U.S. patent application number 14/159676 was filed with the patent office on 2014-05-15 for indoor/outdoor scene detection using gps.
This patent application is currently assigned to Intellectual Ventures Fund 83 LLC. The applicant listed for this patent is Intellectual Ventures Fund 83 LLC. Invention is credited to Robert M. Guidash, Wayne E. Prentice, Frank Razavi.
Application Number | 20140132796 14/159676 |
Document ID | / |
Family ID | 44168235 |
Filed Date | 2014-05-15 |
United States Patent
Application |
20140132796 |
Kind Code |
A1 |
Prentice; Wayne E. ; et
al. |
May 15, 2014 |
INDOOR/OUTDOOR SCENE DETECTION USING GPS
Abstract
A digital camera system, comprising: a digital image sensor; an
optical system for forming an image of a scene onto the digital
image sensor; a global positioning system sensor; a
processor-accessible memory system; and a processor. The processor
performs the steps of: analyzing a signal from the global
positioning system sensor to determine whether the digital camera
system is indoors or outdoors; capturing an input digital image of
the scene using the digital image sensor; processing the input
digital image responsive to whether the digital camera system is
indoors or outdoors; and storing the processed digital image in the
processor-accessible memory system.
Inventors: |
Prentice; Wayne E.; (Honeoye
Falls, NY) ; Guidash; Robert M.; (Rochester, NY)
; Razavi; Frank; (Rochester, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Intellectual Ventures Fund 83 LLC |
Las Vegas |
NV |
US |
|
|
Assignee: |
Intellectual Ventures Fund 83
LLC
Las Vegas
NV
|
Family ID: |
44168235 |
Appl. No.: |
14/159676 |
Filed: |
January 21, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12769680 |
Apr 29, 2010 |
8665340 |
|
|
14159676 |
|
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Current U.S.
Class: |
348/223.1 ;
348/222.1 |
Current CPC
Class: |
H04N 5/232 20130101;
G03B 17/18 20130101; G03B 7/08 20130101; H04N 5/23229 20130101;
H04N 9/735 20130101; H04N 5/232939 20180801; H04N 5/232933
20180801; H04N 5/23245 20130101 |
Class at
Publication: |
348/223.1 ;
348/222.1 |
International
Class: |
H04N 5/232 20060101
H04N005/232; H04N 9/73 20060101 H04N009/73 |
Claims
1. An image capture system comprising: a digital image sensor; an
optical system configured to form an image of a scene onto the
digital image sensor; a global positioning system sensor; a
processor-accessible memory system; a processor configured to
perform operations comprising: analyzing a signal from the global
positioning system sensor to determine whether the image capture
system is indoors or outdoors, wherein the analyzing comprises:
determining a geographic location and an altitude by analyzing the
signal from the global positioning system sensor; determining a
known ground level altitude at the determined geographic location
from a topology database that provides an indication of ground
elevation as a function of geographic location; determining a
likelihood that the digital camera system is indoors based on a
difference between the determined altitude and the known ground
level altitude at the determined geographic location; capturing a
digital image of the scene using the digital image sensor;
processing the digital image responsive to whether the digital
camera system is determined to likely be indoors or outdoors; and
storing the digital image in the processor-accessible memory
system.
2. The image capture system of claim 1, wherein the processor is
further configured to perform operations comprising setting an
outdoor photography mode when it is determined that the image
capture system is outdoors.
3. The image capture system of claim 1, wherein the signal from the
global positioning system sensor is analyzed by determining a
geographic location, and wherein the processor is further
configured to perform operations comprising: determining an image
capture date and time; and determining a type of lighting
responsive to the determined geographic location and the determined
image capture date and time.
4. The image capture system of claim 1, wherein the processing the
digital image includes adjusting at least one parameter of an image
processing operation responsive to whether the image capture system
is likely indoors or outdoors.
5. The image capture system of claim 4, wherein the processor is
further configured to perform operations comprising adjusting a
parameter for a white balance operation responsive to whether the
image capture system is likely indoors or outdoors.
6. The image capture system of claim 4, wherein the processor is
further configured to perform operations comprising adjusting a
parameter for a color correction operation responsive to whether
the image capture system is likely indoors or outdoors.
7. The image capture system of claim 1, wherein the processing the
digital image includes determining metadata to be associated with
the stored digital image providing an indication of whether the
image capture system is likely indoors or outdoors.
8. The image capture system of claim 1, wherein the processor is
further configured to perform operations comprising adjusting one
or more image capture settings used in the capturing the digital
image responsive to whether the image capture system is likely
indoors or outdoors.
9. The image capture system of claim 1, wherein the processor is
further configured to perform operations comprising: analyzing a
signal from the global positioning system sensor to determine
whether the image capture system is moving; and adjusting one or
camera settings responsive to whether the image capture system is
moving.
10. A method comprising: determining a geographic location and an
altitude by analyzing a signal from a global positioning system
sensor; determining a known ground level altitude at the determined
geographic location from a topology database that provides an
indication of ground elevation as a function of geographic
location; determining a likelihood that an image capture system is
indoors based on a difference between the determined altitude and
the known ground level altitude at the determined geographic
location; capturing a digital image of the scene using a digital
image sensor; processing the digital image responsive to whether
the image capture system is determined to likely be indoors or
outdoors; and storing the digital image in a processor-accessible
memory system.
11. The method of claim 10, further comprising setting an outdoor
photography mode when it is determined that the image capture
system is outdoors.
12. The image capture system of claim 1, further comprising:
determining an image capture date and time; and determining a type
of lighting responsive to the determined geographic location and
the determined image capture date and time.
13. The method of claim 10, further comprising adjusting at least
one parameter of an image processing operation responsive to
whether the image capture system is likely indoors or outdoors.
14. The method of claim 13, further comprising adjusting a
parameter for a white balance operation responsive to whether the
image capture system is likely indoors or outdoors.
15. The method of claim 13, further comprising adjusting a
parameter for a color correction operation responsive to whether
the image capture system is likely indoors or outdoors.
16. The method of claim 10, further comprising: analyzing a signal
from the global positioning system sensor to determine whether the
image capture system is moving; and adjusting one or camera
settings responsive to whether the image capture system is
moving.
