ExifTool Forum

ExifTool => The "exiftool" Application => Topic started by: ekkidee on December 05, 2017, 09:53:24 PM

Title: ShutterCount
Post by: ekkidee on December 05, 2017, 09:53:24 PM
I'm trying to use ShutterCount as a way to uniquely identify files in a catalog. This works fine on images from my Nikon, as I am guaranteed a unique number. The NEF files have a -ShutterCount argument that produces a five-digit number.

On my cell phone (LG), it's not as easy. There is apparently no ShutterCount or ImageCount in the EXIF. I have tried using the file's CreationDate time stamp to create a unique ID, and then stuff that into ShutterCount, putting in the form of yymmdd-hhmmss.

That is presenting a whole new set of problems. Using

exiftool -ShutterCount=1 filename

returns

Warning: [minor] Maker notes could not be parsed - filename

I've read a little about parsing maker notes and I can't see anything unusual in the maker notes for the LG files. Can maker notes be stripped out of jpg's without penalty? Can exiftool be made to specify which particular maker note it's choking on?

Thanks for any help.
Title: Re: ShutterCount
Post by: Phil Harvey on December 06, 2017, 07:27:05 AM
ExifTool is just warning you that the maker notes may be corrupted if rewritten.  The file will be rewritten regardless, but the ShutterCount won't be added because there is no EXIF, XMP or IPTC tag by that name, and individual maker note tags may not be added.  I would recommend instead using EXIF:ImageUniqueID.  To write an ImageUniqueID that is guaranteed to be unique, do this:

exiftool "-imageuniqueid<newguid" FILESorDIRS

- Phil
Title: Re: ShutterCount
Post by: ekkidee on December 06, 2017, 08:54:38 AM
Great thank you Phil, and thank you for a wonderful tool.