18 = 64
driver19 = 269
driver20 = 268
driver21 = 304
driver22 = 271
petrus' gpaedia files