U.S. patent application number 11/153569 was filed with the patent office on 2005-12-15 for image capturing apparatus, image capturing method, and program.
Invention is credited to Takeuchi, Yoshitaka.
Application Number | 20050275732 11/153569 |
Document ID | / |
Family ID | 35460100 |
Filed Date | 2005-12-15 |
United States Patent
Application |
20050275732 |
Kind Code |
A1 |
Takeuchi, Yoshitaka |
December 15, 2005 |
Image capturing apparatus, image capturing method, and program
Abstract
An object of this invention is to perform, for a photographed
image, image processing which reflects the intention of the user
without photographing again. In order to achieve this object,
photographing data from an image sensor is temporarily stored in a
memory, and an image of the photographing data as a result of
digital development processing is displayed. When it is determined
from the displayed image that the parameters of various image
processes in digital development processing are not proper for the
photographed image, the parameter settings are corrected again.
Then, operation of reading out photographing data from the memory
and performing digital development processing again is executed a
necessary number of times. When an image quality intended by the
photographer is obtained, the photographing data is recorded on a
recording medium.
Inventors: |
Takeuchi, Yoshitaka; (Tokyo,
JP) |
Correspondence
Address: |
MORGAN & FINNEGAN, L.L.P.
3 World Financial Center
New York
NY
10281-2101
US
|
Family ID: |
35460100 |
Appl. No.: |
11/153569 |
Filed: |
June 14, 2005 |
Current U.S.
Class: |
348/231.99 ;
386/E5.072 |
Current CPC
Class: |
H04N 2101/00 20130101;
H04N 1/0044 20130101; H04N 1/00167 20130101; H04N 9/8047 20130101;
H04N 1/6086 20130101; H04N 1/00482 20130101; H04N 5/907 20130101;
H04N 1/00474 20130101; H04N 5/772 20130101; H04N 9/8205 20130101;
H04N 1/00427 20130101; H04N 1/6027 20130101 |
Class at
Publication: |
348/231.99 |
International
Class: |
H04N 005/76; H04N
009/73 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 15, 2004 |
JP |
2004-177345 |
Claims
What is claimed is:
1. An image capturing apparatus comprising: an image sensing device
which senses an object image; a first storage device which stores a
second image signal generated by performing predetermined
processing for a first image signal output from said image sensing
device; an image processing device which performs image processing
for the second image signal to generate a third image signal; a
display device which displays the third image signal; a second
storage device which stores the third image signal; a changing
device which changes a parameter for the image processing of said
image processing device; and a recording instruction device which
issues an instruction to read out the third image signal from said
second storage device and record the third image signal on a
recording medium, wherein every time the parameter is changed by
said changing device, the second image signal is read out from said
first storage device and undergoes the image processing by said
image processing device in accordance with the changed parameter to
newly generate a third image signal, the third image signal is
displayed on said display device and also stored in said second
storage device, and a desired third image signal is read out from
said second storage device and recorded on the recording medium in
accordance with the instruction from said recording instruction
device.
2. The apparatus according to claim 1, wherein the image processing
includes at least a plurality of processes out of white balance
processing of performing white balance adjustment processing for
the second image signal, gain processing of adjusting a level of
the second image signal, low-pass filtering processing of
performing low-pass filtering for an image signal, matrix operation
processing of transforming signal components corresponding to a
plurality of color filters of said image sensing device into a
signal of other chrominance components, contrast processing of
controlling a contrast of an image on the basis of a gamma
characteristic table, gain correction processing for a chrominance
component, hue correction processing of converting a hue, and edge
enhancement processing of enhancing an edge of the image.
3. The apparatus according to claim 2, further comprising a
selection device which selects at least one of the plurality of
processes, wherein said changing device changes a parameter for the
process selected by said selection device.
4. The apparatus according to claim 3, wherein when the process
selected by said selection device is white balance processing, said
changing device changes a white balance control value.
5. The apparatus according to claim 3, wherein when the process
selected by said selection device is gain processing, said changing
device changes a numerical value of the gain processing.
6. The apparatus according to claim 3, wherein when the process
selected by said selection device is low-pass filtering processing,
said changing device changes a characteristic of a low-pass
filter.
7. The apparatus according to claim 3, wherein when the process
selected by said selection device is matrix operation processing,
said changing device changes a matrix value.
8. The apparatus according to claim 3, wherein when the process
selected by said selection device is contrast processing, said
changing device changes the gamma characteristic table.
9. The apparatus according to claim 3, wherein when the process
selected by said selection device is gain correction processing,
said changing device changes a correction gain value.
10. The apparatus according to claim 3, wherein when the process
selected by said selection device is hue correction processing,
said changing device changes a correction value used to convert the
hue.
11. The apparatus according to claim 3, wherein when the process
selected by said selection device is edge enhancement processing,
said changing device changes a numerical value of edge enhancement
processing.
12. An image capturing method comprising: an image sensing step of
sensing an object image; a first storage step of storing in a first
storage device a second image signal generated by performing
predetermined processing for a first image signal obtained in the
image sensing step; an image processing step of performing image
processing for the second image signal to generate a third image
signal; a display step of displaying the third image signal on a
display device; a second storage step of storing the third image
signal in a second storage device; a changing step of changing a
parameter for the image processing in the image processing step;
and a recording instruction step of issuing an instruction to read
out the third image signal from the second storage device and
record the third image signal on a recording medium, wherein every
time the parameter is changed in the changing step, the second
image signal is read out from the first storage device and
undergoes the image processing step in accordance with the changed
parameter to newly generate a third image signal, the third image
signal is displayed on the display device and also stored in the
second storage device, and a desired third image signal is read out
from the second storage device and recorded on the recording medium
in accordance with the instruction in the recording instruction
step.
13. A program causing a computer to execute an image capturing
method defined in claim 12.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a technique of performing
digital development processing including a plurality of image
processes for an image signal photographed by an image sensor, and
recording the image having undergone digital development processing
on a recording medium after the user confirms the image on a
display.
BACKGROUND OF THE INVENTION
[0002] As digital cameras rapidly prevail in the market in recent
years, the role of a photographing device is shifting from
conventional cameras using color films to digital cameras. One of
reasons for this trend is that the digital camera comprises a
function of performing digital development processing including a
plurality of image processes for an image signal photographed by an
image sensor, displaying the image on an accessory image display
such as a TFT monitor immediately after photographing, and allowing
the user to observe the photographing result quickly. An example of
such a digital camera is disclosed in, e.g., Japanese Patent
Laid-Open No. 2003-134530.
[0003] In the film camera, characteristics such as sensitivity,
white balance, and color development are determined by a film
loaded in the camera. To the contrary, the digital camera can
easily change color development of a photographed image and the
like by changing the parameter settings of image processes.
[0004] FIG. 3 is a block diagram showing an example of the
arrangement of a conventional digital camera having a plurality of
color filters.
[0005] These color filters are primary color filters having an
array of R (Red), Gr1 (Green 1), Gr2 (Green 2), and B (Blue), as
shown in FIG. 21. By defining Gr on the R line as Gr1 and Gr on the
B line as Gr2, Gr1 and Gr2 are regarded as different chrominance
components in consideration of a case in which read amplifiers
having different circuit arrangements are used.
[0006] A white balance adjustment unit 320 executes white balance
adjustment processing for respective chrominance component data 304
of a digital chrominance signal which is photographed by an image
sensor 301 having color filters of this array and A/D-converted by
an A/D converter 303.
