A practical voiceband television system design.

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Authors
Mackenzie, Franklin Forsthove
Subjects
voiceband television
Advisors
Cooper, Paul E.
Date of Issue
1973-09
Date
September 1973
Publisher
Monterey, California. Naval Postgraduate School
Language
en_US
Abstract
A need exists to send television on channels of limited bandwidth, particularly 3 kHz. Successive images must have adequate picture content yet be frequent enough to give the appearance of motion. A new coding scheme was devised to meet this need for video data compression. A 2400 baud system was designed and built. A hierarchy of transmission modes is used which allows the transmitter to choose the most efficient of 3 modes to send a line. One mode uses a variable-length Instantaneously Uniquely Decipherable code optimized for the statistics of some typical expected pictures. The picture size is 64 by 64 elements, each with 4 luminance levels. The transmitter has a stored line (129 bits) and a two-dimension model to predict the following line. After comparing the prediction to a fresh line the deviations from the prediction are sent. Then the receiver uses the same model to update a similar stored line to be displayed. Frame duration can range from .13 to 3.54 seconds as determined by the actual picture.
Type
Thesis
Description
Series/Report No
Department
Electrical Engineering
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Funder
Format
Citation
Distribution Statement
Approved for public release; distribution is unlimited.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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