U.S. patent application number 11/507535 was filed with the patent office on 2007-01-18 for method of converting image signal, method of determining original color of color image, and apparatus for converting image signal.
This patent application is currently assigned to FUJI PHOTO FILM CO., LTD.. Invention is credited to Takahiro Okamoto.
Application Number | 20070013929 11/507535 |
Document ID | / |
Family ID | 17375828 |
Filed Date | 2007-01-18 |
United States Patent
Application |
20070013929 |
Kind Code |
A1 |
Okamoto; Takahiro |
January 18, 2007 |
Method of converting image signal, method of determining original
color of color image, and apparatus for converting image signal
Abstract
A new calibration scale is proposed for as a substitute for
density values of a densitometer or equivalent neutral densities. A
color reproduction range of a color reversal film is set on an xy
chromaticity diagram. On the xy chromaticity diagram, there are
established three straight lines passing through a chromaticity
point corresponding to a standard white illuminant and principal
wavelengths relative to primary colors R, G, B. Vertexes of a
triangle containing the color reproduction range are determined on
the three straight lines. Chromaticity values at the vertexes of
said triangle are determined as primary colors R, G, B. Block dye
density values c, m, y corresponding to the primary colors R, G, B
are determined according to the equations R=10.sup.-c, G=10.sup.-m,
B=10.sup.-y. The determined block dye density values c, m, y are
used as a new calibration scale. Since the block dye density values
have properties similar to conventional density values as compared
with colorimetric values, conventional image processing resources
can be utilized.
Inventors: |
Okamoto; Takahiro;
(Minamiashigara-shi, JP) |
Correspondence
Address: |
SUGHRUE, MION, ZINN, MACPEAK & SEAS, PLLC
2100 Pennsylvania Avenue, N.W.
Washington
DC
20037-3213
US
|
Assignee: |
FUJI PHOTO FILM CO., LTD.
|
Family ID: |
17375828 |
Appl. No.: |
11/507535 |
Filed: |
August 22, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09662900 |
Sep 15, 2000 |
|
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11507535 |
Aug 22, 2006 |
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Current U.S.
Class: |
358/1.9 ;
358/518 |
Current CPC
Class: |
H04N 1/6025 20130101;
H04N 1/6033 20130101 |
Class at
Publication: |
358/001.9 ;
358/518 |
International
Class: |
G03F 3/08 20060101
G03F003/08 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 16, 1999 |
JP |
11-262440 |
Claims
1. A method of converting device-dependent image signals into
device-independent image signals, comprising the step of:
converting device-dependent image signals into device-independent
image signals representing densities with block dyes.
2. A method of converting device-dependent image signals into
device-independent image signals, comprising the steps of:
converting device-dependent image signals supplied from an input
device which reads an image subject into device-independent image
signals representing densities with block dyes; and converting said
device-independent image signals into device-dependent image
signals for an output device.
3. A method according to claim 1, wherein said device-dependent
image signals comprise R, G, B signals or C, M, Y signals, and said
device-independent image signals comprise C, M, Y signals
representing densities with block dyes.
4. A method of determining primary colors of a color image,
comprising the steps of: setting a color reproduction range of the
color image on an xy chromaticity diagram; setting three straight
lines extending through a chromaticity point corresponding to a
standard white illuminant on said xy chromaticity diagram and
principal wavelengths relative to primary colors in said color
reproduction range; determining the vertexes of a triangle
containing said color reproduction range on said three straight
lines; and determining choromaticity values at the vertexes of said
triangle as primary colors.
5. A method according to claim 4, wherein said color image is
carried on a color reversal film or a reflective color print.
6. An apparatus for converting device-dependent image signals into
device-independent image signals, comprising: an input converter
for converting device-dependent image signals into
device-independent image signals representing densities with block
dyes.
7. An apparatus for converting device-dependent image signals into
device-independent image signals, comprising: an input converter
for converting device-dependent image signals supplied from an
input device which reads an image subject into device-independent
image signals representing densities with block dyes; and an output
converter for converting said device-independent image signals into
device-dependent image signals for an output device.
8. An apparatus according to claim 6, wherein said device-dependent
image signals comprise R, G, B signals or C, M, Y signals, and said
device-independent image signals comprise C, M, Y signals
representing densities with block dyes.
9.-11. (canceled)
12. The method of claim 1, wherein the converting comprises
converting each color of device-dependent image signals into color
signals of the device-independent image signals representing
densities with multiple colored block dyes.
13. The apparatus of claim 6, said input converter converting each
color of device-dependent image signals into color signals of the
device-independent image signals representing densities with
multiple colored block dyes.
14. The apparatus of claim 7, converting each color of
device-dependent image signals into color signals of the
device-independent image signals representing densities with
multiple colored block dyes.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method of converting a
device-dependent image signal produced by a color scanner
(hereinafter referred to as "scanner"), a digital camera, etc.,
into a device-independent image signal, a method of determining an
original color in a color reproduction range of a color image that
is recorded on a color reversal film, and an apparatus for
converting a device-dependent image signal into a
device-independent image signal.
[0003] 2. Description of the Related Art
[0004] For image processing, it has heretofore been customary to
covert a device-dependent image signal produced by a scanner, which
is an image input device, into a density value on a densitometer or
an equivalent neutral density as disclosed in Japanese laid-open
patent publication No. 6-237373 and Japanese laid-open patent
publication No. 6-261208, and process an image signal represented
by the density value or the equivalent neutral density, i.e., a
density-based image signal, for sharpness, set-up, or color
correction processing.
[0005] In recent years, there has been established a standard color
management technique for converting a device-dependent image signal
produced by a scanner, a digital camera, etc., which is an image
input device, into a device-independent image signal representing
colorimetric values X, Y, Z or L*, a*, b*, processing the
device-independent image signal, and then converting the processed
device-independent image signal into a device-dependent image
signal for use by a printing press, a printer, or a display
monitor.
[0006] However, the image processing process which processes the
device-independent image signal based on the colorimetric values
fails to utilize the image processing technique that uses
density-based image signals as conventional image processing
resources.
SUMMARY OF THE INVENTION
[0007] It is therefore an object of the present invention to
provide a method of converting a device-dependent image signal into
a novel device-independent image signal, which replaces density
values on a densitometer or equivalent neutral densities or
colorimetric values, a method of determining an original color of a
color image, and an apparatus for converting a device-dependent
image signal into a device-independent image signal.