17. A non-transitory computer readable medium having instructions
stored thereon, the instructions comprising: determining a
geographic location and an altitude by analyzing a signal from a
global positioning system sensor; determining a known ground level
altitude at the determined geographic location from a topology
database that provides an indication of ground elevation as a
function of geographic location; determining a likelihood that an
image capture system is indoors based on a difference between the
determined altitude and the known ground level altitude at the
determined geographic location; capturing a digital image of the
scene using a digital image sensor; processing the digital image
responsive to whether the image capture system is determined to
likely be indoors or outdoors; and storing the digital image in a
processor-accessible memory system.
18. The computer readable medium of claim 17, further comprising
determining metadata to be associated with the stored digital image
providing an indication of whether the image capture system is
likely indoors or outdoors.
19. The computer readable medium of claim 17, further comprising
adjusting one or more image capture settings used in the capturing
the digital image responsive to whether the image capture system is
likely indoors or outdoors.
20. The computer readable medium of claim 17, further comprising:
analyzing a signal from the global positioning system sensor to
determine whether the image capture system is moving; and adjusting
one or camera settings responsive to whether the image capture
system is moving.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This application is a Continuation of U.S. application Ser.
No. 12/769,680, filed Apr. 29, 2010, incorporated herein by
reference in its entirety.
FIELD
[0002] The invention relates generally to a digital camera system,
and more particularly to a digital camera system that determines
whether it is indoors or outdoors by analyzing a signal from a
global positioning system sensor.
BACKGROUND
[0003] Automatic exposure control of a camera is generally achieved
by detecting the brightness of an object with a light metering
device, determining an exposure value based on said object
brightness and the sensitivity of the imaging system, and driving
the diaphragm and the shutter according to said exposure value.
However, in such cases where the exposure determination is based
solely on the object brightness and the sensitivity of the imaging
system, the resulting photographs often do not convey the
appearance that the photographer intended to communication. For
example, a photographer may intend that a photograph captured at
dusk would convey a corresponding appearance. However, such
photographs are often reproduced with an unnatural appearance where
the image brightness has been adjusted to make the light level be
the same as a daytime photograph.
[0004] This has led to the development of various photography modes
that can be user-selected in different photography environments
according to the photographer's preferences. For example, different
photography modes are offered on some digital cameras that have
optimized for typical outdoor daylight-illuminated environments,
typical indoor tungsten-illuminated environments and other
specialized cases such as sunset environments.
[0005] Some attempts have been made to automate the selection of
appropriate photography modes. One example of this process can be
found in U.S. Pat. No. 5,086,314 to Aoki et al., entitled "Exposure
control apparatus for camera," which teaches using a reduced
exposure level when it is determined that a photograph is being
captured at dusk in order to better convey the appearance of a dusk
scene.
[0006] U.S. Pat. No. 5,913,078 to Kimura et al., entitled "Camera
utilizing a satellite positioning system," teaches a camera adapted
to determine position information using a Global Positioning System
(GPS) sensor in order to record a geographic location together with
a photographed image.
[0007] U.S. Pat. No. 6,895,368 to Murakami, entitled "Maintenance
information supply system with a host computer and an electronic
device," discloses a maintenance information supply system in which
an electronic device terminal includes a GPS sensor for obtaining
the present location information. The maintenance information
supply system calculates maintenance information responsive to the
determined position. The system determines that it is located at an
indoor location when a valid GPS signal is not detected.
SUMMARY
[0008] The present invention represents a digital camera system,
comprising:
[0009] a digital image sensor;
[0010] an optical system for forming an image of a scene onto the
digital image sensor;
[0011] a global positioning system sensor;
[0012] a processor-accessible memory system;
[0013] a processor for performing the steps of:
[0014] analyzing a signal from the global positioning system sensor
to determine whether the digital camera system is indoors or
outdoors;
[0015] capturing an input digital image of the scene using the
digital image sensor;
[0016] processing the input digital image responsive to whether the
digital camera system is indoors or outdoors; and
[0017] storing the processed digital image in the
processor-accessible memory system.
[0018] This invention has the advantage that it can automatically
adjust various camera settings to provide improved image quality by
determining whether the digital camera is being operated indoors or
outdoors.
[0019] It has the further advantage that camera settings can be
adjusted responsive to a determined geographic location and an
image capture date and time.
[0020] It has the additional advantage that a lighting type can
automatically be determined using a geographical database, and can
be used to further improve the image quality by adjusting various
camera settings in response to the determined lighting type.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a high-level diagram showing the components of a
digital camera system;
[0022] FIG. 2 is a flow diagram depicting typical image processing
operations used to process digital images in a digital camera;
[0023] FIG. 3 is a flow chart showing a method for determining
whether a digital camera is operating indoors or outdoors and
adjusting camera settings accordingly;
[0024] FIG. 4 is a flow chart giving more detail for the analyze
GPS signal step of FIG. 3 according to one embodiment of the
present invention;
[0025] FIG. 5 is a flow chart giving more detail for the determine
outdoor camera settings step 225 of FIG. 3 according to one
embodiment of the present invention; and
[0026] FIG. 6 is a flow chart giving more detail for the determine
indoor camera settings step 235 of FIG. 3 according to one
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] In the following description, a preferred embodiment of the
present invention will be described in terms that would ordinarily
be implemented as a software program. Those skilled in the art will
readily recognize that the equivalent of such software can also be
constructed in hardware. Because image manipulation algorithms and
systems are well known, the present description will be directed in
particular to algorithms and systems forming part of, or
cooperating more directly with, the system and method in accordance
with the present invention. Other aspects of such algorithms and
systems, and hardware or software for producing and otherwise
processing the image signals involved therewith, not specifically
shown or described herein, can be selected from such systems,
algorithms, components and elements known in the art. Given the
system as described according to the invention in the following
materials, software not specifically shown, suggested or described
herein that is useful for implementation of the invention is
conventional and within the ordinary skill in such arts.
[0028] Still further, as used herein, a computer program for
performing the method of the present invention can be stored in a
computer readable storage medium, which can include, for example;
magnetic storage media such as a magnetic disk (such as a hard
drive or a floppy disk) or magnetic tape; optical storage media
such as an optical disc, optical tape, or machine readable bar
code; solid state electronic storage devices such as random access
memory (RAM), or read only memory (ROM); or any other physical
device or medium employed to store a computer program having
instructions for controlling one or more computers to practice the
method according to the present invention.
