image_resize

Source code

function image_resize( $file, $max_w, $max_h, $crop = false, $suffix = null, $dest_path = null, $jpeg_quality = 90 ) {



	$image = wp_load_image( $file );

	if ( !is_resource( $image ) )

		return new WP_Error( 'error_loading_image', $image, $file );



	$size = @getimagesize( $file );

	if ( !$size )

		return new WP_Error('invalid_image', __('Could not read image size'), $file);

	list($orig_w, $orig_h, $orig_type) = $size;



	$dims = image_resize_dimensions($orig_w, $orig_h, $max_w, $max_h, $crop);

	if ( !$dims )

		return new WP_Error( 'error_getting_dimensions', __('Could not calculate resized image dimensions') );

	list($dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h) = $dims;



	$newimage = wp_imagecreatetruecolor( $dst_w, $dst_h );



	imagecopyresampled( $newimage, $image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);



	// convert from full colors to index colors, like original PNG.

	if ( IMAGETYPE_PNG == $orig_type && function_exists('imageistruecolor') && !imageistruecolor( $image ) )

		imagetruecolortopalette( $newimage, false, imagecolorstotal( $image ) );



	// we don't need the original in memory anymore

	imagedestroy( $image );



	// $suffix will be appended to the destination filename, just before the extension

	if ( !$suffix )

		$suffix = "{$dst_w}x{$dst_h}";