jpeg2000 files & sizes

[SarcasticDwarf]

I am looking at a .jp2 file that within explorer shows as being ~350KB. When opened in Photoshop elements it is showing as ~21MB. By selecting save for web and lossless I get 4.3MB. Does a jp2 file just unpack to that size within an appropriate application?

*EDIT** by Off Topic Moderator FoBoT

wrong forum

 

[DisgruntledVirus]

Here you go

 

[SarcasticDwarf]

Originally posted by: DisgruntledVirus
Here you go

Tried google already and am not getting the answers I need. There is a lot of technical information out there but not much that is appropriately applied (and yes, I checked wikipedia).