WHAT ARE FBs?FBs are a console/PSP specific way of storing all the files needed for a character or level. In very loose terms it's sortof like a zip file. All files needed for a particular character or level are stored inside.
IS THERE A FB EDITOR?Yes and no. There's not a way to simply drag and drop files. You must use a hex editor to insert, remove and change files.
FILE STRUCTUREFBs are made up of two parts: the header and the file itself. The header is also broken up into three smaller parts: The file's directory and name, the file type (for in-game use) and the filesize. Together these make up 196 bytes. (BYTES: on the left side of a hex editor that means two digits - on the right side it means one left/right move of the cursor)
The first 128 bytes
(seen in blue) are the filename and folder. Notice this isn't actually a folder, it's just the path of where the file would be. 00's fill up the rest of this section.
The next 64 bytes
(seen in red) is the file type. This is used in-game to specify things. Basically there's no need to edit this. Again, 00's fill up the empty space.
The last four bytes
(seen in yellow) is the file size. This is done in reverse hexidecimal. See 'Editing the Filesize' below for more info.
After the header, the actual file data begins, and continues until the next header is started (as noted by a new folder/filename).
Inserting new filesThe easiest way to do this is to copy the entire entry (from the header to the last byte before the next header) and paste it just before the start of a header in a new file. Sometimes you can't do that though. Say you change ps_gambit.engb. Well, odds are there's one in the FB we're putting it into, so we want to replace that. So we find it by searching for it in the hex editor. Next we go to the end of the header. The next byte after the header is the first byte of the actual file. The last byte of the actual file is the last byte before the next header. So we highlight all of that. Next, open your new ps_gambit.engb in a hex editor and select all. Go back to your FB and paste in the area you've selected. We're nearly done, but we need to do one last thing, fix the filesize.
Editing the filesizeLooking at the example above we see the filesize as 1F 7B 01 00. First thing we do is turn that around to 00 01 7B 1F. Next, we visit
THIS site and input 00017B1F in the left box and hit 'to decimal'. It comes out as 97055. That's how many bytes a file is. So if we were putting a new file in as a replacement for one already there, we'd get the filesize of the file we're replacing by right clicking it and hitting properties. We get the ##### bytes under the Size: section. Then we just reverse the process.