In the umc_mp4_parser_w.h file i can find a structure with copyright, name and info fields which can have variable lengths. Is there any way to effect the content of these fields? I have tried to change the code to initialize these variables during the Mux->init, and the header including this structure is supposed to be written to the file when i call the mux->Close(). However i cannot see any change to the file using this method. I am basically looking for a way to write some custom information (1-2 strings) as part of the file.