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:
Nov. 11, 2003
Filed:
May. 17, 1999
Hiroaki Ueda, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A frame receiving unit calculates the number of a frame to be compressed and gets an image data from the frame. A frame checking unit checks the type of the frame and allocates required code memory. When the frame is an I frame, a frequency conversion unit converts the image to a spatial frequency, a quantization unit quantizes the spatial frequency, and a variable-length coding unit performs variable-length coding. At the same time, a reverse quantization unit performs reverse-quantization and a reverse frequency conversion unit performs reverse-conversion to create a reference image. When the frame is a P frame, a motion search unit searches for a motion of the image. The frequency conversion unit converts a difference between the image and the reference image to the spatial frequency, the quantization unit performs quantization, and the variable-length coding unit performs variable-length coding. At the same time, the reverse quantization unit performs reverse-quantization, the reverse frequency conversion unit performs reverse frequency conversion to return the reverse conversion result to the difference of the images, and a motion compensation unit combines the result with a motion-compensated reference image. When the frame is a B frame, a code indicating that the frame is the same as the reference frame is generated. The generated code is output to the allocated code memory.