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US5317428A Expired / Lapsed US ⏱️ 0.0 years remaining

Image encoding method and apparatus providing variable length bit stream signals

Assignee: Canon Inc
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Filing: 1992-11-25
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Granted: 1994-05-31
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Expires: 2012-11-25
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Abstract

Abstract There is provided an image encoding method in a facsimile apparatus or an image filing apparatus as an image communication apparatus. In this method, a color image signal which is expressed by a plurality of color component signals to be encoded is input, the input color image signal is converted into a bit stream signal, and the bit stream signal is encoded by the prediction encoding. A parameter for the prediction encoding is changed in accordance with the color image signal to be encoded. The encoding operation is executed adaptively to the color image signal to be encoded. By bit stream converting the binary color signal, the efficient encoding using the color correlation can be executed and an increase in data amount is prevented. By encoding the bit stream signal by using a dynamic arithmetic code, a binary color image can be efficiently encoded.

Inventors

  • 👤 Hidefumi Osawa
  • 👤 Yasuhiko Yasuda
  • 👤 Shigeo Kato

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 21:46
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/64; H04N1/642; G; G06; G06T; G06T9/00; G06T9/004; H04N1/41; H04N1/411; H04N1/413; H04N1/417; H04N1/648

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 107 words
An image encoding method comprising the steps of: for each pixel, inputting a plurality of color component signals representing one of N colors and the plurality of color component signals together representing a color of the pixel; for each pixel, sequentially converting the color component signals into a bit stream signal, the bit stream signal having a length dependent on the color of the pixel and comprising bits of logic "0" and/or logic "1", wherein a number of bits of logic "0" in the bit stream signal is different for each of the N colors; and sequentially encoding the bit stream signals using a binary encoding method.
Claim 2
Dependent Claim 107 words
An image encoding method comprising the steps of: for each pixel, inputting a plurality of color component signals representing one of N colors and the plurality of color component signals together representing a color of the pixel; for each pixel, sequentially converting the color component signals into a bit stream signal, the bit stream signal having a length dependent on the color of the pixel and comprising bits of logic "0" and/or logic "1", wherein a number of bits of logic "0" in the bit stream signal is different for each of the N colors; and sequentially encoding the bit stream signals using a binary encoding method.
Claim 3
Dependent Claim 20 words
A method according to claim 1, wherein in said encoding step, the bit stream signals are encoded by prediction encoding.
Claim 4
Dependent Claim 30 words
A method according to claim 2, wherein in said encoding step, a parameter for the prediction encoding is changed in accordance with the color represented by the color component signals.
Claim 5
Dependent Claim 22 words
A method according to claim 1, wherein in said encoding step, an adaptive encoding operation is executed for the bit stream signals.
Claim 6
Dependent Claim 20 words
A method according to claim 1, wherein the N colors are white, black, red, green, blue, cyan, magenta and yellow.
Claim 7
Dependent Claim 28 words
A method according to claim 1, wherein a number of consecutive bits of logic "0" in the bit stream signals are different for each of the N colors.
Claim 8
Dependent Claim 113 words
An image encoding apparatus comprising: inputting means for inputting, for each pixel, a plurality of color component signals representing one of N colors, and the plurality of color component signals together representing a color of the pixel; converting means for sequentially converting, for each pixel, the color component signals into a bit stream signal, the bit stream signal having a length dependent on the color of the pixel and comprising bits of logic "0" and/or logic "1", wherein a number of bits of logic "0" in the bit stream signal is different for each of the N colors; and encoding means for sequentially encoding the bit stream signals using a binary encoding method.
Claim 9
Dependent Claim 113 words
An image encoding apparatus comprising: inputting means for inputting, for each pixel, a plurality of color component signals representing one of N colors, and the plurality of color component signals together representing a color of the pixel; converting means for sequentially converting, for each pixel, the color component signals into a bit stream signal, the bit stream signal having a length dependent on the color of the pixel and comprising bits of logic "0" and/or logic "1", wherein a number of bits of logic "0" in the bit stream signal is different for each of the N colors; and encoding means for sequentially encoding the bit stream signals using a binary encoding method.
Claim 10
Dependent Claim 18 words
An apparatus according to claim 7, wherein said encoding means encodes the bit stream signals by prediction encoding.
Claim 11
Dependent Claim 30 words
An apparatus according to claim 8, wherein said encoding means encodes the bit stream signals in accordance with a parameter associated with the color represented by the color component signals.
Claim 12
Dependent Claim 20 words
An apparatus according to claim 7, wherein the N colors are white, black, red, green, blue, cyan, magenta and yellow.
Claim 13
Dependent Claim 28 words
An apparatus according to claim 7, wherein a number of consecutive bits of logic "0" in the bit stream signals are different for each of the N colors.

References Cited (Backward Citations)

US4344086A Cited
US4580162A Cited
GB2154826A Cited
US4905297A Cited
EP0284281A2 Cited
US4939583A Cited
US4847677A Cited
US4982282A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-05-30 1997-11-29 1998-05-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-05-30 2001-11-29 2002-05-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-05-30 2005-11-29 2006-05-31 $7700.00 Window Closed / Lapsed

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