Convert images to JPEG on Finder

2021-01-09

The format of photos taken by iPhone is “.heic” (High Efficiency Image File Format (Wikipedia)). It’s fine as long as I see them on Mac. But sometimes I need to covert it to JPEG (for blogging .etc)

How to convert it easily?

We can enhance Finder Quick Actions with Automator which is pre-installed on macOS.

You can download this workflow from my GitHub repo(ecpplus/shell-utils)

Convert it on command line

sips

By default, macOS has image processing cli named sips. It is located at /usr/bin/sips. There are bunch of options, but for now I only use format conversion.

Converting any image to jpeg command is below;

sips -s format jpeg $input_path --out $output_path

format output path

Output path should be foobar.jpg. On shellscript, we can easily format it from original path.

INPUT="/foo/bar/IMG_1234.heic"
echo ${INPUT%%.*}.jpg

=> /foo/bar/IMG_1234.jpg

support multiple images input

Now, I’d like to convert multiple images at once. We can use for loop like this;

for f in "$@"
do
  sips -s format jpeg "$f" --out "${f%%.*}".jpg
done

Make Automator workflow

Launch Automator.app in Applications.
Create a new workflow from File (⌘N)
Choose Quick Action
Define work flow as shown below
1. Find Run Shell Script from actions.
2. Workflow receives current image files in Finder.app
3. Type shell script.
```
for f in "$@"
do
  sips -s format jpeg "$f" --out "${f%%.*}".jpg
done
```
Then save and name this workflow.
That’s it. You can now use it on Finder.