[0008] According to an aspect the present invention, there is
provided a method of converting device-dependent image signals into
device-independent image signals, comprising the step of converting
device-dependent image signals into device-independent image
signals representing densities (density values or density scale)
with block dyes. Since the device-independent image signals
representing densities with block dyes have properties similar to
conventional density Values and equivalent neutral density values,
they can be handled with ease, e.g., they have excellent
organoleptic properties. The device-independent image signals can
highly accurately be converted into colorimetric values through
simple calculations.
[0009] According to another aspect of the present invention, there
is also provided a method of converting device-dependent image
signals into device-independent image signals, comprising the steps
of converting device-dependent image signals supplied from an input
device which reads an image subject into device-independent image
signals representing densities with block dyes, and converting the
device-independent image signals into device-dependent image
signals for an output device.
[0010] The device-dependent image signals may comprise R, G, B
signals or C, M, Y signals, and the device-independent image
signals may comprise C, M, Y signals representing densities with
block dyes. Therefore, R, G, B signals and C, M, Y signals
outputted from an image input device such as a digital camera, a
scanner, or the like may be handled as C, M, Y signals representing
densities with block dyes.
[0011] According to still another aspect of the present invention,
there is further provided a method of determining primary colors of
a color image, comprising the steps of setting a color reproduction
range of the color image on an xy chromaticity diagram, setting
three straight lines extending through a chromaticity point
corresponding to a standard white illuminant on the xy chromaticity
diagram and principal wavelengths relative to primary colors in the
color reproduction range, determining the vertexes of a triangle
containing the color reproduction range on the three straight
lines, and determining choromaticity values at the vertexes of the
triangle as primary colors. Density values of block dyes can be
calculated from the determined primary colors.
[0012] The color image may be carried on a color reversal film or a
reflective color print.
[0013] According to yet another aspect of the present invention,
there is further provided an apparatus for converting
device-dependent image signals into device-independent image
signals, comprising an input converter for converting
device-dependent image signals into device-independent image
signals representing densities with block dyes.
[0014] With the above apparatus, because the device-independent
image signals representing densities with block dyes have
properties similar to conventional density values and equivalent
neutral density values, they can be handled with ease, e.g., they
have excellent organoleptic properties. The device-independent
image signals can highly accurately be converted into colorimetric
values through simple calculations.
[0015] According to yet still another aspect of the present
invention, there is provided an apparatus for converting
device-dependent image signals into device-independent image
signals, comprising an input converter for converting
device-dependent image signals supplied from an input device which
reads an image subject into device-independent image signals
representing densities with block dyes, and an output converter for
converting the device-independent image signals into
device-dependent image signals for an output device.
[0016] In the above apparatus, the device-dependent image signals
may comprise R, G, B signals or C, M, Y signals, and the
device-independent image signals may comprise C, M, Y signals
representing densities with block dyes. Therefore, R, G, B signals
and C, M, Y signals outputted from an image input device such as a
digital camera, a scanner, or the like may be handled as C, M, Y
signals representing densities with block dyes.
[0017] According to a further aspect of the present invention,
there is provided an apparatus for converting device-dependent
image signals into device-independent image signals, comprising a
plurality of one-dimensional conversion tables for processing
device-dependent image signals supplied from an input device which
reads an image subject, with respective predetermined functions, a
table selector for selecting one of the one-dimensional conversion
tables which is optimum for the input device, and an input
converter for converting the device-dependent image signals
processed by the one-dimensional conversion table which is selected
by the table selector, into device-independent image signals
representing densities with block dyes. One of the one-dimensional
conversion tables can be selected depending on the input device,
which may comprise a digital camera, a scanner, or the like. Thus,
the obtained device-independent image signals representing
densities with block dyes well match the device-dependent image
signals supplied from the input device.
[0018] The table selector may comprise means for using block dye
densities determined from a reference color chart as target values,
means for processing, as input values, image signals which are
produced by reading the reference color chart with the input device
and processed by the one-dimensional conversion tables, according
to a predetermined polynomial, thereby to produce calculated
values, and means for selecting one of the one-dimensional
conversion tables which outputs the input values corresponding to
those of the calculated values which are closest to the target
values, as the one-dimensional conversion table which is optimum
for the input device.
[0019] The predetermined polynomial may comprise a polynomial based
on a regression analysis.
[0020] The above and other objects, features, and advantages of the
present invention will become more apparent from the following
description when taken in conjunction with the accompanying
drawings in which preferred embodiments of the present invention
are shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a diagram illustrative of block dyes;
[0022] FIG. 2 is a block diagram of an image processing system
according to the present invention;
[0023] FIG. 3 is a detailed block diagram of a color processor in
the image processing system shown in FIG. 2;
[0024] FIG. 4 is a flowchart of an operation sequence of the image
processing system shown in FIG. 2;
[0025] FIG. 5 is a diagram illustrative of details of an IT8
chart;
[0026] FIG. 6 is a flowchart of an operation sequence of a process
of determining a block dye density;
[0027] FIG. 7 is a chromaticity diagram illustrative of a color
reproduction range of a color reversal film;
[0028] FIG. 8 is a chromaticity diagram illustrative of a process
of three straight lines;
[0029] FIG. 9 is a chromaticity diagram illustrative of a process
of determining the vertexes of a triangle;
[0030] FIG. 10 is a block diagram of an apparatus for converting an
image signal;
[0031] FIG. 11 is a block diagram of another apparatus for
converting an image signal; and
[0032] FIG. 12 is a block diagram of still another apparatus for
converting an image signal.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Prior to describing embodiments of the present invention,
block dyes and the relationship of conversion between the block
dyes and colorimetric values will be described below for an easier
understanding of the embodiments of the present invention.
[0034] Block dyes are described in "Fundamentals of color
reproduction engineering", written by Noboru Ohta, published by
Corona Co., Ltd., Sep. 10, 1997, 1st edition, 1st printing, pages
105-107 (hereinafter referred to as "literature 1").
