U.S. patent application number 11/756207 was filed with the patent office on 2007-12-13 for imaging apparatus, control method of imaging apparatus, and computer program.
This patent application is currently assigned to Sony Corporation. Invention is credited to Hisashi Ishiwata, Tetsuo Mise, Yoshito Terashima, Eiji Yamaoku.
Application Number | 20070285528 11/756207 |
Document ID | / |
Family ID | 38821507 |
Filed Date | 2007-12-13 |
United States Patent
Application |
20070285528 |
Kind Code |
A1 |
Mise; Tetsuo ; et
al. |
December 13, 2007 |
IMAGING APPARATUS, CONTROL METHOD OF IMAGING APPARATUS, AND
COMPUTER PROGRAM
Abstract
An imaging apparatus includes a face detecting unit detecting a
face region from an input image input to the imaging apparatus and
a control unit calculating a distance to a subject on the basis of
the face size detected by the face detection unit and displaying
distance identification information indicating a distance
corresponding to the calculated distance in a display unit.
Inventors: |
Mise; Tetsuo; (Tokyo,
JP) ; Terashima; Yoshito; (Tokyo, JP) ;
Ishiwata; Hisashi; (Kanagawa, JP) ; Yamaoku;
Eiji; (Tokyo, JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
Sony Corporation
Tokyo
JP
|
Family ID: |
38821507 |
Appl. No.: |
11/756207 |
Filed: |
May 31, 2007 |
Current U.S.
Class: |
348/222.1 ;
348/E5.045; 348/E5.047 |
Current CPC
Class: |
H04N 5/232933 20180801;
H04N 5/232945 20180801; H04N 5/232127 20180801; H04N 5/23218
20180801; H04N 5/23293 20130101; H04N 5/23219 20130101; H04N
5/23212 20130101 |
Class at
Publication: |
348/222.1 |
International
Class: |
H04N 5/228 20060101
H04N005/228 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 9, 2006 |
JP |
2006-160453 |
Claims
1. An imaging apparatus comprising: a face detecting unit detecting
a face region from an input image input to the imaging apparatus;
and a control unit calculating a distance to a subject on the basis
of the face size detected by the face detection unit and displaying
distance identification information indicating a distance
corresponding to the calculated distance in a display unit.
2. The imaging apparatus according to claim 1, wherein the control
unit displays a distance indicator in the display unit and performs
a display process of the distance identification information in a
position on the distance indicator corresponding to the distance
calculated on the basis of the face size.
3. The imaging apparatus according to claim 2, wherein the distance
identification information is a face icon.
4. The imaging apparatus according to claim 1, wherein the control
unit displays a distance indicator in the display unit and performs
a display process of the distance identification information in a
position on the distance indicator corresponding to the distance
calculated on the basis of the face size.
5. The imaging apparatus according to claim 1, wherein the control
unit performs control processes for displaying a face region
identification mark identifying a face in the image displayed in
the display unit and displaying the face region identification mark
and the distance identification information in accordance with a
setting that the display color of the face region identification
mark and the display color of the distance identification
information displayed in the position of the distance indicator are
correlated with each other for each face.
6. The imaging apparatus according to claim 1, wherein the control
unit performs control processes for displaying a face region
identification mark identifying a face in the image displayed in
the display unit and displaying a connection line connecting the
face region identification mark and the distance identification
information displayed in the position on the indicator to each
other.
7. The imaging apparatus according to claim 1, wherein the control
unit performs a control process for displaying the distance
identification information calculated on the basis of a face in
proximity of the face in the image displayed in the display
unit.
8. The imaging apparatus according to claim 1, wherein the control
unit displays a distance indicator in the display unit, displays
focal position information indicating a current focus point in the
distance indicator, and displays the distance identification
information in the position on the distance indicator corresponding
to the distance calculated on the basis of the face size, and
wherein the control unit determines whether the distance calculated
on the basis of the face size corresponds to a location in
proximity of the focal position and is in the range of the focal
positions and performs display indicating that the face is in the
focal position in a case where the distance is determined to be in
the focal position.
9. The imaging apparatus according to claim 1, wherein the control
unit blinks the distance identification information displayed in
the position on the indicator or changes the display color of the
distance identification information as the display indicating that
the face is in the focal position.
10. The imaging apparatus according to claim 1, wherein the control
unit performs control processes of displaying a face region
identification mark identifying a face in the image displayed in
the display unit and blinking the face region identification mark
or changing the display color of the face region identification
mark as the display indicating that the face corresponding to the
face region identification mark is in the focal position.
11. The imaging apparatus according to claim 1, wherein the control
unit sequentially calculates distances corresponding to each face
for a plurality of face regions detected by the face detecting unit
and performs a display process of the distance identification
information in positions in the distance indicator corresponding to
distances to each face along with the distance indicator to be
displayed in the display unit.
12. The imaging apparatus according to claim 1, wherein the control
unit sequentially calculates distances corresponding to each face
for a plurality of face regions detected by the face detecting unit
in accordance with defined priority levels and performs a display
process of the distance identification information in the positions
on the indicator corresponding to distances to each face along with
the distance indicator to be displayed in the display unit, and
wherein the control unit does not display the distance
identification information again in a case where the display of the
distance identification information in an expected display position
of the distance identification information has been already
completed.
13. The imaging apparatus according to claim 12, wherein the
defined priority levels are assigned such that a face region having
a larger face size detected by the face detection unit has a higher
priority level or that a face region corresponding to a face closer
to the center of the image to be analyzed has a higher priority
level.
14. A method of controlling an imaging apparatus which performs a
information display process, the method comprising the steps of:
detecting a face region from an input image input to the imaging
apparatus using a face detecting unit; and calculating a distance
to a subject on the basis of the face size detected by the face
detection unit and displaying distance identification information
indicating a distance corresponding to the calculated distance in a
display unit using a control unit.
15. The method according to claim 14, wherein the calculation of
the distance and display of the identification information includes
displaying a distance indicator in the display unit and performing
a display process of the distance identification information in a
position on the distance indicator corresponding to the distance
calculated on the basis of the face size.
16. The method according to claim 15, wherein the distance
identification information is a face icon.
17. The method according to claim 14, wherein the calculation of
the distance and display of the identification information includes
displaying a distance indicator in the display unit and performing
a display process of the distance identification information in the
position on the distance indicator corresponding to the distance
calculated on the basis of the face size.
18. The method according to claim 14, wherein the calculation of
the distance and display of the identification information further
includes performing control processes for displaying a face region
identification mark identifying a face in the image displayed in
the display unit and displaying the face region identification mark
and the distance identification information in accordance with a
setting that the display color of the face region identification
mark and the display color of the distance identification
information displayed in the position of the distance indicator are
correlated with each other for each face.
19. The method according to claim 14, wherein the calculation of
the distance and display of the identification information further
includes performing control processes for displaying a face region
identification mark identifying a face in the image displayed in
the display unit and displaying a connection line connecting the
face region identification mark and the distance identification
information displayed in the position of the indicator to each
other.
