説明
Our WordPress plugin offers precise control over image compression in your media library.
You can optimize the compression quality for each resized image, striking the perfect balance between visual appeal and fast page loading.
A real-time preview feature lets you instantly see the results of different compression levels.
Security is enhanced through an EXIF data removal function, which strips sensitive information like GPS coordinates from your uploaded images.
For advanced performance, the plugin utilizes WebP technology on compatible servers.
It automatically generates and serves WebP versions of your images to supporting browsers, replacing JPEG or PNG formats without manual URL adjustments.
This seamless optimization significantly improves Core Web Vitals (CWV), enhancing your site’s overall performance and search engine ranking.
- 画像タイプ (JPEG / PNG / WebP) とサイズ名のテーブルで品質レベルを設定できます。
- 未設定に対するデフォルト値を設定できます。
- 元画像の WebP 圧縮の品質レベルを設定できます。
オプションとして以下を設定できます。
- セキュアなファイル名の保証 (マルチバイトのファイル名を書き換える)
- Strip Exif Data
- Exif から Alt の自動生成 (JPEG のみ)
- 圧縮品質レベルのサフィックスを追加
- インターレース / プログレッシブの有効化
- WebP 生成の有効化
- Enable PNG8
- Optimize “srcset” Attribute
- Force Adding the Query String for Image Cache Clear
- Optimize Delay by WP-Cron
その他の機能
また、以下の機能があります。
- Add Some Custom Image Sizes
- Test Quality Level
- Change of Big Image Threshold
- 設定のリセット
- 再圧縮の実行
- Auto Re-Compression using WP-Cron
使い方
インストール・有効化後、WebP が自動生成されるようになり、小さな画像の圧縮率が高くなります。
必要であれば、設定を調整したらすべての画像を再圧縮してください。(自動的に圧縮率を変更した画像が生成されることはありません)
- インストール
- 有効にする
- 設定を変更します (必要な場合)
- アップロードされた画像を再圧縮します (必要な場合)
再圧縮を行う前に必ずバックアップを取っておいてください。
設定画面へのアクセス
- 設定画面
- 「画像の圧縮品質」を開きます
スクリーンショット
圧縮品質レベルの設定テーブル 
Test Quality Level 
オプション 
アップロード済み画像の再圧縮をサポート 
WebP 画像の自動生成
インストール
- Enter “Image Quality Control” in the plugin search field in your admin screen.
- Once you find this plugin, click “Install Now” to install.
(Alternative) Upload “stillbe-image-quality-control.zip” directly to your Plugins -> Add New in your admin screen.
(Alternative) Upload an unzipped “stillbe-image-quality-control” directory under the “/wp-content/plugins” directory. - WordPress のプラグインメニューからプラグインを有効にします。
- Leave image optimization to this plugin. Let’s enjoy WordPress!!
FAQ
-
Does the image loss quality if I change the quality level many times and recompress it?
-
No, it will not be lost.
When recompressing, resize and compress from the original image. -
If I generate some WebPs, do I need to rewrite the image URL in the articles?
-
There is no need to rewrite.
If user browser supports WebP, .htaccess will automatically deliver WebP instead of JPEG or PNG. -
Should I recompress it?
-
Not required.
If you want to compress the uploaded images with the new settings, recompress it.
Recompression is recommended when creating a new WebP. (WebP for uploaded images is not automatically generated) -
The image sharpness of WebP is not good.
-
Raise the quality level of WebP.
Test the file size and image quality to decide the quality level. -
Can EXIF data be deleted individually for each item?
-
It cannot be done.
You can only specify whether you want to delete all or keep it. -
Can I delete EXIF from uploaded images?
-
Yes, you can.
Recompression will delete the EXIF according to the current settings.
However, EXIF that have already been deleted cannot be restored. -
Does disabling the plugin stop the automatic delivery of WebP?
-
Yes, it will stop.
If you install ‘.htaccess’ properly in /wp-content/uploads, it can be delivered automatically even after it is stopped. -
Does the setting value of this plugin take precedence over ‘jpeg_quality’ hook?
-
Yes, it has priority. (Version 0.10.9+)
However, it is unstable which one is prioritized up to version 0.10.8. -
How to uninstall? Is there anything I need to do after uninstalling?
-
Just deactivate it from the plugins (admin screen) and then delete it.
There is no cache or database, so there is nothing you to do after uninstalling. -
If an image that was of poor quality is recompressed with higher quality, there will be no change in the image.
-
It is possible that the browser cache is still active.
Clear the browser cache or update this plugin to Version 1.2.0+. Version 1.2.0+ will clear the cache when there is a change in the image.
However, if the quality of the original image is low, it will not improve over that quality.
評価
貢献者と開発者
変更履歴
1.7.4
Fixed Fatal Error in GD environment.
