ImageCaptcha.php at 0a360f7 ⋅ terrylinooo/shieldon

<?php
/**
 * This file is part of the Shieldon package.
 *
 * (c) Terry L. <contact@terryl.in>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 * 
 * php version 7.1.0
 * 
 * @category  Web-security
 * @package   Shieldon
 * @author    Terry Lin <contact@terryl.in>
 * @copyright 2019 terrylinooo
 * @license   https://github.com/terrylinooo/shieldon/blob/2.x/LICENSE MIT
 * @link      https://github.com/terrylinooo/shieldon
 * @see       https://shieldon.io
 */

declare(strict_types=1);

namespace Shieldon\Firewall\Captcha;

use RuntimeException;
use Shieldon\Firewall\Captcha\CaptchaProvider;

use function Shieldon\Firewall\get_request;
use function Shieldon\Firewall\get_session_instance;
use function Shieldon\Firewall\unset_superglobal;
use function base64_encode;
use function cos;
use function function_exists;
use function imagecolorallocate;
use function imagecreate;
use function imagecreatetruecolor;
use function imagedestroy;
use function imagefilledrectangle;
use function imagejpeg;
use function imageline;
use function imagepng;
use function imagerectangle;
use function imagestring;
use function mt_rand;
use function ob_end_clean;
use function ob_get_contents;
use function password_hash;
use function password_verify;
use function random_int;
use function sin;
use function strlen;

/**
 * Simple Image Captcha.
 */
class ImageCaptcha extends CaptchaProvider
{
    /**
     * Settings.
     *
     * @var array
     */
    protected $properties = [];


    /**
     * Image type.
     *
     * @var string
     */
    protected $imageType = '';

    /**
     * Word.
     *
     * @var string
     */
    protected $word = '';

    /**
     * Image resource.
     * Throw exception the the value is not resource.
     *
     * @var resource|null|bool
     */
    private $im;

    /**
     * The length of the word.
     *
     * @var int
     */
    protected $length = 4;

    /**
     * Constructor.
     *
     * It will implement default configuration settings here.
     *
     * @param array $config The settings for creating Captcha.
     *
     * @return void
     */
    public function __construct(array $config = [])
    {
        $defaults = [
            'img_width'    => 250,
            'img_height'   => 50,
            'word_length'  => 8,
            'font_spacing' => 10,
            'pool'         => '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
            'colors'       => [
                'background' => [255, 255, 255],
                'border'     => [153, 200, 255],
                'text'       => [51,  153, 255],
                'grid'       => [153, 200, 255]
            ]
        ];

        foreach ($defaults as $k => $v) {
            if (isset($config[$k])) {
                $this->properties[$k] = $config[$k];
            } else {
                $this->properties[$k] = $defaults[$k];
            }
        }

        if (!is_array($this->properties['colors'])) {
            $this->properties['colors'] = $defaults['colors'];
        }

        foreach ($defaults['colors'] as $k => $v) {
            if (!is_array($this->properties['colors'][$k])) {
                $this->properties['colors'][$k] = $defaults['colors'][$k];
            }
        }
    }

    /**
     * Response the result.
     *
     * @return bool
     */
    public function response(): bool
    {
        $postParams = get_request()->getParsedBody();
        $sessionCaptchaHash = get_session_instance()->get('shieldon_image_captcha_hash');

        if (empty($postParams['shieldon_image_captcha']) || empty($sessionCaptchaHash)) {
            return false;
        }

        $flag = false;

        if (password_verify($postParams['shieldon_image_captcha'], $sessionCaptchaHash)) {
            $flag = true;
        }

        // Prevent detecting POST method on RESTful frameworks.
        unset_superglobal('shieldon_image_captcha', 'post');

        return $flag;
    }

    /**
     * Output a required HTML.
     *
     * @return string
     */
    public function form(): string
    {
        // @codeCoverageIgnoreStart
        if (!extension_loaded('gd')) {
            return '';
        }
        // @codeCoverageIgnoreEnd