[0035] Block dyes are dyes whose spectral absorption curves are of
block shape. As shown in FIG. 1, a block dye Y (yellow) has a
density (also referred to as "density value" or "density scale") D
having a uniform density value y (D=y) between wavelengths .lamda.1
and .lamda.2. A block dye M (magenta) has a density D having a
uniform density value m (D=m) between wavelengths .lamda.2 and
.lamda.3. A block dye C (cyan) has a density D having a uniform
density value c (D=c) between wavelengths .lamda.3 and .lamda.4. As
well known in the art, the density D can be expressed by the
following equation (1): D=-log.sub.10 T.rarw..fwdarw.T=10.sup.-D
(1) where T (.lamda.) represents spectral transmittance.
[0036] According to the present invention, the density values c, m,
y of the block dyes C, M, Y which express the colors of a color
image (subject) recorded on a color reversal film, a reflective
color print, etc. are density values converted (calibrated) into a
novel device-dependent image signal which replaces density values
on a densitometer or equivalent neutral densities or colorimetric
values.
[0037] The wavelength ranges of the block dyes C, M, Y do not need
to share a wavelength between the block dyes Y, M or between the
block dyes M, C, as shown in FIG. 1. Rather, the wavelength ranges
of the block dyes Y, M or the block dyes M, C may overlap each
other, or may be spaced from each other by a wavelength gap
therebetween.
[0038] A colorimetric value X is expressed by the equation (2), and
can be developed according to the equations (3), (4) in view of the
above properties of the block dyes C, M, Y. X = .times. .intg. T
.function. ( .lamda. ) P .function. ( .lamda. ) x .function. (
.lamda. ) .times. d .lamda. = .times. 10 - c .times. .intg. P
.function. ( .lamda. ) x .function. ( .lamda. ) .times. d .lamda. +
10 - m .times. .intg. P .function. ( .lamda. ) x .function. (
.lamda. ) .times. d .lamda. + 10 - Y .times. .intg. P .function. (
.lamda. ) x .function. ( .lamda. ) .times. d .lamda. = .times. 10 -
c Xr + 10 - m Xg + 10 - y Xb ( 2 ) ( 3 ) ( 4 ) ##EQU1##
[0039] In the equation (2), the range of the integral .intg.
represents the visible wavelength range. In the equation (3), the
range of the integral .intg. of the first term on the right side
represents the range between .lamda.3 and .lamda.4, the range of
the integral .intg. of the second term of the right side represents
the range between .lamda.2 and .lamda.3, and the range of the
integral .intg. of the third term of the right side represents the
range between .lamda.1 and .lamda.2.
[0040] In the equation (4), Xr, Xg, Xb represent
Xr=.intg.P(.lamda.)x(.lamda.)d.lamda. (the range of the integral
.intg. represents the range between .lamda.3 and .lamda.4),
Xg=.intg.P(.lamda.)x(.lamda.)d.lamda. (the range of the integral
.intg. represents the range between .lamda.2 and .lamda.3),
Xb=.intg.P(.lamda.)x(.lamda.)d.lamda. (the range of the integral
.intg. represents the range between .lamda.1 and .lamda.2),
respectively.
[0041] Therefore, the block dyes C, M, Y can easily be converted
into colorimetric values X, Y, Z by matrix and product sum
operations, rather than integral operations, according to the
following matrix equation (5): [ X Y Z ] = [ X r X g X b Y r Y g Y
b Z r Z g Z b ] .function. [ 10 - c 10 - m 10 - y ] ( 5 )
##EQU2##
[0042] Since the colorimetric values X, Y, Z and colorimetric
values L*, a*, b* can uniquely be converted between each other
according to colorimetric equations, the term "colorimetric values"
used herein represent either the X, Y, Z values or the L*, a*, b*
values.
[0043] The elements of the matrixes according to the equation (5)
can be determined irrespective of wavelengths, as described
below.
[0044] It is assumed that primary colors (which may actually
include imaginary primary colors that do not exit) R, G, B are
equal to the transmittances 10.sup.-c, 10.sup.-m, 10.sup.-y,
respectively, of the block dyes C, M, Y in the equation (5), as
indicated by the following equation (6): R=10.sup.-c, G=10.sup.-m,
B=10.sup.-y (6)
[0045] By substituting the equation (6) in the equation (5), the
following equation (7) is obtained: [ X Y Z ] = [ X r X g X b Y r Y
g Y b Z r Z g Z b ] .function. [ R G B ] ( 7 ) ##EQU3##
[0046] According to the equation (7), the subtractive mixture of
the block dyes C, M, Y can be replaced with the additive mixture,
and hence can be handled in the same manner as the additive
mixture.
[0047] Therefore, if imaginary primary color R, G, B values with
respect to a color image recorded on a color reversal film or the
like are initially determined, then density values c, m, y of
imaginary block dyes C, M, Y corresponding to the primary color R,
G, B values can be estimated, i.e., calculated, from the primary
color R, G, B according to the equation (6).
[0048] In the embodiments described below, imaginary primary color
R, G, B values are initially determined, and then density values c,
m, y of imaginary block dyes C, M, Y corresponding to the primary
color R, G, B values are determined. A process of determining the
elements Xr, Xg, Xb, Yr, Yg, Yb, Zr, Zg, Zb of the matrix according
to the equation (7) when the primary color R, G, B values are
initially determined is disclosed in "Fundamentals of calorimetric
engi-'neering", written by Gakuo Ikeda, published by Corona Co.,
Ltd., Oct. 15, 1989, 6th printing, pages 125-130 (hereinafter
referred to as "literature 2w).
[0049] The process of determining the elements Xr, Xg, Xb, Yr, Yg,
Yb, Zr, Zg, Zb will be described below.
[0050] A general formula for converting primary color R, G, B
values into calorimetric values X, Y, Z is given by the following
equation (8): [ R G B ] = [ R X R Y R Z G X G Y G Z B X B Y B Z ]
.function. [ X Y Z ] ( 8 ) ##EQU4##
[0051] In the equation (8), the values of the matrix elements Rx,
Ry, Rz, Gx, Gy, Gz, Bx, By, Bz, i.e., the coefficients of the
elements X, Y, Z of the right matrix on the right side, can be
determined by specifying x, Y chromaticity values of the primary
colors R, G, B on the left side and x, Y chromaticity values of a
standard illuminant (white) according to the CIE, as described in
the above pages of the literature 2.
