Wall in Malta displaying the words: If only I had paint

For years, I’ve been taking pictures of all kinds of things with my smartphone. The photo above, which is wall in Malta is just one example. Currently, I all these pictures in a folder without any kind of sorting. It has become large enough that I have no idea what this folder contains. I’d like to sort these images.

Deleting duplicate images

I’ve noticed that some images are duplicated. But how many really are?

I use fdupes to find automatically remove duplicate files:

fdupes -rdN Pictures/

This removes images that are perfect duplicates. But what about almost identical images? What about if a PNG was duplicated as a JPEG? I look for software helping me with that and find Geeqie. This tutorial explains how I can use Geekie to quickly find similar images. With that, I remove a few dozen more duplicate images.

Sorting images

For me, sorting images by year is sufficient. I don’t need to know where the images were taken or what they are about. If it’s important enough, I’ll remember anyway. So I try to sort them by year. The images’ Exif data is helpful for that. Given a directory of images (only images, no folders), this script creates a directory that is named after the year at which each photo was taken and then moves the photo inside the created directory.

#!/bin/bash

set -e

find Pictures/ -maxdepth 1 -type f -print0 | while IFS= read -r -d '' file
do
    # Bypasses any non-image files
    file "$file" | grep image > /dev/null
    if [ "0" != "$?" ]; then
        continue
    fi
    
    # Bypasses files that don't have Exif data
    exif="$(identify -verbose "$file" | grep "exif:")"
    if [ 0 != "$?" ]; then
        continue
    fi

    exif_year="$(echo "$exif" | grep exif:DateTimeOriginal | cut -d' ' -f6 | cut -d':' -f1)"

    if [ -n "$exif_year" ]; then
        echo "$file" '->' "$exif_year"
        test -d "$exif_year" || mkdir "$exif_year"
        mv "$file" "$exif_year"/
    fi
done

For instance, if there is one image from 2005 and one from 2018, it creates this directory structure:

2005
 -> one-image-from-2005.jpg
2018
 -> another-image-from-2018.jpg

A few photos do not have any Exif data, so I sort these by hand.

Creating value from useless images

After sorting those images, I realize a lot of them have no value for me personally. They don’t represent anything personal, public places, airports, etc. I briefly think about deleting them. But what if, instead, I put my “useless” images on a stock photo website?

These images may not be useful to me right now, but they may well be useful to someone else. Or maybe they’ll be useful to me in a few years and having a personal bank of images I can pick from would be cool.

So I try to understand how to remove private information from these images. They can contain Exif data, which sometimes contains private information. To avoid leaking it, I’m strip it all away:

find Pictures/ -type f -exec exiv2 rm {} \;

Now, if I want some photos to describe me as the photographer, I can include a copy right notice:

exiv2 -M"set Exif.Image.Copyright Copyright Conrad Kleinespel" copyrighted-photo.jpg

I also want to strip any potentially private information from the image names themselves. And the extensions of the images being somewhat odd — jpg, JPG, jpeg, JPEG — I’d like to replace it all with jpg. So I create another script for that:

#!/bin/bash

set -e

find Pictures/ -type f -print0 | while IFS= read -r -d '' file
do
    # Bypasses any non-image files
    file "$file" | grep image > /dev/null
    if [ "0" != "$?" ]; then
        continue
    fi

    sha1="`sha1sum "$file" | cut -d' ' -f1`"
    ext="`echo "$file" | grep -o '.[[:alnum:]]*$' | tr '[:upper:]' '[:lower:]'`"

    if [ "$ext" = ".jpeg" ]; then
        ext=".jpg"
    fi

    new_name="$sha1$ext"
    mv "$file" "$new_name"
done

This creates image names like 3914678325556c51762c3c709c322d4357b2163d.jpg, without any personally identifiable information.