        $html = '';
        $base64image = $this->createCaptcha();
        $imgWidth = $this->properties['img_width'];
        $imgHeight = $this->properties['img_height'];

        if (!empty($base64image)) {
            $html = '<div style="padding: 0px; overflow: hidden; margin: 10px 0;">';
            $html .= '<div style="
                border: 1px #dddddd solid;
                overflow: hidden;
                border-radius: 3px;
                display: inline-block;
                padding: 5px;
                box-shadow: 0px 0px 4px 1px rgba(0,0,0,0.08);">';
            $html .= '<div style="margin-bottom: 2px;"><img src="data:image/' . $this->imageType . ';base64,' . $base64image . '" style="width: ' . $imgWidth . '; height: ' . $imgHeight . ';"></div>';
            $html .= '<div><input type="text" name="shieldon_image_captcha" style="
                width: 100px;
                border: 1px solid rgba(27,31,35,.2);
                border-radius: 3px;
                background-color: #fafafa;
                font-size: 14px;
                font-weight: bold;
                line-height: 20px;
                box-shadow: inset 0 1px 2px rgba(27,31,35,.075);
                vertical-align: middle;
                padding: 6px 12px;;"></div>';
            $html .= '</div>';
            $html .= '</div>';
        }

        return $html;
    }

    /**
     * Create CAPTCHA
     *
     * @return string
     */
    protected function createCaptcha()
    {
        $imgWidth = $this->properties['img_width'];
        $imgHeight = $this->properties['img_height'];

        $this->createCanvas($imgWidth, $imgHeight);

        $im = $this->getImageResource();

        // Assign colors. 
        $colors = [];

        foreach ($this->properties['colors'] as $k => $v) {

            /**
             * Create color identifier for each color.
             *
             * @var int
             */
            $colors[$k] = imagecolorallocate($im, $v[0], $v[1], $v[2]);
        }

        $this->createRandomWords();

        $this->createBackground(
            $imgWidth,
            $imgHeight, 
            $colors['background']
        );

        $this->createSpiralPattern(
            $imgWidth,
            $imgHeight,
            $colors['grid']
        );

        $this->writeText(
            $imgWidth,
            $imgHeight,
            $colors['text']
        );

        $this->createBorder(
            $imgWidth,
            $imgHeight,
            $colors['border']
        );

        // Save hash to the user sesssion.
        $hash = password_hash($this->word, PASSWORD_BCRYPT);

        get_session_instance()->set('shieldon_image_captcha_hash', $hash);
        get_session_instance()->save();

        return $this->getImageBase64Content();
    }

    /**
     * Prepare the random words that want to display to front.
     *
     * @return void
     */
    private function createRandomWords()
    {
        $this->word = '';

        $poolLength = strlen($this->properties['pool']);
        $randMax = $poolLength - 1;

        for ($i = 0; $i < $this->properties['word_length']; $i++) {
            $this->word .= $this->properties['pool'][random_int(0, $randMax)];
        }

        $this->length = strlen($this->word);
    }

    /**
     * Create a canvas.
     *
     * This method initialize the $im.
     * 
     * @param int $imgWidth  The width of the image.
     * @param int $imgHeight The height of the image.
     *
     * @return void
     */
    private function createCanvas(int $imgWidth, int $imgHeight)
    {
        if (function_exists('imagecreatetruecolor')) {
            $this->im = imagecreatetruecolor($imgWidth, $imgHeight);
    
            // @codeCoverageIgnoreStart

        } else {
            $this->im = imagecreate($imgWidth, $imgHeight);
        }

        // @codeCoverageIgnoreEnd
    }

    /**
     * Create the background.
     * 
     * @param int $imgWidth  The width of the image.
     * @param int $imgHeight The height of the image.
     * @param int $bgColor   The RGB color for the background of the image.
     *
     * @return void
     */
    private function createBackground(int $imgWidth, int $imgHeight, $bgColor)
    {
        $im = $this->getImageResource();

        imagefilledrectangle($im, 0, 0, $imgWidth, $imgHeight, $bgColor);
    }

    /**
     * Create a spiral patten.
     *
     * @param int $imgWidth  The width of the image.
     * @param int $imgHeight The height of the image.
     * @param int $gridColor The RGB color for the gri of the image.
     *
     * @return void
     */
    private function createSpiralPattern(int $imgWidth, int $imgHeight, $gridColor)
    {
        $im = $this->getImageResource();