[0052] The equation (8) can be modified into the following equation
(9): [ X Y Z ] = [ R X R Y R Z G X G Y G Z B X B Y B Z ] - 1
.function. [ R G B ] ( 9 ) ##EQU5##
[0053] If the left inverse matrix on the right side of the equation
(9) and the left matrix on the right side of the equation (7) are
made equal to each other as shown by the equation (10) below, then
the elements Xr, Xg, Xb, Yr, Yg, Yb, Zr, Zg, Zb of the matrixes
according to the equation (7) when the primary color R, G, B values
are initially determined can be determined. [ X r X g X b Y r Y g Y
b Z r Z g Z b ] = [ R X R Y R Z G X G Y G Z B X B Y B Z ] - 1 ( 10
) ##EQU6##
[0054] The block dyes and the relationship of conversion between
the block dyes and colorimetric values have been described
above.
[0055] Now, an image processing system 10 according to the present
invention will be described below.
[0056] FIG. 2 shows in block form the image processing system
10.
[0057] As shown in FIG. 2, the image processing system 10 basically
comprises a scanner 14 as an image input device (also referred to
as" image reading devices or "image input device"), and an image
processor 15 connected to the scanner 14.
[0058] The scanner 14 scans a color reversal film 12 as a subject
with an optical system, and outputs device-dependent image signals
(R, G, B) representing color-separated pixel signals to the image
processor 15.
[0059] The image processor 15 converts the device-dependent image
signals (R, G, B) from the scanner 14 into device-dependent image
signals (C, M, Y, K), for example, for printing.
[0060] The image processor 15 comprises a computer for carrying out
a series of calculations or a data processing sequence according to
a program. Specifically, the image processor 15 comprises a
computer unit having a CPU, a memory, etc., an input device
including a mouse, a keyboard, etc. connected to the computer unit,
and a display unit such as a CRT display or the like connected to
the computer unit.
[0061] The image processor 15 has a linear conversion table (also
referred to as "one-dimensional LUT") 16 as a one-dimensional LUT
(Look-Up Table) for converting the device-dependent image signals
(R, G, B) from the scanner 14 into image signals (C, M, Y)=(Ca, Ma,
Ya) as intermediate values, a logarithmic conversion table (also
referred to as "one-dimensional LUT") 18 as a one-dimensional LUT
for converting the device-dependent image signals (R, G, B) from
the scanner 14 into image signals (C, M, Y)=(Cb, Mb, Yb) as
intermediate values, and a luminance logarithmic conversion table
(also referred to as "one-dimensional LUT") 20 as a one-dimensional
LUT for converting the device-dependent image signals (R, G, B)
from the scanner 14 into image signals (C, M, Y)=(Cc, Mc, Yc) as
intermediate values.
[0062] These one-dimensional LUTs 16, 18, 20 are tables inserted
for either converting signals which cannot easily be approximated
by a polynomial, described later on, according to predetermined
functions thereby to increase the accuracy of approximation by the
polynomial, or reducing the number of terms of the polynomial if
the accuracy of approximation may remain unchanged.
[0063] The linear conversion table 16 has a function to linearly
convert the supplied image signals (R, G, B) according to
respective linear equations.
[0064] The logarithmic conversion table 18 has a function to
logarithmically convert the image signals obtained as luminance
signals into image signals as density signals.
[0065] The luminance logarithmic conversion table 20 has a function
to convert an L* value in the CIELAB color space into a luminance
and thereafter logarithmically convert the luminance.
[0066] The image signals (Ca, Ma, Ya), (Cb, Mb, Yb), (Cc, Mc, Yc)
as intermediate values outputted respectively from the
one-dimensional LUTs 16, 18, 20 are supplied to a table selecting
calculator 22 for selecting either one of the one-dimensional LUTs
16, 18, 20.
[0067] The table selecting calculator 22 performs given
calculations using block dye density values (C', M', Y') generated
by a target generator 24 as target values, selects one of the
one-dimensional LUTs 16, 18, 20 which outputs image signals closest
to the target values when'the table selecting calculator 22
calculates the polynomial using the image signals (Ca, Ma, Ya),
(Cb, Mb, Yb), (Cc, Mc, Yc) as intermediate values, switches a table
selector 28 which comprises a multiplexer, and holds coefficients
Bm of the determined polynomial in a coefficient holder 26 as a
memory.
[0068] The image processor 15 also has a DDC (Device-Dependent
Color)/DIC (Device-Independent Color) converter 30 as a polynomial
calculator for converting device-dependent image data into
device-independent image data. The DDC/DIC converter 30 converts
the device-dependent image signals from one of the one-dimensional
LUTs 16, 18, 20 which has been selected by the table selector 28,
into block dye density values (C, M, Y) as device-independent image
signals according to a given polynomial whose cofficients Bm are
supplied from the coefficient holder 26.
[0069] The block dye density values (C, M, Y) are then converted by
a color processor 32 into device-dependent-image signals (C, M, Y,
K) as halftone dot % (halftone dot area ratio) signals if the
output device (image output device) comprises a printing press, for
example.
[0070] In the image processor 15, as described above, the
device-dependent image signals (R, G, B) outputted from the scanner
14 via one of the one-dimensional LUTs 16, 18, 20 and the table
selector 28 to the DDC/DIC converter 30, and then converted into
device-dependent image signals (C, M, Y, K) for printing by the
DDC/DIC converter 30 and the color processor 32.
[0071] Actually, when the device-dependent image signals (R, G, B)
outputted from the scanner 14 or the like are supplied to the image
processor 15, the table selecting calculator 22 selects the signals
from one of the one-dimensional LUTs 16, 18, 20 which approximate
the block dye density values (C', M', Y') as target values most
accurately. Thereafter, a combined LUT generator 34 combines or
merges the selected one of the one-dimensional LUTs 16, 18, 20, the
DDC/DIC converter 30, and the color processor 32 into a combined
LUT, and stores the combined LUT into a combined LUT setting unit
36 as a memory. The device-dependent image signals (R, G, B)
outputted from the scanner 14 is converted into the
device-dependent image signals (R, G, B) for printing, by the
device-dependent image signals (R, G, B) stored in the combined LUT
setting unit 36, i.e., one LUT.
[0072] The coefficient holder 26 is required to comprise an
electrically erasable programmable ROM such as a flash memory or
the like. The combined LUT setting unit 36 may comprise a RAM such
as a volatile memory incorporated as a working memory in the
computer.
[0073] The components of the image processor 15 which range from
the one-dimensional LUTs 16, 18, 20 to the DDC/DIC converter 30
perform an input converting process, the color processor 32
performs an output converting process.
