Joomla 3 thumbnails function

image.php

/**
   * Method to create thumbnails from the current image and save them to disk. It allows creation by resizing
	 * or croppping the original image.
	 *
	 * @param   mixed    $thumbSizes      string or array of strings. Example: $thumbSizes = array('150x75','250x150');
	 * @param   integer  $creationMethod  1-3 resize $scaleMethod | 4 create croppping
	 * @param   string   $thumbsFolder    destination thumbs folder. null generates a thumbs folder in the image folder
	 *
	 * @return array
	 *
	 * @throws  LogicException
	 * @throws  InvalidArgumentException
	 *
	 * @since 12.2
	 */
	public function createThumbs($thumbSizes, $creationMethod = self::SCALE_INSIDE, $thumbsFolder = null)
	{
		// Make sure the resource handle is valid.
		if (!$this->isLoaded())
		{
			throw new LogicException('No valid image was loaded.');
		}

		// No thumbFolder set -> we will create a thumbs folder in the current image folder
		if (is_null($thumbsFolder))
		{
			$thumbsFolder = dirname($this->getPath()) . '/thumbs';
		}

		// Check destination
		if (!is_dir($thumbsFolder) && (!is_dir(dirname($thumbsFolder)) || !@mkdir($thumbsFolder)))
		{
			throw new InvalidArgumentException('Folder does not exist and cannot be created: ' . $thumbsFolder);
		}

		// Process thumbs
		$thumbsCreated = array();

		if ($thumbs = $this->generateThumbs($thumbSizes, $creationMethod))
		{
			// Parent image properties
			$imgProperties = self::getImageFileProperties($this->getPath());

			foreach ($thumbs as $thumb)
			{
				// Get thumb properties
				$thumbWidth 	= $thumb->getWidth();
				$thumbHeight 	= $thumb->getHeight();

				// Generate thumb name
				$filename 		= pathinfo($this->getPath(), PATHINFO_FILENAME);
				$fileExtension 	= pathinfo($this->getPath(), PATHINFO_EXTENSION);
				$thumbFileName 	= $filename . '_' . $thumbWidth . 'x' . $thumbHeight . '.' . $fileExtension;

				// Save thumb file to disk
				$thumbFileName = $thumbsFolder . '/' . $thumbFileName;

				if ($thumb->toFile($thumbFileName, $imgProperties->type))
				{
					// Return JImage object with thumb path to ease further manipulation
					$thumb->path = $thumbFileName;
					$thumbsCreated[] = $thumb;
				}
			}
		}
		return $thumbsCreated;
	}