[0007] In this case, white balance control values for white balance
processing are given as parameters of respective chrominance
components. These control values are multiplied for pixels of each
chrominance component and set so that the ratio of the magnitudes
of chrominance signal components at the achromatic part of an image
becomes R:Gr1:Gr2:B=1:1:1:1.
[0008] In auto white balance adjustment in which a white balance
control value suitable for a photographed image is automatically
obtained from photographed image data, for example, the following
method is adopted.
[0009] The R:B ratio and (R+B):(Gr1+Gr2) ratio are calculated from
adjacent R, Gr1, Gr2, and B in image data, and plotted as
represented by s 2103 on the two-dimensional coordinate system, as
shown in FIG. 19. A combination of R, Gr1, Gr2, and B falling
within a coordinate range 2101 around a locus line 2102 called a
black body radiation locus or CIE day light locus is defined as an
achromatic region. Integral values SumR, SumGr1, SumGr2, and SumB
of the respective chrominance components in the region are
calculated to obtain the SumR:SumGr1:SumGr2:SumB ratio. White
balance control values WbR, WbGr1, WbGr2, and WbB with which the
ratio becomes 1:1:1:1 are calculated by
WbR=(SumGr1+SumGr2)/(2.times.R) (1)
WbGr1=(SumGr1+SumGr2)/(2.times.Gr1) (2)
WbGr2=(SumGr1+SumGr2)/(2.times.Gr2) (3)
WbB=(SumGr1+SumGr2)/(2.times.B) (4)
[0010] In auto white balance adjustment, the white balance control
values are determined for a color temperature of the light source
that is optimal for the target image. White balance adjustment
processing is done by multiplying image data of pixels of R filters
by WbR, those of pixels of Gr1 filters by WbGr1, those of pixels of
Gr2 filters by WbGr2, and those of pixels of B filters by WbB.
[0011] In addition to auto white balance adjustment, there are
proposed preset white balance adjustment and manual white balance
adjustment. In preset white balance adjustment, white balance
adjustment processing is done by giving control values WbR, WbGr1,
WbGr2, and WbB which are constant with respect to the color
temperature of a predetermined light source. In manual white
balance adjustment, an achromatic object is photographed in advance
under the same light source as that used for photographing, and the
white balance control values WbR, WbGr1, WbGr2, and WbB are
calculated from R, Gr1, Gr2, and B data of the photographed
image.
[0012] A level correction unit 322 uniquely gives, regardless of
pixels, the same gain value as a parameter to the respective
chrominance components of the image signal having undergone white
balance processing. The respective signal components are multiplied
by the gain value, thereby correcting the signal level.
[0013] A low-pass filtering unit 324 performs low-pass filtering
processing for the level-corrected image signal.
[0014] The image signal is decomposed into four two-dimensional
planes of R, Gr1, Gr2, and B for pixels corresponding to the
respective color filters. On the plane of each color, "0"s are
assigned and inserted into pixels at pixel array positions at which
no color filter of the color is assigned, as shown in FIG. 22. Each
two-dimensional plane undergoes filtering.
[0015] A matrix processing unit 326 executes, for a signal 325
output from the low-pass filtering unit 324, matrix operation of
replacing each chrominance signal component with another
chrominance signal component. For example, operation of converting
(R, Gr1, Gr2, B) signal components into (Y, Cr, Cb) signal
components of a luminance signal Y and chrominance signals Cr and
Cb is achieved by 4.times.3 matrix transformation: 1 ( Y C r C b )
= ( m 11 m 12 m 13 m 14 m 21 m 22 m 23 m 24 m 31 m 32 m 33 m 34 ) (
R Gr 1 Gr 2 B ) ( A )
[0016] The image signal transformed into (Y, Cr, Cb) signal
components undergoes contrast control processing 328 on the basis
of a gamma table. For example, a characteristic table which
converts a 10-bit input image signal into an 8-bit image signal, as
shown in FIG. 7, is supplied as a parameter to control the tone and
contrast of the image.
[0017] Of image data 329 whose contrast is controlled on the basis
of the gamma table, the Cr and Cb signals are sent to a color gain
correction unit 330 which performs color processing, whereas the Y
signal is sent to an edge enhancement unit 333 which performs
luminance signal processing.
[0018] Of the (Y, Cr, Cb) signal components separated into the
luminance and chrominance signal components, the chrominance signal
components Cr and Cb undergo color gain correction processing by
the color gain correction unit 330. At this time, a color gain
correction value is used as a parameter, and the Cr and Cb values
are multiplied by this gain to adjust the color density. This color
gain correction applies the gain on the Cr--Cb coordinate system,
and the color saturation can be adjusted.
[0019] A hue matrix transformation unit 332 executes 2.times.2
matrix operation for the chrominance signal components Cr and Cb to
adjust the hue. In this case, a 2.times.2 matrix is given as a
parameter, and the hue angle is converted by coordinate
transformation on the (Cr,Cb) two-dimensional coordinate system: 2
( Cr ' Cb ' ) = ( c 11 c 12 c 21 c 22 ) ( Cr Cb ) ( B )
[0020] The luminance signal component Y undergoes edge enhancement
processing by the edge enhancement unit 333. Parameters in the edge
enhancement unit 333 include the number of adjacent pixels to be
referred to for a pixel subjected to edge enhancement, the gain
value of edge enhancement, and an offset value as the threshold
level used to detect an edge to be enhanced.
[0021] For example, assuming that reference pixels in edge
enhancement are eight pixels (a1 to a8) around a target pixel P
whose edge is to be enhanced as shown in FIG. 20, the mean value S
of the nine pixels including the target pixel P is calculated: 3 S
= ( P + k = 1 n ak ) / 9
[0022] The difference between the target pixel and the mean value S
is calculated, and when the difference exceeds the offset value th,
the difference is multiplied by the gain value Gain of edge
enhancement and the product is added to the original target pixel
P, thereby achieving edge enhancement processing:
P'=P+(P-S-th).multidot.Gain ((P-S).gtoreq.th)
[0023] With these parameters, the degree of edge enhancement
processing on the image is adjusted. Edge enhancement can be made
strong by a larger gain value and weak by a smaller gain value.
Edge enhancement can be made weak by a larger offset value and
strong by a smaller gain value.
[0024] The image signal (Y, Cr, Cb) having undergone digital
development processing including various image processes is
formatted by a formatting unit 309 into an image file of a
general-purpose image format such as a JPEG file. The image file is
recorded by an image recording unit 317 on various recording media
(e.g., compact flash.RTM. memory card) removable from the camera
main body.
[0025] From the above description, image processing which reflects
the intention of the user of the digital camera on various
photographing conditions can be realized by setting before
photographing the parameters of various image processes when
digital development processing is executed for a photographed
image. If, however, an image of an image quality which does not
reflect the intention of the photographer is photographed due to a
change in photographing conditions during photographing, parameters
must be set again to execute photographing again. Also, whether set
parameters are optimal is not known until a photographed image is
confirmed, and photographing may be repeated, missing a
photographing scene intended by the photographer.
SUMMARY OF THE INVENTION
[0026] The present invention has been made to overcome the
conventional drawbacks, and has as its object to perform, for a
photographed image, image processing which reflects the intention
of the user without photographing again.
