Patent US5562604A successfully refreshed from Google Patents.
Patent EP0265827A2 successfully refreshed from Google Patents.
Patent US6724941B1 successfully refreshed from Google Patents.
← Back to Patent Explorer
US6724941B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Image processing method, image processing device, and recording medium

Assignee: Fujifilm Corp
•
Filing: 1999-09-30
•
Granted: 2004-04-20
•
Expires: 2019-09-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An image processing method includes a step for inputting the type of digital camera used for obtaining an original image signal to be processed, a step for preparing a non-sharp mask signal of the original image signal, a step for reading a contrast table and a density dependent table corresponding to the type of digital camera from a hard disk device, a step for carrying out sharpness enhancement processing based on the contrast table, the density dependent table, the non-sharp mask signal and the original image signal so that the maximum value of responses of the spatial frequency characteristics of an image signal on which the sharpness enhancement processing has been effected is a value in the region of 1.5 to 3.0 times the spatial frequency characteristics of the original image signal. Accordingly, spatial frequency enhancement processing can be carried out under preferred processing conditions on the original image signal obtained by the digital still camera.

Inventors

  • 👤 Tatsuya Aoyama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:04
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/73; G06T5/75

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 199 words
An image processing method, wherein a spatial frequency enhancement processing is carried out on an original image signal obtained by photography using a digital still camera in such a manner that a maximum value of responses of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is a value substantially in the range of 1.5 to 3.0 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet, and wherein the spatial frequency enhancement processing is carried out based on the following expression: S proc =S org +G ( S org )× F ( S org −S us ) in which S org expresses the original image signal, S us expresses a non-sharp mask signal, G (S org ) expresses a function dependent on the original image signal S org , and F (S org −S us ) expresses a function dependent on a contrast value of the original image signal, wherein the contrast value is obtained by subtracting the non-sharp mask signal S us from the original image signal S org .
Claim 2
Dependent Claim 199 words
An image processing method, wherein a spatial frequency enhancement processing is carried out on an original image signal obtained by photography using a digital still camera in such a manner that a maximum value of responses of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is a value substantially in the range of 1.5 to 3.0 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet, and wherein the spatial frequency enhancement processing is carried out based on the following expression: S proc =S org +G ( S org )× F ( S org −S us ) in which S org expresses the original image signal, S us expresses a non-sharp mask signal, G (S org ) expresses a function dependent on the original image signal S org , and F (S org −S us ) expresses a function dependent on a contrast value of the original image signal, wherein the contrast value is obtained by subtracting the non-sharp mask signal S us from the original image signal S org .
Claim 3
Dependent Claim 88 words
The image processing method according to claim 1 , wherein the spatial frequency characteristics of the non-sharp mask signal S us is such that on an image outputted by using an image signal on which the spatial frequency enhancement processing has been effected utilizing the non-sharp mask signal S us , a response of the spatial frequency of 0 to 0.5 cycle/mm is equal to or less than 1.2 times the response of the image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 4
Dependent Claim 43 words
The image processing method according to claim 1 , wherein a magnitude of the function F (S org −S us ) is smaller than a magnitude of the contrast value if the magnitude of the contrast value is below a predetermined contrast threshold.
Claim 5
Dependent Claim 43 words
The image processing method according to claim 2 , wherein a magnitude of the function F (S org −S us ) is smaller than a magnitude of the contrast value if the magnitude of the contrast value is below a predetermined contrast threshold.
Claim 6
Dependent Claim 34 words
The image processing method according to claim 3 , wherein the function F (S org −S us ) is 0 when the magnitude of the contrast value is smaller than the predetermined contrast threshold.
Claim 7
Dependent Claim 34 words
The image processing method according to claim 4 , wherein the function F (S org −S us ) is 0 when the magnitude of the contrast value is smaller than a predetermined contrast threshold.
Claim 8
Dependent Claim 39 words
The image processing method according to claim 1 , wherein a value of the function G (S org ) decreases as a density of the image on which the spatial frequency enhancement processing has not been effected yet increases.
Claim 9
Dependent Claim 39 words
The image processing method according to claim 2 , wherein a value of the function G (S org ) decreases as a density of the image on which the spatial frequency enhancement processing has not been effected yet increases.
Claim 10
Dependent Claim 40 words
An The image processing method according to claim 3 , wherein a value of the function G (S org ) decreases as a density of the image on which the spatial frequency enhancement processing has not been effected yet increases.
