Patent ID: 8155206

Claim:
A coding method comprising: coding an input picture to obtain a coded picture signal; decoding the coded picture signal to obtain a decoded picture; determining whether the decoded picture is a reference picture or a non-reference picture; judging, if the decoded picture is determined to be a non-reference picture, whether or not the decoded non-reference picture can be displayed prior to one or more decoded pictures stored in a decoded picture buffer; and storing the decoded non-reference picture in the decoded picture buffer without outputting the decoded non-reference picture prior to any decoded picture stored in the decoded picture buffer which is to be outputted before the decoded non-reference picture, if the decoded non-reference picture cannot be displayed prior to one or more decoded pictures stored in the decoded picture buffer which have not been displayed, storing the decoded picture in the decoded picture buffer if the decoded picture is determined to be a reference picture, wherein said storing of the decoded reference picture and said storing of the decoded non-reference picture that cannot be displayed prior to one or more decoded pictures stored in the decoded picture buffer comprises, if the decoded picture buffer does not have an empty space for another decoded picture, finding an area of the decoded picture buffer in which a decoded picture is stored with an earliest display order and not to be used for reference after said decoding of the non-reference picture to overwrite the another decoded picture onto the decoded picture stored in the decoded picture buffer with an earliest display order and not to be used for reference after said decoding of the non-reference picture.