Add age to photo

[picmail]

Hi, in xnview I am able to add date and time from file properties or from EXIF.
I'd like to add not absolute value of date/time but the difference - age.
This would be very convinient for baby photo if I can add age like "1 year 10 month"
Is there any possibility for this?

[helmut]

Having a variable holding the age is a good idea, but it will be hard to find a simple and intuitive user interface to support this use case:
An age is the difference between two dates. First date would be "Date taken" in the EXIF data of your image. Second date would be the birthday of your baby. A user interface would be needed to enter the date. What do you do if you have several children?

Perhaps it could be done by providing not just placeholders, but simple functions:
When adding a text, there are placeholders for EXIF dates, for example. A "DateDiff" function could be provided which can calculate the difference between two dates. Second you would need a function "Format" for specifying they way your age is output. When adding text, you would need to specify something like "{Format(AddText(ToDate({EXIF:Date taken})-ToDate('01.01.2013'), 'Y years, M months')".

All pretty complicated...

[picmail]

Having a variable holding the age is a good idea, but it will be hard to find a simple and intuitive user interface to support this use case
...
All pretty complicated...

Lets keep things simple.
If I could do this somehow I would be happy.
Now we have no such function at all.
Now for EXIF date we have autotext : <Date [Y-m-d_H-M-S]>
It can be edited by deleting of any symbol
Why not to make similar autotext: <AgeFromDate [Y-m-d_H-M-S]> ?