Method for producing an electronic image from a photographic element

• US 5,609,978 A
• Filed: 06/06/1995
• Issued: 03/11/1997
• Est. Priority Date: 06/06/1995
• Status: Expired due to Term

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Sutton, James E., Smith, Teresa A., Simon, Richard A., Rivera, Jose E., Giorgianni, Edward J., Mittelstaedt, Brian E.
• Primary Examiner(s): Huff, Mark F.
• Application Number:
  US08/466,862
• Time in Patent Office: 644 Days
• Field of Search: 358/531, 358/527, 358/505, 358/506, 358/515, 358/518, 430/502, 430/503, 430/505, 430/506, 430/507, 430/508, 430/509, 430/510, 430/30
• US Class Current: 430/30
• CPC Class Codes: G03C 7/3041 Materials with specific sensitometric characteristics, e.g. gamma, density
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence

Abstract

A photographic element, is disclosed which includes a support and at least three silver halide emulsion layers, that records exposure information. The exposure information is recorded in three image-recording units and wherein the spectral sensitivities of said image-recording units are chosen such that the average color error, ΔE*_ab, is less than or equal to 3.1. ΔE*_ab is computed for a specified set of test colors of known spectral reflectance, and the light source is specified as D₆₅. ΔE*_ab is the average CIE 1976 (L*a*b*) ΔE*_ab between the CIE 1976 (L*a*b*)-space coordinates of said test colors and the CIE 1976 (L*a*b*)-space coordinates corresponding to transformed exposure signals. The transformed exposure signals are formed by applying an exposure-space matrix to the exposure signals derived from the photographic element to transform the derived exposure signals to exposure signals corresponding to the color-matching functions of the CCIR Recommendation 709 primary set. The exposure-space matrix is derived so as to minimize ##EQU1## and noise-gain factor, Ψ, defined as the sum of the square roots of the sum of the squares of each row of the elements in the exposure space matrix is less than or equal to 6.5.

Claims

1. A method of producing an electronic image comprising:

a) providing a photographic element that records exposure information, comprised of a support and three image-recording units coated upon said support, each image recording unit containing at least one silver halide emulsion layer, wherein said exposure information is recorded in the three image recording units and wherein the spectral sensitivities of said image recording units are chosen such that the average color error, Δ

E*_ab, is less than or equal to 3.1, wherein said Δ

E*_ab is computed for a specified set of 190 test colors of known spectral reflectance at 10 nm increments, and the light source is specified as D₆₅, and wherein said Δ

E*_ab is the average CIE 1976 (L*a*b*) Δ

E *_ab between the CIE 1976 (L*a*b*)-space coordinates of said test colors and the CIE 1976 (L*a*b*)-space coordinates corresponding to transformed exposure signals, wherein said transformed exposure signals are formed by applying an exposure-space matrix to the exposure signals derived from said photographic element to transform said derived exposure signals to exposure signals corresponding to the color-matching functions of the CCIR Recommendation 709 primary set, and wherein said exposure-space matrix is derived so as to minimize ##EQU22## and noise-gain factor, Ψ

, defined as the sum of the square roots of the sum of the squares of each row of the elements in the exposure space matrix is less than or equal to 6.5;

b) photographically processing said photographic element to produce image-bearing density records;

c) scanning said image-bearing density records on a pixel-wise basis with an opto-electronic scanner to produce image-bearing electronic signals;

d) digitizing said image-bearing electronic signals; and

e) producing the electronic image from said electronic image-bearing signals.

2. A method of producing the electronic image according to claim 1 further including compensating for optical crosstalk between image-bearing electronic signals.

3. A method of producing the electronic image according to claim 1 further including compensating for chemical crosstalk between image-beating electronic signals.

4. A method of producing the electronic image according to claim 1 further including converting density-dependent signals into corresponding exposure-dependent signals.

5. A method of producing the electronic image according to claim 1 further converting image-bearing electronic signals into a second set of image-bearing signals corresponding to an image recorded by a second image capture device of different imaging capabilities, specifically, said image capture device having different spectral sensitivities.

6. A method of producing the electronic image according to claim 1 further expressing the image-bearing signals in terms of any CIE color space description.

7. A method of producing the electronic image according to claim 1 further compensating for differences between scanning devices.

8. A method of producing the electronic image according to claim 1 further including compressing the image-bearing electronic signals prior to storage.

9. A method of producing an electronic image comprising:

a) providing a photographic element that records exposure information, comprised of a support and three image-recording units coated upon said support, each image recording unit containing at least one silver halide emulsion layer, wherein said exposure information is recorded in the three image recording units and wherein the spectral sensitivities of said image recording units are chosen such that the average color error, Δ

E*_ab, is less than or equal to 3.1, wherein said Δ

E*_ab is computed for a specified set of 190 test colors of known spectral reflectance at 10 nm increments, and the light source is specified as D₆₅, and wherein said Δ

E*_ab is the average CIE 1976 (L*a*b*) Δ

E *_ab between the CIE 1976 (L*a*b*)-space coordinates of said test colors and the CIE 1976 (L*a*b*)-space coordinates corresponding to transformed exposure signals, wherein said transformed exposure signals are formed by applying an exposure-space matrix to the exposure signals derived from said photographic element to transform said derived exposure signals to exposure signals corresponding to the color-matching functions of the CCIR Recommendation 709 primary set, and wherein said exposure-space matrix is derived so as to minimize ##EQU23## and noise-gain factor, Ψ

, defined as the sum of the square roots of the sum of the squares of each row of the elements in the exposure space matrix is less than or equal to 6.5;

b) photographically processing said photographic element to produce image-bearing density records;

c) scanning said image-bearing photographic element on a pixel-wise basis with an opto-electronic scanner to produce image-bearing electronic signals;

d) digitizing said image-bearing electronic signals;

e) converting said image-bearing electronic signals into density-representative electronic signals using a 1-dimensional look-up table;

f) subjecting said density-representative electronic signals to a matrix operation of at least three rows and three columns to produce a second set of density-representative electronic signals;

g) converting said second set of density-representative electronic signals into exposure-representative signals using three 1-dimensional look-up tables; and

h) converting said exposure-representative electronic signals into a second set of exposure-representative signals using a matrix operation of at least 3 rows and 3 columns.

