gif to wbmp on the fly conversion

my vb.net program needs to have a function convert2wbmp so i can do this : wbmphexdump = convert2wbmp(gifhexdump) each byte byte is represented by two consecutive hex numbers so GIF (the first three bytes in a gif file) is in hexdump : 474946 the hexdump i am giving is thus looking like this : 47494638396148..... and the hexdump i need in return has to be like that also so the hexdump is in this format 000102030405060708090a0b0c0d0e0f1011121314 etc.... no files may be used, everything has to be done in the computers memory the hexdump is of type STRING the returned(converted) hexdump is also of type STRING ## Deliverables 1) Complete and fully-functional working function / component as well as complete source code of all work done. i'd like to receive an intermediate ( beta ) version of a function/component i can use within my VB.net without having to register any dll's / ocx's ## Platform .NET framework i prefer VB.net, but anything is negotiable