add choice to generate filename instead of using uploaded filename

I like this module but wanted an option to have drupal generate a filename, rather than use the user's uploaded filename.

I added the following code in node_images_admin_settings

	$form['node_images_md5name'] = array(
		'#type' =>	'checkbox',
		'#title'=> t('override file name'),
		'#description' => t('Override uploaded filename with md5sum of file'),
		'#default_value' => variable_get('node_images_md5name', false),
	);

and patched the function _node_images_upload to

    // Save uploaded image
    $dest = _node_images_get_directory();
    $filename = variable_get('node_images_md5name', false) ? md5_file($file->filepath."/".$file->name) : $file->filename;
    if ($file = file_save_upload($file, $dest.'/'.$filename)) {
.
.
.

which allows me to have a configuration option to have drupal generate the filename for me. Instead of md5 other algorithms could be used, like timestamps or $_ENV[UNIQUE_ID] .

In case the same image is added again, the upload/file modules rename function applies and appends the counter to the filename.