/**
     * 将pdf文件转化为多张png图片
     * @param string $pdf  pdf所在路径 （/www/pdf/abc.pdf pdf所在的绝对路径）
     * @param string $path 新生成图片所在路径 (/www/pngs/)
     *
     * @return array|bool
     */
    function pdf2png($pdf, $path)
    {
        if (!extension_loaded(‘imagick‘)) {
            return false;
        }
        if (!file_exists($pdf)) {
            return false;
        }
        $im = new \Imagick();
        $im->setResolution(120, 120); //设置分辨率 值越大分辨率越高
        $im->setCompressionQuality(100);
        $im->readImage($pdf);
        foreach ($im as $k => $v) {
            $v->setImageFormat(‘png‘);
            $fileName = $path . md5($k . time()) . ‘.png‘;
            if ($v->writeImage($fileName) == true) {
                $return[] = $fileName;
            }
        }
        return $return;
    }

    /**
     * 将pdf转化为单一png图片
     * @param string $pdf  pdf所在路径 （/www/pdf/abc.pdf pdf所在的绝对路径）
     * @param string $path 新生成图片所在路径 (/www/pngs/)
     *
     * @throws Exception
     */
    function pdf2png2($pdf, $path)
    {
        try {
            $im = new \Imagick();
            $im->setCompressionQuality(100);
            $im->setResolution(120, 120);//设置分辨率 值越大分辨率越高
            $im->readImage($pdf);

            $canvas = new \Imagick();
            $imgNum = $im->getNumberImages();
            //$canvas->setResolution(120, 120);
            $old_height = 0;
            foreach ($im as $k => $sub) {
                $sub->setImageFormat(‘png‘);
                //$sub->setResolution(120, 120);
                $sub->stripImage();
                $sub->trimImage(0);
                $width  = $sub->getImageWidth() + 10;
                $height = $sub->getImageHeight() + 10;
                if ($k + 1 == $imgNum) {
                    //最后一页空白高度处理
                    $height = $old_height;
                }else{
                    $old_height = $height;
                }
                $canvas->newImage($width, $height, new \ImagickPixel(‘white‘));
                $canvas->compositeImage($sub, \Imagick::COMPOSITE_DEFAULT, 5, 5);
            }

            $canvas->resetIterator();
            $canvas->appendImages(true)->writeImage($path . microtime(true) . ‘.png‘);
        } catch (Exception $e) {
            throw $e;
        }
    }