[0029] The invention is inclusive of combinations of the
embodiments described herein. References to "a particular
embodiment" and the like refer to features that are present in at
least one embodiment of the invention. Separate references to "an
embodiment" or "particular embodiments" or the like do not
necessarily refer to the same embodiment or embodiments; however,
such embodiments are not mutually exclusive, unless so indicated or
as are readily apparent to one of skill in the art. The use of
singular or plural in referring to the "method" or "methods" and
the like is not limiting. It should be noted that, unless otherwise
explicitly noted or required by context, the word "or" is used in
this disclosure in a non-exclusive sense.
[0030] Because digital cameras employing imaging devices and
related circuitry for signal capture and processing, and display
are well known, the present description will be directed in
particular to elements forming part of, or cooperating more
directly with, the method and apparatus in accordance with the
present invention. Elements not specifically shown or described
herein are selected from those known in the art. Certain aspects of
the embodiments to be described are provided in software. Given the
system as shown and described according to the invention in the
following materials, software not specifically shown, described or
suggested herein that is useful for implementation of the invention
is conventional and within the ordinary skill in such arts.
[0031] The following description of a digital camera will be
familiar to one skilled in the art. It will be obvious that there
are many variations of this embodiment that are possible and are
selected to reduce the cost, add features or improve the
performance of the camera.
[0032] FIG. 1 depicts a block diagram of a digital photography
system, including a digital camera 10 in accordance with the
present invention. Preferably, the digital camera 10 is a portable
battery operated device, small enough to be easily handheld by a
user when capturing and reviewing images. The digital camera 10
produces digital images that are stored as digital image files
using image memory 30. The phrase "digital image" or "digital image
file", as used herein, refers to any digital image file, such as a
digital still image or a digital video file.
[0033] In some embodiments, the digital camera 10 captures both
motion video images and still images. The digital camera 10 can
also include other functions, including, but not limited to, the
functions of a digital music player (e.g. an MP3 player), a mobile
telephone, a GPS receiver, or a programmable digital assistant
(PDA).
[0034] The digital camera 10 includes a lens 4 having an adjustable
aperture and adjustable shutter 6. In a preferred embodiment, the
lens 4 is a zoom lens and is controlled by zoom and focus motor
drives 8. The lens 4 focuses light from a scene (not shown) onto an
image sensor 14, for example, a single-chip color CCD or CMOS image
sensor. The lens 4 is one type optical system for forming an image
of the scene on the image sensor 14. In other embodiments, the
optical system may use a fixed focal length lens with either
variable or fixed focus.
[0035] The output of the image sensor 14 is converted to digital
form by Analog Signal Processor (ASP) and Analog-to-Digital (A/D)
converter 16, and temporarily stored in buffer memory 18. The image
data stored in buffer memory 18 is subsequently manipulated by a
processor 20, using embedded software programs (e.g. firmware)
stored in firmware memory 28. In some embodiments, the software
program is permanently stored in firmware memory 28 using a read
only memory (ROM). In other embodiments, the firmware memory 28 can
be modified by using, for example, Flash EPROM memory. In such
embodiments, an external device can update the software programs
stored in firmware memory 28 using the wired interface 38 or the
wireless modem 50. In such embodiments, the firmware memory 28 can
also be used to store image sensor calibration data, user setting
selections and other data which must be preserved when the camera
is turned off. In some embodiments, the processor 20 includes a
program memory (not shown), and the software programs stored in the
firmware memory 28 are copied into the program memory before being
executed by the processor 20.
[0036] It will be understood that the functions of processor 20 can
be provided using a single programmable processor or by using
multiple programmable processors, including one or more digital
signal processor (DSP) devices. Alternatively, the processor 20 can
be provided by custom circuitry (e.g., by one or more custom
integrated circuits (ICs) designed specifically for use in digital
cameras), or by a combination of programmable processor(s) and
custom circuits. It will be understood that connectors between the
processor 20 from some or all of the various components shown in
FIG. 1 can be made using a common data bus. For example, in some
embodiments the connection between the processor 20, the buffer
memory 18, the image memory 30, and the firmware memory 28 can be
made using a common data bus.
[0037] The processed images are then stored using the image memory
30. It is understood that the image memory 30 can be any form of
memory known to those skilled in the art including, but not limited
to, a removable Flash memory card, internal Flash memory chips,
magnetic memory, or optical memory. In some embodiments, the image
memory 30 can include both internal Flash memory chips and a
standard interface to a removable Flash memory card, such as a
Secure Digital (SD) card. Alternatively, a different memory card
format can be used, such as a micro SD card, Compact Flash (CF)
card, MultiMedia Card (MMC), xD card or Memory Stick.
[0038] The image sensor 14 is controlled by a timing generator 12,
which produces various clocking signals to select rows and pixels
and synchronizes the operation of the ASP and A/D converter 16. The
image sensor 14 can have, for example, 12.4 megapixels
(4088.times.3040 pixels) in order to provide a still image file of
approximately 4000.times.3000 pixels. To provide a color image, the
image sensor is generally overlaid with a color filter array, which
provides an image sensor having an array of pixels that include
different colored pixels. The different color pixels can be
arranged in many different patterns. As one example, the different
color pixels can be arranged using the well-known Bayer color
filter array, as described in commonly assigned U.S. Pat. No.
3,971,065, "Color imaging array" to Bayer, the disclosure of which
is incorporated herein by reference. As a second example, the
different color pixels can be arranged as described in commonly
assigned U.S. Patent Application Publication 2005/191729, filed on
Jul. 28, 2007 and titled "Image sensor with improved light
sensitivity" to Compton and Hamilton, the disclosure of which is
incorporated herein by reference. These examples are not limiting,
and many other color patterns may be used.
[0039] It will be understood that the image sensor 14, timing
generator 12, and ASP and A/D converter 16 can be separately
fabricated integrated circuits, or they can be fabricated as a
single integrated circuit as is commonly done with CMOS image
sensors. In some embodiments, this single integrated circuit can
perform some of the other functions shown in FIG. 1, including some
of the functions provided by processor 20.