Claim 11
Dependent Claim 39 words
The image processing method according to claim 5 , wherein a value of the function G (S org ) decreases as a density of the image on which the spatial frequency enhancement processing has not been effected yet increases.
Claim 12
Dependent Claim 163 words
An image processing method, wherein an enlargement processing or reduction processing is carried out on an original image signal obtained by photography using a digital still camera, and, in carrying out a spatial frequency enhancement processing, a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is adjusted according to the spatial frequency characteristics of the enlargement processing or the reduction processing, and wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 13
Dependent Claim 163 words
An image processing method, wherein an enlargement processing or reduction processing is carried out on an original image signal obtained by photography using a digital still camera, and, in carrying out a spatial frequency enhancement processing, a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is adjusted according to the spatial frequency characteristics of the enlargement processing or the reduction processing, and wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 14
Dependent Claim 43 words
An The image processing method according to claim 11 , wherein the adjustment is an adjustment in accordance with a scale of enlargement when the enlargement processing is carried out, or with a scale of reduction when the reduction processing is carried out.
Claim 15
Dependent Claim 157 words
An image processing device, comprising: enlargement/reduction means for carrying out enlargement processing or reduction processing on an original image signal obtained by photography using a digital still camera; and adjusting means for adjusting a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected, according to the spatial frequency characteristics of the enlargement processing or the reduction processing, wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 16
Dependent Claim 157 words
An image processing device, comprising: enlargement/reduction means for carrying out enlargement processing or reduction processing on an original image signal obtained by photography using a digital still camera; and adjusting means for adjusting a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected, according to the spatial frequency characteristics of the enlargement processing or the reduction processing, wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 17
Dependent Claim 173 words
A recording medium having a program recorded thereon for allowing a computer to execute processing that includes: a step in which enlargement processing or reduction processing is carried out on an original image signal obtained by photography using a digital still camera; and a step in which a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is adjusted according to the spatial frequency characteristics of the enlargement processing or the reduction processing, wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 18
Dependent Claim 173 words
A recording medium having a program recorded thereon for allowing a computer to execute processing that includes: a step in which enlargement processing or reduction processing is carried out on an original image signal obtained by photography using a digital still camera; and a step in which a response of the spatial frequency characteristics of an image signal on which the spatial frequency enhancement processing has been effected is adjusted according to the spatial frequency characteristics of the enlargement processing or the reduction processing, wherein the adjustment is such that a maximum value of responses of the spatial frequency characteristics, in which the spatial frequency characteristics of the enlargement processing or the reduction processing and the spatial frequency characteristics of the image signal on which the spatial frequency enhancement processing has been effected are combined, is a value in the range of 1.0 to 2.5 times a maximum value of responses of the spatial frequency characteristics of the original image signal on which the spatial frequency enhancement processing has not been effected yet.
Claim 19
Dependent Claim 26 words
The image processing method according to claim 1 , wherein an enhancement is suppressed for image portions whose frequency bands are below a predetermined frequency threshold.
Claim 20
Dependent Claim 25 words
The image processing method according to claim 1 , wherein an enhancement is suppressed for image portions whose contrasts are below a predetermined contrast threshold.
Claim 21
Dependent Claim 84 words
The image processing method according to claim 1 , wherein the spatial frequency enhancement processing is carried out based on the following expression: S proc (ω 1 ,ω 2 )= S org (ω 1 ,ω 2 )× H (ω 1 ,ω 2 ) in which S org (ω 1 , ω 2 ) represents an original signal S org (x, y) is converted into a signal on a frequency axis and H (ω 1 , ω 2 ) is a high frequency enhancement filter.
Claim 22
Dependent Claim 34 words
The image processing method according to claim 17 , wherein H (ω 1 , ω 2 )=1+c {sin 2 (ω 1 /2)+sin 2 (ω 2 /2)} and c is a constant value above 0.

References Cited (Backward Citations)

JPS61109550A Cited
US6075902A Cited
US5978522A Cited
US5696850A Cited
US6055340A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2007-04-20 2007-10-20 2008-04-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2011-04-20 2011-10-20 2012-04-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2015-04-20 2015-10-20 2016-04-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag