image-compressor

(tl;dr) compress your images in .jpg format into subfolders sorted by years with reduced filesize.
For videos, see also: video-compressor

Use-case:

If you run out of storage on your smartphone and don't want to spend hours deleting and sorting out pictures, one easy solution is to simply reduce the file-size of your images on the backup device (Computer/HDD/NAS?) by using this script and shove them back to your phone.

Notes:

• The image_compressor script only deals with .jpg files.
• By default, file size will be reduced to about 10-25% of the original size, while maintaining absolutely acceptable quality (see also: Quality adjustments).
• For every .jpg the year of its creation is taken eighter from metadata or one of different fallback option (see also: Further Reading)
• No files will be deleted!
• A directory 'IMG_compressed' is created which will hold the subdirectories IMG_2019, IMG_2020 ... per year respectively.
• .jpg files that have weird numbers after the extension (as i experienced in my case) are copied without changes.
• Files without '.jpg' are being ignored.
• The image-compressor does not run through subdirectories.

Simply place image_compressor.py at the place your pictures are sitting and run it.

Installation (Unix-like, MacOS)

Assuming Python (version >= 3.4) is installed, in terminal:

clone this repository, cd into it:

    git clone https://github.com/warneat/image-compressor && cd image-compressor

Install dependencies:

    pip3 install -r requirements.txt

copy the script to your image folder e.g:

    cp image_compressor.py ~/foo/bar/images

Optionally, clean up/delete repository with

    cd .. &&  sudo rm -r image-compressor

Run

In your image directory run the script with

    python3 image_compressor.py
or
    ./image_compressor.py

On Windows

• Download this repository or git clone https://github.com/warneat/image-compressor like above.
• Install dependencies: Command-Line from within the new folder pip3 install -r requirements.txt
• move the image-compressor.py script to desired location and run it from there with python .\image_compressor.py

Quality adjustments

• 2 settings are available:
• overall quality-value, by default set to quality=50
• reduction of image-resolution (pixles) is off by default (dividing by 2 further reduces filesize by factor 0.25!)

To modify settings: in lines 52-64

• change quality=xx to your liking and/or
• uncomment (remove #) and adjust values

Further reading

• If the information is not available in the 'exif data', the file name is analyzed for common naming-patterns (e.g.) IMG_20220301_134230.jpg, Screenshot_20220301_134230.jpg or similar. Next fallbacks are the 'OS-known' creation-time, which is often not as acurate, especially in case of Linux, where 'YYYY' is used instead.

• The script runs on 4 processes (Raspberry Pi: All 4 cores 100%) :)

• As the processing might take hours or days for a large amount of data, when accessing via remote/ssh you might want to use screen (ultra-quick tutorial) to keep it running in background without an open terminal session.
  In a nutshell: Install it, $screen to start, [do stuff], ctr+a and d to detach. Reattach with $screen -r

• To automate (image) backups e.g Phone to NAS/Cloud-Server/Online-Account... i highly recommend the app FolderSync

Feedback is very much apprechiated