image_downsize

Source code

function image_downsize($id, $size = 'medium') {



	if ( !wp_attachment_is_image($id) )

		return false;



	$img_url = wp_get_attachment_url($id);

	$meta = wp_get_attachment_metadata($id);

	$width = $height = 0;

	$is_intermediate = false;

	$img_url_basename = wp_basename($img_url);



	// plugins can use this to provide resize services

	if ( $out = apply_filters('image_downsize', false, $id, $size) )

		return $out;



	// try for a new style intermediate size

	if ( $intermediate = image_get_intermediate_size($id, $size) ) {

		$img_url = str_replace($img_url_basename, $intermediate['file'], $img_url);

		$width = $intermediate['width'];

		$height = $intermediate['height'];

		$is_intermediate = true;

	}

	elseif ( $size == 'thumbnail' ) {

		// fall back to the old thumbnail

		if ( ($thumb_file = wp_get_attachment_thumb_file($id)) && $info = getimagesize($thumb_file) ) {

			$img_url = str_replace($img_url_basename, wp_basename($thumb_file), $img_url);

			$width = $info[0];

			$height = $info[1];

			$is_intermediate = true;

		}

	}

	if ( !$width && !$height && isset($meta['width'], $meta['height']) ) {

		// any other type: use the real image

		$width = $meta['width'];

		$height = $meta['height'];

	}



	if ( $img_url) {

		// we have the actual image size, but might need to further constrain it if content_width is narrower

		list( $width, $height ) = image_constrain_size_for_editor( $width, $height, $size );



		return array( $img_url, $width, $height, $is_intermediate );

	}

	return false;



}