php实现图片高斯模糊的方法 PHP生成模糊图片的代码
在php中可以通过高斯算法实现图片的模糊，其实现的语句是“function gaussian_blur($srcImg,$savepath=null...$blurFactor=3){...}”，其中blurFactor的值代表模糊程度。
图片对比
正常图片
模糊后的图片
<?php
class image_blur{
/**
* 图片高斯模糊（适用于png/jpg/gif格式）
* @param $srcImg 原图片
* @param $savepath 保存路径
* @param $savename 保存名字
* @param $positon 模糊程度
*
*基于Martijn Frazer代码的扩充， 感谢 Martijn Frazer
*/
public function gaussian_blur($srcImg,$savepath=null,$savename=null,$blurFactor=3){
$gdImageResource=$this->image_create_from_ext($srcImg);
$srcImgObj=$this->blur($gdImageResource,$blurFactor);
$temp = pathinfo($srcImg);
$name = $temp['basename'];
$path = $temp['dirname'];
$exte = $temp['extension'];
$savename = $savename ? $savename : $name;
$savepath = $savepath ? $savepath : $path;
$savefile = $savepath .'/'. $savename;
$srcinfo = @getimagesize($srcImg);
switch ($srcinfo[2]) {
case 1: imagegif($srcImgObj, $savefile); break;
case 2: imagejpeg($srcImgObj, $savefile); break;
case 3: imagepng($srcImgObj, $savefile); break;
default: return '保存失败'; //保存失败
}
return $savefile;
imagedestroy($srcImgObj);
}
/**
* Strong Blur
*
* @param $gdImageResource 图片资源
* @param $blurFactor 可选择的模糊程度
* 可选择的模糊程度 0使用 3默认 超过5时 极其模糊
* @return GD image 图片资源类型
* @author Martijn Frazer, idea based on http://stackoverflow.com/a/20264482
*/
private function blur($gdImageResource, $blurFactor = 3)
{
// blurFactor has to be an integer
$blurFactor = round($blurFactor);
$originalWidth = imagesx($gdImageResource);
$originalHeight = imagesy($gdImageResource);
$smallestWidth = ceil($originalWidth * pow(0.5, $blurFactor));
$smallestHeight = ceil($originalHeight * pow(0.5, $blurFactor));
// for the first run, the previous image is the original input
$prevImage = $gdImageResource;
$prevWidth = $originalWidth;
$prevHeight = $originalHeight;
// scale way down and gradually scale back up, blurring all the way
for($i = 0; $i < $blurFactor; $i += 1)
{
// determine dimensions of next image
$nextWidth = $smallestWidth * pow(2, $i);
$nextHeight = $smallestHeight * pow(2, $i);
// resize previous image to next size
$nextImage = imagecreatetruecolor($nextWidth, $nextHeight);
imagecopyresized($nextImage, $prevImage, 0, 0, 0, 0,
$nextWidth, $nextHeight, $prevWidth, $prevHeight);
// apply blur filter
imagefilter($nextImage, IMG_FILTER_GAUSSIAN_BLUR);
// now the new image becomes the previous image for the next step
$prevImage = $nextImage;
$prevWidth = $nextWidth;
$prevHeight = $nextHeight;
}
// scale back to original size and blur one more time
imagecopyresized($gdImageResource, $nextImage,
0, 0, 0, 0, $originalWidth, $originalHeight, $nextWidth, $nextHeight);
imagefilter($gdImageResource, IMG_FILTER_GAUSSIAN_BLUR);
// clean up
imagedestroy($prevImage);
// return result
return $gdImageResource;
}
private function image_create_from_ext($imgfile)
{
$info = getimagesize($imgfile);
$im = null;
switch ($info[2]) {
case 1: $im=imagecreatefromgif($imgfile); break;
case 2: $im=imagecreatefromjpeg($imgfile); break;
case 3: $im=imagecreatefrompng($imgfile); break;
}
return $im;
}
}
$image_blur = new image_blur();
echo $image_blur->gaussian_blur("5.jpg","D:\phpstudy_pro\WWW\cs.com\gs","6.jpg",6);
?>
