Fatal error: Call to undefined function curl_init()

I get this error at the end of cron execution after transcoding took place :

Fatal error: Call to undefined function curl_init() in /var/www/sites/mysubdomainpath/modules/storage_api/storage_api.module on line 1429

I don't know if this is related but the video was only available for play back after a second attempt by using the Retranscode this video option.