[0074] The color processor 32 which performs an output converting
process will be described as to its arrangement and operation in
detail below. The color processor 32 generates a density signal K
based on the setting of densities including highlights (HL) and
shadows (SD), the gradation conversion for each color, the
adjustment of the gray balance, color correction, and UCR (Under
Color Removal) according to image processing conditions that are
specified by the operator using input device including a mouse, a
keyboard, etc. The color processor 32 may be arranged as shown in
FIG. 3, for example.
[0075] As shown in FIG. 3, the color processor 32 comprises an
HL/SD density setting unit 40, a tone curve setting unit 42, a
signal rearrangement operating unit 44, a UCR operating unit 46, a
K plate generator 48, a halftone dot % gray balance generator 50, a
halftone dot % setting unit 52, and a color corrector 54. The color
processor 32 generates and outputs color-processed device-dependent
image signals (C, M, Y, K) based on instruction data a1-a7 supplied
from the operator via the input device to the various components
40, 42, 46, 48, 50, 54, 52, and the block dye density values (block
dye density value signals) (C, M, Y) as device-independent image
signals outputted from the DDC/DIC converter 30 (see FIG. 2) and
supplied to the HL/SD density setting unit 40.
[0076] The HL/SD density setting unit 40 normalizes the densities
at the highlight and shadow setting points of the supplied block
dye density values (C, M, Y) with the density setting values of the
instruction data a1 relative to the output device.
[0077] The tone curve setting unit 42 selects a basic tone curve as
one of image conversion functions based on the instruction data a2,
or sets a tone curve by correcting the basic tone curve with a
curve correction coefficient indicated by the instruction data a2.
The tone curve setting unit 42 converts the gradations of the image
signals (C, M, Y) normalized by the HL/SD density setting unit 40
with respect to the image signal C relative to cyan according to
the set tone curve.
[0078] The signal rearrangement operating unit 44 compares the
magnitudes of the image signals (C, M, Y) from the HL/SD density
setting unit 40 to determine a maximum value max and a minimum
value min.
[0079] The UCR operating unit 46 calculates a UCR quantity with
respect to the image signals (C, M, Y) according to the maximum
value max and the minimum value min from the signal rearrangement
operating unit 44 and gray width control data and UCR intensity
data based on the instruction data a3. The UCR quantity is
subtracted from the image signals (C, M, Y) prior to the UCR
process by a subtractor 43. If the UCR process is replaced with a
UCR (Under Color Addition) process, then the UCR intensity data may
be set to a negative value, and the obtained UCR quantity may be
added to the image signals (C, M, Y) prior to the UCA process.
[0080] The K plate generator 48 calculates an image signal K
according to the maximum value max and the minimum value min from
the signal rearrangement operating unit 44 and K plate gray width
control data and K plate generating curve correcting coefficient
data based on the instruction data a4.
[0081] The halftone dot % gray balance generator 50 converts the
image signals (C, M, Y) into halftone dot % signals (C, M, Y),
which turn the image signals (C, M, Y) into gray signals, and also
converts the image signal K into a halftone dot % signal K,
according to gray balance data based on the instruction data
a5.
[0082] The color corrector 54 determines hue signals, lightness
signals, and chroma signals from the image signals (C, M, Y)
supplied from the HL/SD density setting unit 40, and determines
corrective quantities AC, AM, AY, AK for the image signals (C, M,
Y, K) as halftone dot % according to correction coefficients based
on the instruction data a6. The corrective quantities .DELTA.C,
.DELTA.M, .DELTA.Y, .DELTA.K are then added respectively to the
halftone dot % signals (C, M, Y, K) outputted from the halftone dot
% gray balance generator 50 by an adder 51.
[0083] The halftone dot % setting unit 52 further corrects the
halftone dot % signals (C, M, Y, K) to which the corrective
quantities .DELTA.C, .DELTA.M, .DELTA.Y, .DELTA.K have been added,
according to highlight and shadow halftone dot % setting values
based on the instruction data a7.
[0084] The color processor 32 converts the device-independent image
signals (C, M, Y) supplied to the HL/SD density setting unit 40
into the device-dependent image signals (C, M, Y, K) outputted from
the halftone dot % setting unit 52.
[0085] Therefore, the color processor 32 which operates in the
manner described above converts the block dye density values (C, M,
Y) supplied as device-independent image signals from the are
DDC/DIC converter 30 into the device-dependent halftone dot %
signals (C, M, Y, K). The color processor 32 may be constructed as
a single look-up table representing the relationship of conversion
between the block dye density values (C, M, Y) and the halftone dot
% signals (C, M, Y, K). The look-up table thus constructed is
indicated as a color processing LUT 56 by the two-dot-and-dash line
in FIG. 3.
[0086] A process of determining the coefficients Bm of the
polynomial for converting the device-dependent image signals
outputted from the input device such as the scanner 14 or the like
into the device-independent image signals with high accuracy, a
process of selecting an optimum one of the one-dimensional LUTs 16,
18, 20 used to determine the coefficients Bm of the polynomial, and
the input converting process of converting the device-dependent
image signals into the device-independent image signals will be
described below with reference to FIG. 4.
[0087] In step S1 shown in FIG. 4, the scanner 14 scans and reads
an ANSI/IT8.7/1-1993 chart (hereinafter referred to as "IT8 chart")
CT for color reversal films, as an input color target according to
the ANSI (American National Standard Institute) to obtain
device-dependent image signals (R, G, B) for each of patches of the
IT8 chart CT.
[0088] The IT8 chart CT, which is described in pages 56-59 of the
literature 1, will be summarized as follows:
[0089] The IT8 chart CT as an input target is used to convert color
signals from a color reversal film into device-independent signals
(L*, a*, b*), and is arranged as shown in FIG. 5.
[0090] As seen from FIG. 5, the IT8 chart CT has 144 color solid
colors in lines A-L and columns 1-12, primary color scales of C, M,
Y, K, R, G, B in lines A-L and columns 13-19, manufacturer's
inherent colors in lines A-L and columns 20-22, and a lower gray
scale of 22 steps. The color solid colors in the columns 1-12 are
colors selected substantially uniformly from a common color solid
which is common to various real color reversal films.
