PHP生成缩略图

封装的方法函数： 

= $scale) {               
				//创建真彩图像资源（imagecreatetruecolor()函数使用GDLibrary创建新的真彩色图像）
                $newimg = imagecreatetruecolor($thumbWidth, $thumbHeight);
				//图像处理
                imagecopyresampled($newimg, $sourceImg, 0, 0, 0, 0, $thumbWidth, $thumbHeight, (($height) * $scale), $height);
                //以JPEG格式将图像输出到浏览器或文件
				ImageJpeg($newimg, $thumbSrc);
            }
			 //宽度优先
            if ($ratio < $scale) {             
                $newimg = imagecreatetruecolor($thumbWidth, $thumbHeight);
                imagecopyresampled($newimg, $sourceImg, 0, 0, 0, 0, $thumbWidth, $thumbHeight, $width, (($width) / $scale));
                ImageJpeg($newimg, $thumbSrc);
            }
        } else {
            if ($ratio >= $scale) {
                $newimg = imagecreatetruecolor($thumbWidth, ($thumbWidth) / $ratio);
                imagecopyresampled($newimg, $sourceImg, 0, 0, 0, 0, $thumbWidth, ($thumbWidth) / $ratio, $width, $height);
                ImageJpeg($newimg, $thumbSrc);
            }
            if ($ratio < $scale) {
                $newimg = imagecreatetruecolor(($thumbHeight) * $ratio, $thumbHeight);
                imagecopyresampled($newimg, $sourceImg, 0, 0, 0, 0, ($thumbHeight) * $ratio, $thumbHeight, $width, $height);
                ImageJpeg($newimg, $thumbSrc);
            }
        }
		//销毁图像
        ImageDestroy($sourceImg);
    }
?>

调用示例：