exiftools change hour from alphabetical filename order - bash

Question

I want to change the hours all all jpeg files, already sorted by alphabetical order.
I sort my album by hand, then I rename the files in alphabetical order. But, If I push this file in Google Photo, the order is remove.
So, I want to change only the time incrementally to respect the alphabetical order, the order of my album.
I work with Ubuntu.
Any idea ?

Answer 1

Here is a little bash script that should get you started. It processes all the JPG/JPEG files in the current directory, one at a time using jhead. It extracts the date/time from the file and checks if it is a different day from the previous file. If it is a new day, it starts the hours, minutes and seconds at 0, i.e. midnight on the new day. If it is the same day as the previous file, it increments the seconds from the previous file - with overflow into minutes and hours.
That means the first file each day will come out with timestamp midnight, then next one that day will be 00:00:01, the next one will be 00:00:02 and so on. Of course, you can change the scheme.
#!/bin/bash
# Don't barf if no files or if files named with JPG,jpg,JPEG,jpeg
shopt -s nullglob
shopt -s nocaseglob
# Process files in current name order
for f in *.jpg *jpeg; do
echo Processing $f...
# Get current YMD, HMS in format yyyy:mm:dd and hh:mm:ss
read ymd hms < <( jhead "$f" | awk '/Date/{print $3,$4}')
[ ${#ymd} -lt 10 ] && { echo $f no date found - skipping; continue; }
[ ${#hms} -lt 8 ] && { echo $f no time found - skipping; continue; }
# Check if date has changed
if [ "$ymd" != "$lastymd" ]; then
# New day, reset hours, mins, secs to zero
hrs=0
mins=0
secs=0
else
((secs=secs+1))
[ $secs -eq 60 ] && { ((mins=mins+1)); secs=0; }
[ $mins -eq 60 ] && { ((hrs=hrs+1)); mins=0; }
[ $hrs -gt 23 ] && { echo ERROR: Too many photos today $ymd; exit 1; }
fi
newts=$(printf "%s-%02d:%02d:%02d" $ymd $hrs $mins $secs)
echo File: $f, current time: $ymd,$hms new time: $newts
#jhead -ts"$newts" "$f"
lastymd=$ymd
done
At the moment, it does nothing, but remove the # in front of jhead on the third from last line if you want it to actually modify your files.
PLEASE MAKE A BACKUP FIRST and run on a copy of a few files in a temporary directory.
Sample Output
File: IMG_4045.JPG, current time: 2015:06:21,08:49:34 new time: 2015:06:21-00:00:00
Processing IMG_4046.JPG...
File: IMG_4046.JPG, current time: 2015:06:21,08:49:36 new time: 2015:06:21-00:00:01
Processing IMG_4047.JPG...
File: IMG_4047.JPG, current time: 2015:06:21,08:49:37 new time: 2015:06:21-00:00:02
Processing IMG_4048.JPG...
File: IMG_4048.JPG, current time: 2015:06:21,08:49:39 new time: 2015:06:21-00:00:03
Processing IMG_4049.JPG...
File: IMG_4049.JPG, current time: 2015:06:21,08:49:41 new time: 2015:06:21-00:00:04
Processing IMG_4052.JPG...
File: IMG_4052.JPG, current time: 2015:06:21,15:13:43 new time: 2015:06:21-00:00:00
Processing IMG_4053.JPG...
File: IMG_4053.JPG, current time: 2015:06:21,15:13:45 new time: 2015:06:21-00:00:01
Processing IMG_4054.JPG...
File: IMG_4054.JPG, current time: 2015:06:21,15:22:51 new time: 2015:06:21-00:00:02

Answer 2

The code is very good. I change a little to fixe some bugs or add features.
# Don't barf if no files or if files named with JPG,jpg,JPEG,jpeg
shopt -s nullglob
shopt -s nocaseglob
hrs=0
mins=0
secs=0
# Process files in current name order
for f in *.jpg *.jpeg *.mp4 *.mpg *.mov *.3gp *.gif *.png *.tif; do
echo Processing $f...
# Get current YMD, HMS in format yyyy:mm:dd and hh:mm:ss
read ymd hms < <( jhead "$f" | awk '/Date/{print $3,$4}')
[ "${ymd}" = "" ] && { ymd = "$lastymd"; }
[ ${#ymd} -lt 10 ] && { echo "$f no date found"; ymd="$lastymd"; }
[ ${#hms} -lt 8 ] && { echo "$f no time found"; ymd="$lastymd"; }
# Check if date has changed
if [ "$ymd" != "$lastymd" ]; then
# New day, reset hours, mins, secs to zero
hrs=0
mins=0
secs=0
else
((secs=secs+1))
[ "$secs" -eq 60 ] && { ((mins=mins+1)); secs=0; }
[ "$mins" -eq 60 ] && { ((hrs=hrs+1)); mins=0; }
[ "$hrs" -gt 24 ] && { echo ERROR: Too many photos today $ymd; exit 1; }
fi
newts=$(printf "%s %02d:%02d:%02d" $ymd $hrs $mins $secs)
echo File: $f, current time: $ymd,$hms new time: $newts
exiftool -overwrite_original -m "-alldates=$newts" "$f"
exiftool -overwrite_original -m '-DateTimeOriginal>FileModifyDate' "$f"
lastymd=$ymd
done