@fc_lamp

/**
 * 修正（旋转图像）
 *  @param  $imgPath 图像路径
 *  @param $degrees   旋转角度
 *  @internal
 *  @author fc_lamp
 */
function correctImageAngle($imgPath,$degrees=False)
{
	$ext = '';
	if($degrees===False)
	{
		//则直接看图像是否倒置了，
		if(!function_exists('exif_read_data'))
		{
			//exif_read_data 能获取图像中所有exif信息
			//需要 php_mbstring.dll  php_exif.dll 扩展，且php_exif.dll依赖于mbstring
			return False;	
		}
		
		//获取exif信息中的Orientation参数
		$exif = exif_read_data ($imgPath, 0, true );
		if($exif===False)
		{
			return False;
		}
		$orientation=0;
		foreach ( $exif as $key => $section )
		{
			foreach ( $section as $name => $val )
			{
				if($name=='MimeType')
				{
					$ext = explode('/',$val);
					$ext = end($ext);
				}
				//echo "$key.$name: $val<br />\n";
				if($name=='Orientation')
				{
					$orientation = $val;
					break;
			   }
			}
		}		
	
		if($orientation==3)
		{
			$degrees=180;
		
		}elseif($orientation==6)
		{
			$degrees = 270;
		
		}elseif($orientation==8)
		{
			$degrees=90;
		}else{
			
			$degrees =0;
		}
	}

	
	//旋转图像
	$imgSaveFun = $imgModel = NULL;
	if(empty($ext))
	{
		$ext = explode('.',$imgPath);
		$ext = end($ext);
	}
	$ext = strtolower($ext);
	switch ($ext)
	{
		case 'png':
			$imgModel = imagecreatefrompng($imgPath);
			$imgSaveFun = 'imagepng';
			break;
		case 'gif':
			$imgModel = imagecreatefromgif($imgPath);
			$imgSaveFun = 'imagegif';
			break;
		case 'wbmp':
			$imgModel = imagecreatefromwbmp($imgPath);
			$imgSaveFun='imagewbmp';
			break;
		default:
			$imgModel = imagecreatefromjpeg($imgPath);
			$imgSaveFun='imagejpeg';
	}
	
	$rotate = imagerotate($imgModel, $degrees, 0);
	
	// Output
	$imgSaveFun($rotate,$imgPath);
	return True;
}