Should Copy Attributes - XMP GPS data copy time stamp?

[hluxem]

Quite often I like to copy the GPS data between files using the  Ctrl+C and Shift+Ctrl+V short cuts. I know that I could use location for that, but I just have too many and its not as efficient as copy and paste.
I just realized that when I copy the xmp GPS data the time stamp is copied too. I think that is wrong and makes no sense to me. Not sure if my expectation is simply wrong or if its a bug. I only want to copy the GPS coordinates and the location data between images. Below is what the help says, not sure if the MWG compliance forces the change of the time stamps.

GPS Data
When you want to copy GPS data between files you should normally use the XMP GPS Data set in this dialog. If MWG compliance is enabled, IMatch copies the GPS coordinates from XMP into the corresponding EXIF GPS tags automatically.

Heiner

[Mario]

ExifTool copies GPS data as a block to ensure integrity. IMatch just triggers that (GPS group) when you enable the option. IMatch does not copy individual tags or anything.

[lbo]

Heiner: You can also use the metadata Panel for copy/paste. There you can define a custom panel containing only the tags you want to copy or paste. See "The Toolbar" in https://www.photools.com/help/imatch/#md_panel.htm?dl=h-15

Mario: It might be helpful to extend the help text about this. Currently, it states "When you do a Copy/Paste operation, IMatch does not copy all the metadata between the files. It copies only the metadata tags actually used (visible) in the metadata panel."

From this, it's not 100% clear whether the paste action applies also to the tags visible in in the current panel. E.g. I do the "copy" action with one set of entries, but the "paste" action on a different panel.

As far as I see, only the intersecting set is used, correct?

Oliver

[Mario]

Yes.

Standard Windows clipboard behavior. You can only paste what you have previously copied.

If you find an error, typo or omission on a help page or you want me to extend the text, please use the "Feedback" link available at the bottom of each help page.
This not only tells me which of the hundreds of pages you mean but also puts your request into a queue with other help requests. I work on them in batches every couple of weeks.

[lbo]

You can only paste what you have previously copied.

obviously, but that was not my question.

Never mind, I can verify it by an experiment.

Oliver

[hluxem]

If you find an error, typo or omission on a help page or you want me to extend the text, please use the "Feedback" link available at the bottom of each help page.

Just send feedback to add a table identifying the tags copied.

You can also use the metadata Panel for copy/paste.

Thanks Oliver!
That works. I was hoping I can select and highlight a section of the panel, but I do have to switch to a panel with only the tags I want. Just some extra steps compared to the copy and paste shortcuts, but does exactly what I need.


Last not least, not sure what the new telemetry data says, maybe I'm the only one using the copy function. If not, I like to suggest to change the text in the dialog to "XMP GPS DATA (includes time stamp)". That could prevent other users from unintended changing time stamps on files. No problem for me as my file names are date and time based and I can use a meta data template to easily recover.
With 230K files I have too many places to create locations from, I like to use the copy and paste to copy the locations fields.

Heiner

[Mario]

That could prevent other users from unintended changing time stamps on files.

Copying the GPS timestamp does not affect Created/Digitized/Modified timestamps. Not sure what you mean.
Copying the entire GPS record instead of just one or two coordinates makes a lot more sense, because it ensures integrity of the GPS block on the file.

Creating a table of tags copied is not very useful. The tags in the ExifTool GPS group may change, may depend on the file format or GPS record version etc.
For the technically interested user (and there are only a few), all ExifTool tag groups are documented in the ExifTool documentation, which is the best place of course:

https://sno.phy.queensu.ca/~phil/exiftool/TagNames/GPS.html

[hluxem]

Copying the GPS timestamp does not affect Created/Digitized/Modified timestamps. Not sure what you mean.

That kind of was my question, sure enough I tried it again and it's not happening.

I know that I had the wrong time stamp after doing the copy and paste. The pictures were sorted weirdly and I checked why. The time stamp did certainly not revert when I did a rescan. I can't go back as I fixed the timestamp.

This may be related to this resolved bug.
https://www.photools.com/community/index.php?topic=7973
https://www.photools.com/community/index.php?topic=8129.msg57099#msg57099

I will watch closely and in case I see it again try to get some information. 

The good thing is I can use the copy and paste function safely.

Heiner

[lbo]

Copying the entire GPS record instead of just one or two coordinates makes a lot more sense, because it ensures integrity of the GPS block on the file.

The "GPS" name part of this block is somewhat misleading since many entries are not coming from the global positioning system but manual entry. Or maybe a magnetic compass.

Think about GPSLongitude/Latitude and the related "...Dest..." coordinate. Only one of both will be "GPS" data. You uusually won't have two GPS receivers on the set.

In my case (aerial photography), GPSLongitude/Latitude (the camera position) comes from GPS, but the GPSDest... information is set manually after the flight.

Often I re-use existing information like dest coordinates if I have an old image of the object. IOW if I take a new photo of the Königsplatz I copy dest coordinates (and more) from an old photo instead of setting it again in the maps app.

In this case, the Camera position (and timestamp) should not be altered. Direction and distance should be calculated again.

Being in a tag group is no reason to make so called "GPS" data atomic, this is not a matter of "integrity". It's just geodata.

Oliver

[Mario]

That's just how I have implemented this. I cannot manage maximum complexity on every level and in each and every feature.

