ExifTool Forum

ExifTool => The "exiftool" Application => Topic started by: camner on October 05, 2024, 08:23:20 PM

Title: IFD0 and XMP-XMP ModifyDate tags
Post by: camner on October 05, 2024, 08:23:20 PM
What kinds of changes/modifications to an image file should make the values of the IFD0:ModifyDate and XMP-XMP:ModifyDate tags change value? 
Title: Re: IFD0 and XMP-XMP ModifyDate tags
Post by: Phil Harvey on October 05, 2024, 08:57:21 PM
According to the specifications, this is supposed to be updated whenever the file is written.

- Phil
Title: Re: IFD0 and XMP-XMP ModifyDate tags
Post by: camner on October 12, 2024, 01:16:24 AM
Thanks.  I don't think either Lightroom or Adobe Bridge respect this.  I have made several changes to metadata with either or both of these and these tags are NOT rewritten.
Title: Re: IFD0 and XMP-XMP ModifyDate tags
Post by: StarGeek on October 12, 2024, 11:03:12 AM
They are probably only updating the MetadataDate when the change is only the metadata.

The EXIF standard says under the DateTime entry (which is the actual name of the ModifyDate)
QuoteIn this standard it is the date and time the file was changed.

But later on, under Annex H.4 Category and Rank Relationship, which covers when a tag should be updated, it says
SumatraPDF-2024-10-12_07.52.50.png

Which sounds more like editing of the actual image, at least to me.