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US5046122A Expired / Lapsed US ⏱️ 0.0 years remaining

Image compression device

Assignee: Fujifilm Holdings Corp
•
Filing: 1989-12-28
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Granted: 1991-09-03
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Expires: 2009-12-28
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Abstract

Abstract This invention is an image compression device which includes a means to rearrange binary image data in a unit of pixel in accordance with a first conversion table, and a means to encode said rearranged data in accordance with a second conversion table, and which is characterized in that the second conversion table contains a data comprising a code which is added to a predetermined code used for the case where the same logical value continues in the rearranged data and which is based on the number of continuous pixels, a code having the same bit at the leading edge thereof as the leading bit of the predetermined code for the case where the same logical value continues up to the trailing end of the rearranged data, and a code having at its leading edge of a bit different from the leading bit of the predetermined code which is to be used for the data other than above. The above device according to this invention can compress any binary data including line images and dot images at high efficiency and high speed.

Inventors

  • 👤 Daisuke Nakaya
  • 👤 Hiroshi Horikawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 18:17
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/41; H04N1/4105

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 251 words
An image compression device for compressing binary image data, said binary image data having corresponding address information and being formed by data received from a plurality of pixels, wherein each bit of said binary image data corresponds to an individual one of said pixels, comprising: means to rearrange said binary image data in accordance with at least a first conversion table; and means to encode said rearranged data in accordance with a second conversion table, wherein said second conversion table contains data comprising a first code, said first code being predetermined for each possible logical bit value; a second code, said second code being determined according to a count of an uninterrupted series of the same logical bit value; and a third code, said third code being determined in accordance with a unit of said rearranged data having an uninterrupted series of the same logical bit value, where the leading edge bit of said third code differs from the leading edge bit of said first code; and wherein upon the occurrence of a first situation, said first situation being when the same logical bit value continues in an uninterrupted series in said rearranged data said encoding means adds in series said second code to said third code thus creating a combined code, said encoding means encodes said combined code in place of said uninterrupted series, and upon the occurrence of a second situation, said second situation being when said first situation does not occur, said encoding means encodes said first code.
Claim 2
Dependent Claim 251 words
An image compression device for compressing binary image data, said binary image data having corresponding address information and being formed by data received from a plurality of pixels, wherein each bit of said binary image data corresponds to an individual one of said pixels, comprising: means to rearrange said binary image data in accordance with at least a first conversion table; and means to encode said rearranged data in accordance with a second conversion table, wherein said second conversion table contains data comprising a first code, said first code being predetermined for each possible logical bit value; a second code, said second code being determined according to a count of an uninterrupted series of the same logical bit value; and a third code, said third code being determined in accordance with a unit of said rearranged data having an uninterrupted series of the same logical bit value, where the leading edge bit of said third code differs from the leading edge bit of said first code; and wherein upon the occurrence of a first situation, said first situation being when the same logical bit value continues in an uninterrupted series in said rearranged data said encoding means adds in series said second code to said third code thus creating a combined code, said encoding means encodes said combined code in place of said uninterrupted series, and upon the occurrence of a second situation, said second situation being when said first situation does not occur, said encoding means encodes said first code.
Claim 3
Dependent Claim 37 words
An image compression device as claimed in claim 1, wherein said image compression device processes said binary image data in units of sub-blocks, said sub-blocks being formed by a predetermined number bits of said binary image data.
Claim 4
Dependent Claim 82 words
An image compression device as claimed in claim 2, wherein said data contained in said second conversion table further comprises a predetermined fourth code, said fourth code being predetermined for each possible logical bit value and the leading edge bit of said fourth code being different from the leading edge bit of said first code; and wherein when said first situation occurs at the trailing end of said sub-block, said encoding means encodes said fourth code in place of said uninterrupted series.
Claim 5
Dependent Claim 56 words
An image compression device as claimed in claim 1, wherein said third code comprises a single bit, said single bit being different than the leading edge bit of said first code; and wherein said encoding means adds said third code to the leading edge of said unit of said rearranged data not having an uninterrupted series.
Claim 6
Dependent Claim 28 words
An image compression device as claimed in claim 1, wherein said first conversion table contains data which position adjacent pixels of said binary image data side by side.
Claim 7
Dependent Claim 87 words
An image compression device as claimed in claim 1, wherein said rearrangement means comprises an address generator which outputs a first address for reading out one said sub-block of said binary image data, a sub-block address generator which outputs a second address along a threshold matrix, an address conversion table which outputs address data for the output data from said first conversion table in accordance with the data from said second address and from an external unit, and a rearrangement circuit sequencer which controls said respective means.
Claim 8
Dependent Claim 19 words
An image compression device as claimed in claim 6, wherein said sub-block is in the unit of 4 bits.
Claim 9
Dependent Claim 22 words
An image compression device as claimed in claim 1, wherein intermediate buffers are provided between said rearrangement means and said encoding means.
Claim 10
Dependent Claim 97 words
An image compression device as claimed in claim 8, wherein said encoding means comprises an address generator which outputs an address for reading out the data from said intermediate buffers, an encoding circuit sequencer which converts in bit the data read out from said intermediate buffers and controls the data as a whole, a selector which selectively outputs the output from said second conversion table and the address from said address generator, and a bit compaction circuit which compresses the data outputted from said selector in a unit of bit length generated from the encoding circuit sequencer.
Claim 11
Dependent Claim 28 words
An image compression device as claimed in claim 9, wherein said encoding circuit contains microprograms, each of said microprograms corresponding to a different type of binary image data.

References Cited (Backward Citations)

US3624637A Cited
US3902008A Cited
US4301479A Cited
US4757552A Cited
US4626829A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-09-02 1995-03-04 1995-09-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-09-02 1999-03-04 1999-09-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-09-02 2003-03-04 2003-09-03 $7700.00 Window Closed / Lapsed

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