Craft\ImageResizerService::getSettingForAssetSource PHP Method

    public function getSettingForAssetSource($sourceId, $setting)
    {
        $settings = $this->getPlugin()->getSettings();
        $globalSetting = $settings->{$setting};
        if (isset($settings->assetSourceSettings[$sourceId])) {
            if ($settings->assetSourceSettings[$sourceId][$setting]) {
                return $settings->assetSourceSettings[$sourceId][$setting];
            }
        }
        return $globalSetting;
    }