[0040] The image sensor 14 is effective when actuated in a first
mode by timing generator 12 for providing a motion sequence of
lower resolution sensor image data, which is used when capturing
video images and also when previewing a still image to be captured,
in order to compose the image. This preview mode sensor image data
can be provided as HD resolution image data, for example, with
1280.times.720 pixels, or as VGA resolution image data, for
example, with 640.times.480 pixels, or using other resolutions
which have significantly fewer columns and rows of data, compared
to the resolution of the image sensor.
[0041] The preview mode sensor image data can be provided by
combining values of adjacent pixels having the same color, or by
eliminating some of the pixel values, or by combining some color
pixel values while eliminating other color pixel values. The
preview mode image data can be processed as described in commonly
assigned U.S. Pat. No. 6,292,218 to Parulski, et al., entitled
"Electronic camera for initiating capture of still images while
previewing motion images," which is incorporated herein by
reference.
[0042] The image sensor 14 is also effective when actuated in a
second mode by timing generator 12 for providing high resolution
still image data. This final mode sensor image data is provided as
high resolution output image data, which for scenes having a high
illumination level includes all of the pixels of the image sensor,
and can be, for example, a 12 megapixel final image data having
4000.times.3000 pixels. At lower illumination levels, the final
sensor image data can be provided by "binning" some number of
like-colored pixels on the image sensor, in order to increase the
signal level and thus the "ISO speed" of the sensor.
[0043] The zoom and focus motor drivers 8 are controlled by control
signals supplied by the processor 20, to provide the appropriate
focal length setting and to focus the scene onto the image sensor
14. The exposure level of the image sensor 14 is controlled by
controlling the f/number and exposure time of the adjustable
aperture and adjustable shutter 6, the exposure period of the image
sensor 14 via the timing generator 12, and the gain (i.e., ISO
speed) setting of the ASP and A/D converter 16. The processor 20
also controls a flash 2 which can illuminate the scene.
[0044] The lens 4 of the digital camera 10 can be focused in the
first mode by using "through-the-lens" autofocus, as described in
commonly-assigned U.S. Pat. No. 5,668,597, entitled "Electronic
Camera with Rapid Automatic Focus of an Image upon a Progressive
Scan Image Sensor" to Parulski et al., which is incorporated herein
by reference. This is accomplished by using the zoom and focus
motor drivers 8 to adjust the focus position of the lens 4 to a
number of positions ranging between a near focus position to an
infinity focus position, while the processor 20 determines the
closest focus position which provides a peak sharpness value for a
central portion of the image captured by the image sensor 14. The
focus distance which corresponds to the closest focus position can
then be utilized for several purposes, such as automatically
setting an appropriate scene mode, and can be stored as metadata in
the image file, along with other lens and camera settings.
[0045] The processor 20 produces menus and low resolution color
images that are temporarily stored in display memory 36 and are
displayed on the image display 32. The image display 32 is
typically an active matrix color liquid crystal display (LCD),
although other types of displays, such as organic light emitting
diode (OLED) displays, can be used. A video interface 44 provides a
video output signal from the digital camera 10 to a video display
46, such as a flat panel HDTV display. In preview mode, or video
mode, the digital image data from buffer memory 18 is manipulated
by processor 20 to form a series of motion preview images that are
displayed, typically as color images, on the image display 32. In
review mode, the images displayed on the image display 32 are
produced using the image data from the digital image files stored
in image memory 30.
[0046] The graphical user interface displayed on the image display
32 is controlled in response to user input provided by user
controls 34. The user controls 34 are used to select various camera
modes, such as video capture mode, still capture mode, and review
mode, and to initiate capture of still images and recording of
motion images. In some embodiments, the first mode described above
(i.e. still preview mode) is initiated when the user partially
depresses a shutter button, which is one of the user controls 34,
and the second mode (i.e., still image capture mode) is initiated
when the user fully depresses the shutter button. The user controls
34 are also used to turn on the camera, control the lens 4, and
initiate the picture taking process. User controls 34 typically
include some combination of buttons, rocker switches, joysticks, or
rotary dials. In some embodiments, some of the user controls 34 are
provided by using a touch screen overlay on the image display 32.
In other embodiments, additional status displays or images displays
can be used.
[0047] The camera modes that can be selected using the user
controls 34 include a "timer" mode. When the "timer" mode is
selected, a short delay (e.g., 10 seconds) occurs after the user
fully presses the shutter button, before the processor 20 initiates
the capture of a still image.
[0048] A global position system (GPS) sensor 25 on the digital
camera 10 can be used to provide geographical location information
which is used for implementing the present invention, as will be
described later with respect to FIG. 3. GPS sensors 25 are
well-known in the art and operate by sensing signals emitted from
GPS satellites. A GPS sensor 25 receives highly accurate time
signals transmitted from GPS satellites. The precise geographical
location of the GPS sensor 25 can be determined by analyzing time
differences between the signals received from a plurality of GPS
satellites positioned at known locations.
[0049] An audio codec 22 connected to the processor 20 receives an
audio signal from a microphone 24 and provides an audio signal to a
speaker 26. These components can be to record and playback an audio
track, along with a video sequence or still image. If the digital
camera 10 is a multi-function device such as a combination camera
and mobile phone, the microphone 24 and the speaker 26 can be used
for telephone conversation.
[0050] In some embodiments, the speaker 26 can be used as part of
the user interface, for example to provide various audible signals
which indicate that a user control has been depressed, or that a
particular mode has been selected. In some embodiments, the
microphone 24, the audio codec 22, and the processor 20 can be used
to provide voice recognition, so that the user can provide a user
input to the processor 20 by using voice commands, rather than user
controls 34. The speaker 26 can also be used to inform the user of
an incoming phone call. This can be done using a standard ring tone
stored in firmware memory 28, or by using a custom ring-tone
downloaded from a wireless network 58 and stored in the image
memory 30. In addition, a vibration device (not shown) can be used
to provide a silent (e.g., non audible) notification of an incoming
phone call.
[0051] The processor 20 also provides additional processing of the
image data from the image sensor 14, in order to produce rendered
sRGB image data which is compressed and stored within a "finished"
image file, such as a well-known Exif-JPEG image file, in the image
memory 30.
