Resize and crop image from center with PHP

Sometimes I need to not only resize the image, but also to change its size by removing unnecessary edges for new size. This function changes image size and if the height or width is too large after resizing then the edges are cut off from the center. Input image formats are jpeg, gif, png.

//resize and crop image by center
function resize_crop_image($max_width, $max_height, $source_file, $dst_dir, $quality = 80){
	$imgsize = getimagesize($source_file);
	$width = $imgsize[0];
	$height = $imgsize[1];
	$mime = $imgsize['mime'];

	switch($mime){
		case 'image/gif':
			$image_create = "imagecreatefromgif";
			$image = "imagegif";
			break;

		case 'image/png':
			$image_create = "imagecreatefrompng";
			$image = "imagepng";
			$quality = 7;
			break;

		case 'image/jpeg':
			$image_create = "imagecreatefromjpeg";
			$image = "imagejpeg";
			break;

		default:
			return false;
			break;
	}
	
	$dst_img = imagecreatetruecolor($max_width, $max_height);
	$src_img = $image_create($source_file);
	
	$width_new = $height * $max_width / $max_height;
	$height_new = $width * $max_height / $max_width;
	//if the new width is greater than the actual width of the image, then the height is too large and the rest cut off, or vice versa
	if($width_new > $width){
		//cut point by height
		$h_point = (($height - $height_new) / 2);
		//copy image
		imagecopyresampled($dst_img, $src_img, 0, 0, 0, $h_point, $max_width, $max_height, $width, $height_new);
	}else{
		//cut point by width
		$w_point = (($width - $width_new) / 2);
		imagecopyresampled($dst_img, $src_img, 0, 0, $w_point, 0, $max_width, $max_height, $width_new, $height);
	}
	
	$image($dst_img, $dst_dir, $quality);

	if($dst_img)imagedestroy($dst_img);
	if($src_img)imagedestroy($src_img);
}
//usage example
resize_crop_image(100, 100, "test.jpg", "test.jpg");