Change file (pictures, videos) timestamp from filename

Question

When moving files around tru different dirs and across PC / smartphone, timestamp for last modified date usually get reset to the very datetime of move / copy operation. This lead to files being non-chronologically sorted in some apps (Gallery), quite annoying especially for Images and Videos.

Usually these kind of files follows the naming convention of IMG_YYYYMMDD_HHMMSS.jpg for Images and VID_YYYYMMDD_HHMMSS.mp4 for Videos. So I thought about combining touch and extracting character from filenames, the timestamp being in effect part of the filename itself.

I found this script at Ephestione's HQ for i in IMG*.jpg; do busybox touch -t ${i:4:8}${i:13:4}.${i:17:2} $i; done but works in terminal only. I tried to make a script out of it but it doesn't work (see below)

#!/system/bin/sh
#change timestamp for images filename IMG_YYYYMMDD_HHMMSS.jpg 
for i in IMG_*.jpg
do
    touch -t ${i:4:8}${i:13:4}.${i:17:2} $i
done

#change timestamp for whatsapp images IMG-YYYYMMDD-WAnnnn.jpg
for i in IMG-*WA*.jpg
do
    touch -t ${i:4:8}1234 $i
done

#change timestamp for videos filename VID_YYYYMMDD_HHMMSS.mp4
for i in VID_*.jpg
do
    touch -t ${i:4:8}${i:13:4}.${i:17:2} $i
done

#change timestamp for whatsapp videos IMG-YYYYMMDD-WAnnnn.mp4
for i in VID-*WA*.mp4
do
    touch -t ${i:4:8}1234 $i
done

Ideally I'd like to put a script like this in the top level DCIM or Pictures directory and have it process all the Images and Videos in the subdirs. Of course I'm rooted.

Answer 1

Remove from the script the .${i:17:2} in for loop.

It should be:

#!/system/bin/sh
#change timestamp for images filename IMG_YYYYMMDD_HHMMSS.jpg 
for i in IMG_*.jpg
do
    touch -t ${i:4:8}${i:13:4} $i
done

#change timestamp for whatsapp images IMG-YYYYMMDD-WAnnnn.jpg
for i in IMG-*WA*.jpg
do
    touch -t ${i:4:8}1234 $i
done

#change timestamp for videos filename VID_YYYYMMDD_HHMMSS.mp4
for i in VID_*.jpg
do
    touch -t ${i:4:8}${i:13:4} $i
done

#change timestamp for whatsapp videos IMG-YYYYMMDD-WAnnnn.mp4
for i in VID-*WA*.mp4
do
    touch -t ${i:4:8}1234 $i
done

Note that the images and videos from WhatsApp according to your script have the same time 12:34.

Edit: To also go through subdirectories, change the for loops as followed:

for i in `find . -type f -name "IMG_*..jpg"`
do

j=`basename $i` 

echo $j

touch -t ${j:4:8}${j:13:4} $i


done

Explanation:

find . -type f -name ".mp5"`: find files ( -type t) whose names contains " IMG_.jpg" ( -name "IMG_*.jpg") in the current directory ( . ) and subdirectories.

j= basename $i : Get the filename (not the entire path), and assign it to j.

touch -t ${j:4:8}${j:13:4} $i : Change the file's modification time based on the date and time retrieved from ${j:4:8}${j:13:4} .