Call to undefined method Imagick

php7, ImageMagick-7.0.8-3 生成圆形图片 会出现这个错误

Call to undefined method Imagick::roundCorners

ImageMagick-6 生成圆形图片

$image = new Imagick('45_y.png');

$image->setImageFormat('png');

$image->roundCorners($image->getImageWidth() / 2, $image->getImageHeight() / 2);

$image->writeImage( '45_y1.png' );  //保存图片

$image->destroy();

ImageMagick-7.0.8-3  生成圆形图片 需要换种思路

$width = ‘300’;

$height = '300';

$cornerRadius = $long/2;

$image = new Imagick('45_y.png');

$image->setImageFormat('png');

$image->thumbnailImage($width,$height);

$mask = new Imagick();

$mask->newImage($width, $height, new ImagickPixel('transparent'), 'png');

// create the rounded rectangle

$shape = new ImagickDraw();

$shape->setFillColor(new ImagickPixel('black'));

$shape->roundRectangle(0, 0, $width-1, $height-1, $cornerRadius, $cornerRadius);

// draw the rectangle

$mask->drawImage($shape);

// apply mask

$image->compositeImage($mask, Imagick::COMPOSITE_DSTIN, 0, 0);

$mask->writeImage(  '45_y1.png' );