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PHP中实现图片的锐化
2020-03-10 49人围观 0条评论
简介PHP中实现图片的锐化

      

      //读取图像的类型

      //1 = GIF, 2 = JPG, 3 = PNG, 4 = SWF, 5 = PSD, 6 = BMP, 7 = TIFF(intel byte order), 8 = TIFF(motorola byte order), 9 = JPC, 10 = JP2, 11 = JPX, 12 = JB2, 13 = SWC, 14 = IFF

      function GetImageType($filename) {return (($imginfo=@getimagesize($filename))!=null ? $imginfo[2] : null);}   

      //图像锐化

      //$scr_im:图像资源句柄,$degree:锐化度数

      function Sharp(&$src_im, &$dst_im, $degree)

      {

       $src_x = imagesx($src_im);

       $src_y = imagesy($src_im);

       //$dst_im = imagecreate($src_x, $src_y);

       //imagecopy($dst_im, $src_im, 0, 0, 0, 0, $src_x, $src_y);

       $cnt = 0;

       for ($x=1; $x<$src_x; $x++)

       for ($y=1; $y<$src_y; $y++)

       {

       $src_clr1 = imagecolorsforindex($src_im, imagecolorat($src_im, $x-1, $y-1));

       $src_clr2 = imagecolorsforindex($src_im, imagecolorat($src_im, $x, $y));

       $r = intval($src_clr2["red"]+$degree*($src_clr2["red"]-$src_clr1["red"]));

       $g = intval($src_clr2["green"]+$degree*($src_clr2["green"]-$src_clr1["green"]));

       $b = intval($src_clr2["blue"]+$degree*($src_clr2["blue"]-$src_clr1["blue"]));

       $r = min(255, max($r, 0));

       $g = min(255, max($g, 0));

       $b = min(255, max($b, 0));

       //echo "r:$r, g:$g, b:$b";

       if (($dst_clr=imagecolorexact($dst_im, $r, $g, $b))==-1)

       $dst_clr = Imagecolorallocate($dst_im, $r, $g, $b);

       $cnt++;

       if ($dst_clr==-1) die("color allocate faile at $x, $y ($cnt).");

       imagesetpixel($dst_im, $x, $y, $dst_clr);

       }

       return $dst_im;

      }   

      $ImageFunctions = array("imagecreatefromwbmp", "imagecreatefromgif", "imagecreatefromjpeg", "imagecreatefrompng");  

      if (!empty($_POST["ImageName"]))

      { 

       set_time_limit(10*60);

       if (($ImageType=GetImageType($_POST["ImageName"]))==false)

       die("指定文件不存在或不是有效的图片或不支持类型!");

       if ($ImageType==6) $ImageType = 0;

       if ($ImageType>3) die("不支持的图片类型!");

       $im1 = $ImageFunctions[$ImageType]($_POST["ImageName"]);

       $im2 = $ImageFunctions[$ImageType]($_POST["ImageName"]);

       //print_r(imagecolorsforindex($im, imagecolorat($im, 10, 10)));

       Sharp($im1, $im2, $_POST["Degree"]);

       header("Content-type: image/png");

       imagepng($im2);

       imagedestroy($im1);

       imagedestroy($im2);

      } 

      ?>

      

      请输入图片的本地路径或URL:

      " size=32>

      锐化度数(例:0.6、3.0):

      ">

      

       

       改了一下,省了一个$im:  

       function Sharp2(&$im, $degree)

      {

       $cnt = 0;

       for ($x=imagesx($im)-1; $x>0; $x--)

       for ($y=imagesy($im)-1; $y>0; $y--)

       {

       $clr1 = imagecolorsforindex($im, imagecolorat($im, $x-1, $y-1));

       $clr2 = imagecolorsforindex($im, imagecolorat($im, $x, $y));

       $r = intval($clr2["red"]+$degree*($clr2["red"]-$clr1["red"]));

       $g = intval($clr2["green"]+$degree*($clr2["green"]-$clr1["green"]));

       $b = intval($clr2["blue"]+$degree*($clr2["blue"]-$clr1["blue"]));

       $r = min(255, max($r, 0));

       $g = min(255, max($g, 0));

       $b = min(255, max($b, 0));

       //echo "r:$r, g:$g, b:$b
    ";

       if (($new_clr=imagecolorexact($im, $r, $g, $b))==-1)

       $new_clr = Imagecolorallocate($im, $r, $g, $b);

       $cnt++;

       if ($new_clr==-1) die("color allocate faile at $x, $y ($cnt).");

       imagesetpixel($im, $x, $y, $new_clr);

       }

      }   

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