conversion of a PNG file/image to a JPEG file/image with AppleScript

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Level 1

4 points

conversion of a PNG file/image to a JPEG file/image with AppleScript

So I'm trying to convert a screenshot (PGN) on my desktop to a JPEG file. I'm using the save command from the Image Event application. I always run into the error -1700: unable to make type reference. Even when I execute the example from the developers.apple.com:

[Mac Automation Scripting Guide: Manipulating Images]

I also tried converting the alias object to a file object (set imagefile to theImage as «class furl»), but to no avail:

-- Prompt for an image

set theImageFile to choose file of type "public.image" with prompt ""

set theOutputFolder to (path to desktop folder as string)

-- Launch Image Events and open the image

do shell script "> $HOME'/Desktop/temp-01.jpg'"

tell application "Image Events"

launch

open theImageFile

set theImage to theImageFile

set target to "Macintosh HD:Users:siemhuijsman:Desktop:temp-01.jpg"

set imagefile to theImage as «class furl»

save imagefile as JPEG in target

close

log theImageFile

end tell

I would be much helped if somebody can explain the error that occurs and perhaps a way to get the job done.

Thank you in advance,

Siem Huijsman

MacBook Pro 16″, macOS 14.0

Posted on Oct 4, 2023 2:38 PM

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Answer 1

MrHoffman

Level 10

151,467 points

Oct 4, 2023 3:10 PM in response to siemhuijsman

AppleScript is good for scripting GUI apps, and other such.

It’s not something I’d usually choose for performing non-GUI-related tasks.

Here is the built-in graphics conversion tool, sips:

sips -s format [image type] [file name] --out [output file]

Here is an example of using the built-in shell command to perform the requested conversion.

sips --setProperty format jpeg Whatever.png --out Whatever.jpg

The next question here then becomes how you will call this conversion tool. The command can be invoked from AppleScript, if that is your wont. There are other ways to call a script.

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