20. The method according to claim 14, wherein the calculation of
the distance and display of the identification information further
includes performing a control process for displaying the distance
identification information calculated on the basis of a face in
proximity of the face in the image displayed in the display
unit.
21. The method according to claim 14, wherein the calculation of
the distance and display of the identification information includes
displaying a distance indicator in the display unit, displaying
focal position information indicating a current focus point in the
distance indicator, and displaying the distance identification
information in the position on the distance indicator corresponding
to the distance calculated on the basis of the face size, and
wherein the control unit determines whether the distance calculated
on the basis of the face size corresponds to a location in
proximity of the focal position and is in the range of the focal
positions and performs display indicating that the face is in the
focal position in a case where the distance is determined to be in
the focal position.
22. The method according to claim 14, wherein the determining and
performing of displaying indicating that the face is in the focal
position includes blinking the distance identification information
displayed in the position on the indicator or changing the display
color of the distance identification information as the display
indicating that the face is in the focal position.
23. The method according to claim 14, wherein the control unit
displays a face region identification mark identifying a face in
the image displayed in the display unit and blinks the face region
identification mark or changes the display color of the face region
identification mark as the display indicating that the face
corresponding to the face region identification mark is in the
focal position.
24. The method according to claim 14, further comprising
sequentially calculating distances corresponding to each face for a
plurality of face regions detected by the face detecting unit and
performing a display process of the distance identification
information in positions in the distance indicator corresponding to
distances to each face along with the distance indicator to be
displayed in the display unit, by using the control unit.
25. The method according to claim 14, further comprising
sequentially calculating distances corresponding to each face for a
plurality of face regions detected by the face detecting unit in
accordance with defined priority levels, performing a display
process of the distance identification information in the positions
on the indicator corresponding to distances to each face along with
the distance indicator to be displayed in the display unit by using
the control unit, and not displaying the distance identification
information again in a case where the display of the distance
identification information in an expected display position of the
distance identification information has been already completed, by
using the control unit.
26. The method according to claim 25, wherein the defined priority
levels are assigned such that a face region having a larger face
size detected by the face detection unit has a higher priority
level or that a face region corresponding to a face closer to the
center of the image to be analyzed has a higher priority level.
27. A computer program which allows a computer to perform an
information display process control in an imaging apparatus, the
computer program allowing a computer to perform the steps of:
detecting a face region from an input image input to the imaging
apparatus using a face detecting unit; and calculating a distance
to a subject on the basis of the face size detected by the face
detection unit and displaying distance identification information
indicating a distance corresponding to the calculated distance in a
display unit using a control unit.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present invention contains subject matter related to
Japanese Patent Application JP 2006-160453 filed in the Japanese
Patent Office on Jun. 9, 2006, the entire contents of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to an imaging apparatus, a
control method of imaging apparatuses, and a computer program, and
more particularly, to an imaging apparatus, a control method of
imaging apparatuses, and a computer program which are capable of
calculating a distance to a subject on the basis of a face of a
person as a subject and providing a user with the calculated
distance information.
[0004] 2. Background Art
[0005] Focusing processing for bringing an imaging apparatus such
as a digital still camera and a digital video camera into focus on
a subject includes auto-focus processing in which focus adjustment
is performed automatically and manual-focus processing in which
focus adjustment is performed by the user operation. Generally,
when the focus adjustment is performed by manual-focus operation,
adjustment is performed while viewing an image on a monitor such as
a liquid crystal display (LCD) and an electronic view finder
(EVF).
[0006] As reference information for a case where the focus
adjustment is performed by a manual operation with an image in the
monitor being watched, a configuration in which an indicator
indicating a focal distance on the basis of a position of a focus
lens is displayed in a monitor screen is, for example, disclosed in
JP-A-2004-94103. In addition, a configuration in which an indicator
indicating the degree of in-focus for a subject is displayed is
disclosed in JP-A-2002-209135 and JP-A-2005-181373.
[0007] However, generally, the LCD or EVF as a monitor which is
built in the imaging apparatus has a relatively low resolution, and
it is difficult to precisely determine whether a target subject is
in focus from an image in the monitor. As a technique for solving
this problem, an imaging apparatus which has a function of
displaying an image in the monitor on an enlarged scale has been
provided.
[0008] However, when the display on an enlarged scale is performed,
there is a problem that detection of an actual distance to a
subject from the display on the screen becomes difficult. As a
result, a user performs a manual focus operation randomly until a
person is in focus, and only after the person is in focus, the user
can acquire an approximate distance to the person. In other words,
in this case, the indicator rarely performs a function of
supporting the manual focus control of the user.
SUMMARY OF THE INVENTION
[0009] Under the circumstances, it is desirable to perform a fast
and precise focus process for a target subject. More particularly,
it is desirable to provide an imaging apparatus, a control method
of imaging apparatuses, and a computer program which implement
effective user supports in the manual focus process by performing a
distance detection on the basis of a face of a person and
displaying the detected distance information correlated with a
distance indicator.
[0010] According to an embodiment of the present invention, there
is provided an imaging apparatus including a face detecting unit
detecting a face region from an input image input to the imaging
apparatus, and a control unit calculating a distance to a subject
on the basis of the face size detected by the face detection unit
and displaying distance identification information indicating a
distance corresponding to the calculated distance in a display
unit.
[0011] In the imaging apparatus, the control unit may display a
distance indicator in the display unit and perform a display
process of the distance identification information in a position on
the distance indicator corresponding to the distance calculated on
the basis of the face size.
[0012] In the imaging apparatus, the distance identification
information may be a face icon.
[0013] In the imaging apparatus, the control unit may display a
distance indicator in the display unit and perform a display
process of the distance identification information in a position on
the distance indicator corresponding to the distance calculated on
the basis of the face size.
[0014] In the imaging apparatus, the control unit may perform
control processes for displaying a face region identification mark
identifying a face in the image displayed in the display unit and
displaying the face region identification mark and the distance
identification information in accordance with a setting that the
display color of the face region identification mark and the
display color of the distance identification information displayed
in the position of the distance indicator are correlated with each
other for each face.
[0015] In the imaging apparatus, the control unit may perform
control processes for displaying a face region identification mark
identifying a face in the image displayed in the display unit and
displaying a connection line connecting the face region
identification mark and the distance identification information
displayed in the position on the indicator to each other.
[0016] In the imaging apparatus, the control unit may perform a
control process for displaying the distance identification
information calculated on the basis of a face in proximity of the
face in the image displayed in the display unit.
[0017] In the imaging apparatus, the control unit may display a
distance indicator in the display unit, display focal position
information indicating a current focus point in the distance
indicator, and display the distance identification information in
the position on the distance indicator corresponding to the
distance calculated on the basis of the face size, and the control
unit may determine whether the distance calculated on the basis of
the face size corresponds to a location in proximity of the focal
position and is in the range of the focal positions and perform
display indicating that the face is in the focal position in a case
where the distance is determined to be in the focal position.
