Sikora Image Quality

Control the quality WordPress uses when it generates and saves images, with separate settings for JPEG and the WordPress image editor.

License: GNU General Public License v2.0 or later

For GitHub. Plugin documentation source of truth: readme.txt.

Description

When you upload an image, WordPress creates multiple resized copies (thumbnail, medium, large, and other sizes). WordPress compresses those files using a default quality of 82. That favors smaller files, but it can cause visible compression artifacts. Higher values preserve detail but use more disk space and bandwidth.

Why these settings are needed

WordPress's default may not match your site. Photography and portfolio sites often need higher quality. Sites with limited storage may prefer lower values. This plugin lets you set the quality WordPress uses without writing custom code.

What the plugin does

It adds Settings → Sikora Image Quality with two sections:

• JPEG Quality — quality for generated JPEG images. Affects JPEG (.jpg, .jpeg) only.
• WordPress Editor Quality — quality when WordPress's image editor saves images. Affects JPEG, WebP, AVIF (WordPress 6.5+ when your server supports it), and PNG. PNG is lossless, so the quality value has little or no visual effect.

In each section you get:

• A quality slider and number field kept in sync (integers 1–100). Plugin default: 100. WordPress default shown on screen: 82.
• A filter priority slider and number field kept in sync (integers 1–999). Plugin default: 99. WordPress default shown on screen: 10.

What filter priority does

WordPress runs filters in priority order. Lower numbers run earlier; higher numbers run later. A later callback can override an earlier one. WordPress's default priority is 10. This plugin defaults to 99 so its quality settings usually apply even if another plugin or theme also changes image quality. Lower the priority if you want another plugin to take precedence.

Your settings apply only to images generated or re-saved after you save them. Existing thumbnails are not changed automatically. Uninstalling the plugin removes its settings from the database.

Installation

1. Upload the sikora-image-quality folder to /wp-content/plugins/, or install the zip via Plugins → Add New → Upload Plugin.
2. Activate Sikora Image Quality on the Plugins screen.
3. Open Settings → Sikora Image Quality and set your quality and filter priority values.

Frequently Asked Questions

Why change image quality?

WordPress defaults to 82. Raise it for more detail, or lower it for smaller files.

What does filter priority do?

It controls whether this plugin's quality values run before or after other plugins that change the same settings. Use a higher value (such as 99) if another plugin is overriding you.

Which file formats are affected?

• JPEG Quality: JPEG (.jpg, .jpeg) only.
• WordPress Editor Quality: JPEG, WebP, AVIF (when supported), and PNG.

Will existing images change?

No. Only new or re-saved generated images use the new settings.

Changelog

3.0.0

• Settings screen with JPEG Quality and WordPress Editor Quality sections.
• Synced quality controls (1–100, default 100) and filter priority controls (1–999, default 99).
• Shows WordPress defaults (quality 82, filter priority 10) and which file types each setting affects.
• Removes plugin settings from the database on uninstall.

Upgrade Notice

3.0.0

New settings screen for JPEG and editor quality. Review Settings → Sikora Image Quality after upgrading.