core-bundle/src/Resources/contao/library/Contao/Image.php
public function getCacheName()
	{
		$importantPart = $this->getImportantPart();

		$strCacheKey = substr(md5
		(
			  '-w' . $this->getTargetWidth()
			. '-h' . $this->getTargetHeight()
			. '-o' . $this->getOriginalPath()
			. '-m' . $this->getResizeMode()
			. '-z' . $this->getZoomLevel()
			. '-x' . $importantPart['x']
			. '-y' . $importantPart['y']
			. '-i' . $importantPart['width']
			. '-e' . $importantPart['height']
			. '-t' . $this->fileObj->mtime
		), 0, 8);

		return StringUtil::stripRootDir(System::getContainer()->getParameter('contao.image.target_dir')) . '/' . substr($strCacheKey, -1) . '/' . $this->fileObj->filename . '-' . $strCacheKey . '.' . $this->fileObj->extension;
	}
public function getCacheName()
	{
		$importantPart = $this->getImportantPart();

		$strCacheKey = substr(md5
		(
			  '-w' . $this->getTargetWidth()
			. '-h' . $this->getTargetHeight()
			. '-o' . $this->getOriginalPath()
			. '-m' . $this->getResizeMode()
			. '-z' . $this->getZoomLevel()
			. '-x' . $importantPart['x']
			. '-y' . $importantPart['y']
			. '-i' . $importantPart['width']
			. '-e' . $importantPart['height']
			. '-t' . $this->fileObj->mtime
		), 0, 8);

		return StringUtil::stripRootDir(System::getContainer()->getParameter('contao.image.target_dir')) . '/' . substr($strCacheKey, -1) . '/' . $this->fileObj->filename . '-' . $strCacheKey . '.' . $this->fileObj->extension;
	}
Get the cache name

@return string The cache name