bin2flash problem

Hi

I am a greenhand.I have used Urtraedit to convert three .bmp files to three .bin files,each of which is 301K.But after I use the command bin2flash

to convert three .bin files to a image.flash,the image.flash is only 752 K,less than the sum of three 903K. By my surprised ,I use the same command to

convert only one .bin file (301K) to a image.flash ,the image.flash is still 752K. So,I want to know the max content of .bin which the command bin2flash can convert is how much .

I think it is possible that the bin2flash command only convert less than 752K .bin file .

Thank you !