ExifTool Forum

ExifTool => Bug Reports / Feature Requests => Topic started by: xvalen on December 24, 2023, 11:17:12 AM

Title: Weird coordinates offset when setting GPSLongitude in batch from command-line
Post by: xvalen on December 24, 2023, 11:17:12 AM
So I've finally started the project to GPS'ize my old photos to be able to see them on map.
Tested exiftool with couple of folders, all was fine, now I've created a script that would set location for JPG's, but pulling my hair - it sets GPSLongitude with some weird offset, sending location a bit off in most of the cases  .
I've tried to get latest version of ExifTool, tried to switch from decimal to DMS - same issue.

Is it me doing something stupid or there's issue with exiftool on Windows 10? 

Here's what I am doing for example:
exiftool(-Comment='NiagaraFalls' -charset filename=cp1251 -wm cg -P -GPSLatitude='43 4 44.277' -GPSLongitude='-79 4 44.31' -GpsLongitudeRef=W -overwrite_original).exe

And I end up with DMS 43° 4′ 44.27″ N, 78° 55′ 15.68″ W as returned by XnView and other tools.

Surprisingly my usual FastStone viewer does not recognize coordinates set by ExifTool, but it's not a big deal..

Title: Re: Weird coordinates offset when setting GPSLongitude in batch from command-line
Post by: Phil Harvey on December 24, 2023, 12:42:14 PM
Try this:

exiftool(-Comment='NiagaraFalls' -charset filename=cp1251 -wm cg -P -GPSLatitude='43 4 44.277' -GPSLongitude='-79 -4 -44.31' -GpsLongitudeRef=W -overwrite_original).exe

I've added a new to FAQ 14 (https://exiftool.org/faq.html#Q14) to illustrate this.

..but it would be simpler to specify the coordinates in +-DD.DDDDDD format.

- Phil
Title: Re: Weird coordinates offset when setting GPSLongitude in batch from command-line
Post by: xvalen on December 24, 2023, 01:33:49 PM
Thank you very much, this worked!
I've had the same problem with decimal format I believe, that's what made me to convert coordinates to DMS format in the first place.

Overall wasn't easy project, seems to be worth writing a guide / post to share my approach and caveats. And exiftool is the only tool that made it possible with all features supported to make it work🧡 - from setting coordinates, to preserving file_created date and other tags, all in batch

- created txt file with "comment, lat, lon" (the latter two are easy to copy right away from google maps)
- created Python script that would grab each string and create copy of exiftool.exe with generated parameters (ChatGPT to help, I am not a software developer)
- another Python script to temporary convert non-Latin folder names into English symbols only with originals stored in file
- drag and drop entire folders or batches of files(as sometimes you'd have multiple places in one trip/folder) to corresponding executable with right parameters
- run second script to reverse folder name changes
- enjoy

(before enjoy there's copy to Synology photos which I found to be the best to view existing archive on map / timeline, comparing to many opensource solutions like Photoprism or closed source stuff)
Title: Re: Weird coordinates offset when setting GPSLongitude in batch from command-line
Post by: StarGeek on December 24, 2023, 01:35:49 PM
Ah, I see now.  I was testing this trying to figure out what happened.  It was using -79°, then adding 4' and 44.31".

But yeah, digital is simpler.  The GPSPosition you added to make it easy to right-click on Google Maps to get and add the coordinates is great.
Title: Re: Weird coordinates offset when setting GPSLongitude in batch from command-line
Post by: Phil Harvey on December 24, 2023, 03:55:51 PM
Quote from: StarGeek on December 24, 2023, 01:35:49 PMThe GPSPosition you added to make it easy to right-click on Google Maps to get and add the coordinates is great.

Yeah, I like using that one myself.

- Phil