Setting Dates and Timezone offsets on files with varying sources

[grasdk]

Hi

I'm trying to set these two XMP timestamp tags on mp4 and mov files, from the available info in the files. If I am not mistaken, the principles apply to images as well, though the metadata on images are typically better and more complete than on videos.

Desired value is highlighted
[XMP:XMP-photoshop:Time] Date Created: UTC Timestamp with Z appended
[XMP:XMP-exif:Time] Date/Time Original: Local Timestamp + offset

I have the following sources with available info highlighted:

• Google Pixel phones: [QuickTime:Time] Create Date and Filename both UTC time. [QuickTime:UserData:Location] GPS Coordinates
• Apple iPhones and iPads: [QuickTime:Time] Create Date UTC Time and [QuickTime:Keys:Time] Creation Date local time with offset
• Oneplus phones: [QuickTime:Time] Create Date UTC Time and Filename local time without offset
• Downloaded mp4/mov: Filename local time without offset

Filenames can have different formats, but all the kind that exiftool parses... For example PXL_YYYYMMDD_hhmmss, IMG_YYYYMMDDhhmmss or even just YYYY-MM-DD-hh-mm-ss).

For source 1-3 there is enough info present. I have GPS (in one case), UTC time and/or localtime and from that I can calculate an offset. For source 4 I would have to resort to some assumption about offset.

I have pieced together these commands per source (only an idea for the fourth for now):

• exiftool -config TimezoneLookUp.config' -ee '-XMP:DateCreated<${QuickTime:Createdate}Z' -XMP:DateTimeOriginal<${QuickTime:Createdate;my $offset=$self->GetValue("GoogleLookUpTimeZone");ShiftTime($offset)}+$GoogleLookUpTimeZone' -@ videofiles.txt
  (utilizing an adapted config from StarGeek for looking up timezones with Google API from this post
• exiftool -ee '-XMP:DateCreated<${QuickTime:Createdate}Z' '-XMP:DateTimeOriginal<${QuickTime:CreationDate}' -@ videofiles.txt
• exiftool -ee '-XMP:DateCreated<${QuickTime:Createdate}Z' '-XMP:DateTimeOriginal<${Filename;s/.*(\d{4}).*(\d\d).*(\d\d).*(\d\d).*(\d\d).*(\d\d).*/$1:$2:$3 $4:$5:$6/;$_.=TimeZoneString(int((GetUnixTime($_)-GetUnixTime($self->GetValue("CreateDate")))/1800+0.5)*30)}' -@ videofiles.txt Adapted from this post
• Haven't finished this yet, but since these are typically event pictures shared on social media, I'm satisfied in assuming that they're from my local timezone. My idea is to create a new Tag "HomeTimeZone" with the config file from 1, which only requires a filename with date embedded and has fixed GPS Coordinates for Google. Then use the value to set offset and calculate UTC time using the offset and the ShiftTime funciton. Any other suggestions?

Any comments and improvements on the above are welcome. But here comes the real questions:

The sources above will change over time, some new scenarios will show up. For example a pixel phone photo with gps disabled (oops, there is a problem already with the command). So I want to combine these commands and more into a robust single command that uses the best data available. Something in the lines of (just setting DateTimeOriginal for simplicity):

$ exiftool -config TimezoneLookUp.config -ee '-XMP:DateTimeOriginal<${Filename;s/.*(\d{4}).*(\d\d).*(\d\d).*(\d\d).*(\d\d).*(\d\d).*/$1:$2:$3 $4:$5:$6/;$_.=TimeZoneString(int((GetUnixTime($_)-GetUnixTime($self->GetValue("CreateDate")))/1800+0.5)*30)}' '-XMP:DateTimeOriginal<${QuickTime:CreationDate}' '-XMP:DateCreated<${QuickTime:Createdate;my $offset=$self->GetValue("GoogleLookUpTimeZone");ShiftTime($offset)}+$GoogleLookUpTimeZone' -@ videofiles.txt

I'm trying to leverage that the last assignment that is with a defined value is the highest priority, so I can set the timestamp from any of the sources (and add more, e.g. when only local timestamp is available) in a prioritized  manner.

With the few tests I've tried it seems to use the priority correctly, but when used on the different source files I get warnings:

Source 1:

Code Select Expand

Warning: Day '70' out of range 1..31 for 'Filename' - PXL3_20240812_170019137.mp4
Warning: [minor] Tag 'QuickTime:CreationDate' not defined - PXL3_20240812_170019137.mp4
Source 2:

Code Select Expand

Warning: Use of uninitialized value in subtraction (-) for 'Filename' - IMG_0105.MOV
Warning: Use of uninitialized value $shift in concatenation (.) or string for 'QuickTime:Createdate' - IMG_0105.MOV
Source 3

Code Select Expand

Warning: [minor] Tag 'QuickTime:CreationDate' not defined - oneplus_20240813_103754.mp4
Warning: Use of uninitialized value $shift in concatenation (.) or string for 'QuickTime:Createdate' - oneplus_20240813_103754.mp4
The first warning for source 1, is something about my matchers and the extended file-name timestamp with subsecs included. I could probably add group of 0-3 integers or something for that... but how do I get rid of the "initialized shift value" error on source 2 and 3 (because google timestamp is not defined in the absence of gps coords) and the file name error on source 2 (because filenames are not a date) and the 'the tag not defined 'error on source 1 and 3? (because spurce 3 has no tag). Or can I safely ignore them?

Thanks for reading and commenting.

PS: When you do things like exiftool -alldates<filename some internal parsing of filename goes on. Is there a way to use this instead of the huge regex in my command for source 3?