Image scaling watermark PHP class

/**
* Image zoom watermark class
*
*/
class cls_photo
{
 protected $waterrate = 0.2; //The ratio of the watermark icon on the image
 protected $width = 300; //The default width of the thumbnail
 protected $height = 200; //Default height of thumbnail
 protected $padding = 5; //Distance from watermark image to edge
 protected $water_mark = "./water.png";
 protected $water_mark_pos = 5; //Watermark image position ( 1=upper left corner, 2=upper right corner, 3=lower left corner, 4=lower right corner, 5 center)
 protected $watermode = 0; // 0 does not print watermark when thumbnail 1 prints watermark when thumbnail
 protected $magick_handle; //Picture operation handle
 protected $format = array ( 'jpg', 'gif', 'png', 'jpeg' ); // Picture file format limitation
 protected $smallpic_mode = 2; // Default mode 0 is not generated Thumbnail, 1 is crop scaling, 2 is proportional scaling, 3 is scaling fill mode

 /**
 * Set image parameters
 *
 * @param $arg Image parameters can be put into the array multiple times as follows
 * @param $protected parameter value
 * array(
 * 'waterrate'=>0.2,
 * 'water_mark '=>'./water.png',
 * 'water_mark_pos'=>4,
 * 'smallpic_mode'=>1
 * );
 * @return ture/false
*/
 public function set_args ( $arg,$val="" )
 {
 $params = array ( 'waterrate','water_mark','water_mark_pos','smallpic_mode','watermode','width','height' );
 if ( is_array ( $arg ) )
 {
 foreach ( $arg as $k => ;$v )
 {
 if ( in_array ( $k,$params ) )
 {
 $this->$k = $v;
 }
 }
 }
 else
 {
 if ( empty ( $val ) )
 {
 return false;
 }
 else
 {
 if ( in_array ( $arg,$params ) )
 {
 $this->$arg = $val;
 }
 }
 }
 return true;
 }

 /**
 * Image scaling
 *
 * @param $src_file source file path
 * @param $dst_file destination file path
 * @return thumbnail image path/false
*/
 public function scale ( $src_file,$dst_file="" )
 {
 $dst_width = $this->width;
 $dst_height = $this->height;
 $mode = $this->smallpic_mode;
 $magic_water_handle = NewMagickWand();
 if ( !MagicReadImage ( $magic_water_handle, $src_file ) ) return false;

 //Type
 $srcext = strtolower ( MagickGetImageFormat ( $magic_water_handle ) );
 if ( $srcext=='bmp' )
 {
 $srcext = 'jpeg';
 }
 if ( !in_array ( $srcext,$this->format ) ) return false;
 //size
 $src_width = MagickGetImageWidth ( $magic_water_handle );
 $src_height = MagickGetImageHeight ( $magic_water_handle );

 //Crop zoom mode
 if ( $mode == 1 )
 {
 $pos_x=$pos_y = 0; //Crop Cut temporary position
 $src_widthc = $src_width;//Cut temporary width
 $src_heightc = $src_height;//Cut temporary height
 if ( $src_width/$src_height>$dst_width/$dst_height )
 {
 $src_widthc = $ SRC_HEIGHT*$ dst_width /$ dst_height;
 $ POS_X = ($ src_width-$ src_widthc) /2; dst_height/$ dst_width;
 $ POS_Y = ($ SRC_HEIGHT -$src_heightc ) /2;
 }
 MagickCropImage ( $magic_water_handle,$src_widthc,$src_heightc,$pos_x,$pos_y );//Crop
 //Because after the MagickCropImage function, the Gif image changes, but the canvas remains unchanged
 $ this->magick_handle = NewMagickWand();
 MagickNewImage ( $this->magick_handle,$src_widthc,$src_heightc,'#ffffff' );
 MagickSetFormat ( $this->magick_handle,$srcext );
 MagickCompositeImage ( $ this->magick_handle,$magic_water_handle,MW_OverCompositeOp,0,0 );
 //Scale
 MagickScaleImage ( $this->magick_handle, $dst_width, $dst_height );