        // Determine angle and position.
        $angle = ($this->length >= 6) ? mt_rand(-($this->length - 6), ($this->length - 6)) : 0;
        $xAxis = mt_rand(6, (360 / $this->length) - 16);
        $yAxis = ($angle >= 0) ? mt_rand($imgHeight, $imgWidth) : mt_rand(6, $imgHeight);

        // Create the spiral pattern.
        $theta   = 1;
        $thetac  = 7;
        $radius  = 16;
        $circles = 20;
        $points  = 32;

        for ($i = 0, $cp = ($circles * $points) - 1; $i < $cp; $i++) {
            $theta += $thetac;
            $rad = $radius * ($i / $points);

            $x = (int) (($rad * cos($theta)) + $xAxis);
            $y = (int) (($rad * sin($theta)) + $yAxis);

            $theta += $thetac;
            $rad1 = $radius * (($i + 1) / $points);

            $x1 = (int) (($rad1 * cos($theta)) + $xAxis);
            $y1 = (int) (($rad1 * sin($theta)) + $yAxis);

            imageline($im, $x, $y, $x1, $y1, $gridColor);
            $theta -= $thetac;
        }  
    }

    /**
     * Write the text into the image canvas.
     *
     * @param int $imgWidth  The width of the image.
     * @param int $imgHeight The height of the image.
     * @param int $textColor The RGB color for the grid of the image.
     *
     * @return void
     */
    private function writeText(int $imgWidth, int $imgHeight, $textColor)
    {
        $im = $this->getImageResource();

        $z = (int) ($imgWidth / ($this->length / 3));
        $x = mt_rand(0, $z);
        // $y = 0;

        for ($i = 0; $i < $this->length; $i++) {
            $y = mt_rand(0, $imgHeight / 2);
            imagestring($im, 5, $x, $y, $this->word[$i], $textColor);
            $x += ($this->properties['font_spacing'] * 2);
        }
    }

    /**
     * Write the text into the image canvas.
     *
     * @param int $imgWidth    The width of the image.
     * @param int $imgHeight   The height of the image.
     * @param int $borderColor The RGB color for the border of the image.
     *
     * @return void
     */
    private function createBorder(int $imgWidth, int $imgHeight, $borderColor): void
    {
        $im = $this->getImageResource();

        // Create the border.
        imagerectangle($im, 0, 0, $imgWidth - 1, $imgHeight - 1, $borderColor);
    }

    /**
     * Get the base64 string of the image.
     *
     * @return string
     */
    private function getImageBase64Content(): string
    {
        $im = $this->getImageResource();

        // Generate image in base64 string.
        ob_start();

        if (function_exists('imagejpeg')) {
            $this->imageType = 'jpeg';
            imagejpeg($im);

            // @codeCoverageIgnoreStart

        } elseif (function_exists('imagepng')) {
            $this->imageType = 'png';
            imagepng($im);
        } else {
            echo '';
        }

        // @codeCoverageIgnoreEnd

        $imageContent = ob_get_contents();
        ob_end_clean();
        imagedestroy($im);

        return base64_encode($imageContent);
    }

    /**
     * Get image resource.
     *
     * @return resource
     */
    private function getImageResource()
    {
        if (!is_resource($this->im)) {

            // @codeCoverageIgnoreStart
            throw new RuntimeException(
                'Cannot create image resource.'
            );
            // @codeCoverageIgnoreEnd
        }

