Support » Plugin: Image Regenerate & Select Crop » Quality setting with/without optimization plugin

  • Resolved Gal Baras

    (@galbaras)


    Hi Lulia,

    The default quality setting for regenerating images is 100%, but the setting used by WordPress is 82%. I think 82% should therefore be the default.

    In some cases, it may make more sense to use 100%, like when there is an image optimization plugin installed, because the thumbnail will be re-processed anyway and 100% gives more information for the optimizer.

    To make changing this easier, why not have a global setting that can be changed for all sizes, and then allow each size to have its own override (0 == Inherit)?

Viewing 3 replies - 1 through 3 (of 3 total)
  • nosilver4u

    (@nosilver4u)

    Gal and I were chatting about this via email, and I much like his suggestion on the usability side of things. Trying to change multiple quality settings was very tedious and cumbersome.

    As to the validity of using quality 100, I would first like to point out that WP decreased the quality (from 90 to 82 several years ago), because they found additional savings (and thus speed) could be had without affecting the user experience (based on real user tests). Deviating from that is not a great idea, but what are the consequences if you do?

    To find out, I ran a small set of tests (on six images). Changing the quality level from 82 to 100 resulted in over 600% increase in file sizes. That is a huge difference in page speed, and can create a really poor experience for end-users, causing the site owner to lose out on sales, traffic, and everything that really matters to them.

    Now, we did one additional test, which was to compare those image after processing by a plugin like EWWW Image Optimizer, using our Premium compression. The difference in size still averaged 23.5% after applying our industry-leading compression to the thumbnails. I certainly wouldn’t give up that much file-size just for a tiny bit more quality.

    In previous tests, we’ve found you can go up to about quality 90 before you start seeing such dramatic (6x) size increases, but going above that gets out of control quickly. See also https://docs.ewww.io/article/12-jpg-quality-and-wordpress

    • This reply was modified 2 months ago by nosilver4u.
    Plugin Author Iulia Cazan

    (@iulia-cazan)

    Thank you both for the tests and details!
    I will also run some tests and make the necessary adjustments in the plugin.

    Plugin Author Iulia Cazan

    (@iulia-cazan)

    Hi
    The new version is available, it includes the discussed changes.
    Please test and let me know how it goes.

    Regards,
    Iulia

Viewing 3 replies - 1 through 3 (of 3 total)
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