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封装一个PHP的图片处理类
发布时间：2019-12-31 04:00:38编辑：slayer.hover阅读（4298）
用于处理图片缩放，高斯模糊，锐化，图文识别的PHP类.
class ImgTools
{
#图片高斯模糊（适用于png/jpg/gif格式）
public function gaussian_blur(string $source, string $target,int $blurFactor = 1)
{
$gdImageResource = $this->image_create_from_ext($source);
$srcImgObj = $this->blur($gdImageResource, $blurFactor);
$srcinfo = getimagesize($source);
switch ($srcinfo[2]) {
case 1:
imagegif($srcImgObj, $target);
break;
case 2:
imagejpeg($srcImgObj, $target);
break;
case 3:
imagepng($srcImgObj, $target);
break;
default:
return '保存失败'; //保存失败
}
imagedestroy($srcImgObj);
}
private function blur(resource $gdImageResource, int $blurFactor = 1)
{
$blurFactor = round($blurFactor);
$originalWidth = imagesx($gdImageResource);
$originalHeight = imagesy($gdImageResource);
$smallestWidth = ceil($originalWidth * pow(0.5, $blurFactor));
$smallestHeight = ceil($originalHeight * pow(0.5, $blurFactor));
$prevImage = $gdImageResource;
$prevWidth = $originalWidth;
$prevHeight = $originalHeight;
for ($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 = $nextHeight;
}
imagecopyresized($gdImageResource, $nextImage, 0, 0, 0, 0,
$originalWidth, $originalHeight, $nextWidth, $nextHeight);
imagefilter($gdImageResource, IMG_FILTER_GAUSSIAN_BLUR);
imagedestroy($prevImage);
return $gdImageResource;
}
private function image_create_from_ext(string $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;
}
#锐化
public function GDMakeJpegLookLikeCrap(string $source, string $target)
{
$image = imagecreatefromjpeg($source);
$sharpenMatrix = [
[-1, -1, -1],
[-1, -1, -1],
[-1, -1, -1]
];
$divisor = array_sum(array_map('array_sum', $sharpenMatrix));
$offset = 0;
imageconvolution($image, $sharpenMatrix, $divisor, $offset);
imagejpeg($image, $target, 100);
imagedestroy($image);
}
#按比例缩放图片
public function thumb(string $source, string $target, int $des_w, int $des_h)
{
//获取图片的类型
$srcarr = getimagesize($source);
//处理图片创建函数和图片输出函数
switch ($srcarr[2]) {
case 1://gif
$imagecreatefrom = 'imagecreatefromgif';
$imageout = 'imagegif';
break;
case 2://jpg
$imagecreatefrom = 'imagecreatefromjpeg';
$imageout = 'imagejpeg';
break;
case 3://png
$imagecreatefrom = 'imagecreatefrompng';
$imageout = 'imagepng';
break;
}
// 创建原图资源
$src_img = $imagecreatefrom($source);
//获取原图的宽高
$src_w = imagesx($src_img);
$src_h = imagesy($src_img);
// 计算缩放比例（用原图片的宽高分别处以对应目的图片的宽高，选择比例大的作为基准进行缩放）
$scale = ($src_w / $des_w) > ($src_h / $des_h) ? ($src_w / $des_w) : ($src_h / $des_h);
//计算实际缩放时目的图的宽高（向下取整）
$des_w = floor($src_w / $scale);
$des_h = floor($src_h / $scale);
//创建画布
$des_img = imagecreatetruecolor($des_w, $des_h);
//设置缩放起点
$des_x = 0;
$des_y = 0;
$src_x = 0;
$src_y = 0;
//缩放
imagecopyresampled($des_img, $src_img, $des_x, $des_y, $src_x, $src_y, $des_w, $des_h, $src_w, $src_h);
//输出图片
$imageout($des_img, $target);
}
#文本识别调用百度图文识别接口
public function img2txt(string $image): string
{
$code = '';
$access_token = $this->get_ocr_access_token();
$url = 'https://aip.baidubce.com/rest/2.0/ocr/v1/webimage?access_token=' . $access_token;
$headers = ['Content-Type:application/x-www-form-urlencoded'];
$postData = 'image=' . urlencode(base64_encode(file_get_contents($image)));
$data = json_decode(curl_data($url, $postData, false, false, '', $headers), TRUE);
if (!empty($data['words_result'])) {
foreach ($data['words_result'] as $k => $v) {
$code .= $v['words'] . PHP_EOL;
}
}
return $code;
}
private function remember($key, $ttl, callable $func)
{
if (class_exists('redis')) {
$cache = new redis();
$cache->connect('127.0.0.1', '6379');
$cache->select(2);
if ($cache->exists($key)) {
return $cache->get($key);
}
$rows = call_user_func($func);
$cache->set($key, $rows, $ttl);
return $rows;
} else {
return call_user_func($func);
}
}
private function get_ocr_access_token()
{
return $this->remember('ocrToken', 2590000, function () {
$url = 'https://aip.baidubce.com/oauth/2.0/token';
$post_data['grant_type'] = 'client_credentials';
$post_data['client_id'] = 'puD3MMcpW2DM4TInTT84mM3n';
$post_data['client_secret'] = 'SNXEjqnOhmmMjK7XQIX8QQ5zdk4HVwNy';
$res = curl_data($url, $post_data);
$resArr = json_decode($res, TRUE);
return $resArr['access_token'];
});
}
}用法如下：
$source = './images/captcha.jpg'; //源图 $bigger = './images/b_captcha.jpg'; //放大 $blur = './images/m_captcha.jpg'; //模糊 $crap = './images/r_captcha.jpg'; //锐化 $target = './images/t_captcha.jpg'; //目标图 $imgTool = new ImgTools; #放大 $imgTool->thumb($source, $bigger, 600, 300); #模糊 $imgTool->gaussian_blur($bigger, $blur); #锐化 $imgTool->GDMakeJpegLookLikeCrap($blur, $crap); #缩放 $imgTool->thumb($crap, $target, 60, 30); #图文识别 $code = $imgTool->img2txt($target); echo $code;
具体使用场景自己意会~
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