[0018] In the imaging apparatus, the control unit may blink the
distance identification information displayed in the position on
the indicator or change the display color of the distance
identification information as the display indicating that the face
is in the focal position.
[0019] In the imaging apparatus, the control unit may perform
control processes of displaying a face region identification mark
identifying a face in the image displayed in the display unit and
blinking the face region identification mark or changing the
display color of the face region identification mark as the display
indicating that the face corresponding to the face region
identification mark is in the focal position.
[0020] In the imaging apparatus, the control unit may sequentially
calculate distances corresponding to each face for a plurality of
face regions detected by the face detecting unit and performs a
display process of the distance identification information in
positions in the distance indicator corresponding to distances to
each face along with the distance indicator to be displayed in the
display unit.
[0021] In the imaging apparatus, the control unit may sequentially
calculate distances corresponding to each face for a plurality of
face regions detected by the face detecting unit in accordance with
defined priority levels and perform a display process of the
distance identification information in the positions on the
indicator corresponding to distances to each face along with the
distance indicator to be displayed in the display unit, and the
control unit may not display the distance identification
information again in a case where the display of the distance
identification information in an expected display position of the
distance identification information has been already completed.
[0022] In the imaging apparatus, the defined priority levels may be
assigned such that a face region having a larger face size detected
by the face detection unit has a higher priority level or that a
face region corresponding to a face closer to the center of the
image to be analyzed has a higher priority level.
[0023] According to another embodiment of the present invention,
there is provided a method of controlling an imaging apparatus
which performs a information display process, the method including
the steps of detecting a face region from an input image input to
the imaging apparatus using a face detecting unit, and calculating
a distance to a subject on the basis of the face size detected by
the face detection unit and displaying distance identification
information indicating a distance corresponding to the calculated
distance in a display unit using a control unit.
[0024] In the method, the calculation of the distance and display
of the identification information may include displaying a distance
indicator in the display unit and performing a display process of
the distance identification information in a position on the
distance indicator corresponding to the distance calculated on the
basis of the face size.
[0025] In the method, the distance identification information may
be a face icon.
[0026] In the method, the calculation of the distance and display
of the identification information may include displaying a distance
indicator in the display unit and performing a display process of
the distance identification information in the position on the
distance indicator corresponding to the distance calculated on the
basis of the face size.
[0027] In the method, the calculation of the distance and display
of the identification information may further include performing
control processes for displaying a face region identification mark
identifying a face in the image displayed in the display unit and
displaying the face region identification mark and the distance
identification information in accordance with a setting that the
display color of the face region identification mark and the
display color of the distance identification information displayed
in the position of the distance indicator are correlated with each
other for each face.
[0028] In the method, the calculation of the distance and display
of the identification information may further include performing
control processes for displaying a face region identification mark
identifying a face in the image displayed in the display unit and
displaying a connection line connecting the face region
identification mark and the distance identification information
displayed in the position of the indicator to each other.
[0029] In the method, the calculation of the distance and display
of the identification information may further include performing a
control process for displaying the distance identification
information calculated on the basis of a face in proximity of the
face in the image displayed in the display unit.
[0030] In the method, the calculation of the distance and display
of the identification information may include displaying a distance
indicator in the display unit, displaying focal position
information indicating a current focus point in the distance
indicator, and displaying the distance identification information
in the position on the distance indicator corresponding to the
distance calculated on the basis of the face size, and the control
unit may determine whether the distance calculated on the basis of
the face size corresponds to a location in proximity of the focal
position and is in the range of the focal positions and perform
display indicating that the face is in the focal position in a case
where the distance is determined to be in the focal position.
[0031] In the method, the determining and performing of displaying
indicating that the face is in the focal position may include
blinking the distance identification information displayed in the
position on the indicator or changing the display color of the
distance identification information as the display indicating that
the face is in the focal position.
[0032] In the method, the control unit may display a face region
identification mark identifying a face in the image displayed in
the display unit and may blink the face region identification mark
or change the display color of the face region identification mark
as the display indicating that the face corresponding to the face
region identification mark is in the focal position.
[0033] The method may further include sequentially calculating
distances corresponding to each face for a plurality of face
regions detected by the face detecting unit and performing a
display process of the distance identification information in
positions in the distance indicator corresponding to distances to
each face along with the distance indicator to be displayed in the
display unit, by using the control unit.
[0034] The method may further include sequentially calculating
distances corresponding to each face for a plurality of face
regions detected by the face detecting unit in accordance with
defined priority levels, performing a display process of the
distance identification information in the positions on the
indicator corresponding to distances to each face along with the
distance indicator to be displayed in the display unit by using the
control unit, and not displaying the distance identification
information again in a case where the display of the distance
identification information in an expected display position of the
distance identification information has been already completed, by
using the control unit.
[0035] In the method, the defined priority levels may be assigned
such that a face region having a larger face size detected by the
face detection unit has a higher priority level or that a face
region corresponding to a face closer to the center of the image to
be analyzed has a higher priority level.
[0036] According to another embodiment of the present invention,
there is provided a computer program which allows a computer to
perform an information display process control in an imaging
apparatus, the computer program allowing a computer to perform the
steps of detecting a face region from an input image input to the
imaging apparatus using a face detecting unit, and calculating a
distance to a subject on the basis of the face size detected by the
face detection unit and displaying distance identification
information indicating a distance corresponding to the calculated
distance in a display unit using a control unit.
[0037] The computer program according to the another embodiment of
the present invention, for example, may be provided on a storage
medium, or a communication medium which are provided in a
computer-readable format, for example, a storage medium such as CD,
FD, or MO or a communication medium such as a network, for
general-purpose computer systems that can execute various program
codes. By providing the computer program in a computer-readable
format, a process on the basis of the computer program is performed
in a computer system.
[0038] Other objects, features, or advantages of the present
invention will be disclosed in the detailed description on the
basis of exemplary embodiments or accompanying drawings. A "system"
in the following description is a configuration of a logical
combination of a plurality of devices and is not limited to a case
where each constituent device is in one body.
[0039] According to an embodiment of the present invention, a face
detecting process and a distance calculating process are performed
in an imaging apparatus, and a distance identification information
such as a face icon is displayed in a position corresponding to the
calculated distance in the distance indicator which is displayed on
a monitor screen or a viewfinder. The user can intuitively
recognize a distance to the person from the display of the distance
identification information and also can easily recognize an
approximate distance to the person from the face icon displayed in
the distance indicator in a focus adjustment process by a manual
focus operation, whereby the manual focus control (focus
adjustment) can be performed efficiently and precisely.
[0040] According to another embodiment of the invention, a set
color for a face region identification mark which is configured to
surround a subject image displayed in a monitor or a view finder
and the color of the distance identification information such as a
face icon correspondently displayed in the distance indicator are
configured to be identical to each other or a connection line is
connected for displaying, and thus it is easy to recognize a
distance to a target subject even in a case where a plurality of
faces are displayed in the monitor, whereby it becomes possible to
precisely perform a focus adjustment operation on the target
subject.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIGS. 1A to 1C are diagrams showing an external appearance
of an imaging apparatus according to an embodiment of the present
invention.