        return $this->im;
    }
}

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1		<?php
2		/**
3		* This file is part of the Shieldon package.
4		*
5		* (c) Terry L. <contact@terryl.in>
6		*
7		* For the full copyright and license information, please view the LICENSE
8		* file that was distributed with this source code.
9		*
10		* php version 7.1.0
11		*
12		* @category Web-security
13		* @package Shieldon
14		* @author Terry Lin <contact@terryl.in>
15		* @copyright 2019 terrylinooo
16		* @license https://github.com/terrylinooo/shieldon/blob/2.x/LICENSE MIT
17		* @link https://github.com/terrylinooo/shieldon
18		* @see https://shieldon.io
19		*/
20
21		declare(strict_types=1);
22
23		namespace Shieldon\Firewall\Captcha;
24
25		use RuntimeException;
26		use Shieldon\Firewall\Captcha\CaptchaProvider;
27
28		use function Shieldon\Firewall\get_request;
29		use function Shieldon\Firewall\get_session_instance;
30		use function Shieldon\Firewall\unset_superglobal;
31		use function base64_encode;
32		use function cos;
33		use function function_exists;
34		use function imagecolorallocate;
35		use function imagecreate;
36		use function imagecreatetruecolor;
37		use function imagedestroy;
38		use function imagefilledrectangle;
39		use function imagejpeg;
40		use function imageline;
41		use function imagepng;
42		use function imagerectangle;
43		use function imagestring;
44		use function mt_rand;
45		use function ob_end_clean;
46		use function ob_get_contents;
47		use function password_hash;
48		use function password_verify;
49		use function random_int;
50		use function sin;
51		use function strlen;
52
53		/**
54		* Simple Image Captcha.
55		*/
56		class ImageCaptcha extends CaptchaProvider
57		{
58		/**
59		* Settings.
60		*
61		* @var array
62		*/
63		protected $properties = [];
64
65
66		/**
67		* Image type.
68		*
69		* @var string
70		*/
71		protected $imageType = '';
72
73		/**
74		* Word.
75		*
76		* @var string
77		*/
78		protected $word = '';
79
80		/**
81		* Image resource.
82		* Throw exception the the value is not resource.
83		*
84		* @var resource\|null\|bool
85		*/
86		private $im;
87
88		/**
89		* The length of the word.
90		*
91		* @var int
92		*/
93		protected $length = 4;
94
95		/**
96		* Constructor.
97		*
98		* It will implement default configuration settings here.
99		*
100		* @param array $config The settings for creating Captcha.
101		*
102		* @return void
103		*/
104	3	public function __construct(array $config = [])
105		{
106		$defaults = [
107	3	'img_width' => 250,
108		'img_height' => 50,
109		'word_length' => 8,
110		'font_spacing' => 10,
111		'pool' => '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
112		'colors' => [
113		'background' => [255, 255, 255],
114		'border' => [153, 200, 255],
115		'text' => [51, 153, 255],
116		'grid' => [153, 200, 255]
117		]
118		];
119
120	3	foreach ($defaults as $k => $v) {
121	3	if (isset($config[$k])) {
122	3	$this->properties[$k] = $config[$k];
123		} else {
124	3	$this->properties[$k] = $defaults[$k];
125		}
126		}
127
128	3	if (!is_array($this->properties['colors'])) {
129	3	$this->properties['colors'] = $defaults['colors'];
130		}
131
132	3	foreach ($defaults['colors'] as $k => $v) {
133	3	if (!is_array($this->properties['colors'][$k])) {
134	3	$this->properties['colors'][$k] = $defaults['colors'][$k];
135		}
136		}
137		}
138
139		/**
140		* Response the result.
141		*
142		* @return bool
143		*/
144	3	public function response(): bool
145		{
146	3	$postParams = get_request()->getParsedBody();
147	3	$sessionCaptchaHash = get_session_instance()->get('shieldon_image_captcha_hash');
148
149	3	if (empty($postParams['shieldon_image_captcha']) \|\| empty($sessionCaptchaHash)) {
150	3	return false;
151		}
152
153	3	$flag = false;
154
155	3	if (password_verify($postParams['shieldon_image_captcha'], $sessionCaptchaHash)) {
156	3	$flag = true;
157		}
158
159		// Prevent detecting POST method on RESTful frameworks.
