ryzmaa
Last Updated: March 08, 2017
·
20.6K
· ninjabiscuit
Punnet

Use ImageMagick to create optimised and progressive JPGs

Use the following command to optimise a JPG and make it progressive:

convert -strip -interlace Plane -quality 80 input-file.jpg output-file.jpg 

Batch all the images in a folder like this:

for i in source/images/backgrounds/*.jpg; do convert -strip -interlace Plane -quality 80 $i $i; done  

With Carrierwave and MiniMagick you can create an optimise function like this:

def optimize
  manipulate! do |img|
      return img unless img.mime_type.match /image\/jpeg/
      img.strip
      img.combine_options do |c|
          c.quality "80"
          c.depth "8"
          c.interlace "plane"
      end
      img
  end
end

And use it in your uploader like this:

version :large do
  process :optimize
end

4 Responses
Add your response

10303
Icflorescu

I didn't know about -interlace, thanks for sharing :-)

over 1 year ago ·
18889
Eadde9d1ed7a958dd34d4f895bcd4a8c

Progressive JPEG doesn't work for me with MiniMagick 4.0.4.
Searching in the doc for an interlace method found no result: http://www.rubydoc.info/search/github/minimagick/minimagick?q=interlace

over 1 year ago ·
18890
Punnet

@caedes MiniMagic uses ImageMagics command line program mogrify which has an interlace feature (https://github.com/minimagick/minimagick#solution)

Full list of supported mogrify commands can be found here: http://www.rubydoc.info/gems/mini_magick/3.3/MiniMagick

over 1 year ago ·
24940
A32b325ca532dc2f9d86eb40aa9787b7

I wanna convert all images, including png, jpg, gif to progressive jpg and used this method, I got a new version of images, but the extension of file is not changed. For example, input.png only output progressive_input.png.

over 1 year ago ·