[0042] FIG. 2 is a diagram showing a hardware configuration of an
imaging apparatus according to an embodiment of the present
invention.
[0043] FIG. 3 is a diagram showing an example of data display in an
imaging apparatus according to an embodiment of the present
invention.
[0044] FIGS. 4A and 4B are diagrams showing examples of distance
indicators according to an embodiment of the present invention.
[0045] FIG. 5 is a diagram showing a subject distance calculating
process on the basis of a face size according to an embodiment of
the present invention.
[0046] FIG. 6 is a diagram showing a configuration and process of a
face size reference value calculating unit according to an
embodiment of the present invention.
[0047] FIGS. 7A and 7B are diagrams showing examples of reference
value calculating tables which are used in a face size reference
value calculating unit according to an embodiment of the present
invention.
[0048] FIG. 8C is a diagram showing an example of a reference value
calculating table which is used in a face size reference value
calculating unit according to an embodiment of the present
invention.
[0049] FIG. 9D is a diagram showing an example of a reference value
calculating table which is used in a face size reference value
calculating unit according to an embodiment of the present
invention.
[0050] FIG. 10 is a flowchart showing the sequence of face
detection, distance calculation, and display control on the basis
of the calculated distance information of an imaging apparatus
according to an embodiment of the present invention.
[0051] FIG. 11 is a diagram showing a condition for a process of
blinking a face icon.
[0052] FIG. 12 is flowchart showing the sequence of face detection,
distance calculation, and display control on the basis of the
calculated distance information in a case where a plurality of
faces are detected according to an embodiment of the present
invention.
[0053] FIG. 13 is a diagram showing an example of data display in
an imaging apparatus according to an embodiment of the present
invention.
[0054] FIG. 14 is a diagram showing an example of data display in
an imaging apparatus according to an embodiment of the present
invention.
[0055] FIG. 15 is a diagram showing an example of data display in
an imaging apparatus according to an embodiment of the present
invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0056] Hereinafter, an imaging apparatus, a control method of
imaging apparatuses, and a computer program according to
embodiments of the present invention will be described in detail
with reference to accompanying drawings. An imaging apparatus
according to an embodiment of the invention detects a face of a
person which is a subject, calculates a distance to the detected
face, and displays information on the calculated distance in a
display unit of the imaging apparatus, that is, a monitor screen or
a viewfinder and an indicator, therefore user support in a manual
focus process is implemented. In other words, information enabling
a user (photographer) to intuitively recognize a distance to a
person as a subject is provided, whereby the manual focus operation
can be performed efficiently and precisely.
[0057] To be more specifically, when a photographer photographs a
person by performing a manual focus operation, a face detecting
process and a distance calculating process are performed, and
distance identification information such as a face icon is
displayed on a distance indicator which is displayed on a monitor
screen or a viewfinder or in a position adjacent to the indicator
corresponding to the calculated distance. The photographer can
intuitively recognize the distance to the person from the display.
Since the photographer can easily recognize an approximate distance
to the person by the face icon additionally displayed on the
indicator before performing focus adjustment through a manual focus
operation, the photographer can perform the manual focus control
(focus adjustment) effectively and precisely.
[0058] In addition, the color of a focus adjustment frame which is
configured to surround a subject, for which the focus adjustment
has been completed, to be displayed and the color of the distance
identification information such as a face icon correspondently
displayed on the indicator are configured to be the same, and thus,
the distance to the target subject can be easily recognized even in
a case where a plurality of faces are displayed on the monitor,
whereby it becomes possible to precisely perform a focus adjustment
process for the target subject.
[0059] The face icon on the focus indicator is configured to change
its display position in accordance with the forward/backward
movement (the distance to the subject is moved forward/backward) of
a person, and when the person moves, display in accordance with the
movement is performed, whereby the user can recognize the movement
of the subject from the monitor screen.
[0060] At first, the configuration of an imaging apparatus
according to an embodiment of the present invention will be
described. FIGS. 1A to 1C are diagrams showing an external
appearance of an imaging apparatus 10 according to an embodiment of
the invention. FIG. 1A is a top view, FIG. 1B is a front elevation,
and FIG. 1C is a bottom view of the imaging apparatus 10. A lens
part in FIG. 1A is represented as sectional view. The imaging
apparatus 10 includes a power switch 11, trigger means, that is, a
release switch 12 serving as a shutter, a monitor 13 for displaying
an image (through image) photographed by the imaging apparatus or
operation information, an imager 14 as an imaging device (CCD), a
zoom button 15 for performing zoom control, an operation button 16
for inputting various operation information such as a manual focus
process, a viewfinder 17 for checking image (through image)
photographed by the imaging apparatus, a focus lens 18 driven in a
focus adjustment operation, a zoom lens 19 driven in a zoom
adjustment operation, a mode dial 20 for setting a photograph mode,
a focus lens motor (M1) 21 for driving the focus lens 18, and a
zoom lens motor (M2) 22 for driving the zoom lens 19.
[0061] The image of the subject is displayed in the viewfinder 17
and on the monitor 13 which are display units. The viewfinder 17
and the monitor 13, for example, are configured by an LCD,
respectively, and an image of the subject passing through the lens
is displayed as a motion picture. The motion picture is called a
through image. A user checks the viewfinder 17 or the monitor 13
for checking a target subject for photographing and pushes the
release switch 12 as a shutter, whereby the recording process of
the image is to be performed.
[0062] The internal configuration of an imaging apparatus 100
according to an embodiment of the invention will be described with
reference to FIG. 2. The incident light passing through a focus
lens 101 and a zoom lens 102, for example, is input to an imaging
device 103 such as a CCD (Charge Coupled Device) and is
photoelectric-converted in the imaging device 103. The
photoelectric-converted data is input to an analog signal processor
104, a process such as noise removing process is performed on the
data by the analog signal processor 104, and the data is converted
into a digital signal in an A/D converter 105. Various signal
processing and correction processes are performed in a digital
signal processor 108 on the data that has been converted into a
digital signal in the A/D 105, and the data processed by the
digital signal processor 108 is recorded in a recording device 115,
for example, including a flash memory. In addition, the processed
data is displayed in a monitor 117 and a viewfinder (EVF) 116. In
the monitor 117 and the viewfinder (EVF) 116, an image passing
through the lenses is displayed as a through image regardless of
performing image pickup.
[0063] An operation unit 118 includes the release switch 12, the
zoom button 15, the operation button 16 for inputting various
operation information such as manual focus process operation
information, and the mode dial 20 for setting a photograph mode
which are disposed in a camera main body described with reference
to FIGS. 1A to 1C.
[0064] A control unit 110 includes a CPU and performs control
operations for various processes performed by the imaging apparatus
on the basis of program stored in a memory (ROM) 120 or the like in
advance. A memory (EEPROM) 119 is non-volatile, and image data,
various auxiliary information, programs, and the like are stored
therein. The memory (ROM) 120 stores a program, an operation
parameter, or the like which is used by the control unit (CPU) 110.
