imgix-wordpress / images-via-imgix

	public function replace_images_in_content( $content ) {

	    // Added null to apply filters wp_get_attachment_url to improve compatibility with https://en-gb.wordpress.org/plugins/amazon-s3-and-cloudfront/ - does not break wordpress if the plugin isn't present.

		if ( ! empty ( $this->options['cdn_link'] ) ) {

			if ( preg_match_all( '/<img\s[^>]*src=([\"\']??)([^\" >]*?)\1[^>]*>/iU', $content, $matches ) ) {

				foreach ( $matches[2] as $image_src ) {

					$content = str_replace( $image_src, apply_filters( 'wp_get_attachment_url', $image_src, null ), $content );

				}

			}

			if ( preg_match_all( '/<img\s[^>]*srcset=([\"\']??)([^\">]*?)\1[^>]*\/?>/iU', $content, $matches ) ) {

				}

			}

			if ( preg_match_all( '/<a\s[^>]*href=([\"\']??)([^\" >]*?)\1[^>]*>(.*)<\/a>/iU', $content, $matches ) ) {

				foreach ( $matches[0] as $link ) {

					$content = str_replace( $link[2], apply_filters( 'wp_get_attachment_url', $link[2], null ), $content );

				}

			}

		}

		return $content;

	}