使用ImageMagick PHP库进行图像编辑

Question

我正在开发图像编辑器，我成功地在位置x，y上的图像上写文字，现在我需要在被称为白色的图像上绘制白色图像。白色图像将绘制在位置线X，线Y和图像宽度，高度的动态大小。我写代码，但我没有得到图像的右坐标和高度宽度。 这是我的图像渲染功能。

 $image = new Imagick('image.jpg');

    $diagnose=$this->input->post('diagnoses');  
    $fontsize=$this->input->post('fontsize');
    $fontstyle=$this->input->post('fontstyle');

        $cordX   = $this->input->post('posX'); 
        $cordY   = $this->input->post('posY');

        $font_size = 20;
        // Watermark text
        //$diagnose = "Hello world.{newline}It's a beautiful day.";


        $textlinesArray = explode("{newline}",$diagnose);

        // Create a new drawing palette
        $draw = new ImagickDraw();

        // Set font properties
        $draw->setFont('Arial');
        $draw->setFontSize($font_size);
        $draw->setFillColor('black');

        // Position text at the bottom-right of the image
        $draw->setGravity(Imagick::GRAVITY_NORTHWEST);

        $i = 0;
        foreach ($textlinesArray as $index => $text) {   
             $newY = ($i * $font_size)  + $cordY;
             //echo $newY . "</br>";
             //echo $text;
             // Draw text on the image
             $image->annotateImage($draw,  $cordX, $newY,0, $text);
             $i++;

        }

        $draw->setFillColor('magenta');    // Set up some colors to use for fill and outline
        $draw->setStrokeColor( new ImagickPixel( 'cyan' ) );
        $draw->setStrokeWidth(2);
        $draw->rectangle($cordX, $cordY, 200, 300);    // Draw the rectangle 

        $image->drawImage( $draw );

        // Set output image format
        $image->setImageFormat('png');

        // Output the new image
        header('Content-type: image/png');
        echo $image;

这里是输出，我需要颜色框动态宽度高度和位置