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US5319724A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and method for compressing still images

Assignee: Ricoh Co Ltd
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Filing: 1991-08-09
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Granted: 1994-06-07
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Expires: 2011-08-09
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Abstract

Abstract Transforms such as the DCT are useful for image compression. One close relative of the DCT is preferred for its arithmetic simplicity. A method and apparatus is described whereby the image compression is done with no multiplications while still compatible with a JPEG (Joint Photographic Experts Group) Transform. Other enhancements are made to improve image quality.

Inventors

  • 👤 Stephen M. Blonstein
  • 👤 James D. Allen
  • 👤 Martin P. Boliek

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 15:40
CPC Classifications
H; H04; H04N; H04N11/00; H04N11/04; H04N11/042; H04N11/044; G; G06; G06F; G06F17/00; G06F17/10; G06F17/14; G06F17/147; G06F7/00; G06F7/76; G06F7/78; G11; G11C; G11C19/00; G11C8/00; G11C8/12; H04N19/00; H04N19/10; H04N19/102; H04N19/124; H04N19/126; H04N19/60

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 93 words
An image compressor comprising horizontal transform means for receiving input pixels having a certain bit width and for horizontally transforming said input pixels using only a first adder array, transposition memory means for rotating the horizontally transformed pixels to vertical, vertical transform means for receiving the vertical pixels and for vertically transforming the vertical pixels using only a second adder array, and a single multiplier for receiving the transformed vertical pixels and for performing a single multiplication function on said transformed vertical pixels to provide compressed pixel data representative of said input pixels.
Claim 2
Dependent Claim 93 words
An image compressor comprising horizontal transform means for receiving input pixels having a certain bit width and for horizontally transforming said input pixels using only a first adder array, transposition memory means for rotating the horizontally transformed pixels to vertical, vertical transform means for receiving the vertical pixels and for vertically transforming the vertical pixels using only a second adder array, and a single multiplier for receiving the transformed vertical pixels and for performing a single multiplication function on said transformed vertical pixels to provide compressed pixel data representative of said input pixels.
Claim 3
Dependent Claim 92 words
An image compression system comprising means for receiving input image pixel data representative of an image, Generalized Chen transform (GCT) means for compressing said image data, said GCT means including a GCT adder for horizontally transforming said image data using only adders, transportion memory means for rotating the horizontally transformed pixels to vertical, said GCT adder including means for vertically transforming the vertical pixels using only said adders, and a single multiplier for performing a multiplication function on said transformed vertical pixels to provide compressed pixel data representative of said input pixels.
Claim 4
Dependent Claim 92 words
An image compression system comprising means for receiving input image pixel data representative of an image, Generalized Chen transform (GCT) means for compressing said image data, said GCT means including a GCT adder for horizontally transforming said image data using only adders, transportion memory means for rotating the horizontally transformed pixels to vertical, said GCT adder including means for vertically transforming the vertical pixels using only said adders, and a single multiplier for performing a multiplication function on said transformed vertical pixels to provide compressed pixel data representative of said input pixels.
Claim 5
Dependent Claim 48 words
An image compression system as in claim 2 wherein said GCT adder includes a first GCT adder network stage for transforming the first half of said horizontal and vertical transformations and a second GCT adder network stage for transforming the second half of said horizontal and vertical transformations.
Claim 6
Dependent Claim 16 words
An image compression system as in claim 3 wherein said single multiplier include zigzag order means.
Claim 7
Dependent Claim 15 words
An image compression system as in claim 3 wherein said single multiplier include rounder means.
Claim 8
Dependent Claim 16 words
An image compression system as in claim 4 wherein said single multiplier includes a multiplier table.
Claim 9
Dependent Claim 104 words
An image compressor comprising transform means for receiving input pixels having a certain bit width and for horizontally or vertically transforming said input pixels using only a first adder array, transposition memory means for rotating the horizontally or vertically transformed pixels to vertical or horizontal, said transform means for receiving the vertical or horizontal pixels and means for vertically or horizontally transforming the vertical or horizontal pixels using only said first adder array, and a single multiplier means for receiving the transformed pixels and for performing a single multiplication function on said transformed pixels to provide compressed pixel data representative of said input pixels.
Claim 10
Dependent Claim 104 words
An image compressor comprising transform means for receiving input pixels having a certain bit width and for horizontally or vertically transforming said input pixels using only a first adder array, transposition memory means for rotating the horizontally or vertically transformed pixels to vertical or horizontal, said transform means for receiving the vertical or horizontal pixels and means for vertically or horizontally transforming the vertical or horizontal pixels using only said first adder array, and a single multiplier means for receiving the transformed pixels and for performing a single multiplication function on said transformed pixels to provide compressed pixel data representative of said input pixels.

References Cited (Backward Citations)

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EP0412252A2 Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-06-06 1997-12-06 1998-06-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-06-06 2001-12-06 2002-06-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-06-06 2005-12-06 2006-06-07 $7700.00 Window Closed / Lapsed

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