imagecreate - PHP code example

Using the PHP Function Imagecreate() to Create, Edit, and Modify Images

PHP is not just for creating web pages, it can do a lot more, one of which is manipulate images. It has the ability to do this through its GD library, which stands for Graphic Draw. In this article, we will look at a few of the basic functions that can be used to create, edit, and modify images. We will also look at some of the functions that can be used to write text and draw lines on your image.

To start, we will look at the function imagecreate(). This function creates a virtual image of the given size and returns it. This image can be either a JPG, GIF or PNG file. You can also use this function to create an image from a string, which must be base64 encoded first using the function base64_decode().

Another useful function is the imagerotate() function, which allows you to rotate an existing image. It takes the angle of rotation as its argument and then rotates the image accordingly. This can be useful for displaying your images on a different angle, or simply making the image more aesthetically pleasing.

Finally, we will look at the imagecolorallocate() function, which sets a specific color for a particular pixel in a virtual image. This is especially useful if you need to set a specific color for an element such as the background of your image, or a colour to be written on with text or drawn with a line.

imagecreate example

  public function image($destination, $min_resolution, $max_resolution) {
    $extension = pathinfo($destination, PATHINFO_EXTENSION);
    $min = explode('x', $min_resolution);
    $max = explode('x', $max_resolution);

    $width = rand((int) $min[0], (int) $max[0]);
    $height = rand((int) $min[1], (int) $max[1]);

    // Make an image split into 4 sections with random colors.     $im = imagecreate($width, $height);
    for ($n = 0; $n < 4; $n++) {
      $color = imagecolorallocate($im, rand(0, 255), rand(0, 255), rand(0, 255));
      $x = $width / 2 * ($n % 2);
      $y = $height / 2 * (int) ($n >= 2);
      imagefilledrectangle($im, (int) $x, (int) $y, (int) ($x + $width / 2), (int) ($y + $height / 2), $color);
    }

    // Make a perfect circle in the image middle.     $color = imagecolorallocate($im, rand(0, 255), rand(0, 255), rand(0, 255));
    $smaller_dimension = min($width, $height);
    imageellipse($im, (int) ($width / 2), (int) ($height / 2), $smaller_dimension, $smaller_dimension, $color);

public function generate(int $length = 7): BasicCaptchaImage
    {
        $code = $this->createCaptchaCode($length);

        $filesystem = new Filesystem();

        if ($filesystem->exists($this->backgroundPath)) {
            /** @var \GdImage $img */
            $img = imagecreatefrompng($this->backgroundPath);
        } else {
            /** @var \GdImage $img */
            $img = imagecreate(self::FALLBACK_WIDTH_IMAGE, self::FALLBACK_HEIGHT_IMAGE);
            imagecolorallocate($img, 255, 255, 255);
        }

        $codeColor = (int) imagecolorallocate($img, 0, 0, 0);
        if ($filesystem->exists($this->fontPath)) {
            imagettftext($img, 45, 0, 80, 55, $codeColor, $this->fontPath, $code);
        } else {
            imagestring($img, 5, 100, 20, $code, $codeColor);
        }

        ob_start();

/** @var \Drupal\Core\Render\RendererInterface $renderer */
    $renderer = $this->container->get('renderer');

    $png = File::create([
      'uri' => 'public://test-image.png',
    ]);
    $png->save();

    // We need to create an actual empty PNG, or the GD toolkit will not     // consider the image valid.     $png_resource = imagecreate(300, 300);
    imagefill($png_resource, 0, 0, imagecolorallocate($png_resource, 0, 0, 0));
    imagepng($png_resource, $png->getFileUri());

    $svg = File::create([
      'uri' => 'public://test-image.svg',
    ]);
    $svg->save();
    // We don't have to put any real SVG data in here, because the GD toolkit     // won't be able to load it anyway.     touch($svg->getFileUri());

        $stm = Shopware()->Db()->query($sql, [$mailing, $email]);

        if ($stm->rowCount()) {
            $sql = 'UPDATE s_campaigns_mailings SET `read`=`read`+1 WHERE id=?';
            Shopware()->Db()->query($sql, [$mailing]);
        }

        $this->Response()->headers->set('content-type', 'image/gif');
        $image = imagecreate(1, 1);
        if ($image === false) {
            return;
        }
        $white = (int) imagecolorallocate($image, 255, 255, 255);
        imagefill($image, 1, 1, $white);
        imagegif($image);
        imagedestroy($image);
    }

    /** * @deprecated in 5.6, will be private in 5.8 * * Init mailing method * * Initializes the mailing using the mailing id. * * @param int|null $mailingID * * @return array|null */