Change attachment image uploads to have post_date corresponding to EXIF created date

[Otto42]

General idea is that if an image has EXIF data about its creation time, we should use that as the post_date in the attachment post, since the attachment post is the representation in WordPress of the attachment file.

Advantages: The posts will show their proper dates of creation by simply using the_date and similar functions.

This code will do it as a plugin. A patch would be much simpler and more generally beneficial.

add_filter('wp_update_attachment_metadata','attachment_redater',10,2);
function attachment_redater($data, $id) {
	if (!empty($data['image_meta']['created_timestamp'])) {
		$post=get_post($id);
		$post->post_date = gmdate('Y-m-d H:i:s', $data['image_meta']['created_timestamp']);
		wp_update_post($post);
	}
	return $data;
}

This is not so simple - post_date is implicitly assumed to be the date of upload:

• Currently the Media Editor shows you the "Upload Date" of the image. The plugin code you posted above changes that to the creation date, which is obviously wrong. Same thing when you view the attachment - it says "Published on [post_date]".

• WP defaults to storing media in yyyy/mm based folders - based on upload date. Again potential for confusion if you change post_date.

IMO it may be better to leave post_date as the uploaded date, and read the creation date metadata manually as/when needed.

#17485 has more discussion on this.