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Conversion of Bit Density

IP.com Disclosure Number: IPCOM000042785D
Original Publication Date: 1984-Jun-01
Included in the Prior Art Database: 2005-Feb-04
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Fujisawa, H: AUTHOR [+3]

Abstract

This article describes a conversion of a font pattern of a 16 x 32-dot matrix for a 203-pel (picture element) image process to a 24 x 48-dot matrix for a 300-pel image process (Fig. 1). The font pattern fetched from the 203-pel font memory 2 is used to access pattern extension tables 3a and 3b, and the bit patterns fetched from both pattern extension tables 3a and 3b are assembled to complete the 24 x 48-dot pattern. Character boxes of the dot matrix for 203 pels and 300 pels are shown in Fig. 1. To make the 300-pel box, 16 dots in the horizontal direction are increased to 24 dots and 32 dots in the vertical direction are increased to 48 dots. Character codes stored in register 1 (Fig. 2) are sequentially applied to 203-pel font memory 2, which stores font patterns of 16 x 32 dots for the 203 pels.

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Conversion of Bit Density

This article describes a conversion of a font pattern of a 16 x 32-dot matrix for a 203-pel (picture element) image process to a 24 x 48-dot matrix for a 300-pel image process (Fig. 1). The font pattern fetched from the 203-pel font memory 2 is used to access pattern extension tables 3a and 3b, and the bit patterns fetched from both pattern extension tables 3a and 3b are assembled to complete the 24 x 48-dot pattern. Character boxes of the dot matrix for 203 pels and 300 pels are shown in Fig. 1. To make the 300-pel box, 16 dots in the horizontal direction are increased to 24 dots and 32 dots in the vertical direction are increased to 48 dots. Character codes stored in register 1 (Fig. 2) are sequentially applied to 203- pel font memory 2, which stores font patterns of 16 x 32 dots for the 203 pels. The left 8 bits (PL) are applied to pattern extension table 3a, and the right 8 bits (PR) are applied to pattern extension table 3b. The table 3a stores 16-bit patterns which have the same data content as that of the left 8-bit patterns PL, and the table 3b stores 16-bit patterns which have the same data content as that of the right 8-bit patterns PR. The right 4 bits of the table 3a and the left 4 bits of the table 3b have all 0s. The 16 bits of the table 3a are supplied to register 4a, and the 16 bits of the table 3b are supplied to register 4b. The left 8 bits of the register 4a are stored in positions 5a of image buffer 5, and the right 8...