PHP生成海报（解决png图片背景变黑问题）

控制器代码：使用的字体参考：链接：https://pan.baidu.com/s/1cejrtDTQq7YmJ84ZtX3xRg 
提取码：phpp

 public function poster(){
           $config = array(
            'text'=>array(
                array(
                    'text'=> "幸福就在身边",
                    'left'=>182,
                    'top'=>105,
                    'fontPath'=>realpath('assets/fonts/SourceHanSansK-Regular.ttf'), //如果不显示汉字可能是字体不支持或路径不对
                    'fontSize'=>20,             //字号
                    'fontColor'=>'255,255,255',       //字体颜色
                    'angle'=>0,
                )
            ),
            'image'=>array(
                array(
                    'url'=>'uploads/mincode/2022120116044947456.jpg',       //图片资源路径
                    'left'=>130,
                    'top'=>-140,
                    'stream'=>0,            //图片资源是否是字符串图像流
                    'right'=>0,
                    'bottom'=>0,
                    'width'=>100,
                    'height'=>100,
                    'opacity'=>100
                ),
                array(
                    'url'=>'xxccj/img/avatar.png',
                    'left'=>120,
                    'top'=>850,
                    'right'=>0,
                    'stream'=>0,
                    'bottom'=>150,
                    'width'=>55,
                    'height'=>55,
                    'opacity'=>100
                ),
            ),
            'background'=>'xxccj/img/poster.jpg',
        );
        $imgfile = createPoster($config,"po.jpg");
        echo "";

    }

createposter:

/**
 * 生成宣传海报
 * @param array  参数,包括图片和文字
 * @param string  $filename 生成海报文件名,不传此参数则不生成文件,直接输出图片
 * @return [type] [description]
 */
function createPoster($config=array(),$filename=""){
    //如果要看报什么错，可以先注释调这个header
    if(empty($filename)) header("content-type: image/png");
    $imageDefault = array(
        'left'=>0,
        'top'=>0,
        'right'=>0,
        'bottom'=>0,
        'width'=>100,
        'height'=>100,
        'opacity'=>100
    );
    $textDefault = array(
        'text'=>'',
        'left'=>0,
        'top'=>0,
        'fontSize'=>32,       //字号
        'fontColor'=>'255,255,255', //字体颜色
        'angle'=>0,
    );
    $background = $config['background'];//海报最底层得背景
    //背景方法
    $backgroundInfo = getimagesize($background);
    $backgroundFun = 'imagecreatefrom'.image_type_to_extension($backgroundInfo[2], false);
    $background = $backgroundFun($background);
    $backgroundWidth = imagesx($background);  //背景宽度
    $backgroundHeight = imagesy($background);  //背景高度
    $imageRes = imageCreatetruecolor($backgroundWidth,$backgroundHeight);
    $color = imagecolorallocate($imageRes, 0, 0, 0);
    imagefill($imageRes, 0, 0, $color);
    // imageColorTransparent($imageRes, $color);  //颜色透明
    imagecopyresampled($imageRes,$background,0,0,0,0,imagesx($background),imagesy($background),imagesx($background),imagesy($background));
    //处理了图片
    if(!empty($config['image'])){
        foreach ($config['image'] as $key => $val) {
            $val = array_merge($imageDefault,$val);
            $info = getimagesize($val['url']);
            $function = 'imagecreatefrom'.image_type_to_extension($info[2], false);
            if($val['stream']){   //如果传的是字符串图像流
                $info = getimagesizefromstring($val['url']);
                $function = 'imagecreatefromstring';
            }
            $res = $function($val['url']);
            $resWidth = $info[0];
            $resHeight = $info[1];
            //建立画板 ，缩放图片至指定尺寸
            $canvas=imagecreatetruecolor($val['width'], $val['height']);
            $colors = imagecolorallocatealpha($canvas, 255, 255, 255,127);
            imagefill($canvas, 0, 0, $colors);
            //关键函数，参数（目标资源，源，目标资源的开始坐标x,y, 源资源的开始坐标x,y,目标资源的宽高w,h,源资源的宽高w,h）
            imagecopyresampled($canvas, $res, 0, 0, 0, 0, $val['width'], $val['height'],$resWidth,$resHeight);
            $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']) - $val['width']:$val['left'];
            $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']) - $val['height']:$val['top'];
            //放置图像
            imagecopy($imageRes,$canvas, $val['left'],$val['top'],0,0,$val['width'],$val['height']);//左，上，右，下，宽度，高度，透明度
        }
    }
    //处理文字
    if(!empty($config['text'])){
        foreach ($config['text'] as $key => $val) {
            $val = array_merge($textDefault,$val);
            list($R,$G,$B) = explode(',', $val['fontColor']);
            $fontColor = imagecolorallocate($imageRes, $R, $G, $B);
            $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']):$val['left'];
            $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']):$val['top'];
            imagettftext($imageRes,$val['fontSize'],$val['angle'],$val['left'],$val['top'],$fontColor,$val['fontPath'],$val['text']);
        }
    }
    //生成图片
    if(!empty($filename)){
        $res = imagejpeg ($imageRes,$filename,90); //保存到本地
        imagedestroy($imageRes);
        if(!$res) return false;
        return $filename;
    }else{
        imagejpeg ($imageRes);     //在浏览器上显示
        imagedestroy($imageRes);
    }
}