Try to get in the habit of checking documentation, it will save you much grief
http://php.net/manual/en/function.curl-setopt.php
CURLOPT_ENCODING The contents of the "Accept-Encoding: " header. This enables decoding of the response. Supported encodings are “identity”, “deflate”, and “gzip”. If an empty string, “”, is set, a header containing all supported encoding types is sent.
vs.
curl_setopt($ch, CURLOPT_ENCODING, 1);