160	3	unset_superglobal('shieldon_image_captcha', 'post');
161
162	3	return $flag;
163		}
164
165		/**
166		* Output a required HTML.
167		*
168		* @return string
169		*/
170	3	public function form(): string
171		{
172		// @codeCoverageIgnoreStart
173		if (!extension_loaded('gd')) {
174		return '';
175		}
176		// @codeCoverageIgnoreEnd
177
178	3	$html = '';
179	3	$base64image = $this->createCaptcha();
180	3	$imgWidth = $this->properties['img_width'];
181	3	$imgHeight = $this->properties['img_height'];
182
183	3	if (!empty($base64image)) {
184	3	$html = '<div style="padding: 0px; overflow: hidden; margin: 10px 0;">';
185	3	$html .= '<div style="
186		border: 1px #dddddd solid;
187		overflow: hidden;
188		border-radius: 3px;
189		display: inline-block;
190		padding: 5px;
191		box-shadow: 0px 0px 4px 1px rgba(0,0,0,0.08);">';
192	3	$html .= '<div style="margin-bottom: 2px;"><img src="data:image/' . $this->imageType . ';base64,' . $base64image . '" style="width: ' . $imgWidth . '; height: ' . $imgHeight . ';"></div>';
193	3	$html .= '<div><input type="text" name="shieldon_image_captcha" style="
194		width: 100px;
195		border: 1px solid rgba(27,31,35,.2);
196		border-radius: 3px;
197		background-color: #fafafa;
198		font-size: 14px;
199		font-weight: bold;
200		line-height: 20px;
201		box-shadow: inset 0 1px 2px rgba(27,31,35,.075);
202		vertical-align: middle;
203		padding: 6px 12px;;"></div>';
204	3	$html .= '</div>';
205	3	$html .= '</div>';
206		}
207
208	3	return $html;
209		}
210
211		/**
212		* Create CAPTCHA
213		*
214		* @return string
215		*/
216	3	protected function createCaptcha()
217		{
218	3	$imgWidth = $this->properties['img_width'];
219	3	$imgHeight = $this->properties['img_height'];
220
221	3	$this->createCanvas($imgWidth, $imgHeight);
222
223	3	$im = $this->getImageResource();
224
225		// Assign colors.
226	3	$colors = [];
227
228	3	foreach ($this->properties['colors'] as $k => $v) {
229
230		/**
231		* Create color identifier for each color.
232		*
233		* @var int
234		*/
235	3	$colors[$k] = imagecolorallocate($im, $v[0], $v[1], $v[2]);
236		}
237
238	3	$this->createRandomWords();
239
240	3	$this->createBackground(
241	3	$imgWidth,
242	2	$imgHeight,
243	3	$colors['background']
244		);
245
246	3	$this->createSpiralPattern(
247	3	$imgWidth,
248	2	$imgHeight,
249	3	$colors['grid']
250		);
251
252	3	$this->writeText(
253	3	$imgWidth,
254	2	$imgHeight,
255	3	$colors['text']
256		);
257
258	3	$this->createBorder(
259	3	$imgWidth,
260	2	$imgHeight,
261	3	$colors['border']
262		);
263
264		// Save hash to the user sesssion.
265	3	$hash = password_hash($this->word, PASSWORD_BCRYPT);
266
267	3	get_session_instance()->set('shieldon_image_captcha_hash', $hash);
268	3	get_session_instance()->save();
269
270	3	return $this->getImageBase64Content();
271		}
272
273		/**
274		* Prepare the random words that want to display to front.
275		*
276		* @return void
277		*/
278	3	private function createRandomWords()
279		{
280	3	$this->word = '';
281
282	3	$poolLength = strlen($this->properties['pool']);
283	3	$randMax = $poolLength - 1;
284
285	3	for ($i = 0; $i < $this->properties['word_length']; $i++) {
286	3	$this->word .= $this->properties['pool'][random_int(0, $randMax)];
287		}
288
289	3	$this->length = strlen($this->word);
290		}
291
292		/**
293		* Create a canvas.
294		*
295		* This method initialize the $im.
296		*
297		* @param int $imgWidth The width of the image.
298		* @param int $imgHeight The height of the image.
299		*
300		* @return void
301		*/
302	3	private function createCanvas(int $imgWidth, int $imgHeight)
303		{
304	3	if (function_exists('imagecreatetruecolor')) {
305	3	$this->im = imagecreatetruecolor($imgWidth, $imgHeight);
306
307		// @codeCoverageIgnoreStart
308
309		} else {
310		$this->im = imagecreate($imgWidth, $imgHeight);
311		}
312
313		// @codeCoverageIgnoreEnd
314		}
315
316		/**
317		* Create the background.
318		*
319		* @param int $imgWidth The width of the image.
320		* @param int $imgHeight The height of the image.