[0052] The digital camera 10 can be connected via the wired
interface 38 to an interface/recharger 48, which is connected to a
computer 40, which can be a desktop computer or portable computer
located in a home or office. The wired interface 38 can conform to,
for example, the well-known USB 2.0 interface specification. The
interface/recharger 48 can provide power via the wired interface 38
to a set of rechargeable batteries (not shown) in the digital
camera 10.
[0053] The digital camera 10 can include a wireless modem 50, which
interfaces over a radio frequency band 52 with the wireless network
58. The wireless modem 50 can use various wireless interface
protocols, such as the well-known Bluetooth wireless interface or
the well-known 802.11 wireless interface. The computer 40 can
upload images via the Internet 70 to a photo service provider 72,
such as the Kodak Gallery. Other devices (not shown) can access the
images stored by the photo service provider 72.
[0054] In alternative embodiments, the wireless modem 50
communicates over a radio frequency (e.g. wireless) link with a
mobile phone network (not shown), such as a 3GSM network, which
connects with the Internet 70 in order to upload digital image
files from the digital camera 10. These digital image files can be
provided to the computer 40 or the photo service provider 72.
[0055] FIG. 2 is a flow diagram depicting typical image processing
operations performed by the processor 20 in the digital camera 10
(FIG. 1) in order to process color sensor data 100 from the image
sensor 14 output by the ASP and A/D converter 16. In some
embodiments, the processing parameters used by the processor 20 to
manipulate the color sensor data 100 for a particular digital image
are determined by various user settings 175, which can be selected
via the user controls 34 in response to menus displayed on the
image display 32.
[0056] The color sensor data 100 which has been digitally converted
by the ASP and A/D converter 16 is manipulated by a white balance
step 95. In some embodiments, this processing can be performed
using the methods described in commonly-assigned U.S. Pat. No.
7,542,077 to Miki, entitled "White balance adjustment device and
color identification device", the disclosure of which is herein
incorporated by reference. The white balance can be adjusted in
response to a white balance setting 90, which can be manually set
by a user, or which can be automatically set by the camera.
[0057] The color image data is then manipulated by a noise
reduction step 105 in order to reduce noise from the image sensor
14. In some embodiments, this processing can be performed using the
methods described in commonly-assigned U.S. Pat. No. 6,934,056 to
Gindele et al., entitled "Noise cleaning and interpolating sparsely
populated color digital image using a variable noise cleaning
kernel," the disclosure of which is herein incorporated by
reference. The level of noise reduction can be adjusted in response
to an ISO setting 110, so that more filtering is performed at
higher ISO exposure index setting.
[0058] The color image data is then manipulated by a demosaicing
step 115, in order to provide red, green and blue (RGB) image data
values at each pixel location. Algorithms for performing the
demosaicing step 115 are commonly known as color filter array (CFA)
interpolation algorithms or "deBayering" algorithms. In one
embodiment of the present invention, the demosaicing step 115 can
use the luminance CFA interpolation method described in
commonly-assigned U.S. Pat. No. 5,652,621, entitled "Adaptive color
plane interpolation in single sensor color electronic camera," to
Adams et al., the disclosure of which is incorporated herein by
reference. The demosaicing step 115 can also use the chrominance
CFA interpolation method described in commonly-assigned U.S. Pat.
No. 4,642,678, entitled "Signal processing method and apparatus for
producing interpolated chrominance values in a sampled color image
signal", to Cok, the disclosure of which is herein incorporated by
reference.
[0059] In some embodiments, the user can select between different
pixel resolution modes, so that the digital camera can produce a
smaller size image file. Multiple pixel resolutions can be provided
as described in commonly-assigned U.S. Pat. No. 5,493,335, entitled
"Single sensor color camera with user selectable image record
size," to Parulski et al., the disclosure of which is herein
incorporated by reference. In some embodiments, a resolution mode
setting 120 can be selected by the user to be full size (e.g.
3,000.times.2,000 pixels), medium size (e.g. 1,500.times.1000
pixels) or small size (750.times.500 pixels).
[0060] The color image data is color corrected in color correction
step 125. In some embodiments, the color correction is provided
using a 3.times.3 linear space color correction matrix, as
described in commonly-assigned U.S. Pat. No. 5,189,511, entitled
"Method and apparatus for improving the color rendition of hardcopy
images from electronic cameras" to Parulski, et al., the disclosure
of which is incorporated herein by reference. In some embodiments,
different user-selectable color modes can be provided by storing
different color matrix coefficients in firmware memory 28 of the
digital camera 10. For example, four different color modes can be
provided, so that the color mode setting 130 is used to select one
of the following color correction matrices:
[0061] Setting 1 (normal color reproduction)
[ R out G out B out ] = [ 1.50 - 0.30 - 0.20 - 0.40 1.80 - 0.40 -
0.20 - 0.20 1.40 ] [ R in G in B in ] ( 1 ) ##EQU00001##
[0062] Setting 2 (saturated color reproduction)
[ R out G out B out ] = [ 2.00 - 0.60 - 0.40 - 0.80 2.60 - 0.80 -
0.40 - 0.40 1.80 ] [ R in G in B in ] ( 2 ) ##EQU00002##
[0063] Setting 3 (de-saturated color reproduction)
[ R out G out B out ] = [ 1.25 - 0.15 - 0.10 - 0.20 1.40 - 0.20 -
0.10 - 0.10 1.20 ] [ R in G in B in ] ( 3 ) ##EQU00003##
[0064] Setting 4 (monochrome)
[ R out G out B out ] = [ 0.30 0.60 0.10 0.30 0.60 0.10 0.30 0.60
0.10 ] [ R in G in B in ] ( 4 ) ##EQU00004##
[0065] In other embodiments, a three-dimensional lookup table can
be used to perform the color correction step 125.
[0066] The color image data is also manipulated by a tone scale
correction step 135. In some embodiments, the tone scale correction
step 135 can be performed using a one-dimensional look-up table as
described in U.S. Pat. No. 5,189,511, cited earlier. In some
embodiments, a plurality of tone scale correction look-up tables is
stored in the firmware memory 28 in the digital camera 10. These
can include look-up tables which provide a "normal" tone scale
correction curve, a "high contrast" tone scale correction curve,
and a "low contrast" tone scale correction curve. A user selected
contrast setting 140 is used by the processor 20 to determine which
of the tone scale correction look-up tables to use when performing
the tone scale correction step 135.
