The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 01, 1997
Filed:
Apr. 09, 1992
John E Bruder, Arlington, MA (US);
PictureTel Corporation, Andover, MA (US);
Abstract
A method and apparatus for selecting blocks for intraframe encoding in a way which avoids intraframe encoding blocks which have not diverged. An inter-energy value is calculated which represents the approximate number of bits required to encode the block of data using a best interframe encoding technique. An intra-energy value is calculated which represents the approximate number of bits required to encode the block of data using intraframe encoding. The block is transmitted using intraframe encoding if the intra-energy is approximately less than the inter-energy. Otherwise, the block is either a) transmitted using an interframe encoding technique or b) not transmitted, thereby implying that the block from the previous frame in the sequence should be repeated. An encoder determines the number of times K that the block has been interframe encoded since it was last intraframe encoded. A weighting factor w(K) is calculated which decreases with the value of K. A weighted energy value is then calculated by multiplying the intra-energy plus an offset S by the weighting factor w(k). If the weighted energy value is approximately less than the inter-energy value, the block is transmitted using intraframe encoding.