321		* @param int $bgColor The RGB color for the background of the image.
322		*
323		* @return void
324		*/
325	3	private function createBackground(int $imgWidth, int $imgHeight, $bgColor)
326		{
327	3	$im = $this->getImageResource();
328
329	3	imagefilledrectangle($im, 0, 0, $imgWidth, $imgHeight, $bgColor);
330		}
331
332		/**
333		* Create a spiral patten.
334		*
335		* @param int $imgWidth The width of the image.
336		* @param int $imgHeight The height of the image.
337		* @param int $gridColor The RGB color for the gri of the image.
338		*
339		* @return void
340		*/
341	3	private function createSpiralPattern(int $imgWidth, int $imgHeight, $gridColor)
342		{
343	3	$im = $this->getImageResource();
344
345		// Determine angle and position.
346	3	$angle = ($this->length >= 6) ? mt_rand(-($this->length - 6), ($this->length - 6)) : 0;
347	3	$xAxis = mt_rand(6, (360 / $this->length) - 16);
348	3	$yAxis = ($angle >= 0) ? mt_rand($imgHeight, $imgWidth) : mt_rand(6, $imgHeight);
349
350		// Create the spiral pattern.
351	3	$theta = 1;
352	3	$thetac = 7;
353	3	$radius = 16;
354	3	$circles = 20;
355	3	$points = 32;
356
357	3	for ($i = 0, $cp = ($circles * $points) - 1; $i < $cp; $i++) {
358	3	$theta += $thetac;
359	3	$rad = $radius * ($i / $points);
360
361	3	$x = (int) (($rad * cos($theta)) + $xAxis);
362	3	$y = (int) (($rad * sin($theta)) + $yAxis);
363
364	3	$theta += $thetac;
365	3	$rad1 = $radius * (($i + 1) / $points);
366
367	3	$x1 = (int) (($rad1 * cos($theta)) + $xAxis);
368	3	$y1 = (int) (($rad1 * sin($theta)) + $yAxis);
369
370	3	imageline($im, $x, $y, $x1, $y1, $gridColor);
371	3	$theta -= $thetac;
372		}
373		}
374
375		/**
376		* Write the text into the image canvas.
377		*
378		* @param int $imgWidth The width of the image.
379		* @param int $imgHeight The height of the image.
380		* @param int $textColor The RGB color for the grid of the image.
381		*
382		* @return void
383		*/
384	3	private function writeText(int $imgWidth, int $imgHeight, $textColor)
385		{
386	3	$im = $this->getImageResource();
387
388	3	$z = (int) ($imgWidth / ($this->length / 3));
389	3	$x = mt_rand(0, $z);
390		// $y = 0;
391
392	3	for ($i = 0; $i < $this->length; $i++) {
393	3	$y = mt_rand(0, $imgHeight / 2);
394	3	imagestring($im, 5, $x, $y, $this->word[$i], $textColor);
395	3	$x += ($this->properties['font_spacing'] * 2);
396		}
397		}
398
399		/**
400		* Write the text into the image canvas.
401		*
402		* @param int $imgWidth The width of the image.
403		* @param int $imgHeight The height of the image.
404		* @param int $borderColor The RGB color for the border of the image.
405		*
406		* @return void
407		*/
408	3	private function createBorder(int $imgWidth, int $imgHeight, $borderColor): void
409		{
410	3	$im = $this->getImageResource();
411
412		// Create the border.
413	3	imagerectangle($im, 0, 0, $imgWidth - 1, $imgHeight - 1, $borderColor);
414		}
415
416		/**
417		* Get the base64 string of the image.
418		*
419		* @return string
420		*/
421	3	private function getImageBase64Content(): string
422		{
423	3	$im = $this->getImageResource();
424
425		// Generate image in base64 string.
426	3	ob_start();
427
428	3	if (function_exists('imagejpeg')) {
429	3	$this->imageType = 'jpeg';
430	3	imagejpeg($im);
431
432		// @codeCoverageIgnoreStart
433
434		} elseif (function_exists('imagepng')) {
435		$this->imageType = 'png';
436		imagepng($im);
437		} else {
438		echo '';
439		}
440
441		// @codeCoverageIgnoreEnd
442
443	3	$imageContent = ob_get_contents();
444	3	ob_end_clean();
445	3	imagedestroy($im);
446
447	3	return base64_encode($imageContent);
448		}
449
450		/**
451		* Get image resource.
452		*
453		* @return resource
454		*/
455	3	private function getImageResource()
456		{
457	3	if (!is_resource($this->im)) {
458
459		// @codeCoverageIgnoreStart
460		throw new RuntimeException(
461		'Cannot create image resource.'
462		);
463		// @codeCoverageIgnoreEnd
464		}
465
466	3	return $this->im;
467		}
468		}