1.7.3
Checked that it works with WordPress 6.8.
1.7.2
Checked that it works with WordPress 6.7.
1.7.1
Checked that it works with WordPress 6.4.
1.7.0
Checked that it works with WordPress 6.3.
1.6.0
Changed Requests_Transport_fsockopen class to WpOrg\Requests\Transport\Fsockopen class.
1.5.2
Fixed a bug that caused batch recompression to loop without finishing.
1.5.1
Fixed a bug that failed to set image quality when the size name was changed after an image size was added.
Changed the specification to display only the number of files instead of displaying the attachment id of the targets in the tab of recompression.
Fixed other minor bugs.
Checked that it works with WordPress 6.2.
1.5.0
Fixed an error when an empty file is passed during EXIF removal.
Checked that it works with WordPress 6.1.
1.4.0
Added process to strip EXIF data embeded in images.
1.3.0
Fixed an error that occurred with PHP 7.2 and older.
Checked that it works with WordPress 6.0.
1.2.4
Fix an issue where resized images were not generated when uploading WebP that WebP was not automatically generated to replace images in conventional format.
1.2.3
Fix the text domain in some translation functions.
1.2.2
Change translation function to wp.i18n.
Adjust the tab control of the setting screen.
1.2.1
Add an option to optimize delay by WP-Cron. cURL in version older than 7.32.0, decimal values cannot be used for timeout.
Chang the method of obtaining the modification date and time of the query string to clear the image cache.
Fix a bug in Imagick that WebP mime-type was not detected correctly.
Fix a bug in the quality test that the quality level of the original image might not be set to the set level.
1.2.0
Add an option to add a query string to clear the image cache.
Changed the interlace flag to be set separately for JPEG and PNG.
1.1,2
Add setting of target conditions for batch conversion.
Checked that it works with WordPress 5.9.
1.1.1
Fix a bug that toggle options could not be displayed when loading by the setting page opening other than the test image tab in the quality level test.
GD changed the initial value of PNG8 enablement to ‘false’ because transparent colors are not preserved when converted to PNG8 at sites that use the GD library.
1.1.0
Supports PNG8. Supports changing toggle options in quality level testing.
1.0.0
Official Release
Change of the quality levels can be set according to the size of the original image.
0.10.9
Fix a bug that the setting value of this plugin is not set except for ‘medium’ size when the quality level is set by ‘jpeg_quality’ hook.
0.10.8
Fix a bug that the default quality setting values are not used when the quality setting values are not set.
Add the function to display the saved setting values.
0.10.7
Increase the priority of the quality level setting for this plugin.
0.10.6
Fix the quality levels in compression informations table.
0.10.5
Add the quality level table for site icon.
Add single compression button to the Media Library page (list view).
Update translations.
0.10.4
Add compression informations to the Media Library page (list view).
Fix a bug that occasionally prevented setting the site icon.
0.10.3
Show the default value for toggle settings.
0.10.2
Fix because the deletion of 0.10.1 was not successful.
0.10.1
Delete the old files that remained when dividing into folders under /includes.
0.10.0
Tab the setting screen.
Fix some bugs.
0.9.1
Modulated the processes for extension plugin.
0.9.0
Fix some bugs.
Add the funcitions of extension plugin.
0.8.1
Fix a bug that the quality level cannot be set in the quality test.
Add the function to regenerate only one image.
0.8.0
Add the bellow functions;
1. Add Custom Image Sizes
2. Optimize “srcset” Attribute
3. Big Image Threshold
4. Images are automatically regenerated using WP-Cron
0.7.5
Compatible with WordPress 5.8.1.
Changed the default values.
0.7.4
Fix a bug that the setting values cannot reset.
0.7.3
Fix some bugs.
0.7.2
Changed the test image preview to an image size that takes into account the device pixel ratio.
0.7.1
Add the function to test quality level.
0.6.1
Update the description on the setting screen.
0.6.0
Compatible with WordPress 5.8. Fixed a bug that the original image WebP was not generated.
Updated to interrupt the recompression process.
0.5.3
WordPress のプラグインディレクトリにて初回リリース。
0.5.0
設定ページの項目を整理し、説明を追加。設定画面で設定した設定値が適応されるように変更。
0.4.0
設定ページの追加、Image Editor の選択時に WebP が有効なライブラリを優先するように変更。
0.3.1
アップロード画像を削除する際に WebP も同時に削除するように処理を追加。
0.3.0
WebP の生成に cwebp ユーティリティを使うように変更。
0.2.0
コアの Image Editor を拡張するクラスを追加し、GD / Imagick でリサイズ画像を作成するときに圧縮品質を個別に設定する。
0.1.0
‘wp_generate_attachment_metadata’ フックで GD 関数を使用してアップロード時にリサイズされた画像を上書きする。