[0067] The color image data is also manipulated by an image
sharpening step 145. In some embodiments, this can be provided
using the methods described in commonly-assigned U.S. Pat. No.
6,192,162 entitled "Edge enhancing colored digital images" to
Hamilton, et al., the disclosure of which is incorporated herein by
reference. In some embodiments, the user can select between various
sharpening settings, including a "normal sharpness" setting, a
"high sharpness" setting, and a "low sharpness" setting. In this
example, the processor 20 uses one of three different edge boost
multiplier values, for example 2.0 for "high sharpness", 1.0 for
"normal sharpness", and 0.5 for "low sharpness" levels, responsive
to a sharpening setting 150 selected by the user of the digital
camera 10.
[0068] The color image data is also manipulated by an image
compression step 155. In some embodiments, the image compression
step 155 can be provided using the methods described in
commonly-assigned U.S. Pat. No. 4,774,574, entitled "Adaptive block
transform image coding method and apparatus" to Daly et al., the
disclosure of which is incorporated herein by reference. In some
embodiments, the user can select between various compression
settings. This can be implemented by storing a plurality of
quantization tables, for example, three different tables, in the
firmware memory 28 of the digital camera 10. These tables provide
different quality levels and average file sizes for the compressed
digital image file 180 to be stored in the image memory 30 of the
digital camera 10. A user selected compression mode setting 160 is
used by the processor 20 to select the particular quantization
table to be used for the image compression step 155 for a
particular image.
[0069] The compressed color image data is stored in a digital image
file 180 using a file formatting step 165. The image file can
include various metadata 170. Metadata 170 is any type of
information that relates to the digital image, such as the model of
the camera that captured the image, the size of the image, the date
and time the image was captured, and various camera settings, such
as the lens focal length, the exposure time and f-number of the
lens, and whether or not the camera flash fired. In a preferred
embodiment, all of this metadata 170 is stored using standardized
tags within the well-known Exif-JPEG still image file format. In a
preferred embodiment of the present invention, the metadata 170
includes information about camera settings 185. The camera settings
185 would include many different types of information such as
exposure time, lens F/#, color correction settings, image size,
compression level and indications of the user settings 175.
[0070] In photography, it is often desirable to have knowledge
about the image capture environment in which a picture is being
captured in order to choose the most appropriate camera settings.
Digital cameras commonly adjust various camera settings in response
to information provided by various environmental sensors that sense
environmental attributes such as scene brightness, illuminant color
temperature and subject distance, as well as user-provided
information specified by user settings 175.
[0071] One particular aspect of the image capture environment that
is relevant to determining various camera settings is whether an
image is captured in an indoor or outdoor setting. For example,
digital cameras commonly adjust parameters used in image processing
operations such as the white balance step 95 and the color
correction step 125 in response to information about the scene
illuminant. Typically, the information about the scene illuminant
is either provided by user settings 175 or by evaluating a measured
distribution of scene colors. The process of estimating the scene
illuminant can be more accurate if it is aware of the
indoor/outdoor status. For example, some artificial light sources
can be excluded as candidate scene illuminants if the image capture
conditions are known to be outdoors. This would improve images of
foliage under daylight capture conditions which can sometimes be
confused with indoor fluorescent lighting. Likewise, knowledge of
the indoor/outdoor status can improve the ability to distinguish
between a sunset scene and a tungsten-illuminated indoor scene.
[0072] Similarly, the process of determining an appropriate
exposure level can also be more accurate if it is aware of the
indoor/outdoor status. For example, if it is known that an image is
being captured outdoors, then a knowledge of the geographical
location and the date/time can be used to predict whether the image
is being captured under a likely sunset condition. When likely
sunset conditions are encountered, than a sunset mode can be
selected which can reduce the scene exposure to better preserve the
look of the sunset. Various color correction settings can also be
adjusted in order to enhance the color saturation of the
sunset.
[0073] Information about whether a scene was captured indoors or
outdoors can also provide value for image organization tasks. For
example, when a user is searching for a particular image, whether
an image was captured indoors or outdoors is an easily remembered
detail that can be useful for defining search conditions. If the
indoor/outdoor status is determined and associated with the image
as metadata, search software can use this information in the
searching process.
[0074] The present invention will now be described with reference
to FIG. 3, which is a flow chart showing a method for determining
whether a digital camera is operating indoors or outdoors by
analyzing a GPS signal 205 determined using the GPS sensor 25 (FIG.
1). The indoor/outdoor status is then used to control the
processing for a captured image.
[0075] A sense GPS signal step 200 is used to sense the GPS signal
205 using the GPS sensor 25. An analyze GPS signal step 210 is used
to analyze the GPS signal 205 to determine whether the digital
camera is outdoors 215 or indoors 220. More details of the analyze
GPS signal step 210 will be described later with reference to FIG.
4.
[0076] If the digital camera is determined to be outdoors 215, a
determine outdoor camera settings step 225 is used to determine
various camera settings 185 that are appropriate for outdoor
photography. Similarly, if the digital camera is determined to be
indoors 220, a determine indoor camera settings step 235 is used to
determine various camera settings 185 that are appropriate for
indoor photography.
[0077] The camera settings 185 can be set in any way known to those
skilled in the art. Particular camera settings 185 that are
commonly modified according to indoor and outdoor camera modes
would include capture settings (e.g., exposure time, lens F/#,
sensor ISO, whether to fire an electronic flash) and color
processing settings (e.g., white balance gain values, color
correction matrix coefficients). The determine outdoor camera
settings step 225 and the determine indoor camera settings step 235
are optionally responsive to the GPS signal 205. (Note that
optional features are shown using dashed lines in the accompanying
figures.) More details about the determine outdoor camera settings
step 225 and the determine indoor camera settings step 235
according to a preferred embodiment of the present invention will
be described later with reference to FIGS. 5 and 6,
respectively.
