if ($this->lastOutput !== null) {

private function getProgressInfo()
{
        //This will return null everytime.
	if ($this->remaining === null) {
		return null;
	}

	return array(
		'percent'   => $this->percent,
		'remaining' => $this->remaining,
		'rate'      => $this->rate
	);
}

private function parseProgress($progress)
{
	if (!$this->initialized) {
		$this->initialize();
	}
	
	if (null === $this->totalSize || null === $this->duration) {
		return;
	}
	$matches = array();

	if (preg_match($this->getPattern(), $progress, $matches) !== 1) {
		return null;
	}

	$currentDuration = $this->convertDuration($matches[2]);
	$currentTime = microtime(true);
	$currentSize = trim(str_replace('kb', '', strtolower(($matches[1]))));
	$percent = max(0, min(1, $currentDuration / $this->duration));
	$this->lastOutput = $currentTime;
	
	$delta = $currentTime - $this->lastOutput;

	// Check the type of the currentSize variable and convert it to an integer if needed.
	if(!is_numeric($currentSize)) {
		$currentSize = (int)$currentSize;
	}

	$deltaSize = $currentSize - $this->currentSize;
	$rate = $deltaSize * $delta;
	if ($rate > 0) {
		$totalDuration = $this->totalSize / $rate;
		$this->remaining = floor($totalDuration - ($totalDuration * $percent));
		$this->rate = floor($rate);
	} else {
		$this->remaining = 0;
		$this->rate = 0;
	}

	$percent = $percent / $this->totalPass + ($this->currentPass - 1) / $this->totalPass;

	$this->percent = floor($percent * 100);
	$this->currentSize = (int) $currentSize;
	$this->currentTime = $currentDuration;
	
	return $this->getProgressInfo();
}