Model/Product/Image.php
public function getForceLossyUrl()
    {
        $baseFile = $this->getBaseFile();
        $extension = pathinfo($baseFile, PATHINFO_EXTENSION); // @codingStandardsIgnoreLine
        $url = $this->getBaseFileUrl($baseFile);
        if ($extension == 'png' || $extension == 'bmp') {
            if ($this->isFastlyImageOptimizationEnabled() == false) {
                $this->lossyUrl = $url . '?format=jpeg';
            } else {
                $this->lossyParam = '&format=jpeg';
            }
        }
    }
public function getForceLossyUrl()
    {
        $baseFile = $this->getBaseFile();
        $extension = pathinfo($baseFile, PATHINFO_EXTENSION); // @codingStandardsIgnoreLine
        $url = $this->getBaseFileUrl($baseFile);
        if ($extension == 'png' || $extension == 'bmp') {
            if ($this->isFastlyImageOptimizationEnabled() == false) {
                $this->lossyUrl = $url . '?format=jpeg';
            } else {
                $this->lossyParam = '&format=jpeg';
            }
        }
    }
Creates a force lossy url param or url + param depending if IO is disabled or enabled