# Another simple image optimizer

WordPress plugin to optimize uploaded images (jpg, png, gif, webp, svg) using the great [Spatie image-optimizer library][1] and binary files on your host system.

If you open your media library, switch to list mode and enable the new column "Optimized", you can click a link to optimize a previously uploaded image directly.

New uploaded images and all images sizes (thumbnails) are optimized automatically.

To update existing images, use the cli `wp media regenerate`, which also triggers the optimization chain. If you don't have cli access, some other addon, that regenerates existing thumbnails should work, too (not tested).

__Warning:__ Images are replaced with the optimized ones. Create a backup before testing this plugin - or don't use this plugin, if this is a deal breaker for you.

__Important:__ If the needed binaries aren't installed, this plugin won't optimize anything. Don't use this plugin, if you don't know, how to install them or if your web hoster doesn't provide them.

## Optimization tools

Spatie image-optimizer will use these optimizers if they are present on your system:

* [JpegOptim][7]
* [Optipng][9]
* [Pngquant 2][10]
* [SVGO 1][11]
* [Gifsicle][12]
* [cwebp][14]

You can find information about how to install the binaries in the [spatie image-optimizer README][2].

## Why another image optimization plugin?

After some research the first search results pages were full of SEO spam. I don't need a CDN. I don't want to send uploaded images via limited API access to a third party provider (who uses the same binaries anyway). I just want to upload huge jpg files and let some magic in the background remove all meta data and drastically shrink that file. Also I don't like ads and bloatware.

So to avoid SEO spam I began to search for "wordpress spatie", "wordpress jpegoptim" and "wordpress optipng" to find good candidates. I found some, but they didn't match my expectations (e. g. no gif support, outdated, only cli...). So I wrote my own implementation with the goal to keep it simple.

## Inspiration and similar projects

While searching existing plugins, that aren't bloated, I found the following interesting projects. If you don't like my plugin, maybe some of these fit your needs:

* https://github.com/TypistTech/image-optimize-command
  * only cli, needs wp-cli to be installed via composer
* https://github.com/ainsleyclark/squidge
  * looks really good, converts jpg and png to webp and avif formats
  * no pngquant support
  * no gif or svg support
* https://github.com/gsarig/slimage
  * only jpegoptim and optipng
* https://github.com/lstellway/wp-optimize-images
  * implemented psliwa/image-optimizer
  * installation only via composer as mu-plugin
* https://github.com/globalis-ms/wp-cubi-imagemin
  * also implemented psliwa/image-optimizer
  * installation only via composer

## Installation

Copy this repository into `wp-content/plugins` and name it `another-simple-image-optimizer`.

## Notes

I use `symfony/process` v6.0.x for PHP 8.0 compatibility. Since v6.1 it requires PHP 8.1.

I decided against the [`psliwa/image-optimizer`][3] library, because it doesn't support webp. Also `spatie/image-optimizer` is easier to configure and I was already familiar with it, because I used that in a different project.

The plugin name/slug `simple-image-optimizer` was taken, so I chose `another-simple-image-optimizer`.

## Development

* how to publish plugin
  * https://wordpress.org/plugins/developers/add/
  * https://developer.wordpress.org/plugins/wordpress-org/detailed-plugin-guidelines/
  * https://developer.wordpress.org/plugins/wordpress-org/
  * https://developer.wordpress.org/plugins/wordpress-org/how-your-readme-txt-works/
  * https://developer.wordpress.org/plugins/plugin-basics/header-requirements/
  * https://developer.wordpress.org/plugins/internationalization/how-to-internationalize-your-plugin/
* Sync git repo with wp svn
  * https://developer.wordpress.org/plugins/wordpress-org/how-to-use-subversion/
  * https://github.com/10up/action-wordpress-plugin-deploy
  * https://nabeel.blog/2016/10/24/wordpress-plugin-git-svn/
  * https://github.com/rayrutjes/wp-plugin-git-svn-sync
* How to find unique plugin slug
  * https://plugins.svn.wordpress.org/
  * https://wordpress.stackexchange.com/a/290402

### Update dependencies

```bash
composer update --no-dev -o
# composer update --no-dev --ignore-platform-reqs -o
```

### Publish new version

* Update version number in `plugin.php` and in `readme.txt`
* `git tag` like normal
* TODO: Somehow convert git tag to svn and send that to wp

### Submit initial version

```bash
git archive -o ../another-simple-image-optimizer.zip 0.1.1
```

## License

MIT

See [LICENSE][6] for more information.

## Credits and third party resources

The following libraries are used in this project (Thanks!):

* [spatie/image-optimizer][1] by Spatie, MIT license
* [symfony/process][5] by Fabien Potencier, MIT license
* [psr/log][4] by PHP Framework Interoperability Group, MIT license

These optimizers are used under the hood:

* [JpegOptim][7] by [Timo Kokkonen][8], GPL-3.0 license
* [Optipng][9] by Cosmin Truta, zlib license
* [Pngquant 2][10] by Kornel Lesiński, GPL-3.0 license
* [SVGO 1][11] by Kir Belevich, MIT license
* [Gifsicle][12] by [Eddie Kohler][13], GPL-2.0 license
* [cwebp][14] by Google Inc, [some kind of permissive license][15]

[1]: https://github.com/spatie/image-optimizer
[2]: https://github.com/spatie/image-optimizer#optimization-tools
[3]: https://github.com/psliwa/image-optimizer
[4]: https://github.com/php-fig/log
[5]: https://github.com/symfony/process
[6]: https://codeberg.org/raffaelj/wordpress-another-simple-image-optimizer/src/branch/main/LICENSE
[7]: https://github.com/tjko/jpegoptim
[8]: https://github.com/tjko
[9]: http://optipng.sourceforge.net/
[10]: https://pngquant.org/
[11]: https://github.com/svg/svgo
[12]: http://www.lcdf.org/gifsicle/
[13]: https://www.read.seas.harvard.edu/~kohler/
[14]: https://developers.google.com/speed/webp/docs/precompiled
[15]: https://chromium.googlesource.com/webm/libwebp/+/refs/heads/main/COPYING