[0091] The primary color scales in the columns 13-19 are determined
as follows: Gray densities ranging from minimum to maximum
densities are equally divided, producing a K scale. The K scale is
divided to determine primary color scales of C, M, Y. These primary
colors are superposed in combinations of two to determine primary
colors of R (=M+Y), G (=Y+C), B (=C+M).
[0092] In the present embodiment, image signals (R, G, B)
(hereinafter also referred to as "R, G, B values") which are
device-dependent image signals representing the color patches of a
total of 288 colors of the IT8 chart CT are determined by scanning
and reading the IT8 chart CT with the scanner 14.
[0093] In step S2, the image signals (R, G, B) produced by the
scanner 14 are supplied to the one-dimensional LUTs 16, 18, 20,
which generate image signals (Ca, Ma, Ya), image signals (Cb, Mb,
Yb), and image signals (Cc, Mc, Yc), respectively, that are
supplied to the table selecting calculator 22.
[0094] In step S3, the target generator 24 determines block dye
density values (C', M', Y') from colorimetric value signals (X, Y,
Z) of the patches attached to the IT8 chart CT, and supplies the
determined block dye density values (C', M', Y') as target values
to the table selecting calculator 22.
[0095] A process of determining the block dye density values (C',
M', Y') from colorimetric value signals (X, Y, Z) of the patches
attached to the IT8 chart CT in step S3 will be described in detail
below with reference to FIG. 6.
[0096] For determining the block dye density values (C', M', Y')
from colorimetric value signals (X, Y, Z), it is necessary to know
the valuses of the elements Xr, Xg, Xb, Yr, Yg, Yb, Zr, Zg, Zb of
the left matrix on the right side of the equation (7) (the equation
(5)). Specifically, the equations (5) and (7) can be modified
respectively into the following equations (12) and (11). [ R G B ]
= [ X r X g X b Y r Y g Y b Z r Z g Z b ] - 1 .function. [ X Y Z ]
( 11 ) [ 10 - c 10 - m 10 - y ] = [ X r X g X b Y r Y g Y b Z r Z g
Z b ] - 1 .function. [ X Y Z ] ( 12 ) ##EQU7##
[0097] When the calorimetric value signals (X, Y, Z) are
substituted in the equation (12), block dye density values (c, m,
y) on the left side of the equation (12) can be determined from the
equation (12).
[0098] As described above, in order to determine the values of the
elements Xr, Xg, Xb, Yr, Yg, Yb, Zr, Zg, Zb of the matrix, stated
otherwise, in order to determine block dye density values (block
dye density scale), it is necessary to determine imaginary primary
colors R, G, B.
[0099] In a process of setting a color image color reproduction
range in step S11 shown in FIG. 6, a color reproduction range 100
of the color reversal film 12 is set or plotted which is enclosed
by a dotted line on the xy chromaticity diagram according to the
CIE, as shown in FIG. 7. Plotted points 102 in the color
reproduction range 100 are points where a color chart having a
maximum number of (e.g., 3375) color patches that can be expressed
as colors on a color reversal film was measured by the applicant of
the present invention with a colorimeter. It is preferable to
measure the color chart at many points in the vicinity of principal
wavelengths, stated otherwise, those wavelengths including the
colors R, G, B and their complementary colors C, M, Y, for the
purpose of setting block dye density values with greater accuracy.
As well known in the art, an x chromaticity value is calculated
from the colorimetric values X, Y, Z measured by the colorimeter
according to x=X/(X+Y+Z), a y chromaticity value is calculated from
the calorimetric values X, Y, Z according to y=Y/(X+Y+Z), and z
chromaticity value is calculated from the calorimetric values X, Y,
Z according to Z=1-x-y=Z/(X+Y+Z).
[0100] In FIG. 7, the range of an envelope formed by plotted points
104 measured by the applicant represents an actually existing color
range 106.
[0101] In a process of setting straight lines in step S12, as shown
in FIG. 8, a chromaticity point 118 corresponding to a standard
white illuminant is set or plotted on the xy chromaticity diagram,
and three straight lines 111, 112, 113 are established which extend
outwardly from the chromaticity point 118 and pass through the
principal wavelengths relative to the primary colors in the color
reproduction range 100 set in step S11. In the present embodiment,
a chromaticity value (x, y)=(0.3457, 0.3586) of a supplementary
standard illuminant D.sub.50 according to the CIE is used as the
standard white illuminant. Thus, in FIG. 8, the coordinates of the
chromaticity point 118 are represented by (x, y)=(0.3457,
0.3586).
[0102] In a process of determining the vertexes of a triangle
containing the color reproduction range in step S13, as shown in
FIG. 9, vertexes 121, 122, 123 of a triangle 116 containing the
color reproduction range 100 of the color reversal film are
determined on the three straight lines 111, 112, 113. If the
triangle 116 containing the color reproduction range 100 is of a
size such that the area of the triangle 116 is as small as possible
or minimum, then the accuracy of approximation is increased.
[0103] In a process of determining primary colors in step S14, xy
chromaticity values of the vertexes 121, 122, 123 of the triangle
116 are read from the chromaticity diagram shown in FIG. 9), and
determined as chromaticity values of imaginary primary colors R, G,
B. The imaginary primary colors R, G, B are involved because the
chromaticity values of the imaginary primary colors R, G are
present outside the actual color range 106.
[0104] By substituting the values of the primary colors R, G, B for
R=10.sup.-c, B=10.sup.-m, G=10.sup.-y in the equation (6), density
Values c, m, y of the block dyes in the equation (6) are
calculated.
[0105] If the values of the primary colors R, G, B are determined
as xy chromaticity values, then density values c, m, y of the block
dyes can be calculated according to the equations of z=1-x-y,
x=X/(X+Y+Z), y=Y/(X+Y+Z) and the equation (12).
[0106] Based on the chromaticity values of the primary colors R, G,
B determined in step S14 and the chromaticity value of D.sub.50,
values of the elements R.sub.x, R.sub.y, R.sub.z, G.sub.x, G.sub.y,
G.sub.z, B.sub.x, B.sub.y, B.sub.z of the left matrix on the right
side of the equation (8) are determined. As described above with
respect to the equations (9) and (10), the elements Xr, Xg, Xb, Yr,
Yg, Yb, Zr, Zg, Zb of the left matrix on the right side of the
equation (7) can be determined, and hence values of the left
inverse matrix on the right side of the equation (12) can be
determined.