A memory (RAM) 121 stores a program used by the control unit (CPU)
110, a parameter that changes appropriately in the operation of the
control unit, or the like. A gyro 111 detects the inclination,
shaking, or the like of the imaging apparatus. The detected
information is input to the control unit (CPU) 110, and a process
such as a process for preventing hand blur is performed.
[0065] A motor driver 112 drives a focus lens driving motor 113 set
in accordance with the focus lens 101 and a zoom lens driving motor
114 set in accordance with the zoom lens 102. A vertical driver 107
drives the imaging device (CCD) 103. A timing generator 106
generates a control signal for process timings of the imaging
device 103 and the analog signal processor 104 and controls the
process timings thereof.
[0066] A face detecting unit 130 detects a face region of a person
in image data by analyzing the image data input through a lens. The
detected information is sent to the control unit 110, and the
control unit 110 determines a face region of a person as a target
subject and measures a distance to the subject on the basis of the
determined face region.
[0067] The imaging apparatus according to an embodiment of the
present invention can perform a manual focus adjustment, that is, a
manual focus process as a focus process. When a photographer
photographs a person by a manual focus operation, the face
detection unit 130 performs a face detecting process, the control
unit 110 performs a distance calculating process on the basic of
the detected face information and displays distance identification
information such as a face icon in a position corresponding to the
calculated distance on a distance indicator which is displayed in
the monitor 117 or the viewfinder 116. The photographer can
intuitively recognize a distance to the person from the display of
the distance identification information.
[0068] A detailed example of the display is shown in FIG. 3. As
shown in FIG. 3, display information 200 shown in the figure is
displayed on the monitor 13 of the imaging apparatus 10. Here,
although only the monitor 13 is shown, a same image is displayed in
the viewfinder. In the display information 200, a distance
indicator 210 is displayed together with an image (through image)
that is currently in a photographing process. The distance
indicator 210 in the example, shown in the figure, indicates a
close distance in the left end and an infinite distance in the
right end. Focal position information 211 corresponding to a focus
setting distance position which corresponds to the current position
of the focus lens is appeared on the distance indicator. The focal
position information 211 slides on the distance indicator in
accordance with the movement of the focus lens on the basis of a
user's manual focus adjustment.
[0069] In the imaging apparatus according to an embodiment of the
invention, a face icon as shown in the figure is displayed in a
position on the indicator corresponding to the calculated distance
on the basis of the calculated distance information which is
acquired by the face region detection by the face detecting unit
130 and the calculation of the distance to the face by the control
unit 110. In the example shown in the figure, a face icon 221
appears in a position on the indicator corresponding to the
calculated distance (about 1 m) for a face 201 included in the
displayed image as a through image, and a face icon 222 in the
displayed image appears in a position on the indicator
corresponding to the calculated distance (about 2.2 m) for a face
202. These face icons are displayed in colors different from each
other respectively corresponding to the faces 201 and 202. These
colors are respectively correlated with the set colors of face
region identification marks 203 and 204 appearing on the monitor
image corresponding to the faces to which distances are calculated.
The face region identification marks 203 and 204 are also used as
focus frames, that is, information for indicating the success of
focus adjustment for the subjects, and when the focus adjustment is
succeeded, the face region identification marks 203 and 204 are
displayed blinking. In addition, when the focus adjustment is
succeeded, the face icons 221 and 222 are also displayed
blinking.
[0070] In the example shown in the figure, a red face region
identification mark 203 is displayed for the face 201, and a blue
face region identification mark 204 is displayed for the face 202.
The colors of the face icons indicating distance information are
displayed such that the face icon 221 corresponding to the distance
calculated for the face 201 is displayed in red and the face icon
222 corresponding to the distance calculated for the face 202 is
displayed in blue. With the display color, the user can know which
subject is what distance in a moment.
[0071] As described above, the face region identification marks 203
and 204 are used as focus frames, additionally. When a subject is
in focus (focus adjustment success) by the focus adjusting process
of the imaging apparatus, an in-focus display is performed so as to
make the subject in the monitor image for which the focus
adjustment is completed identifiable. The in-focus display is
identification information displayed for indicating the completion
of the focus adjustment in the image displayed in the monitor or
the viewfinder, and, for example, a frame surrounding a face is
displayed as the in-focus frame, generally. The user checks this
in-focus display and presses the shutter for photographing, whereby
a precise photographing can be made.
[0072] In the configuration according to the embodiment of the
invention, a face region identification mark is displayed blinking
to indicate the success of focus adjustment. For example, in the
example shown in the figure, the focus adjustment for the face 201
is succeeded, and in this case, the face region identification mark
203 is displayed to be blinking. At this time, the face icon 221
corresponding to the calculated distance for the face 201 is
displayed to be blinking. The user checks the success of focus
adjustment on the basis of the blinking display and presses the
shutter for photographing, whereby photographing an image with
precise focus adjustment can be performed.
[0073] The display of the distance indicator 210 is converted on
the basis of the distance to the subject. In other words, as shown
in FIGS. 4A and 4B, the display mode is shifted among a plurality
of distance indicators having different distance ranges. FIG. 4A
shows a distance indicator having the distance range of 2 to 90 cm,
and FIG. 4B shows a distance indicator having the distance range of
90 to infinity. As described above, one of the plurality of
distance indicators are selected to be displayed. For example, when
all the distances calculated on the basis of faces, which are
detected by the face detecting unit 130, by the control unit 110
are within 90 cm, the control unit 110 displays the distance
indicator shown in FIG. 4A and performs a process of displaying a
face icon on the distance indicator or in proximity thereof. On the
other hand, when there is a face to which the calculated distance
is greater than 90 cm, the control unit 110 displays the distance
indicator shown in FIG. 4B and performs a process of displaying a
face icon on the distance indicator or in proximity thereof.
[0074] When an imaging apparatus according to an embodiment of the
invention is used, a photographer can easily recognize an
approximate distance to a person by the display on the distance
indicator 210 as shown in FIG. 3, before performing focus
adjustment through a manual focus operation, and accordingly, the
photographer can perform the manual focus control (focus
adjustment) effectively and precisely. The face icon on the focus
indicator is configured to change its display position in
accordance with the forward/backward movement (the distance to the
subject is moved forward/backward) of a person, and when the person
moves, display in accordance with the movement is performed,
whereby the user can recognize the movement of the subject from the
monitor screen.
[0075] In the imaging apparatus according to an embodiment of the
invention, a face region of a person in the target subject is
determined on the basis of the image data photographed by the
imaging apparatus and a distance calculating process is performed
on the basis of the face image. In other words, a face region
detecting process using the face detection unit 130 and a
calculation process of the distance to the face using the control
unit 110 are performed. Hereinafter, the detailed configuration for
the processes will be described. The description is performed in
the order of the following contents.
