Comments on: Converting Image File Formats with the Command Line & sips

By: Lauri Ranta

Lauri Ranta — Mon, 21 Jan 2013 12:30:27 +0000

One shortcoming with sips (and Automator and Preview) is that they always use a resizing method like bilinear in CS applications, so images that are made smaller can look blurry unless you add sharpening to them manually. And sips doesn't have many commonly needed resizing or cropping options.

It's probably better to learn to use ImageMagick. This would make images smaller if they are 501px or wider and convert them to jpg:

for f in *.png; do convert -filter lanczos2 -format jpg -quality 90 -resize '500x>' "$f" "${f%png}jpg"; done

mogrify modifies images in place:

mogrify -filter lanczos2 -resize 70% *.png

By: Bern

Bern — Thu, 17 Jan 2013 18:32:51 +0000

Picasa, all graphic and from anywhere in the pictures, preview or thumbnails just hit export and choose your size

By: Paul

Paul — Fri, 11 Jan 2013 22:51:34 +0000

Very smart, love this thanks!

By: Matt

Matt — Fri, 11 Jan 2013 22:03:54 +0000

If you change the batch command to use bash variable pattern substitution, then you can prevent the resulting file name from having two extensions.
Example 1:

for i in *.jpeg; do sips -s format png $i –out Converted/${i%jpeg}png;done

Example 2:
for i in *.jpeg; do sips -s format png $i –out Converted/${i/%\.jpeg/\.png};done

By: Steebz

Steebz — Fri, 11 Jan 2013 19:34:49 +0000

I do this with Preview, no offense to the unix gods but I think it’s a lot easier.

By: adam

adam — Fri, 11 Jan 2013 19:32:12 +0000

coreimage is more powerful,
but need to add the binaries