10. A method of producing the electronic image according to claim 9 further including the following steps:

i) converting said exposure-representative electronic signals into a second set of exposure-representative electronic signals corresponding to image signals captured by an exposure recording device having spectral sensitivities corresponding to color matching functions for the intended output device by means of a matrix operation of at least 3 rows and 3 columns;

ii) converting said second set of exposure-representative signals into a set of output image-representative signals using three 1-dimensional look-up tables; and

iii) subjecting said output image representative signals to a matrix operation of at least 3 rows and 3 columns to produce a second set of output image representative signals.

11. A method of producing an electronic image comprising:

a) providing a photographic element that records exposure information, comprised of a support and three image recording units coated upon said support, each image recording unit containing at least one silver halide emulsion layer, wherein said exposure information is recorded in the three image recording units and wherein the spectral sensitivities of said image recording units are chosen such that the average color error, Δ

E*_ab, is less than or equal to 3.1, wherein said Δ

E*_ab is computed for a specified set of 190 test colors of known spectral reflectance at 10 nm increments, and the light source is specified as D₆₅, and wherein said Δ

E*_ab is the average CIE 1976 (L*a*b*) Δ

E*_ab between the CIE 1976 (L*a*b*)-space coordinates of said test colors and the CIE 1976 (L*a*b*)-space coordinates corresponding to transformed exposure signals, wherein said transformed exposure signals to formed by applying an exposure-space matrix to the exposure signals derived from said photographic element to transform said derived exposure signals to exposure signals corresponding to the color-matching functions of the CCIR Recommendation 709 primary set, and wherein said exposure-space matrix is derived so as to minimize ##EQU24## and noise-gain factor, Ψ

, defined as the sum of the square roots of the sum of the squares of each row of the elements in the exposure space matrix is less than or equal to 6.5;

b) photographically processing said photographic element to produce image-bearing density records;

c) scanning said image-bearing photographic element on a pixel-wise basis with an opto-electronic scanner to produce image-bearing electronic signals;

d) digitizing said image-bearing electronic signals;

e) converting said image-bearing electronic signals into a set of exposure-representative electronic signals using a 3-dimensional look-up table.

12. A method of producing the electronic image according to claim 11 further including the following steps:

i) converting said exposure-representative electronic signals into a second set of exposure-representative electronic signals corresponding to image signals captured by an exposure recording device having spectral sensitivities corresponding to color matching functions for the intended output device by means of a matrix operation of at least 3 rows and 3 columns;

ii) converting said second set of exposure-representative signals into a set of output image-representative signals using three 1-dimensional look-up tables; and

iii) subjecting said output image representative signals to a matrix operation of at least 3 rows and 3 columns to produce a second set of output image representative signals.

13. A method of producing an electronic image comprising:

a) providing a photographic element that records exposure information, comprised of a support and three image-recording units coated upon said support, each image recording unit containing at least one silver halide emulsion layer, wherein said exposure information is recorded in the three image recording units used in combination with a means of optical filtration external to said photographic element, wherein the spectral sensitivities of said image recording units are chosen such that the average color error, Δ

E*_ab, is less than or equal to 3.1, wherein said Δ

E*_ab is computed for a specified set of 190 test colors of known spectral reflectance at 10 nm increments, and the light source is specified as D₆₅, and wherein said Δ

E*_ab is the average CIE 1976 (L*a*b*) Δ

E*_ab between the CIE 1976 (L*a*b*)-space coordinates of said test colors and the CIE 1976 (L*a*b*)-space coordinates corresponding to transformed exposure signals, wherein said transformed exposure signals are formed by applying an exposure-space matrix to the exposure signals derived from said photographic element to transform said derived exposure signals to exposure signals corresponding to the color-matching functions of the CCIR Recommendation 709 primary set, and wherein said exposure-space matrix is derived so as to minimize ##EQU25## and noise-gain factor, Ψ

, defined as the sum of the square roots of the sum of the squares of each row of the elements in the exposure space matrix is less than or equal to 6.5;

b) recording an image of an object illuminated by scene illumination and optical filtration in the photographic element;

c) photographically processing said photographic element to produce image-bearing density records;

d) scanning said image-bearing density records on a pixel-wise basis with an opto-electronic scanner to produce image-bearing electronic signals;

e) digitizing said image-bearing electronic signals; and

f) producing the electronic image from said electronic image-bearing signals.

14. A method of producing the electronic image according to claim 13 wherein said means of optical filtration is located between the recorded object and the photographic element.

15. A method of producing the electronic image according to claim 14 wherein said means of optical filtration is a transparent sheet having spectrally selective transmission.

16. A method of producing the electronic image according to claim 14 wherein said means of optical filtration is a solution having spectrally selective absorption contained in a transparent cell.

17. A method of producing the electronic image according to claim 14 wherein said means of optical filtration is a solution having spectrally selective absorption contained in a transparent filter cell in combination with a transparent sheet having spectrally selective transmission.

18. A method of producing the electronic image according to claim 13 wherein said means of optical filtration is located between the source of scene illumination and the recorded object.

19. A method of producing the electronic image according to claim 18 wherein said means of optical filtration is a transparent sheet having spectrally selective transmission.