[0076] (1) Face Identification Process
[0077] (2) Subject Distance Calculating Process on the Basis of
Face Size
(1) Face Identification Process
[0078] At first, the process performed by the face detecting unit
130, that is, a technique for determining a face region of a person
from image data acquired by the imaging apparatus will be
described. As a technique for recognizing and tracking a face,
various techniques in related art have been disclosed, and the
techniques can be applied. For example, by matching a template in
which information on the luminance distribution of the face is
recorded with an actual image, the determination of the face region
of the person can be implemented as shown in JP-A-2004-133637. At
first, a plurality of images to which a size-reduction process has
been performed are prepared. A group of templates of luminance
distribution information of the face which can be acquired in a
case where the face is tilted in the plurality of images is
prepared, and the templates are matched one by one. The templates
are acquired by tilting the face with respect to each X, Y, and Z
axes of a three-dimensional orthogonal coordinate system, and by
performing a match with the templates, the tilt of the actual face
is determined.
[0079] If a region of the size-reduced image matches with a
template when the size-reduced image is moved gradually in a
two-dimensional plane, then the region becomes a region in which a
face exists, and the size of the face can be acquired from the
reduction ratio of the actual image. In addition, the rotation
angles around the orthogonal three axes, a yaw angle, a pitch
angle, and a roll angle can be obtained from the template used at
that time. The calculation of the distance to the face is performed
by using the resultant size, position, and rotation angles of the
face.
[0080] As described above with reference to FIG. 3, on the basis of
the distance information calculated from the face image, the
distance identification display such as a face icon is performed in
a position corresponding to the calculated distance position on the
indicator which is displayed in a display unit such as the monitor
117 and the viewfinder (EVF) 116.
(2) Subject Distance Calculating Process on the Basis of Face
Size
[0081] Hereinafter, a detailed calculation method of the distance
to the face will be described. In the imaging apparatus according
to an embodiment of the invention, the distance to the face is
acquired on the basis of the size of a face included in an image
photographed by the imaging apparatus. This process will now be
described with reference to FIG. 5. In FIG. 5, the position of a
subject 301, a focus lens 302, and an imaging apparatus 303 are
represented. In the position of the subject 301, a face of a person
exists. The face size (width of the face) is Wf.
[0082] When the actual face size Wf is known, the distance Df to
the face, that is, the distance Df to the subject which is a
distance from the focus lens 302 to the position of the subject 301
can be acquired using the following equation on the basis of a
basic physical theory for lenses.
Df=Wref.times.(f/Wi).times.(Ww/Wf) (Equation 1.1)
[0083] The description for the symbols in the equation above is
followed below.
[0084] Wref: face size reference value of a person
[0085] Wi: width of the imaging apparatus
[0086] f: focal distance
[0087] Wf: number of pixels (value detected by the imaging
apparatus) of the face size of a person in the imaging
apparatus
[0088] Ww: number of pixels (value detected by the imaging
apparatus) of the size of an image used for detection of the face
of a person
[0089] As the face size reference value Wref of a person, a
predetermined fixed value may be used. A process of setting the
face size reference value Wref of a person to a value set in
consideration with an individual difference, an ethnic group
difference, an age difference, a sex difference, and the like may
be performed, and more precise distance estimation can be made by
the process. The configuration for the process will be described in
a latter part.
[0090] The imaging apparatus calculates the distance Df to the
subject by using above-described Equation 1.1 on the basis of the
image (through image) photographed by the imaging apparatus and
displays an identifier such as a face icon in a position
corresponding to the calculated distance on the distance indicator
displayed in the display unit as described with reference to FIG. 3
on the basis of the calculated the distance Df to the subject. As
described above, when a plurality of faces are included in the
image, the distances corresponding to each face are calculated.
Icons in different colors corresponding to each face and face
region identification marks for each face are displayed.
[0091] The face size reference value Wref of a person which is used
in the distance calculating Equation 1.1 may be a predetermined
fixed value, but a process of setting the face size reference value
Wref of a person to a value set in consideration of an individual
difference, an ethnic group difference, an age difference, a sex
difference, and the like may be performed. The configuration of the
process will now be described with reference to FIG. 6 and other
figures thereafter. The process is configured such that the face
size reference value Wref of a person is set to an appropriate
value in accordance with the ethnic group, sex, age, and physique
corresponding to the subject for calculating a precise distance Df
to the subject. For this process, the face size reference value
Wref of a person corresponding to various ethnic groups, sexes,
ages, and physiques is calculated for being used. For example,
table data for calculating the face size reference value Wref of a
person corresponding to various ethnic groups, sexes, ages, and
physiques is maintained, the information on the ethnic group, sex,
age, and physique corresponding to the subject is acquired on the
basis of the analysis result of an image or information input from
the user and the face size reference value Wref in accordance with
the subject is acquired from a table on the basis of the acquired
information.
[0092] It is possible to estimate the ethnic group, sex, age, and
physique of a person having a face by the analysis of the image of
the face included in the image photographed by the imaging
apparatus. In other words, parts of the face are identified, and
the parts are matched with part information registered in advance
corresponding to each ethnic group, sex, age, and physique, whereby
the ethnic group, sex, age, and physique of the subject are
estimated. Alternatively, a user such as a photographer inputs
subject information on the ethnic group, sex, age, and physique as
subject information, and the input information may be applied.
[0093] As described above, the information on the ethnic group,
sex, age, and physique of the subject is acquired from the image
analysis process or the user's input information, whereby an
appropriate face size reference value Wref in accordance with the
subject is acquired. An example of this process will be described
with reference to FIG. 6.
[0094] As shown in FIG. 6, the imaging apparatus includes a face
size reference value Wref calculating unit 310. The face size
reference value Wref calculating unit 310 includes a reference
value calculating table 311 for each race, a reference value
calculating table 312 for each sex, a reference value calculating
table 313 for each age, a reference value calculating table 314 for
each physique, and a data processing section 320.
[0095] An image analyzing unit 331 can estimate the ethnic group,
sex, age, and physique of a person having a face by the analysis of
the image of the face included in the image photographed by the
imaging apparatus. In other words, parts of the face are
identified, and the parts are matched with part information
registered in advance corresponding to each ethnic group, sex, age,
and physique, whereby the ethnic group, sex, age, and physique of
the subject are estimated. Then, the estimated information is input
to the face size reference value Wref calculating unit 310.
Alternatively, a user such as a photographer may input subject
information on the ethnic group, sex, age, and physique as subject
information through a user input unit 332, and the input
information may be input to the face size reference value Wref
calculating unit 310.
[0096] The face size reference value Wref calculating unit 310
calculates an optimal reference value Wref by applying the tables
on the basis of the subject information which is input from the
image analyzing unit 331 or the user input unit 332. A reference
value range Wref=(Wref+.DELTA.Wrefb) to (Wref-.DELTA.Wrerfs) in
consideration with non-uniformity of actual outputs to some degree
may be calculated. In this case, resultant values in consideration
with an assumed upper discrepancy of .DELTA.Wrefb and an assumed
lower discrepancy of .DELTA.Wrefs are output.
