Partial-Mask SRAM Object File

Hello friends,

i just want to know what kind of bit file format is Partial-Mask SRAM Object File for ALTERA ,is it possible to create .pmsf file or change .sof files into .Pmsf ?!

if any one sugests me detailed information source about bit file formats and creating them or change them to gether i'll appreciate it .

very sincerely yours

Sogol