Home>Article>Backend Development> An example of how to generate blurry images using PHP
This article mainly introduces the method of generating blurred pictures in PHP, involving the implementation techniques of PHP Gaussian algorithm to realize the picture blur function. Friends in need can refer to it
The example of this article tells the implementation of generating blurred pictures in PHP Methods. Share it with everyone for your reference, the details are as follows:
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(); $image_blur->gaussian_blur("./1.jpg",null,null,3); ?>
Original image effect:
Generate blur The effect after the picture:
How to use PHP two-dimensional array to remove duplicate items
How to use Thinkphp5 behavior Summary
The above is the detailed content of An example of how to generate blurry images using PHP. For more information, please follow other related articles on the PHP Chinese website!