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:
Mar. 10, 1998
Filed:
Nov. 22, 1995
James N Maertens, Sunnyvale, CA (US);
Mitsubishi Semiconductor America, Inc., Durham, NC (US);
Abstract
A high bit rate start code monitoring, searching and detecting circuit includes a Least Significant Bit (LSB) zero counter, a Most Significant Bit (MSB) zero counter, first and second adders, first and second registers, a comparator, a start code detector, and a start code decoder. The LSB zero counter counts the number of consecutive zero bits from the least significant bit while the MSB zero counter counts the number of consecutive zero bits starting with the most significant bit. A LSB zero count output is added with a prescribed value by the first adder to arrive at a Zero.sub.-- Bits.sub.-- Shifted.sub.-- Out (ZBSO) value, which is saved in the first register. A MSB zero count output is added with the stored value of the ZBSO value during the subsequent clock cycle. If the summed (S) value is greater than or equal to 23, then the start code detector is enabled. The start code detector can detect parts of a start code contained in two separate bitstreams or a start code embedded in a bitstream. When enabled by a signal from the start code detector, the start code decoder analyzes the upper 8 bits of the bitstream to output the corresponding start signal to identify a MPEG layer to a central processing unit or a variable length decoder prior to decoding of the encoded bitstream data.