Pantheon Image Enrichment

Contributors: getpantheon, danielbachhuber
Tags: pantheon, images
Requires at least: 4.7
Tested up to: 5.0
Stable tag: 0.1.0
License: GPLv2 or later
License URI: https://www.gnu.org/licenses/gpl-2.0.html

Generate default alt text, block unsafe uploads, and enrich images using the Google Cloud Vision API.

Description

Supercharge your WordPress Media Library with a variety of enhancements via the Google Cloud Vision API:

• Generate default alt text for uploaded images without it. Uses the landmark or logo if one is detected in the image, otherwise generates a comma-separated list of descriptive labels.
• Block uploading of images deemed unfit for Google Safe Search. Default behavior is to reject any images deemed likely or very likely to be adult, spoof, medical, violence, or racy.
• Incorporate quadrant crop hints into the image crop process. Based on the machine-identified point of focus, automatically defines array( 'left', 'top' ), etc. for any image sizes with 'crop' => true.

Go forth and make awesome! And, once you've built something great, send us feature requests (or bug reports).

Installation

To install Pantheon Image Enrichment, follow these steps:

1. Install the plugin from WordPress.org using the WordPress dashboard.
2. Activate the plugin.

To install Pantheon Image Enrichment in one line with WP-CLI:

wp plugin install pantheon-image-enrichment --activate

WP-CLI Commands

This plugin implements a variety of WP-CLI commands. All commands are grouped into the wp pantheon image namespace.

NAME

  wp pantheon image

DESCRIPTION

  Generates default alt text and more.

SYNOPSIS

  wp pantheon image <command>

SUBCOMMANDS

  generate-alt-text      Generate alt text for attachments.

Implementation Details

If you're curious about how Pantheon Image Enrichment works, let's take a high-level walkthrough.

The Hooks class defines all of the integration points with WordPress:

• filter_wp_handle_upload_prefilter - At the very beginning of the upload process, this prefetches all Google Cloud Vision data we might want to use. Based on the fetched data, also rejects upload of unsafe images.
• action_add_attachment - Generates alt text if none exists when attachment object is saved to the WordPress database.
• filter_intermediate_image_sizes_advanced - Introduces quadrant-based crop hints (e.g. array( 'left', 'center' )) when generating cropped versions of the attachment.

Under the hood, the Hooks class calls the Enrich class for specific enrichment behaviors:

• generate_alt_text_if_none_exists - Generates alt text for an attachment if none exists.
• generate_alt_text_if_missing_or_previously_enriched - Generates alt text for an attachment if none exists or it was previously enriched.
• generate_alt_text_always - Always generates alt text, even if some exists already.
• get_likely_safe_search_violations - Gets any LIKELY or VERY_LIKELY Google Safe Search violations.
• get_quadrant_crop_suggestions - Gets quadrant-based crop suggestions for a given image.

Lastly, the GCV class is the workhorse that provides an interface to the Google Cloud Vision API.

Changelog

0.1.0 (June 25th, 2018)

• Initial release.