Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

A 4-PIXEL CODE COMPRESSOR

IP.com Disclosure Number: IPCOM000024449D
Original Publication Date: 1980-Aug-31
Included in the Prior Art Database: 2004-Apr-02
Document File: 2 page(s) / 67K

Publishing Venue

Xerox Disclosure Journal

Abstract

The above rules apply where there is a maximum of 63 all-zero nibbles before the terminating nibble. If there are 64 or more all-zero nibbles before a non-zero terminating nibble, the data string is converted into a first part comprising a number of sets of 64 all-zero nibbles and second part comprising the remaining 0 to 63 all-zero nibbles and the terminating nibble. The first part is encoded into a type 3B output word of the form 1lnnnnnnOOOO where nnnnnn is the binary repre-sentation of the number of sets of 64 all-zero nibbles. The second set is then encoded according to the previously described rules.

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 84% of the total text.

Page 1 of 2

XEROX DISCLOSURE JOURNAL

A 4-PIXEL CODE COMPRESSOR 358/261 C1. U.S. Proposed Henry Liao Classification

Int. C1. H04n 1/00

CODE ASSIGNMENT TABLE

CODE TYPE

Type 1

ASS IG NM EN T

?7 /i = oo+x = 1000

= 01+ = 0100 = 10+ =OOlO = 11+ =0001

# # = 00 4 RAW(raw image data)

= 01 -$ NOL(norma1 end of line) = 10 4 PBK(prediction break)
= 11 + RPTkepeat previous line)

01 1 I0000 -3 optional SOP(start of page) 01 110001 + optional EOP(end of page)

# # = oo+ x = 1000

= 01- = 0100 = lo+ = 0010 = llj = 0001

nnnnn -3 5 bits representation of Y

z=O-*Y=O, z=1+ Y=l

bbbb = exact bit pattern of class B terminator except the following: X = 0011*+ bbbb = 0100

bbbb = class A or class B terminator

nnnnnn = binary representation of Y

nnnnnn = multiple of 64 zero nibbles

lm

X&euroA, Y = 0

control codes

Type 2

Type 3

-1

2A

3Al 3A2

38

X6B

Y = 0,l

[ 11 nnnnnn bbbb 1

XEA, 26<Y(63

2B

2c

-- X&euro B, 2< -- Y(63

I I

64xN,l< -- N(63

Volume 5 Number 4 July/August 1980

Figure 1A

451

[This page contains 1 picture or other non-text object]

Page 2 of 2

A 4-PIXEL CODE COMPRESSOR (Cont'd)

The above rules apply where there is a maximum of 63 all-zero nibbles before the terminating nibble. If there are 64 or more all-zero nibbles before a non-zero terminating nibble, the data string is converted into a first part comprising a number of sets of 64 all-zero nibbles and second part comprising the remaining 0 to 63 all-zero nibbles and the terminating nibble. The first part is encoded into a type 3B output word of the form...