[0027] To solve the above problem and achieve the above object,
according to the first aspect of the present invention, an image
capturing apparatus is comprising an image sensing device which
senses an object image, a first storage device which stores a
second image signal generated by performing predetermined
processing for a first image signal output from the image sensing
device, an image processing device which performs image processing
for the second image signal to generate a third image signal, a
display device which displays the third image signal, a second
storage device which stores the third image signal, a changing
device which changes a parameter for the image processing of the
image processing device, and a recording instruction device which
issues an instruction to read out the third image signal from the
second storage device and record the third image signal on a
recording medium, wherein every time the parameter is changed by
the changing device, the second image signal is read out from the
first storage device and undergoes the image processing by the
image processing device in accordance with the changed parameter to
newly generate a third image signal, the third image signal is
displayed on the display device and also stored in the second
storage device, and a desired third image signal is read out from
the second storage device and recorded on the recording medium in
accordance with the instruction from the recording instruction
device.
[0028] According to the second aspect of the present invention, an
image capturing method is comprising an image sensing step of
sensing an object image, a first storage step of storing in a first
storage device a second image signal generated by performing
predetermined processing for a first image signal obtained in the
image sensing step, an image processing step of performing image
processing for the second image signal to generate a third image
signal, a display step of displaying the third image signal on a
display device, a second storage step of storing the third image
signal in a second storage device, a changing step of changing a
parameter for the image processing in the image processing step,
and a recording instruction step of issuing an instruction to read
out the third image signal from the second storage device and
record the third image signal on a recording medium, wherein every
time the parameter is changed in the changing step, the second
image signal is read out from the first storage device and
undergoes the image processing step in accordance with the changed
parameter to newly generate a third image signal, the third image
signal is displayed on the display device and also stored in the
second storage device, and a desired third image signal is read out
from the second storage device and recorded on the recording medium
in accordance with the instruction in the recording instruction
step.
[0029] Other objects and advantages besides those discussed above
shall be apparent to those skilled in the art from the description
of a preferred embodiment of the invention which follows. In the
description, reference is made to accompanying drawings, which form
a part hereof, and which illustrate an example of the invention.
Such example, however, is not exhaustive of the various embodiments
of the invention, and therefore reference is made to the claims
which follow the description for determining the scope of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a block diagram showing the arrangement of a
digital camera as an example of an image capturing apparatus
according to the first embodiment of the present invention;
[0031] FIG. 2 is a block diagram showing the arrangement of a
digital camera as an example of an image capturing apparatus
according to the second embodiment of the present invention;
[0032] FIG. 3 is a block diagram showing an example of the
arrangement of a conventional digital camera;
[0033] FIG. 4 is a view showing the rear surface of the digital
camera according to the first embodiment of the present
invention;
[0034] FIG. 5 is a view showing an information display in FIG.
4;
[0035] FIG. 6 is a graph showing a gamma characteristic;
[0036] FIG. 7 is a graph showing a gamma characteristic;
[0037] FIG. 8 is a view showing the rear surface of the digital
camera according to the second embodiment of the present
invention;
[0038] FIG. 9 is a view showing an information display in FIG. 8
which displays an image process menu;
[0039] FIG. 10A is a view showing the information display in FIG. 8
which displays a development result when using the standard
parameter of the white balance;
[0040] FIG. 10B is a view showing a display of the information
display in FIG. 8 when the parameter of the white balance is to be
switched;
[0041] FIG. 11 is a view showing a display of the information
display in FIG. 8 when the parameter of level correction is to be
switched;
[0042] FIG. 12 is a view showing a display of the information
display in FIG. 8 when the parameter of the low-pass filter
characteristic is to be switched;
[0043] FIG. 13 is a view showing a display of the information
display in FIG. 8 when the parameter of the color conversion matrix
is to be switched;
[0044] FIG. 14 is a view showing a display of the information
display in FIG. 8 when the parameter of the gamma characteristic is
to be switched;
[0045] FIG. 15 is a view showing a display of the information
display in FIG. 8 when the parameter of color gain correction is to
be switched;
[0046] FIG. 16 is a view showing a display of the information
display in FIG. 8 when the parameter of hue adjustment is to be
switched;
[0047] FIG. 17 is a view showing a display of the information
display in FIG. 8 when the parameter of edge enhancement is to be
switched;
[0048] FIG. 18 is a graph showing a correspondence table of the
chromaticity coordinate X and color temperature for obtaining the
white balance;
[0049] FIG. 19 is a graph showing the black body radiation locus or
CIE day light locus and the achromatic region on the chromaticity
coordinate system for obtaining the white balance;
[0050] FIG. 20 is a view showing the relationship between a target
pixel and adjacent pixels when edge enhancement processing is
performed;
[0051] FIG. 21 is a view for explaining the array of color filters
on an image sensor in the image capturing unit of a digital camera;
and
[0052] FIG. 22 is a view for explaining a process for each
chrominance component of image data.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] Preferred embodiments of the present invention will be
described below with reference to the accompanying drawings.
First Embodiment
[0054] FIG. 1 is a block diagram showing the arrangement of a
digital camera as an example of an image capturing apparatus
according to the first embodiment of the present invention. In the
first embodiment, a digital camera is employed as an example of the
image capturing apparatus, but the image capturing apparatus
according to the first embodiment can also be implemented by a
digital video camera, a digital camera-equipped apparatus
(including a digital camera-equipped cell phone), or the like.
[0055] In the first embodiment, the result of developing a
photographed image by a digital development unit is confirmed on an
image display unit, and the parameters of one or more image
processes in the digital development unit are switched to develop
the image again. After the user confirms on the image display unit
that the redevelopment result is a desired development result, the
image is recorded on a recording medium by a recording unit in
response to an instruction from a recording instruction unit.
[0056] In FIG. 1, reference numeral 101 denotes an image sensor
serving as an image sensing device having a plurality of color
filters; 103, an A/D converter which converts a first image signal
102 output from the image sensor 101 into a second image signal 104
serving as digital data; 105, a first memory which stores the
A/D-converted second image signal 104; 106, a digital development
unit which performs digital development processing including a
plurality of image processes; 107, a third image signal (color
difference signal) which is generated by digital development
processing; 109, a formatting unit which formats a signal 108
(luminance signal) into an image file; 111, an image display unit
which displays filed data 110 of the third image signal; 112, a
second memory which holds the filed data 110 of the third image
signal; 117, a recording unit which records filed data 116 of the
third image signal read out from the second memory 112; and 113, a
recording instruction unit which outputs a recording instruction
signal 114 for reading out the filed data of the third image signal
from the second memory 112 and recording the filed data on the
recording medium 117 removable from the camera.
[0057] The digital development unit 106 which performs digital
development processing comprises a white balance adjustment unit
120, a level correction unit 122 which adjusts the image signal
level, a low-pass filtering unit 124, a matrix operation unit 126
which converts the array of chrominance components, a gamma
characteristic table conversion unit 128 which controls the
contrast, a color gain correction unit 130 which multiplies
chrominance components by a gain, a hue adjustment unit 132 which
converts the hue, and an edge enhancement unit 133.
[0058] Reference numeral 134 denotes a parameter switching
instruction unit which outputs an instruction signal 137 for
switching the parameters of these image processes, and outputs an
instruction signal 135 for reading out a second image signal 136
from the first memory 105 and performing development again. The
parameter of the white balance adjustment unit 120 is switched by a
signal 137a contained in the parameter switching instruction signal
137. The parameter of the level correction unit 122 is switched by
a signal 137b; that of the low-pass filtering unit 124, by a signal
137c; that of the matrix operation unit 126, by a signal 137d; that
of the gamma characteristic conversion unit 128, by a signal 137e;
that of the color gain correction unit 130, by a signal 137f; that
of the hue adjustment unit 132, by a signal 137g; and that of the
edge enhancement unit 133, by a signal 137h.
[0059] The image signal 102 which is obtained from the image sensor
101 having color filters of four colors (R, G1, G2, B) and is made
up of four chrominance components (R, G1, G2, B), similar to the
prior art, is converted into the second digital image signal 104 by
the A/D converter 103.
[0060] The digital image signal 104 is sent to the digital
development unit 106 when subsequent photographing is done by
pressing an image adjustment switch 404 on a rear surface 400 of
the digital camera shown in FIG. 4. The digital image signal 104 is
also sent to and held in the first readable memory 105 in response
to the redevelopment instruction signal 135 (to be described
later).
[0061] The digital development unit 106 performs the first digital
development processing for the image signal 104 after
photographing. At this time, parameters in various image processes
are set to default values.
[0062] In the first embodiment, processes by the digital
development unit 106 include various image processes by the white
balance adjustment unit 120, the level correction unit 122 which
adjusts the image signal level, the low-pass filtering unit 124,
the matrix operation unit 126 which converts the array of
chrominance components, the gamma characteristic table conversion
unit 128 which controls the contrast, the color gain correction
unit 130 which multiplies chrominance components by a gain, the hue
adjustment unit 132 which converts the hue, and the edge
enhancement unit 133. A case will be described in which
redevelopment is executed by changing as a development parameter a
combination of the parameters of the gamma characteristic table
conversion unit 128, color gain correction unit 130, and edge
enhancement unit 133.
[0063] FIG. 6 is a graph showing a gamma characteristic table
according to the first embodiment. The abscissa represents a 10-bit
input level of the processing unit, and the ordinate represents an
8-bit output level.
[0064] The curve of a table 602 exhibits a characteristic for
outputting an image of a high contrast with respect to a default
table 601. The curve of a table 603 exhibits a characteristic for
outputting an image of a low contrast. The gamma characteristic
table as a parameter is switched between the three tables
"default", "high contrast", and "low contrast" in response to the
parameter switching instruction command 137e.
[0065] The color gain correction unit 130 has a default color gain
of x1.0, and multiplies chrominance components by 1.2 to increase
the color saturation of a development result in a process of high
color density and by 0.8 to decrease the color saturation of a
development result in a process of low color density. The color
gain correction table as a parameter is switched between the three
tables "default", "high color density", and "low color density" in
accordance with the parameter switching instruction command
137f.
[0066] The edge enhancement unit 133 has a default gain value of
x1.0 in edge enhancement described in the prior art, and changes
the degree of edge enhancement to x2.0 for strong edge enhancement
and x0.0 for weak edge enhancement. The offset value is set to 4.0
as a default value, and 2.0 as a setting for strong edge
enhancement. The edge enhancement table as a parameter is switched
between the three tables "default" (gain value=1.0, offset
value=4.0), "strong" (gain value=2.0, offset value=2.0), and "weak
(edge enhancement OFF)" (gain value=0.0, offset value=arbitrary
value) in accordance with the parameter switching instruction
command 137h.
[0067] By combining these three image processing tables, a
combination of "gamma characteristic table.fwdarw.default", "color
gain correction table.fwdarw.default", and "edge enhancement
table.fwdarw.default" is defined as "development parameter 1".
Also, a combination of "gamma characteristic table.fwdarw.high
contrast", "color gain correction table.fwdarw.high color density",
and "edge enhancement table.fwdarw.strong" is defined as
"development parameter 2". A combination of "gamma characteristic
table.fwdarw.low contrast", "color gain correction table.fwdarw.low
color density", and "edge enhancement table.fwdarw.weak (edge
enhancement OFF)" is defined as "development parameter 3".
[0068] Characteristic operation of the first embodiment will be
explained.
[0069] As described above, when photographing is done by pressing
the image adjustment switch 404 on the rear surface of the digital
camera shown in FIG. 4, the image data 104 in FIG. 1 undergoes
digital development processing by the digital development unit 106
and at the same time is sent to and held in the first memory 105.
The digital development unit 106 executes the first digital
development processing at "development parameter 1", i.e., in the
default parameter setting state after photographing.
[0070] At this time, the third image signals 107 (color difference
signal) and 108 (luminance signal) as development results are
formatted into a JPEG file by the formatting unit 109, and sent to
the second memory 112.
[0071] The JPEG-filed third image signals are also sent to the
display unit 111, and a development result image 502 is displayed
on a display unit 501 together with a development parameter
selection table 503, as shown in FIG. 5.
[0072] By pressing a cross key 412 on the rear surface of the
camera shown in FIG. 4, the development parameter to be selected is
switched from "development parameter 1" to "development parameter
2". With this operation, the switching instruction unit 134 in FIG.
1 outputs the parameter switching instruction signal 137. The
parameter setting value of the gamma characteristic table is
switched from "default" to "high contrast" by the signal 137e, that
of the color gain correction unit is switched from "default" to
"high color density" by the signal 137f, and that of the edge
enhancement unit is switched from "default" to "strong" by the
signal 137h.
[0073] The second image signal stored in the first memory is read
out in response to the redevelopment instruction signal 135 output
from the switching instruction unit 134, and undergoes digital
development processing again by the digital development unit
106.
[0074] The redeveloped third image signals 107 (color difference
signal) and 108 are formatted into a JPEG file by the formatting
unit 109. The filed image signal 110 is sent to the second memory
112, and written over the image file having undergone digital
development processing at "development parameter 1" or stored in
another area. At the same time, the filed image signal 110 is sent
to the display unit 111, replaces image data of the digital
development processing result at "development parameter 1", and is
displayed as image data of the digital development processing
result at "development parameter 2".
[0075] By pressing the cross key 412 on the rear surface of the
camera shown in FIG. 4, the development parameter to be selected is
switched from "development parameter 2" to "development parameter
3". With this operation, the switching instruction unit 134 in FIG.
1 outputs the parameter switching instruction signal 137. The
parameter setting value of the gamma characteristic table is
switched from "high contrast" to "low contrast" by the signal 137e,
that of the color gain correction unit is switched from "high color
density" to "low color density" by the signal 137f, and that of the
edge enhancement unit is switched from "strong" to "weak (edge
enhancement OFF)" by the signal 137h. Similar to the above case,
digital development processing is performed again, and image data
of the development result at "development parameter 3" is stored in
the second memory 112 and displayed on the image display unit 111
instead of the image data at "development parameter 2".
[0076] By pressing the cross key 412 on the rear surface of the
camera shown in FIG. 4, the development parameter is returned to
the default state of development at "development parameter 1".
[0077] Also, by pressing a cross key 409 on the rear surface of the
camera shown in FIG. 4, the development parameter can be switched
in a reverse order.
[0078] By switching the development parameter, the camera user
observes an image 402 of a digital development processing result
that appears on the image display unit 111, and he selects a
desired development parameter and presses a parameter selection
button 408 shown in FIG. 4. With this operation, the recording
instruction unit 113 outputs the recording instruction signal 114,
and data of the image file of a digital development processing
result at the selected development processing is read out from the
second memory 112 and recorded on the recording medium 117.
[0079] By switching the development parameter in this manner, the
camera user compares on the image 402 displayed on a monitor 401
the development result of "development parameter 1" as a default
setting, the development result of "development parameter 2" at
which a photographed image of a higher contrast, higher color
density, and stronger edge enhancement in comparison with the
default settings can be directly used without any post-processing,
and the development result of "development parameter 3" at which an
image of a lower contrast, lower color density, and no edge
enhancement in comparison with the default setting can be used as a
material at a high degree of freedom of post-processing. The camera
user can select and record an optimal image.
[0080] Even if an image of an image quality which does not reflect
the intention of the photographer is photographed due to a change
in photographing conditions during photographing, the development
parameter can be switched and set again to perform digital
development processing. Whether the set parameter is optimal can be
easily confirmed, photographing need not be repeated, and an
optimal photographing result can always be implemented without
missing a photographing scene intended by the photographer.
[0081] In the first embodiment, the development parameter is a
combination of the gamma characteristic table, color gain
correction, and edge enhancement processing. In addition to this,
the color development characteristic of the image of a development
result can also be switched using the white balance adjustment unit
120, matrix operation unit 126, and hue adjustment unit 132.
Exposure can also be corrected using the level correction unit 122,
or the image quality can also be switched by switching the
characteristic of the low-pass filtering unit 124.
Second Embodiment
[0082] The second embodiment of the present invention will be
described below.
[0083] FIG. 2 is a block diagram showing the arrangement of a
digital camera as an example of an image capturing apparatus
according to the second embodiment of the present invention. In the
second embodiment, a digital camera is employed as an example of
the image capturing apparatus, but the image capturing apparatus
according to the second embodiment can also be implemented by a
digital video camera, a digital camera-equipped apparatus
(including a digital camera-equipped cell phone), or the like.
[0084] In the second embodiment, the result of developing a
photographed image by a digital development unit is confirmed on an
image display unit, one of a plurality of types of image processes
in the digital development unit is selected, and the parameters of
the selected process are switched to perform development again.
After the user confirms on the image display unit that the
redevelopment result is a desired development result, the result is
recorded on a recording medium by a recording unit in accordance
with an instruction from a recording instruction unit.
[0085] In FIG. 2, reference numeral 201 denotes an image sensor
serving as an image sensing device having a plurality of color
filters; 203, an A/D converter which converts a first image signal
202 output from the image sensor 201 into a second image signal 204
serving as digital data; 205, a first memory which stores the
second image signal 204; 206, a digital development unit which
performs digital development processing including a plurality of
image processes; 209, a formatting unit which formats, into an
image file, third image signals 207 (color difference signal) and
208 (luminance signal) which are generated by digital development
processing; 211, an image display unit which displays filed data
210 of the third image signals; 212, a second memory which holds
the filed data 210 of the third image signals; 217, a recording
unit which records filed data 216 of the third image signals read
out from the second memory 212; and 213, a recording instruction
unit which outputs a recording instruction signal 214 for reading
out the filed data of the third image signals from the second
memory 212 and recording the filed data on the recording medium 217
removable from the camera.
[0086] The digital development unit 206 which performs digital
development processing comprises a white balance adjustment unit
220, a level correction unit 222 which adjusts the image signal
level, a low-pass filtering unit 224, a matrix operation unit 226
which converts the array of chrominance components, a gamma
characteristic table conversion unit 228 which controls the
contrast, a color gain correction unit 230 which multiplies
chrominance components by a gain, a hue adjustment unit 232 which
converts the hue, and an edge enhancement unit 233.
[0087] Reference numeral 239 denotes an image process selection
instruction unit which outputs an instruction signal 240 for
selecting from these image processes an image process whose
parameters are to be switched; 238, an image process selection unit
which selects in accordance with the selection instruction signal
240 an image process whose parameters are to be switched; and 234,
a parameter switching instruction unit which outputs an instruction
signal 237 for switching parameters, and outputs an instruction
signal 235 for reading out a second image signal 236 from the first
memory 205 and performing redevelopment.
[0088] The parameter of the white balance adjustment unit 220 is
switched by a signal 237a contained in the parameter switching
instruction signal 237. The parameter of the level correction unit
222 is switched by a signal 237b; that of the low-pass filtering
unit 224, by a signal 237c; that of the matrix operation unit 226,
by a signal 237d; that of the gamma characteristic conversion unit
228, by a signal 237e; that of the color gain correction unit 230,
by a signal 237f; that of the hue adjustment unit 232, by a signal
237g; and that of the edge enhancement unit 233, by a signal
237h.
[0089] The image signal 202 which is obtained from the image sensor
201 having color filters of four colors (R, G1, G2, B) and is made
up of four chrominance components (R, G1, G2, B), similar to the
prior art, is converted into the second digital image signal 204 by
the A/D converter 203.
[0090] The digital image signal 204 is sent to the digital
development unit 206 when subsequent photographing is done by
pressing an image adjustment switch 804 on a rear surface 800 of
the digital camera shown in FIG. 8. The digital image signal 204 is
also sent to and held in the first readable memory 205 in response
to the redevelopment instruction signal 235 (to be described
later).
[0091] The digital development unit 206 performs the first digital
development processing for the image signal 204 after
photographing. At this time, parameters in various image processes
are set to default values.
[0092] In the second embodiment, processes by the digital
development unit 206 include various image processes by the white
balance adjustment unit 220, the level correction unit 222 which
adjusts the image signal level, the low-pass filtering unit 224,
the matrix operation unit 226 which converts the array of
chrominance components, the gamma characteristic table conversion
unit 228 which adjusts the contrast, the color gain correction unit
230 which multiplies chrominance components by a gain, the hue
adjustment unit 232 which converts the hue, and the edge
enhancement unit 233. An image process menu switch 813 in FIG. 8 is
pressed before or after photographing to display the types of image
processes on the display screen. The type of image process is
selected by pressing cross keys 809 to 812, and then a set button
808 is pressed to determine from a plurality of image processes an
image process whose parameter settings are to be switched.
[0093] With this operation, the third image signals 207 (color
difference signal) and 208 (luminance signal) having undergone the
first digital development processing at default parameters after
photographing are converted into image data of the JPEG file format
by the formatting unit 209. The image signal 210 is stored in the
second memory 212, and at the same time, is sent to and displayed
on the display unit 211. At this time, the image display unit 211
also displays the parameter setting state of the selected image
process together. The image signal 210 is a result of the first
digital development processing, and the default parameter setting
values of the selected image process are displayed as "standard"
setting values.
[0094] Characteristic operation of the second embodiment will be
explained separately for cases in which respective image processes
are selected.
[0095] Of image processes, an image process of switching the
parameter setting value of the white balance adjustment unit 220
will be explained.
[0096] An image process of switching the white balance parameter
setting is selected from image processes in digital development
processing by using the image process menu switch 813 and cross
keys 809 to 812 in FIG. 8, and is determined by pressing the set
button 808. Then, as shown in FIG. 10A, a display 1001 displays an
image 1002 of the result of the first digital development
processing at "standard" setting values, and a chromaticity
coordinate value 1005 representing a point set as a white point of
the white balance.
[0097] R, Gr1, Gr2, and B values serving as the basis of the
chromaticity coordinate value are calculated from reciprocals of
WbR, WbGr1, WbGr2, and WbB used for white balance control:
R=1/WbR (5)
Gr1=1/WbGr1 (6)
Gr2=1/WbGr2 (7)
B=1/WbB (8)
[0098] In order to allow the user to easily grasp the position of a
white point, chromaticity coordinates X and Y are represented by
the color temperature while the abscissa X (1004) represents the
black body radiation locus or day light locus. In order to easily
execute operation within the camera at a high speed, the Red-Blue
direction, i.e., color temperature direction is given by
addition/subtraction operation:
X=(B-R)/Yi (9)
[0099] The relationship between X and the color temperature is
prepared in advance as an X-color temperature table as shown in
FIG. 18.
[0100] Similarly, the ordinate Y (1003) is defined by an operation
which represents the Green-Magenta direction:
Y={(R+B)-(Gr1+Gr2)}/Yi (10)
[0101] Yi is used to normalize the color coordinates X and Y by the
luminance component, and may be given by, e.g., the following
equation defined by the NTSC standard: 4 Yi = 0.299 .times. R +
0.587 .times. ( Gr1 + Gr2 ) / 2 + 0.144 .times. B ( 11 )
[0102] In FIG. 10A, the chromaticity coordinates X and Y obtained
from a white balance control value used in an image process in the
first digital development processing after photographing are
displayed on the display 1001 together with an image of the
development result. White balance adjustment at this time can adopt
the control value of auto white balance adjustment, preset white
balance adjustment, or manual white balance adjustment which have
been described in the prior art.
[0103] Then, the photographer changes the color reproduction of an
image of the digital development processing result upon white
balance adjustment processing by changing the parameter setting
value. For this purpose, the photographer moves the white point on
the chromaticity coordinate system from the default coordinates
(X,Y) to target white point coordinates (X',Y') by using the cross
keys 809 to 812. In FIG. 10B, represents default chromaticity
coordinates (X,Y) (1005), and .star. represents target chromaticity
coordinates (X',Y') (1006). The cross keys 810 and 811 are used to
move the coordinates at constant intervals in plus and minus
directions along the Red-Blue (color temperature) direction. The
cross keys 809 and 812 are used to move the coordinates at constant
intervals in plus and minus directions along the Green-Magenta
direction.
[0104] After the chromaticity coordinates are moved to a target
point, the photographer presses the set button 808. Then, the
parameter switching instruction unit 234 in FIG. 2 outputs a signal
for reading out the second image signal 236 from the first memory
205 and the signal 237a for switching the parameter setting value,
and redevelopment processing starts.
[0105] As is apparent from equations (1) to (4) in the prior art,
control values as new parameters in white balance adjustment
processing are based on (Gr1+Gr2)/2. Hence, (Gr1+Gr2)/2=1.0 is
substituted into equation (10), and (X',Y') is substituted into
equations (9) and (10) to obtain an R':Gr':B' ratio corresponding
to (X',Y'). Consequently, new control values WbR', WbGr1', WbGr2',
and WbB' are attained as parameters of white balance adjustment
processing that are changed from equations (5) to (8). Digital
development processing is executed again by using these parameters,
and the image file 210 of the development result is sent to and
stored in the second memory 212, and displayed on the display unit
211.
[0106] By repeating this operation, the photographer confirms image
data of a desired color reproduction result on the image 1002
played back on the display unit 211, and then presses a recording
instruction switch 805 in FIG. 8. In response to this, the
recording instruction unit 213 outputs the recording instruction
signal 214, and the image file stored in the second memory 212 is
sent to the recording unit 217 and recorded on the recording
medium.
[0107] In this way, an image of a color reproduction desired by the
photographer can be obtained by recording an image which is
developed again after changing the "standard" setting values of the
parameters of white balance processing operation.
[0108] In the above description, development is executed again by
setting a target value of the white point of the white balance with
the cross keys 809 to 812 and changing the parameter.
Alternatively, an image of a redevelopment result may be displayed
by performing development again after changing the white balance
control value on the basis of the numerical values of the
coordinates (X',Y') (1006) which are moved every time one of the
cross keys 809 to 812 is pressed.
[0109] Of image processes, an image process of switching the
parameter setting value of the level correction unit 222 will be
explained.
[0110] An image process of switching the level correction parameter
setting is selected from image processes in digital development
processing by using the image process menu switch 813 and cross
keys 809 to 812 in FIG. 8, and is determined by pressing the set
button 808. Then, as shown in FIG. 11, a display 1101 displays an
image 1102 of the result of the first digital development
processing at "standard" setting values, and a level correction
gain value 1103. The result of the first digital development
processing is the result of photographing under "standard" correct
exposure, and thus "x1.0" is displayed as shown in FIG. 11.
[0111] The display sequentially changes to "x1.2", "x1.4", . . . by
pressing the cross key 809, and "x0.8", "x0.6", . . . by pressing
the cross key 812. When a desired gain value is displayed, the
photographer presses the set button 808 to update the parameter
setting value of the level correction unit 222 to the current gain
value by the signal 237b. At this time, digital development
processing is performed again using this parameter, and the image
file 210 of the development result is sent to and stored in the
second memory 212, and displayed on the display unit 211.
[0112] By repeating this operation, the photographer confirms image
data of a desired exposure on the image 1102 played back on the
display unit 211, and then presses the recording instruction switch
805 in FIG. 8. In response to this, the recording instruction unit
213 outputs the recording instruction signal 214, and the image
file stored in the second memory 212 is sent to the recording unit
217 and recorded on the recording medium.
[0113] An image of an exposure desired by the photographer can,
therefore, be attained by recording an image which is developed
again after changing the "standard" setting value of the parameter
of level correction processing.
[0114] In the above description, development is executed again by
setting a target gain value of level correction with the cross keys
809 and 812 and changing the parameter. Alternatively, images of
redevelopment results may be sequentially displayed by performing
development again at a level correction gain value changed every
time either the cross key 809 or 812 is pressed.
[0115] Also, the gain value is set to the notation of multiples
"x1.0", "x1.2" . . . . Alternatively, exposure control based on the
EV value may be adopted to express "+1.0", "+2.0", . . . for
"standard"="0". For example, an image signal is multiplied by
double the gain at "+1.0", and 2.sup.1/3 the gain at "+1/3".
[0116] Of image processes, an image process of switching the
parameter setting value of the low-pass filtering unit 224 will be
explained.
[0117] An image process of switching the parameter setting of the
low-pass filter is selected from image processes in digital
development processing by using the image process menu switch 813
and cross keys 809 to 812 in FIG. 8, and is determined by pressing
the set button 808. Then, as shown in FIG. 12, a display 1201
displays an image 1202 of the result of the first digital
development processing at "standard" setting values, and a low-pass
filter characteristic 1203. The result of the first digital
development processing exhibits that a "1-2-1" 3-tap filter is
employed as "standard" in both the horizontal and vertical
directions.
[0118] The display sequentially changes to "LPF2: 1-2-5-2-1 in the
horizontal direction and 1-2-5-2-1 in the vertical direction" and
"LPF3: 1-0-3-0-1 in the horizontal direction and 1-2-1 in the
vertical direction" by pressing the cross key 812. When a desired
image is obtained, the photographer presses the set button 808 to
update the parameter setting value to the current low-pass filter
by the signal 237c. At this time, digital development processing is
performed again using this parameter, and the image file 210 of the
development result is sent to and stored in the second memory 212,
and displayed on the display unit 211.
[0119] By repeating this operation, the photographer confirms a
desired image on the image 1202 played back on the display unit
211, and then presses the recording instruction switch 805 in FIG.
8. In response to this, the recording instruction unit 213 outputs
the recording instruction signal 214, and the image file stored in
the second memory 212 is sent to the recording unit 217 and
recorded on the recording medium.
[0120] In this fashion, an image of a resolution desired by the
photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of the low-pass filter. Further, generation of a false
color in an image can also be dealt with by switching the
characteristic of the low-pass filter.
[0121] In the above description, development is executed again by
selecting a target characteristic of the low-pass filter with the
cross keys 809 and 812 and changing the parameter. Alternatively,
images of redevelopment results may be sequentially displayed by
performing development again with a low-pass filter characteristic
changed every time either the cross key 809 or 812 is pressed.
[0122] Of image processes, an image process of switching the
parameter setting value of the matrix operation unit 226 for
converting the array of chrominance components will be
explained.
[0123] An image process of switching the parameter setting of the
color matrix is selected from image processes in digital
development processing by using the image process menu switch 813
and cross keys 809 to 812 in FIG. 8, and is determined by pressing
the set button 808. Then, as shown in FIG. 13, a display 1301
displays an image 1302 of the result of the first digital
development processing at "standard" setting values. In addition,
an image 1303 exhibits that the results of the first digital
development processing are the results of development based on
"matrix 1 (standard)".
[0124] The display sequentially changes to "matrix 2", "matrix 3",
and "matrix 4" by pressing the cross key 812. As each of the matrix
tables, there is prepared a matrix table having 4.times.3 element
values m11 to m34 so as to change color reproduction in equation
(A) described in the prior art. When a desired matrix table is set,
the photographer presses the set button 808 to update the parameter
setting value to the current color matrix table by the signal 237d.
At this time, digital development processing is performed again
using this parameter, and the image file 210 of the development
result is sent to and stored in the second memory 212, and
displayed on the display unit 211.
[0125] By repeating this operation, the photographer confirms image
data of a desired color reproduction on the image 1302 played back
on the display unit 211, and then presses the recording instruction
switch 805 in FIG. 8. In response to this, the recording
instruction unit 213 outputs the recording instruction signal 214,
and the image file stored in the second memory 212 is sent to the
recording unit 217 and recorded on the recording medium.
[0126] Consequently, an image of a color reproduction desired by
the photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of the color matrix.
[0127] In the above description, development is executed again by
selecting a target one of color matrix tables with the cross keys
809 and 812 and changing the parameter. Alternatively, images of
redevelopment results may be sequentially displayed by performing
development again on the basis of a color matrix table changed
every time either the cross key 809 or 812 is pressed.
[0128] The numerical values m11 to m34 of the respective elements
of the color matrix can also be individually selected with the
cross keys 809 to 812 and set button 808 to change the magnitude of
each numerical value and perform development again.
[0129] Of image processes, an image process of switching the
parameter setting value of the gamma characteristic table
conversion unit 228 for controlling the contrast will be
explained.
[0130] An image process of switching the parameter setting of the
gamma table is selected from image processes in digital development
processing by using the image process menu switch 813 and cross
keys 809 to 812 in FIG. 8, and is determined by pressing the set
button 808. Then, as shown in FIG. 14, a display 1401 displays an
image 1402 of the result of the first digital development
processing at "standard" setting values, and "gamma 1 (standard)"
on both a table 1403 and characteristic graph 1404.
[0131] The display sequentially changes to "gamma 2" and "gamma 3"
by pressing the cross key 812. As the gamma characteristic tables,
a table having a characteristic as shown in FIG. 6 is prepared. In
this case, the characteristic of "gamma 1" is a standard
characteristic 601, that of "gamma 2" is a characteristic which
provides a contrast higher than "gamma 1", and that of "gamma 3" is
a characteristic which provides a contrast lower than "gamma
1".
[0132] When a desired contrast is obtained, the photographer
presses the set button 808 to update the parameter setting value to
the current gamma characteristic table by the signal 237e. At this
time, digital development processing is performed again using this
parameter, and the image file 210 of the development result is sent
to and stored in the second memory 212, and displayed on the
display unit 211.
[0133] By repeating this operation, the photographer confirms an
image of a desired contrast on the image 1402 played back on the
display 1401, and then presses the recording instruction switch 805
in FIG. 8. In response to this, the recording instruction unit 213
outputs the recording instruction signal 214, and the image file
stored in the second memory 212 is sent to the recording unit 217
and recorded on the recording medium.
[0134] In this way, an image of a contrast desired by the
photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of the gamma characteristic table.
[0135] In the above description, development is executed again by
selecting a target one of gamma characteristic tables with the
cross keys 809 and 812 and changing the parameter. Alternatively,
images of redevelopment results may be sequentially displayed by
performing development again on the basis of a gamma characteristic
table changed every time either the cross key 809 or 812 is
pressed.
[0136] Of image processes, an image process of switching the
parameter setting value of the color gain correction unit 230 for
multiplying the chrominance components Cr and Cb by the gain will
be explained.
[0137] An image process of switching the parameter setting of color
gain correction is selected from image processes in digital
development processing by using the image process menu switch 813
and cross keys 809 to 812 in FIG. 8, and is determined by pressing
the set button 808. Then, as shown in FIG. 15, a display 1501
displays an image 1502 of the result of the first digital
development processing at "standard" setting values, and a gain
value 1503 of level correction. The result of the first digital
development processing is the result of photographing at a
"standard" color gain of x1.0, and thus "x1.0" is displayed as
shown in FIG. 15.
[0138] The display sequentially changes to "x1.2", "x1.4", . . . by
pressing the cross key 809, and "x0.8", "x0.6", . . . by pressing
the cross key 812. When a desired color gain value is displayed,
the photographer presses the set button 808 to update the parameter
setting value of the color gain correction unit 230 to the current
color gain value by the signal 237f. At this time, digital
development processing is performed again using this parameter, and
the image file 210 of the development result is sent to and stored
in the second memory 212, and displayed on the display unit
211.
[0139] By repeating this operation, the photographer confirms an
image of a desired color density on the image 1502 played back on
the display unit 211, and then presses the recording instruction
switch 805 in FIG. 8. In response to this, the recording
instruction unit 213 outputs the recording instruction signal 214,
and the image file stored in the second memory 212 is sent to the
recording unit 217 and recorded on the recording medium.
[0140] As a result, an image of an exposure desired by the
photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of color gain correction processing.
[0141] In the above description, development is executed again by
setting a target gain value of color gain correction with the cross
keys 809 and 812 and changing the parameter. Alternatively, images
of redevelopment results may be sequentially displayed by
performing development again at a gain value of color gain
correction that is changed every time either the cross key 809 or
812 is pressed.
[0142] Of image processes, an image process of switching the
parameter setting value of the hue adjustment unit 232 for rotating
the hues of the chrominance components Cr and Cb will be
explained.
[0143] An image process of switching the parameter setting of hue
adjustment is selected from image processes in digital development
processing by using the image process menu switch 813 and cross
keys 809 to 812 in FIG. 8, and is determined by pressing the set
button 808. Then, as shown in FIG. 16, a display 1601 displays an
image 1602 of the result of the first digital development
processing at "standard" setting values, and a hue adjustment table
1603. The result of the first digital development processing is the
result of photographing by "standard" hue adjustment, and thus
"standard" is displayed as shown in FIG. 16.
[0144] The display sequentially changes to "+1", "+2", . . . by
pressing the cross key 809, and "-1", "-2", . . . by pressing the
cross key 812. As each of the hue rotation tables, there is
prepared a hue rotation table having 2.times.2 element values so as
to change color reproduction in equation (B) described in the prior
art. The 2.times.2 matrix of equation (B) is a matrix which gives a
rotation angle .theta. on the CrCb color coordinate system, and the
same rotation angle is set at the step of each table.
[0145] When a desired hue table is displayed, the photographer
presses the set button 808 to update the parameter setting value of
the hue adjustment unit 232 to the current hue rotation matrix by
the signal 237g. At this time, digital development processing is
performed again using this parameter, and the image file 210 of the
development result is sent to and stored in the second memory 212,
and displayed on the display unit 211.
[0146] By repeating this operation, the photographer confirms an
image of a desired color reproduction on the image 1602 played back
on the display unit 211, and then presses the recording instruction
switch 805 in FIG. 8. In response to this, the recording
instruction unit 213 outputs the recording instruction signal 214,
and the image file stored in the second memory 212 is sent to the
recording unit 217 and recorded on the recording medium.
[0147] In this manner, an image of a color reproduction desired by
the photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of hue adjustment processing.
[0148] In the above description, development is executed again by
setting a target hue rotation table of hue adjustment with the
cross keys 809 and 812 and changing the parameter. Alternatively,
images of redevelopment results may be sequentially displayed by
performing development again on the basis of a hue rotation table
changed every time either the cross key 809 or 812 is pressed.
[0149] Of image processes, an image process of switching the
parameter setting value of the edge enhancement unit 233 will be
explained.
[0150] An image process of switching the parameter setting of edge
enhancement is selected from image processes in digital development
processing by using the image process menu switch 813 and cross
keys 809 to 812 in FIG. 8, and is determined by pressing the set
button 808. Then, as shown in FIG. 17, a display 1701 displays an
image 1702 of the result of the first digital development
processing at "standard" setting values, a partial enlarged image
1704 of the image, and an edge enhancement table 1703. The result
of the first digital development processing is the result of
photographing by "standard" edge enhancement, and thus "standard"
is displayed as shown in FIG. 17.
[0151] The display sequentially changes to "+1" and "+2" by
pressing the cross key 809, and "-1" and "-2" by pressing the cross
key 812. As each of the edge enhancement tables, a table which
changes the degree of edge enhancement is prepared, as described in
the prior art.
[0152] Similar to the prior art, a table capable of changing the
degree of edge enhancement is configured by preparing sets of the
numbers of adjacent pixels to be referred to for a pixel subjected
to edge enhancement, the gain values of edge enhancement, and
offset values serving as threshold levels used to detect an edge to
be enhanced. In any table, the number of adjacent pixels to be
referred to is set to eight.
[0153] For "standard", edge enhancement gain value: 1.0, offset
value: 4.0
[0154] For "+1", edge enhancement gain value: 2.0, offset value:
2.0
[0155] For "+2", edge enhancement gain value: 3.0, offset value:
1.0
[0156] For "-1", edge enhancement gain value: 0.5, offset value:
4.0
[0157] For "-2 (edge enhancement OFF)", edge enhancement gain
value: 0.0, offset value: arbitrary
[0158] When a desired edge enhancement table is displayed, the
photographer presses the set button 808 to update the parameter
setting value of the edge enhancement unit 233 to the current edge
enhancement table by the signal 237h. At this time, digital
development processing is performed again using this parameter, and
the image file 210 of the development result is sent to and stored
in the second memory 212, and displayed on the display unit
211.
[0159] By repeating this operation, the photographer confirms an
image of a desired sharpness on the images 1702 and 1704 played
back on the display unit 211, and then presses the recording
instruction switch 805 in FIG. 8. In response to this, the
recording instruction unit 213 outputs the recording instruction
signal 214, and the image file stored in the second memory 212 is
sent to the recording unit 217 and recorded on the recording
medium.
[0160] Accordingly, an image of a sharpness desired by the
photographer can be attained by recording an image which is
developed again after changing the "standard" setting value of the
parameter of edge enhancement processing.
[0161] In the above description, development is executed again by
setting a target table of edge enhancement with the cross keys 809
and 812 and changing the parameter. Alternatively, images of
redevelopment results may be sequentially displayed by performing
development again on the basis of an edge enhancement table changed
every time either the cross key 809 or 812 is pressed.
[0162] The numerical value can also be switched individually for
the number of adjacent pixels to be referred to in edge
enhancement, the edge enhancement gain value, and the offset
value.
[0163] With this operation, even if an image of an image quality
which does not reflect the intention of the photographer is
photographed due to a change in photographing conditions during
photographing, the development parameter can be switched and set
again to perform digital development processing. Whether the set
parameter is optimal can be easily confirmed, photographing need
not be repeated, and an optimal photographing result can always be
implemented without missing a photographing scene intended by the
photographer.
[0164] As described above, according to the first and second
embodiments, photographing data from the image sensor is
temporarily stored in the memory, and the image of the
photographing data as the result of digital development processing
is displayed. When the parameters of various image processes in
digital development processing are not proper for the photographed
image, the parameter settings are corrected again, and digital
development processing is done again by reading out photographing
data from the memory, implementing a photographed image of an image
quality intended by the photographer. A photographing scene
intended by the photographer is not missed, and an optimal
photographing result can always be implemented.
[0165] As has been described above, according to the embodiments, a
photographed image can undergo image processing which reflects the
intention of the user without performing photographing again.
OTHER EMBODIMENT
[0166] The object of the embodiments is also achieved when a
storage medium (or recording medium) which stores software program
codes for realizing the functions of the above-described
embodiments is supplied to a system or apparatus, and the computer
(or the CPU or MPU) of the system or apparatus reads out and
executes the program codes stored in the storage medium. In this
case, the program codes read out from the storage medium realize
the functions of the above-described embodiments, and the storage
medium which stores the program codes constitutes the present
invention. The functions of the above-described embodiments are
realized when the computer executes the readout program codes.
Also, the present invention includes a case in which an OS
(Operating System) or the like running on the computer performs
some or all of actual processes on the basis of the instructions of
the program codes and thereby realizes the functions of the
above-described embodiments.
[0167] Furthermore, the present invention includes a case in which,
after the program codes read out from the storage medium are
written in the memory of a function expansion card inserted into
the computer or the memory of a function expansion unit connected
to the computer, the CPU of the function expansion card or function
expansion unit performs some or all of actual processes on the
basis of the instructions of the program codes and thereby realizes
the functions of the above-described embodiments.
[0168] When the present invention is applied to the storage medium,
the storage medium stores program codes corresponding to the
above-described procedures.
[0169] The present invention is not limited to the above
embodiments and various changes and modifications can be made
within the spirit and scope of the present invention. Therefore, to
apprise the public of the scope of the present invention the
following claims are made.
CLAIM OF PRIORITY
[0170] This application claims priority from Japanese Patent
Application No. 2004-177345 filed on Jun. 15, 2004, the entire
contents of which are hereby incorporated by reference herein.
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