Browse Prior Art Database

Digital Character Encoding

IP.com Disclosure Number: IPCOM000074007D
Original Publication Date: 1971-Mar-01
Included in the Prior Art Database: 2005-Feb-23
Document File: 3 page(s) / 45K

Publishing Venue

IBM

Related People

Grant, DE: AUTHOR

Abstract

Recent developments in photoprinting have utilized cathode-ray tubes as character generators. For such cathode-ray tube character generator it is necessary to encode a character into a digital matrix. The digital matrix information is then utilized by the cathode-ray tube to generate the character. The process for digitally encoding characters is shown by the flow diagram.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Digital Character Encoding

Recent developments in photoprinting have utilized cathode-ray tubes as character generators. For such cathode-ray tube character generator it is necessary to encode a character into a digital matrix. The digital matrix information is then utilized by the cathode-ray tube to generate the character. The process for digitally encoding characters is shown by the flow diagram.

The process begins with a photographic enlargement 10 of the character to be digitized. The enlargement is processed through an analog digitization operation 12 that determines incremental values for the Y-dimension of the character associated with incremental values for the X-dimension of the character. The record of the X-Y coordinates is stored by the digitizer on magnetic tape 14.

The tape is then read into a computer programmed to simulate the character in an X-Y grid matrix. The program 15 generates matrix patterns in the core storage of the computer. Another routine in the program converts the character matrix pattern into the compressed code commands required by the photoprinter. If no editing is required, the computer 15 will generate photoprinter code cards which may eventually be used with photoprinter 16A to generate the characters. If editing is required, a different routine in the computer program produces digital tape 18 that drives the photoprinter 16B to produce a photodigital intermediate 20 for editing.

The photodigital intermediate is, in fact, an enlargement of the character similar to enlargement 10 of the character, except that each black element in the enlargement 20 is a single large dot. Thus, each dot in the photodigital intermediate corresponds to a black bit. The appearance of this dot pattern gives a visual impression of the shape and proportions of the digitized character.

The editing of the photodigital intermediate 20 is done by...