the encoded region having been encoded as a skipped region, if the error measure is less than a specified threshold value; otherwise, {HEAD ~ the encoded region} having been encoded as {TAIL ~ the temporary encoded region} 
encoded as
the encoded region having been encoded as a skipped region , if the error measure is less than a specified threshold value ; otherwise , { HEAD ~ the encoded region } having been encoded as { TAIL ~ the temporary encoded region }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL