Add a safe WP-CLI command for resizing oversized original uploads

[szepeviktor]

Feature Request

WordPress and WP-CLI provide excellent tools for generating image sub-sizes, but there is no first-class way to process oversized original uploads in a controlled, scriptable manner.

Many sites accumulate large camera originals that are far beyond their actual display needs. This increases storage, backup, CDN, and transfer costs. WordPress’s automatic large-image handling does not solve every existing-media or site-policy scenario.

I propose an opt-in command such as:

wp media resize-originals --max-dimension=1920 --quality=91 --dry-run

The command would:

• process original uploads in bounded batches;
• support JPEG, PNG, and WebP;
• provide a dry-run with estimated storage savings;
• require explicit confirmation before destructive changes;
• preserve a recoverable backup or offer a documented backup strategy;
• update only relevant attachment metadata;
• never regenerate unrelated sub-sizes unless explicitly requested;
• report progress and failures clearly.

@swissspidy is my secret spy

[szepeviktor]

my hack: https://github.com/szepeviktor/wordpress-website-lifecycle/blob/master/tools/resize-original-media.php#L23

[swissspidy]

Thanks for opening!

Related:

https://make.wordpress.org/core/2019/10/09/introducing-handling-of-big-images-in-wordpress-5-3/

https://github.com/WordPress/wordpress-develop/blob/ad2405c10e4d6311464ff40d75435ad95bb8a844/src/wp-admin/includes/image.php#L263-L284

Worth noting that with big_image_size_threshold the original is still uploaded/preserved, but the 'large' image size is the scaled down version. Question is whether we should do the same or do a destructive resize.

It also only affects new uploads, not existing attachments. So this proposed command would fill that gap.

• process original uploads in bounded batches

In line with wp media regenerate [<attachment-id>...], this could be wp media resize-originals [<attachment-id>...], so it's up to the caller to query & resize attachments in batches. We don't do batching for wp media regenerate --yes either.

• support JPEG, PNG, and WebP

Depends on what WordPress/server support.

• provide a dry-run with estimated storage savings;

Sounds complex, not sure if that is easily doable.

• preserve a recoverable backup or offer a documented backup strategy;

I'd say it's up to the caller to back up files if needed. We could perhaps add a flag to control whether to keep the original (like big_image_size_threshold) or not.

[szepeviktor]

On thing to note:
on a test site the estimated disk space gain is 11.96 GB across 4411 original uploads