[0097] Examples of the tables will now be described with reference
to FIGS. 7A to 9D. FIG. 7A is a reference value calculating table
for each race, FIG. 7B is a reference value calculating table for
each race and sex, FIG. 8C is a reference value calculating table
for each race, sex, and age, and FIG. 9D is a reference value
calculating table for each race, sex, age, and physique. In the
example of the configuration shown in FIG. 6, tables are
respectively configured for a race, a sex, an age, and a physique
are configured, but the tables may be configured in various forms
as shown in FIGS. 7A to 9D instead of configuring tables for a
race, a sex, an age, and a physique, respectively.
[0098] For example, when only the race of the subject can be
estimated on the basis of the subject information input through the
image analyzing unit 331 or the user input unit 332, the reference
value calculating table for each race shown in FIG. 7A is used.
When the race can not be determined, data for "common" is used.
[0099] When the race and sex of the subject can be
estimated/determined on the basis of the subject information input
through the image analyzing unit 331 or the user input unit 332,
the reference value calculating table for each race and sex shown
in FIG. 7B is used. When the subject is included in an Asian ethnic
group and male, then, data in a column A shown in FIG. 7B is used.
On the other hand, when the sex of the subject is
estimated/determined to be female while the race of the subject can
not be identified, data in a column B shown in FIG. 7B which
represents the race for common and the sex for female is used.
[0100] Likewise, when the age group of the subject can be
estimated/determined additionally, the reference value calculating
table for each race, sex, and age shown in FIG. 8C is used. When it
is known that the subject is in an Asian ethnic group, male, and
twelve years old, data in a row C shown in FIG. 8C is used, and
when the age group can not be estimated for any reason, data in a
row D shown in FIG. 8C is used. Likewise, when the physique of the
subject can be estimated/determined additionally, the reference
value calculating table for each race, sex, age, and physique shown
in FIG. 9D is used for calculating an optimal reference value
Wref=(Wref+.DELTA.Wrefb) to (Wref-.DELTA.Wrerfs).
[0101] As described above, it is possible to acquire an appropriate
face size reference value Wref by obtaining the race, sex, age, and
physique of the subject on the basis of the image analysis or
user's input information, and the distance Df to the subject can be
calculated precisely further by using the calculated reference
value Wref. For the process of the application of the reference
value Wref or the process of the calculation of the distance Df to
the subject, one between the horizontal width of a face and the
vertical length of a face may be used or the both the horizontal
width and vertical length of a face may be used. Moreover, the tilt
of the subject may be considered for the processes.
[0102] As described above, an identifier such as a face icon is
displayed in a position corresponding to the calculated distance on
the distance indicator displayed in the display unit as described
with reference to FIG. 3 on the basis of the distance Df to the
subject which is calculated on the basis of the face size of the
subject. When a plurality of faces are included in the image, the
distances corresponding to the faces are respectively calculated,
and icons indifferent colors corresponding to each face and face
identification marks for each face are displayed.
[0103] The display position of the icon corresponding to the
distance indicator is determined for being displayed by performing
a normalization process which correlates the calculated distance Df
that is calculated on the basis of the face size with the display
distance of the indicator displayed in the display unit.
[0104] Next, the sequence of processes performed in the imaging
apparatus according to an embodiment of the invention will be
described with reference to a flowchart shown in FIG. 10. The
processes shown in the flowchart of FIG. 10 are performed by
controlling constituent units such as the face detecting unit 130
under the control of the control unit 110 of the imaging apparatus
shown in FIG. 2. At first, in a step S101, a face region is
detected from an acquired image of the imaging apparatus by the
face detecting unit 130. As described above, for example, the face
region in the acquired image is determined by matching a template
in which information on the luminance distribution of the face is
recorded with an actual image for the detection.
[0105] Next, in a step S102, the distance to the detected face is
calculated. The above-described equation Equation 1.1, that is,
Df=Wref.times.(f/Wi).times.(Ww/Wf) is applied to a basic equation
for the calculation of the distance to the subject.
[0106] In the calculation process of the distance, as described
above, a face size reference value Wref corresponding to the ethnic
group, sex, age, and physique of the person may be used.
[0107] Next, in a step S103, the calculation process of the display
position of the distance identification information (face icon)
which is displayed corresponding to the distance indicator
displayed in the display unit on the basis of the calculated
distance information and the display process of the distance
identification information are performed. In the processes, the
display position is determined by performing a normalization
process which correlates the calculated distance Df calculated on
the basis of the face size with the display of the indicator, and
the display of the distance identification information is
performed.
[0108] Next, in a step S104, the calculated distance Df to the face
and the distance indicated by the indicator focal position
information are compared with each other, whereby it is determined
whether the current position (focal position) of the focus lens is
in the focal position for the face of the subject to which the
distance is calculated. To be more specific, as shown in FIG. 11,
it is verified whether the calculated distance Df to the face is in
proximity of a focal position Dp appearing on the indicator. In
other words, it is determined whether the calculated distance Df to
the face is in the allowed range Thr_min to Thr_max of focal
distances calculated from the focal position Dp.
[0109] When the distance Df to the face is determined to be in the
allowed range Thr_min to Thr_max of focal distances which is
calculated from the focal distance Dp, the process proceeds to a
step S105, and the distance identification information (face icon)
which is displayed additionally on the indicator is displayed
blinking. In addition, as described above with reference to FIG. 3,
the face region identification mark used as a focus frame is
displayed blinking. The use checks the in-focus display and then,
presses the shutter for photographing, whereby a precise
photographing can be performed.
[0110] On the other hand, when the distance Df to the face is
determined not to be in the allowed range Thr_min to Thr_max of
focal distances in the step S104 which is calculated from the focal
distance Dp, the blink process in the step S105 is not performed,
and the process ends. However, the processes of the steps S101 to
S105 are continuously performed while the imaging apparatus is set
to a manual focus mode, and when the result of the determination in
the step S104 becomes "Yes" in accordance with the movement of the
focus lens on the basis of the user's operation of the operation
unit, the blinking display of the icon and the like is performed in
the step S105, and the user operates the shutter at this moment,
whereby a focus-adjusted photographing can be performed.
[0111] In the above-described process flow, when the distance Df to
the face is determined to be in the allowed range Thr_min to
Thr_max of focal distances which is calculated from the focal
distance Dp, the process proceeds to the step S105, and the
distance identification information (face icon) which is displayed
additionally on the indicator is displayed blinking, but for
example, the in-focus notice may be performed by changing the
display color. In addition, the face region identification mark
used as a focus frame may be changed in display instead of
blinking.
[0112] Next, the sequence of processes performed in a case where a
plurality of faces are detected by the face detecting unit will be
described with reference to a flowchart shown in FIG. 12. The
processes shown in the flowchart of FIG. 12 are also performed by
controlling constituent units such as the face detecting unit 130
under the control of the control unit 110 of the imaging apparatus
shown in FIG. 2. At first, in a step S201, a face region is
detected from an acquired image of the imaging apparatus by the
face detecting unit 130. As described above, for example, the face
region in the acquired image is determined by matching a template
in which information on the luminance distribution of the face is
recorded with an actual image for the detection. In a step S202,
the number n of loops corresponding to the number n of faces
detected is set, and the processes in steps S203 to S207 are
performed.
