Picture Resolution

When I open certain jpeg files with folderitem.openasvectorpicture, I get Horizontal and Vertical resolution as 0 in Windows, but 72 in MacOS. I am using Xojo Version 2017 Release 2.1
So now I check the resolution to see if it is 0 and then change it to 72.
Am I missing out on something ?

72 is the default value for macOS.
For Windows 0 probably just indicates that it’s not known.

OK. Thanks