[0078] A capture digital image step 240 is used to capture an input
digital image 245 using the image sensor 14. The capture digital
image step 240 will typically be controlled responsive to various
capture settings such as exposure time, lens F/#, sensor ISO, and
whether to fire the electronic flash 2 (FIG. 1). As mentioned
earlier, some or all of these capture settings can be camera
settings 185 that are controlled responsive to whether the digital
camera is determined to be outdoors 215 or indoors 220.
[0079] A process digital image step 250 is used to process the
input digital image to form a processed digital image 255. The
process digital image step 250 typically applies a series of image
processing operations such as those that were described relative to
FIG. 2. Camera settings associated with any or all of the image
processing steps in the FIG. 2 imaging chain can be adjusted
responsive to whether the digital camera is determined to be
outdoors 215 or indoors 220. In one embodiment of the present
invention, color processing settings such as white balance gain
values and color correction matrices are adjusted to account for
the different scene illumination conditions that are encountered
for indoor and outdoor capture conditions.
[0080] A store digital image step 260 stores the processed digital
image 255 as digital image file 180. The store digital image step
260 will typically include the image compression step 155 and the
file formatting step 165 that were described with reference to FIG.
2. Various aspects of these steps are controlled by camera settings
185, any of which can be adjusted responsive to whether the digital
camera is determined to be outdoors 215 or indoors 220.
[0081] As discussed with reference to the file formatting step 165
in FIG. 2, metadata 170 giving an indication of the camera settings
185 is generally included in the digital image file 180. In a
preferred embodiment of the present invention, the metadata 170
includes an indication of whether the digital camera is determined
to be outdoors 215 or indoors 220. As mentioned earlier, this
metadata can be useful for various applications such as searching
for particular digital images using image organization
software.
[0082] FIG. 4 shows a flow chart giving more detail for the analyze
GPS signal step 210 of FIG. 3 according to one embodiment of the
present invention. First, a weak GPS signal test 305 is used to
analyze the GPS signal 205. The transmission frequency for GPS
signals from GPS satellites is in the UHF radio band; therefore the
signals are attenuated or blocked by solid objects like walls of
buildings. The GPS system consists of about 26 satellites, of which
about 8 are visible to the receiver at any given point in time due
the orbits.
[0083] A typical GPS receiver can track multiple satellites and
maintains signal level data for each satellite it is currently
tracking. The location of the satellites is relative to the horizon
from the perspective of the receiver is also tracked. A significant
drop in signal level from satellites near zenith is an indication
overhead attenuation of the GPS signal, consistent with being
indoors.
[0084] The weak GPS signal test 305 evaluates the strengths of the
signals it is receiving from the various satellites, paying
particular attention to the satellites that are nearest to zenith.
If the signal strength falls below a predetermined threshold, the
weak GPS signal test 305 provides an indication that the digital
camera 10 (FIG. 1) is indoors 220. Likewise, if the signal strength
is above a predetermined threshold, it can be concluded that the
digital camera 10 is probably outdoors.
[0085] In some embodiments, the analyze GPS signal step 210 uses
only the weak GPS signal test 305 to determine whether the digital
camera 10 is outdoors or indoors. However, the weak GPS signal test
305 does not always provide a reliable determination that the
digital camera 10 is outdoors. For example, if the digital camera
10 is indoors but near a window, or other UHF transmissive
material, the GPS sensor 25 (FIG. 1) can still receive a GPS signal
205 in some cases. Therefore, in some embodiments of the present
invention, it can be useful to supplement the weak GPS signal test
305 with additional optional indications of whether the digital
camera 10 is in an indoor or outdoor environment.
[0086] In some embodiments, a geographical database 315 can be used
by the analyze GPS signal step 210 to provide additional
indications of whether the digital camera is outdoors 215 or
indoors 220. The geographical database 315 can include a building
database 325 that provides an indication of land usage as a
function of longitude and latitude, indicating the locations of
known buildings and known open spaces.
[0087] An optional within known building test 310 can compare a
geographic location 302 (longitude and latitude) determined from
the GPS signal 205 to the building database 325 to determine
whether the geographic location 302 corresponds to the location of
a known building. If so, the within known building test 310
provides an indication that the digital camera 10 is indoors
220.
[0088] Satellite imagery showing land usage is widely available
today. Such imagery can be manually or automatically analyzed to
populate the building database 325 which can be stored in a memory
system accessible to the digital camera 10 (e.g., in a memory in
the digital camera 10, or in a location that can be accessed using
a wireless communication network). In some embodiments, the user
can be enabled to update the building database 325 to include
building locations that are not included in the provided building
database 325, or can be provided with tools to define his/her own
building database 325 corresponding to locations where the user
frequently captures photographs.
[0089] An optional inconsistent altitude test 320 can be used to
provide an additional indication of whether the digital camera 10
is outdoors 215 or indoors 220. The geographical location 302
determined by analyzing the GPS signal 205 includes not only
longitude and latitude values, but also an elevation value relative
to sea level. The geographical database 315 can include a topology
database 330 that provides an indication of ground elevation as a
function of longitude and latitude. The inconsistent altitude test
320 compares the known ground elevation at the current longitude
and latitude determined from the topology database 330 to the
elevation value for the geographical location 302. If it is found
that the elevation value for the geographical location 302 is
substantially higher than the known ground elevation at that
location, then it can be concluded that the digital camera is
probably being used on an upper floor of a building. In this case,
the inconsistent altitude test 320 provides an indication that the
digital camera 10 is indoors 220, otherwise it provides an
indication that the digital camera 10 is outdoors 215.
[0090] In some embodiments, the analyze GPS signal step 210 can
include all three of the tests shown in FIG. 4 (the weak GPS signal
test 305, the within known building test 310 and the inconsistent
altitude test 320). In other embodiments, only a subset of these
tests can be used. In some embodiments, the various tests can be
executed in a sequential manner as shown in the example of FIG. 4.
In other embodiments, a plurality of tests can be run in parallel
and the results can be combined using a model which weights the
individual test results in a probabilistic manner. For example, a
probability value that the digital camera is indoors can be
determined as a function of a determined signal strength value and
a determined elevation above ground level value:
P.sub.indoors=f(S,Z.sub.G) (5)
where Pindoors is the probability that the digital camera 10 is
indoors, S is the determined signal strength value, ZG is the
determined elevation above ground level value, and f(.cndot.) is a
probability function that can be determined by fitting
experimentally determined data using methods well known in the art.
