Browse Prior Art Database

Black and White Graphics Transmission

IP.com Disclosure Number: IPCOM000090183D
Original Publication Date: 1969-Feb-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Stucki, P: AUTHOR

Abstract

Data compression by a factor of two can be achieved through transmission of only every second sample of a high-resolution, about 1000 samples/line, TV scanner for black and white graphics, such as drawings and typewritten messages, having a limb thickness of at least twice the spatial distance of the sampling raster. Samples from alternate lines are displaced by a sampling distance unit.

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Black and White Graphics Transmission

Data compression by a factor of two can be achieved through transmission of only every second sample of a high-resolution, about 1000 samples/line, TV scanner for black and white graphics, such as drawings and typewritten messages, having a limb thickness of at least twice the spatial distance of the sampling raster. Samples from alternate lines are displaced by a sampling distance unit.

The receiver is programmed so as to add part of the suppressed information in accordance with these three patterns.

(Image Omitted)

While the hardware implementation of pattern 1 is conventional, the implementation of patterns 2 and 3 requires employing a delay line able to store information for one line length sampling time. A digital glass memory can be used for this purpose.

This method lends itself to multiplexing two scanners with the full bandwidth of the transmission channel maintained.

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