GPSDateStamp anomaly in iPhone 5s iOS 8.

[gmit2]

I just did some work with an iPhone 5s which lists the iOS version as "8" (not 8.0).  Interesting, 8.0 is only in beta at this date.  The listed GPSDateStamp (EXIF tag 001D) is "2014:07:186" other metadata has the create date as "2014:07:04". 

Looks like the beta version of iOS 8.0 is not quite ready for a release. 

Anyone else notice this sort anomally?

Gordon
www.eSleuth.com

[Phil Harvey]

I haven't seen this, but have seen other similar problems, so it is not surprising.

- Phil

[AnTu]

I just stumbled over the very same problem, now that I re-sort all my past 20 years of pictures.

On an iPhone 5S with iOS 8.0.2 the GPSDateTime show, as you described, as "YYYY:MM:DD hh:mm:ssZ", e.g. "2015:08:233 23:15:05.72Z". Using the -v3 option, you see the binary values as

Code Select Expand

  | | 13) GPSDateStamp = 2015:08:233
  | |     - Tag 0x001d (12 bytes, string[12] read as undef[12]):
  | |         0754: 32 30 31 35 3a 30 38 3a 32 33 33 00             [2015:08:233.]


It turns out that the day (DD) is given in day of the year. The 233^rd day of the year 2015 was the 21^st August, hence the correct date should have been "2015:08:21". Unfortunately I did not find an easy ExifTool option to convert it, setting the GPSDateTime also fails, but setting just the GPSDateStamp works!

I came up with a bash script that does the trick. Maybe somebody has a better idea, and I'd love to hear it.

Code Select Expand


DIRNAME="$( readlink -f "${1:-$(pwd)}" )"
IFS=,
exiftool -csv -m -q -r -if '$gpsdatetime' -GPSDateTime \"${DIRNAME%/}" | awk '
    BEGIN {
FS  = "[,: ]"
OFS = ","
}
        $4>31 {
                t=mktime($2" 1 "$4" "$5" "$6" "$7)
                print $1, strftime("%Y:%m:%d",t), strftime("%H:%M:",t)$7
            }
    ' | while read file date time
    do
        exiftool -m -overwrite_original_in_place -q -GPSDateStamp="$date" -GPSDateTime="$date $time" "$file"
    done

 

[Phil Harvey]

Smart.

GPSDateTime is a Composite tag based on GPSDateStamp and GPSTimeStamp, and isn't writable directly.

- Phil