 }
 //Proportional scaling mode
 if ( $ mode == 2 )
 {
 if ( $src_width/$src_height>$dst_width/$dst_height )
 {
 $dst_height=$dst_width*$src_height/$src_width;
 }
 else
 {
 $dst_width=$dst_height * $src_width/$src_height;
 }
 $this->magick_handle=$magic_water_handle;//Replace
 MagickScaleImage ( $this->magick_handle, $dst_width, $dst_height );//Scale
 }
 //Scale fill mode
 if ( $mode == 3 )
 {
 if ( $src_width/$src_height>$dst_width/$dst_height )
 {
 $dst_heightc=$dst_width*$src_height/$src_width;
 $dst_widthc=$dst_width;
 }
 else
 {
 $dst_widthc=$dst_height*$src_width/$src_height;
 $dst_heightc=$dst_height;
 }
			MagickScaleImage ( $magic_water_handle, $dst_widthc, $dst_heightc );//缩放
			$this->magick_handle = NewMagickWand();
			MagickNewImage ( $this->magick_handle,$dst_width,$dst_height,$this->smallpic_bgcolor );
			MagickSetFormat ( $this->magick_handle,$srcext );
			MagickCompositeImage ( $this->magick_handle,$magic_water_handle,MW_OverCompositeOp, ( $dst_width-$dst_widthc ) /2, ( $dst_height-$dst_heightc ) /2 );
		}
		//打水印
		if ( $this->watermode == 1 )
		{
			$this->set_mark();
		}
		if ( empty ( $dst_file ) )
		{
			//建立临时文件
			$dst_file = tempnam ( $_SERVER["SINASRV_CACHE_DIR"],"TMP_IMG" );
		}
		MagickWriteImage ( $this->magick_handle, $dst_file );
		return $dst_file;
	}

	/**
 * Watermarking
 *
 * @param $src_file The path of the image to be watermarked
 * @param $dst_file The file saving path for producing watermarks. If it is empty, a random temporary file will be produced
 * @return The path of the watermark file/false
*/
	public function water_mark ( $src_file,$dst_file="" )
	{
		$this->magick_handle = NewMagickWand();
		if ( !MagickReadImage ( $this->magick_handle, $src_file ) )
			return false;
		$this->set_mark();
		if ( empty ( $dst_file ) )
		{
			//建立临时文件
			$dst_file = tempnam ( $_SERVER["SINASRV_CACHE_DIR"],"TMP_IMG" );
		}
		MagickWriteImage ( $this->magick_handle, $dst_file );
		return $dst_file;
	}

	/**
 * Internal interface
 * Watermark pictures
 *
*/
	protected  function set_mark()
	{

		//尺寸
		$dst_width = MagickGetImageWidth ( $this->magick_handle );
		$dst_height = MagickGetImageHeight ( $this->magick_handle );
		//处理水印图
		if ( $this->water_mark && is_file ( $this->water_mark ) )
		{
			$magic_water_handle = NewMagickWand();
			MagickRemoveImage ( $magic_water_handle );
			if ( MagickReadImage ( $magic_water_handle, $this->water_mark ) )
			{
				MagickScaleImage ( $magic_water_handle, $dst_width*$this->waterrate, $dst_width*$this->waterrate*MagickGetImageHeight ( $magic_water_handle ) /MagickGetImageWidth ( $magic_water_handle ) );//缩放水印到图片的1/5
				if ( $this->water_mark_pos == 1 )
				{
					$left = $this->padding;
					$top = $this->padding;
				}
				elseif ( $this->water_mark_pos == 2 )
				{
					$left = $dst_width-$this->padding-MagickGetImageWidth ( $magic_water_handle );
					$top = $this->padding;
				}
				elseif ( $this->water_mark_pos == 3 )
				{
					$left = $this->padding;
					$top = $dst_height -$this->padding-MagickGetImageHeight ( $magic_water_handle );
				}
				elseif ( $this->water_mark_pos == 4 )
				{
					$left = $dst_width-$this->padding-MagickGetImageWidth ( $magic_water_handle );
					$top =$dst_height -$this->padding-MagickGetImageHeight ( $magic_water_handle );
				}
				elseif ( $this->water_mark_pos == 5 )
				{
					$left = ( $dst_width-MagickGetImageWidth ( $magic_water_handle ) ) /2;
					$top = ( $dst_height -MagickGetImageHeight ( $magic_water_handle ) ) /2;
				}
				MagickCompositeImage ( $this->magick_handle,$magic_water_handle,MW_OverCompositeOp,$left,$top );
			}
		}
	}
}

PHP