Patent · US Expired

Video coder

USRE34824E · kind E · reissue

7Cited by
10References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 13, 1993
Grant dateJan 10, 1995
Priority date
Expiry dateJan 13, 2013

Classification

  • Technology area (CPC —)General

Abstract

A coder assembles bursts of blocks of image data (e.g. transform coded coefficients) and associated overhead data into a sequence of data which are then transmitted. Both the transform coded coefficients and the overhead data are initially stored in separate FIFO memory stores (21), (22). The blocks of transform coded coefficients have a `last coefficient` flag accompanying the last coefficient, and the overhead information contains a unique word SWITCH, after the header information but before the `end-of-block` flag. The `last coefficient` flag and the SWITCH word are recognized by a toggle controller (29) which controls the reading of the stores so that the coefficient data and overhead data are selectively passed to a buffer (30) in a desired sequence. The buffer (30) is followed by a variable length coder (31) which supplies the output of the coder at a constant bit rate. Provision (34-38) is made to calculate the quantity of output data represented at any time by the contents of the buffer and the result is used to control the rate of generation of image data.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.