Desktop Pictures Cropper

This repository contains a Bash script to crop a set of images so that they can be used as native desktop pictures. The resulting images have the same high resolution as the stock macOS desktop pictures.

You Have

Before you can use the tool in this repository out of the box, you need the following tools preinstalled

• a recent version of exiftool (the script has successfully been tested with version 10.59)
• a recent version of ImageMagick that ships with the convert programme (the script has successfully been tested with ImageMagick 6.9.9-26 Q16 x86_64 2018-03-07)

Moreover, you need

• a collection of landscape or portrait images
• to decide how to crop each image

You Want

After cropping the images, you get

• 5120px x 2880px high resolution landscape desktop pictures
• 2880px x 5120px high resolution portrait desktop pictures

Here, the images are output to corresponding sub-directories named Landscape and Portrait and can be used as macOS desktop pictures as is. Note that the final image size can be configured if needed. See the FAQs for details.

Pre-Sorting the Images

The cropping script requires your input in deciding which section of the image to crop. The section to crop is determined by the folder the image is located in. Here, folder names are chosen to represent the area that is unaffected by the cropping.

Landscape Images

There are three options available for landscape images:

1. North
2. Center
3. South

Consider the following example of a lovingly handcrafted example landscape image

The items in the image roughly represent

• the sun in the upper right hand corner,
• two mountains in the middle, and
• a pond in the bottom left hand corner.

North

This option preserves the top section of the image and clips a bottom section of the image. For the example landscape image, the resulting cropped image is

Here, note how the pond at the bottom left hand corner has been cropped.

Center

This option preserves the centre section of the image and clips an equal section of the top and bottom of the image. For the example landscape image, the resulting cropped image is

Here, note how the sun in the upper right hand corner as well as the pond at the bottom left hand corner have been cropped.

South

This option preserves the bottom section of the image and clips a top section of the image. For the example landscape image, the resulting cropped image is

Here, note how the sun in the upper right hand corner has been cropped.

Portrait Images

There are three options available for portrait images:

1. East
2. Center
3. West

Consider the following example of a lovingly handcrafted example portrait image

The items in the image again roughly represent

• the sun in the upper left hand corner,
• two mountains in the middle, and
• a pond in the bottom right hand corner.

East

This option preserves the right hand section of the image and clips a section on the left hand side of the image. For the example portrait image, the resulting cropped image is

Here, note how the sun in the upper left hand corner has been cropped.

Center

This option preserves the centre section of the image and clips an equal section of the left and right hand side of the image. For the example portrait image, the resulting cropped image is

Here, note how the sun in the upper left hand corner as well as the pond at the bottom right hand corner have been cropped.

In order to avoid duplication, the same Center folder is used for both landscape and portrait images.

West

This option preserves the left hand section of the image and clips a section on the right hand side of the image. For the example portrait image, the resulting cropped image is

Here, note how the pond in the bottom right hand corner has been cropped.

Execution

The stand-alone Bash script cropper.sh is located in the root folder. It requires an <input-directory> of pre-sorted background images (see above for details) as well as an <output-directory> where to write the cropped images to. In case the <output-directory> does not exist, it is created.

Note that all landscape images are eventually located in <output-directory>/Landscape/. All portrait images are eventually located in <output-directory>/Portrait/.

All pre-sorted images in Originals/ can be cropped and output to Cropped/ via

cropper.sh "Originals/" "Cropped/"

Output File Naming and Caching

Each image <name>.<suffix> located in the input directory is eventually converted to <name>.jpg in the output directory. Here, <suffix> is a file extension convert can handle.

As converting and cropping images can be a time consuming task, the Bash script treats each file <name>.jpg in the output directory as the converted and cropped image of <name>.<suffix>. Hence, <name>.<suffix> is assumed to have already been converted and is subsequently ignored.

FAQs

What's the Resolution of the Resulting Landscape Desktop Pictures?

The cropped landscape desktop pictures are 5120px x 2880px. Note that this is also the resolution of the stock macOS desktop pictures in /Library/Desktop Pictures

What's the Resolution of the Resulting Portrait Desktop Pictures?

The cropped portrait desktop pictures are 2880px x 5120px.

How Can I Change the Resolution of Landscape Images?

The cropping values for landscape images are defined in variables

• LANDSCAPE_WIDTH
• LANDSCAPE_HEIGHT

at the beginning of cropper.sh. Adjust them as needed.

How Can I Change the Resolution for Portrait Images?

The cropping values for portrait images are defined in variables

• PORTRAIT_WIDTH
• PORTRAIT_HEIGHT

at the beginning of cropper.sh. Adjust them as needed.