ExifTool offers tag groups for copying between files for safety and convenience. For example, copying the entire EXIF, GPS, XMP or legacy IPTC data block.

If you want to copy individual tags between files, IMatch offers additional functions, including features like Metadata Templates (great for this purpose) or a custom Metadata Panel layout which displays all the tags you want to copy/paste.

Please note that in that case you are responsible that all tags which need to be copied are copied and that you do not introduce out-of-sync metadata blocks because some of the tags in the target file don't match the individual tags you have copied. This can get quite complex.

[lbo]

That's just how I have implemented this. I cannot manage maximum complexity on every level and in each and every feature.

ExifTool offers tag groups for copying between files for safety and convenience. For example, copying the entire EXIF, GPS, XMP or legacy IPTC data block.

I just pointed out that the GPS group doesn't need to be considered atomic due to integrity considerations.

If you want to copy individual tags between files, IMatch offers additional functions, including features like Metadata Templates (great for this purpose) or a custom Metadata Panel layout which displays all the tags you want to copy/paste.

"custom Metadata Panel layout" was the solution I offered above.

How can I copy metadata between images using Metadata Templates?

Oliver

[Mario]

Metadata Templates cannot copied between images. Sorry, lost track of thread. Too many things on my mind.

[hluxem]

Copying the GPS timestamp does not affect Created/Digitized/Modified timestamps. Not sure what you mean.

Just as an update, this happened again to me and at least for now it seems I can repeat it.
Some days ago I copied only the XMP GPS data with the copy attributes function, but the time stamp for all images was changed. It actually changed all the time related tags in the files. There is one Sony specific time tag with the original time left in the files.

As I understand that this may be hard or impossible to track down, I did some more tests and attached some files. I attached the log file and one zipped image where the time stamp changed. It's at the end of the log file.
As I was looking at the image time stamps, I decided to create a small test database and check what happens today with a new smaller database and Imatch restarted. Every time I did the copy attributes with XMP GPS data the time stamps were copied too. Then I went back to my main database and a test folder to see if it happens there too.
That was really interesting as for some pictures the time stamp is changed, with other pictures not. Maybe there is some tag in the pictures which makes Exiftool change the time stamp. Going forward and backward I had on incident where the time was not the same as the main time stamp in the source file.
Checking all tags in that file it looks like this tag was copied to all time stamps in the target files: [IFD1]          Modify Date
I attached a zipped copy of this file as well (2012-06-28 18-29-00.zip). Maybe you can just try and see if on your system the time is changed as well when you use copy attributes and paste the XMP GPS data to the file DSC00262.JPG.

Not sure if you want me to create a bug report or can move this thread to the bug reports.

Heiner

[hluxem]

Just realized the attachments were too big.

I uploaded them to Dropbox:

https://www.dropbox.com/s/1fi751qo7kldzxj/Copy%20GPS%20Data.zip?dl=0

Heiner

[Mario]

Some days ago I copied only the XMP GPS data with the copy attributes function, but the time stamp for all images was changed.

When you copy metadata with copy Attributes, IMatch uses ExifTool to copy the metadata from the source file to the target file. This changes the "last modified on disk" timestamp of course, and some of the metadata "modified" timestamps, e.g. EXIF modified, XMP metadata modified, digest timestamps etc. This is normal.

It will not change the timestamp IMatch uses for the "File DateTime", unless the file has no EXIF created/digitized or other usable timestamps, in which case IMatch falls back to using the "last modified" timestamp. See How IMatch uses Date and Time Information

[hluxem]

It will not change the timestamp IMatch uses for the "File DateTime", unless the file has no EXIF created/digitized

That's not what happens here. If you download and look at the files, you will see that the file actually has Exif created and digitized time stamp. And it for sure changed the time stamp Imatch uses for the "File DateTime" here.

Not sure how much more data I can provide or what else to test. As this is all based on Exiftool, I could try to copy the XMP GPS data with the exiftool command processor, but I don't know the commands and don't think I would get different results.

The reason the [IFD1]          Modify Date tag was mentioned is because it looks like that may be the tag used to fill the Imatch "File DateTime" and tags.

Heiner

[Mario]

You can monitor the commands IMatch is sending to ExifTool via the ExifTool Output Panel (View menu > Panels).

Do you copy "XMP GPS Data" or "GPS Data"?
When I use Copy Attributes to copy the "GPS Data" group, IMatch makes ExifTool run this command:


...
-tagsfromfile
D:\data\a\alpha.jpg
-gps:all
D:\data\a\Charlie.jpg


which looks correct. IMatch tells ExifTool to copy all tags in the GPS group from the source file to the target file.
I set the EXIF created/digitized timestamp to a known value before copying the GPS data. The EXIF record and the timestamps remained unchanged, only the GPS record was copied.

If this changes the EXIF created/digitized timestamp for some of your files, each file needs careful analysis, and this is time-consuming. And I have already a dozen time-consuming analysis cases in my to-do list, with users sometimes waiting for weeks for a response...

Probably only Phil can answer why this copying the GPS data sometimes changes the timestamps for some of your files.
It's probably not worth wasting too much time. Clean the metadata of the files with problems, then copy the data again.

[hluxem]

Thanks Mario,

I will try the exif tool command and see what happens. Not sure what's different in the files, so hard to clean up at the moment. I will report back once I figure something out.

Heiner