[0113] In a step S203, the loop is started. In a step S204, the
distance to one face detected in the step S202 is calculated. The
above-described equation Equation 1.1, that is,
Df=Wref.times.(f/Wi).times.(Ww/Wf) is applied to a basic equation
for the calculation of the distance to the subject.
[0114] In the calculation process of the distance, as described
above, a face size reference value Wref corresponding to the ethnic
group, sex, age, and physique of the person may be used.
[0115] In a step S205, it is determined whether an icon is
displayed in a position on the indicator corresponding to the
position of the calculated distance. When the icon is not displayed
in the position, the process proceeds to a step S206, and the
distance identification information (face icon) is displayed in a
position on the indicator corresponding to the position of the
calculated distance. On the other hand, when the icon is determined
to be displayed in the position on the indicator corresponding to
the position of the calculated distance in the step S205, the
process proceeds to a next process of a step S207 without
performing the display process of the face icon of the step S206,
and the process proceeds to a process for the next loop. The
processes in the steps S203 to S207 are performed repeatedly the
number of times corresponding to the number of detected faces with
the target face to be processed changed one by one, and when the
process for all the faces are completed, the process ends.
[0116] In performing the loop of the steps S203 to S207, the order
of faces to be processed, for example, is set to be a descending
order in the detected face size. By this setting, a closely located
face is processed preferentially, and a face icon of a closely
located person is preferentially displayed on the indicator
additionally. As described above, when there are a plurality of
faces, the display process of icons for faces having low priority
levels is not performed, whereby the displays of the icons are
configured not to be overlapped with each other.
[0117] When a plurality of persons are photographed as described
above, a configuration in which a photographer previously selects a
face to which the distance is to be measured on a menu, inputs
selection information, and the control unit performs the distance
calculation and icon display processes only for the selected face
may be used. Moreover, for example, a configuration in which a
central area of the photographed image is set to a preferential
area and priority levels are sequentially assigned to areas from
the central position may be used.
[0118] Alternatively, a configuration in which only the largest
face or a face positioned the most closely to the center of the
image is set as a target face for the distance calculation and the
icon display and the process is performed only for the target face
may be used. In this case, since the number of detected face
becomes one, the number of the face icon on the indicator
corresponding thereto becomes one, whereby the photographer can
easily recognize the face icon without being confused in the
correspondence between faces and face icons.
[0119] When the photographer performs a rapid pan tilt, a face
displayed and detected in the monitor disappears from the field
angle, but in this case, the face icon on the indicator is removed
and initialized in accordance with the disappearance of the face.
However, in order to prevent an erroneous detection, the removal
process of the face icon is performed with a predetermined time
delay. After the icon is removed and the initialization is
performed, the face detection, distance calculation, and icon
display processes are re-performed on the basis of the acquired
image.
[0120] Examples of display of the indicator, the face icon, and the
face region identification mark which is used as an focus frame
have been described with reference to FIG. 3, but, as shown in FIG.
13, connection lines 521 and 522 that connect face icons and face
region identification marks may be displayed, so that the
correspondence among a face, a face region identification mark, and
a face icon can be easily identified. As shown in FIG. 14, the
distance information 531 and 532 may be displayed on the face
region identification marks that are used as focus frames.
Moreover, as shown in FIG. 15, when a side face between the
detected faces turns to the front side, a side face icon 551
corresponding to the side face may be displayed blinking to inform
the photographer of the movement. In addition, a configuration in
which face icons such as an adult, a child, male, female, and the
like are set as the types of face icons, and an icon in accordance
with a subject is selected for being displayed on the basis of the
detection information of the face detecting unit and the control
unit may be used.
[0121] The present invention has been described with reference to
exemplary embodiments thereof. However, it is apparent that any
modification or substitution may be made therein by those of
ordinary skill in the art without departing the gist of the present
invention. In other words, the present invention is disclosed as an
exemplary form, and therefore the exemplary embodiments should not
be considered for purposes of limitation. Therefore, in order to
determine the gist of the present invention, the appended claims
should be considered.
[0122] The series of processes described above can be performed by
using a configuration of hardware or software or a composite
configuration of hardware and software. When the processes are
performed by using a software configuration, a program recording a
process sequence may be executed by being installed to a memory of
a computer installed to a dedicated hardware or may be executed by
installing a program to a general-purpose computer capable of
performing various processes.
[0123] For example, the program may be recorded in a hard disk or a
ROM (Read Only Memory) as a recording medium in advance.
Alternatively, the program may be stored (recorded) temporarily or
permanently in a removable recording medium such as a flexible
disc, a CD-ROM (Compact Disc Read Only Memory), an MO (Magneto
optical) disc, a DVD (Digital Versatile Disc), a magnetic disk, and
a semiconductor memory. The removable recording medium may be
provided as so-called package software.
[0124] The program may be transmitted from a download site to a
computer by using wireless communication or wired communication
through a network such as a LAN (Local Area Network) and the
Internet, and the computer may receive the transmitted program and
installs the program to a recording medium such as an internal hard
disk, instead of being installed to the computer from the removable
recording medium as described above.
[0125] Various processes described above may be performed parallel
or independently in accordance with the processing capability of a
device for processing or as may be needed as well as performed in
time series in accordance with the description. A "system" in the
description above is a configuration of a logical combination of a
plurality of devices and is not limited to a case where the
constituent devices are in one body.
[0126] As described above, according to an embodiment of the
present invention, a face detecting process and a distance
calculating process are performed in an imaging apparatus, and a
distance identification information such as a face icon is
displayed in a position corresponding to the calculated distance in
the distance indicator which is displayed on a monitor screen or a
viewfinder. The photographer can intuitively recognize a distance
to the person from the display of the distance identification
information and also can easily recognize an approximate distance
to the person from the face icon displayed in the distance
indicator in a focus adjustment process by a manual focus
operation, whereby an imaging apparatus capable of performing the
manual focus control (focus adjustment) efficiently and precisely
is implemented.
[0127] According to an embodiment of the invention, a set color for
a face region identification mark which is configured to surround a
subject image displayed in a monitor or a viewfinder and the color
of the distance identification information such as a face icon
correspondently displayed in the distance indicator are configured
to be identical to each other or a connection line is connected for
displaying, and thus it is easy to recognize a distance to a target
subject even in a case where a plurality of faces are displayed in
the monitor, whereby an imaging apparatus capable of precisely
performing a focus adjustment operation on the target subject is
implemented.
[0128] It should be understood by those skilled in the art that
various modifications, combinations, sub-combinations and
alterations may occur depending on design requirements and other
factors insofar as they are within the scope of the appended claims
or the equivalents thereof.
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