Tools to compress images to pagespeed standard

Question

I've been using Photoshop's "Save for web" option to save images that go on my website.

I keep the quality level at 60 which reduces picture quality slightly. When I increase the level pagespeed tells me that the images can further be compressed without loss.

I've also tried to do the same with Irfan View which has batch resize and compress which is great but results in the same pagespeed warning.

What can I do here? Is there any other tool I can use?

@MarkSetchell https://imgur.com/a/0Ng5V has been saved by Photoshop at 60 quality but pagespeed tells me it can further be reduced by 38KB. — Vinith Almeida, Aug 03 '17 at 13:25

Mark Setchell · Accepted Answer · 2017-08-03T14:31:17.927

2

Your image is 182kB as you posted it. With ImageMagick, you could down-sample the chroma and reduce the quality like this for 144kB:

convert ZtUUpS8.jpg -sampling-factor 4:2:2 -quality 75 result.jpg

Or, you could say you want an image no larger than 90kB like this:

convert ZtUUpS8.jpg -define jpeg:extent=90KB result.jpg

You can copy each of those and try them before installing ImageMagick :-)

Batch Processing

Make a back up of your files first and work on a COPY of a small subset until you get the idea.

If you are on Windows, and you want to do batch processing, you have two options:

1. Use ImageMagick's `mogrify` command:

mogrify -define jpeg:extent=90KB *.jpg

2: Use Windows' `FOR` loop

I don't use Windows, but there is a FOR loop described here, that would look something like this:

FOR /F %%G IN (*.jpg) DO convert "%%G" -define jpeg:extent=90KB "%%G"

edited Aug 03 '17 at 14:31

answered Aug 03 '17 at 13:38

Mark Setchell

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Thanks Mark. I checked these images on pagespeed and it says that it still can be reduced slightly, but that's okay. Now, is there something similar but with a GUI and batch processing that I can use to do the same? – Vinith Almeida Aug 03 '17 at 14:20
Are you on Windows? – Mark Setchell Aug 03 '17 at 14:20
Yes, Windows 10. – Vinith Almeida Aug 03 '17 at 14:22
1

I have updated the answer with some suggestions for batch processing. Sorry, I am not best on Windows. – Mark Setchell Aug 03 '17 at 14:32
Thank you Mark :) – Vinith Almeida Aug 03 '17 at 14:44

Tools to compress images to pagespeed standard

1 Answers1

1. Use ImageMagick's mogrify command:

2: Use Windows' FOR loop

1. Use ImageMagick's `mogrify` command:

2: Use Windows' `FOR` loop