[0107] With the equation (12) set in the target generator 24, it is
possible to determine block dye density values (C', M', Y') from
the colorimetric values (X, Y, Z) of the patches attached to the
IT8 chart CT, and supply the determined block dye density values
(C', M', Y') as target values to the table selecting calculator 22,
in step S3.
[0108] In step S4, the table selecting calculator 22 performs a
regression analysis. In the regression analysis, the relationship
between the input values (Ca, Ma, Ya), (Cb, Mb, Yb), (Cc, Mc, Yc)
as device-dependent image signals and the above target values (C',
M', Y'), i.e., the block dye density values as device-dependent
image signals, is expressed by a polynomial according to the
following equation (13): C ' .times. a .function. ( Ca , Ma , Ya )
= i = 0 n .times. j = 0 i .times. k = 0 i - j .times. A jk
.function. ( i - j - k ) .times. Ca j .times. Ma k .times. Ya ( i -
j - k ) ( 13 ) ##EQU8##
[0109] In the equation (13), the target value C' corresponding to
the input values (Ca, Ma, Ya) is expressed as C'a (Ca, Ma, Ya).
Similarly, in the description which follows, target values M', Y'
corresponding respectively to the input values (Cb, Mb, Yb), (Cc,
Mc, Yc) are expressed as M'a (Cb, Mb, Yb), Y'a (Cc, Mc, Yc),
respectively.
[0110] In the equation (13), A.sub.jk(i-j-k) represents a
coefficient, and n represents the degree of the polynomial and is
determined depending on the required accuracy. In the present
embodiment, the degree n is n=7.
[0111] The equation (13) can be developed in the following equation
(14): C ' .times. a .function. ( Ca , Ma , Ya ) = .times. A 000 + A
001 .times. Ya + A 010 .times. Ma + A 100 .times. Ca + .times. A
002 .times. Ya 2 + A 011 .times. MaYa + A 020 .times. Ma 2 +
.times. A 101 .times. CaYa + A 110 .times. CaMa + A 200 .times. ca
2 + ( 14 ) ##EQU9##
[0112] The target values M', Y' can also be expressed according to
similar equations.
[0113] For reasons of convenience, the equation (14) is replaced
with the following equation (15): C ' .times. a .function. ( Ca ,
Ma , Ya ) = .times. B 0 + B 1 .times. Ya + B 2 .times. Ma + B 3
.times. Ca + B 4 .times. Ya 2 + .times. B 5 .times. MaYa + B 6
.times. Ma 2 + B 7 .times. CaYa + .times. B 8 .times. CaMa + B 9
.times. Ca 2 + ( 15 ) ##EQU10##
[0114] In order to effect a regression analysis on the equation
(15), the equation (15) is replaced with the following equation
(16) where the number of terms of the polynomial is set to n'
{n'=(n+1)(n+2)(n+3)/6=(8.times.9.times.10)/6=120}, C'a is regarded
as an object variable, Xm (m=0, 1, . . . , n'-1) as explanatory
variables, and Bm (m=0, 1, . . . , n'-1) as coefficients: C '
.times. a .function. ( Ca , Ma , Ya ) = .times. B 0 .times. X 0 + B
1 .times. X 1 + .times. + BmXm + .times. + .times. Bn ' - 1 .times.
.times. Xn ' - 1 ( 16 ) ##EQU11##
[0115] A matrix equation for effecting a regression analysis on the
object variable C'a with respect to all the 288 patches of the IT8
chart CT is expressed by the equation (17) shown below. In the
equation (17), a regression analysis is effected on object
variables C'a.sub.0, C'a.sub.1, . . . , C'a.sub.m, . . . ,
C'a.sub.287 corresponding to all the patches of the IT8 chart CT,
thereby determining the coefficients Bm (m=0, 1, . . . , N'-1). [ C
' .times. a 0 C ' .times. a 1 C ' .times. a 287 ] = [ X 00 X 10 Xn
' - 1 0 X 00 X 11 Xn ' - 1 1 X 0287 X 1287 Xn ' - 1 287 ]
.function. [ B 0 B 1 Bn ' - 1 ] ( 17 ) ##EQU12##
[0116] If the coefficients Bm are determined, then the regression
analysis in step S4 is finished.
[0117] After the coefficients Bm are determined, the table
selecting calculator 22 determines a conversion formula, i.e., a
polynomial, for converting the input values (Ca, Ma, Ya) into
target values (C'a, M'a, Y'a) according to the equations (15),
(16). The polynomial uses the linear conversion table 16 as a
one-dimensional LUT.
[0118] Similarly, the table selecting calculator 22 determines a
conversion formula (polynomial) for converting the input values
(Cb, Mb, Yb) into target values (C'b, M'b, Y'b) and a conversion
formula (polynomial) for converting the input values (Cc, Mc, Yc)
into target values (C'c, M'c, Y'c) using the remaining conversion
tables, i.e., the logarithmic conversion table 18 and the luminance
logarithmic conversion table 20, each as one-dimensional LUT.
[0119] In step S6, target values (C'a, M'a, Y'a), (C'b, M'b, Y'b),
(C'c, M'c, Y'c) are calculated with respect to the input values
(Ca, Ma, Ya), (Cb, Mb, Yb), (Cc, Mc, Yc) according to the equation
(14) whose coefficient values are determined.
[0120] In step S7, the calculated target values (C'a, M'a, Y'a),
(C'b, M'b, Y'b), (C'c, M'c, Y'c) are compared with the block dye
density values (C', M', Y') determined as target values in step
S3.
[0121] In step S8, based on the compared result, those values of
the calculated target values (C'a, M'a, Y'a), (C'b, M'b, Y'b),
(C'c, M'c, Y'c) which are closest on the average to the target
values (C', M', Y') are selected, and one of the one-dimensional
LUTs 16, 18, 20 corresponding to the selected values is
determined.
[0122] In step S9, the table selecting calculator 22 switches the
table selector 28 to read output image signals from one of the
one-dimensional LUTs 16, 18, 20 which is determined depending on
the scanner 14 as the input device, holds the coefficients Bm
corresponding to the scanner 14 in the coefficient holder 26, and
sets the polynomial according to the equation (15) that corresponds
to the scanner 14 in the DDC/DIC converter 30.
[0123] When the scanner 14 is actually selected as the input
device, the image processor 15 switches the table selector 28 based
on the result of approximating calculations to select one of the
one-dimensional LUTs 16, 18, 20 corresponding to the scanner 14, in
response to an instruction supplied from the operator via the input
device or automatically according to communications with the
scanner 14, and sets the coefficients Bm, which correspond to the
scanner 14, from the coefficient holder 26 in the polynomial
according to the equation (15) that is set in the DDC/DIC converter
30. The image processor 15 then combines or merges the selected
one-dimensional LUT, the polynomial whose coefficients Bm are set,
and the color processing LUT 56 as the color processor 32 with the
combined LUT generator 34, and sets the merged LUT into the
combined LUT setting unit 36.
[0124] With the merged LUT thus set, it is possible to easily
convert device-dependent image signals (R, G, B) outputted from the
scanner 14 as the input device when a color reversal film 12 as a
subject is read by the scanner 14 into device-dependent image
signals (C, M, Y, K) suitable for use by a printing press as the
output device.
[0125] In the present embodiment, as described above, the image
processor 15 performs the input converting process of converting
device-dependent image signals (R, G, B) supplied from the scanner
14 into device-dependent image signals (C, M, Y) {either one set of
image signals (Ca, Ma, Ya), (Cb, Mb, Yb), (Cc, Mc, Yc)) as
intermediate values using one of the one-dimensional LUTs 16, 18,
20, and thereafter converting the device-dependent image signals
(C, M, Y) as intermediate values into block dye density values (C,
M, Y) as device-independent image signals using the polynomial
according to the equation (15) set in the DDC/DIC converter 30, and
the output converting process of converting the block dye density
values (C, M, Y) as device-independent image signals into
device-dependent image signals (C, M, Y, K) corresponding to the
output device with the color processor 32.
[0126] In the input converting process, device-dependent image
signals (R, G, B) are converted into intermediate device-dependent
image signals (C, M, Y) as intermediate values using one of the
one-dimensional LUTs 16, 18, 20, and thereafter the
device-dependent image signals (C, M, Y) as intermediate values are
converted into block dye density values (C, M, Y) as
device-independent image signals using the polynomial (the equation
(15)} set in the DDC/DIC converter 30. Therefore, the accuracy of
approximation by the polynomial is greatly increased, resulting in
a large increase in the accuracy of conversion by the
polynomial.
[0127] Heretofore, a large-size input profile has been needed to
convert the device-dependent image signals (R, G, B) are converted
into the device-independent image signals (C, M, Y). In the present
embodiment which uses the polynomial, a small-size input profile
may be used because coefficients Bm may be held as a profile. The
accuracy of conversion may be equal to or greater than the
conventional accuracy of conversion by increasing the number of
terms of the polynomial.
[0128] If the input device remains the same, then it is not
necessary to select one of the one-dimensional LUTs 16, 18, 20, but
a single one-dimensional LUT where the value of the polynomial is
most accurate may be fixedly used.
[0129] If the accuracy of conversion does not need to be
substantially high or the approximation by the polynomial is highly
acceptable, then the one-dimensional LUTs 16, 18, 20 may be
dispensed with, and the output signal from the scanner 14 may be
supplied directly to the table selecting calculator 22 and the
DDC/DIC converter 30. This modification has a simpler
arrangement.
[0130] In the present embodiment, the color processor 32 performs
an image processing process based on the block dye density values
(C, M, Y) as device-independent image signals. Therefore, the color
processor 32 can utilize the image processing technique that uses
density-based image signals as conventional image processing
resources.
[0131] The device-independent image signals representing densities
with block dyes have properties similar to conventional density
values and equivalent neutral density values. Therefore, the
device-independent image signals can be handled with ease, and can
highly accurately be converted into colorimetric values X, Y, Z
through simple calculations according to the equation (5).
[0132] In the above embodiment, the device-dependent image signals
are C (cyan), M (magenta), and Y (yellow) signals. However, the
device-dependent image signals may be R (red), G (green), and B
(blue) signals, and the device-independent image signals may be C,
M, Y signals representing densities with block dyes, so that R, G,
B signals and C, M, Y signals outputted from an image input device
such as a digital camera, a scanner, or the like may be handled as
C, M, Y signals representing densities with block dyes.
[0133] In the above embodiment, a color reversal film is used as a
medium carrying a color image. However, if a reflective color print
is used, then an ANSI/IT8.7/2-1993 chart as an input color target
according to the ANSI may be used.
[0134] The above process of converting image signals may be
arranged as an apparatus for performing the converting process.
[0135] FIGS. 10, 11, and 12 show such image signal converting
apparatus 202, 206, 202A, respectively, for performing the
converting process.
[0136] As shown in FIG. 10, the image signal converting apparatus
202 for converting device-dependent image signals into
device-independent image signals has an input converter 204 for
converting device-dependent image signals into device-independent
image signals representing densities with block dyes.
[0137] As shown in FIG. 11, the image signal converting apparatus
206 has an input converter 204 for converting device-dependent
image signals supplied from an input device which reads an image
subject into device-independent image signals representing
densities with block dyes, and an output converter 208 for
converting the device-independent image signals into
device-dependent image signals for an output device.
[0138] As shown in FIG. 12, the image signal converting apparatus
202A has an input converter 204A for converting device-dependent R,
G, B signals device-dependent image signals representing densities
with block dyes.
[0139] The input device is not limited to the scanner 14, but may
be a digital camera. The output device is not limited to a printing
press, but may be a printer, a CRT display, or the like.
[0140] According to the present invention, as described above,
device-dependent image signals are converted into
device-independent image signals representing densities with block
dyes.
[0141] Since the device-independent image signals representing
densities with block dyes have properties similar to conventional
density values and equivalent neutral density values. Therefore,
the image processing resources for processing conventional density
values and equivalent neutral density values may be employed.
[0142] The device-independent image signals can therefore be easily
handled by image processing engineers who have heretofore been
involved in image processing tasks using conventional density
values and equivalent neutral density values.
[0143] Inasmuch as the device-independent image signals
representing densities with block dyes can highly accurately be
converted into colorimetric values through simple calculations
without the need for integral calculations, recent image processing
resources that process calorimetric values can also be employed.
Accordingly, color management is facilitated.
[0144] Although certain preferred embodiments of the present
invention have been shown and described in detail, it should be
understood that various changes and modifications may be made
therein without departing from the scope of the appended
claims.
* * * * *