If the probability that the digital camera 10 is indoors is
determined to be more than 50%, then the analyze GPS signal step
210 can provide an indication the digital camera 10 is indoors 220.
Otherwise, it can provide an indication the digital camera 10 is
outdoors 215.
[0091] Those skilled in the art will recognize that the GPS signal
205 can be analyzed in other manners to provide an indication of
whether the digital camera 10 is outdoors 215 or indoors 220. For
example, rather than analyzing the GPS signal strength 300 itself,
the analyze GPS signal test 210 can monitor the GPS signal strength
300 over time and can provide an indication that the digital camera
10 has moved to an indoors location when a substantial drop in the
GPS signal strength 300 is detected.
[0092] In general, when it is determined that the digital camera 10
is outdoors 215, the digital camera 10 can be operated in a default
outdoor photography mode. Such a mode would include a default
exposure determination process and a default image processing
chain, including default white balance and color correction
operations that are designed for a typical daylight illumination.
In some embodiments of the present invention, the determine outdoor
camera settings step 225 simply sets the digital camera 10 to
operate in the default outdoor photography mode.
[0093] While the default outdoor photography mode will produce good
results in most outdoor environments, there are certain photography
situations where other alternate outdoor photography modes are
known to produce superior results. For example, when photographing
sunsets and sunrises, it can be preferable to adjust the exposure
and color processing to provide images having enhanced
colorfulness. FIG. 5 shows a flow chart illustrating more details
of the determine outdoor camera settings step 225 according to one
embodiment of the present invention which selects a sunset
photography mode when it is determined that the digital camera 10
is capturing an image in a likely sunrise or sunset
environment.
[0094] A sunrise/sunset test 400 is used to analyze a date/time and
geographic location 405 determined from the GPS signal 205 to
determine whether the image capture environment is likely to
correspond to sunrise or sunset conditions. Given a geographical
location, together with the date, well-known methods can be used to
determine corresponding sunrise and sunset times.
[0095] In one embodiment, the sunrise/sunset test 400 computes the
sunrise and sunset times corresponding to the date and geographic
location determined as part of the date/time and geographic
location 405. The determined sunrise and sunset times are then
compared to the time from the determined date/time and geographic
location 405. If the time falls within a specified time interval
around the sunrise and sunset times, then a set sunset mode step
415 is executed to select appropriate camera settings 185.
[0096] The set sunset mode step 415 selects camera settings 185
appropriate to set the digital camera to operate in a sunset mode
which is designed to produce pleasing sunrise and sunset
photographs. The sunset mode has associated exposure settings,
white balance settings and color correction settings that are
appropriate for sunset photography. For example, the sunset mode
can introduce an exposure shift to reduce the exposure level by a
defined increment in order to avoid washing out the sunset colors.
Similarly, the sunset mode can use white balance settings that
override any automatic white balance settings that might tend to
remove the reddish tint, and can use color correction settings that
can boost the image colorfulness in order to enhance the sunset
colors.
[0097] If the sunrise/sunset test 400 determines that the digital
camera 10 is not being operated at sunrise or sunset, a night test
420 is used to determine whether the digital camera is being
operated at night. If so, a set night mode step 425 is executed to
select the camera settings 185, otherwise a set normal outdoor mode
step 410 is executed to select the camera settings 185.
[0098] The set night mode step 425 selects camera settings 185
appropriate for night photography. Daylight can be ruled out as a
possible illuminant for night photography; rather it can be assumed
that the scene illumination will be provided by the flash 2, or by
some other artificial illumination. The set night mode step 425 can
be used to set the digital camera to a mode where the flash 2 will
automatically be fired (unless a level of ambient illumination is
detected). The set night mode step 425 can also be used to select
color correction settings that are appropriate for the flash 2 (or
for other artificial illuminants). In the night mode, it can also
be desirable to reduce the overall exposure level to maintain the
impression of the image being captured at night and to avoid
overexposure problems that are commonly observed for night flash
photographs.
[0099] The set normal outdoor mode step 410 selects camera settings
185 appropriate to set the digital camera to operate in the default
outdoor photography mode. The camera settings 185 would include
settings such as exposure settings, white balance settings and
color correction settings.
[0100] In some embodiments of the present invention, the determine
indoor camera settings step 235 (FIG. 3) simply sets the digital
camera 10 to operate in a default indoor photography mode. While
the default indoor photography mode will produce good results in
most indoor environments, there are certain photography situations
where it can be appropriate to use other alternate indoor
photography modes.
[0101] FIG. 6 shows a flow chart illustrating more details of the
determine indoor camera settings step 235 according to one
embodiment of the present invention which selects between various
indoor photography modes responsive to the GPS signal 205. A flash
photography prohibited test 500 is used to determine whether the
date/time and geographic location 405 determined from the GPS
signal 205 corresponds to a geographic location where flash
photography is known to be prohibited. If the geographic location
corresponds to a location such as a theater, a museum or a public
building where flash photography is prohibited, then the set flash
off step 510 is executed to set the digital camera 10 to a no flash
mode.
[0102] The flash photography prohibited test 500 determines whether
flash photography is prohibited at a particular location by
comparing the geographic location to a predefined flash prohibited
database 505 specifying known flash prohibited zones. In some
cases, flash photography may only be prohibited at certain times of
the day. In this case, the flash prohibited database 505 can store
both the locations of flash prohibited zones, together with
corresponding time intervals. The flash photography prohibited step
500 can take into account both the time and the geographic
location.
[0103] If the digital camera 10 is not determined to be in a flash
prohibited zone, a fire flash test 530 is used to determine whether
or not the flash 2 (FIG. 1) should be fired. The fire flash test
530 can use automatic algorithms well-known in the art to determine
whether or not it is appropriate to use the flash 2 given the
photography environment. For example, the flash 2 does not need to
be fired if the scene illumination level is above a certain level.
If the fire flash test 530 determines that the flash should not be
fired, the process proceeds to the set flash off step 510,
otherwise a set flash on step 535 is executed. The set flash on
step 535 sets the digital camera 10 to capture images using the
flash 2.
[0104] A building illuminant known test 540 is used to determine
whether the digital camera 10 is located in a building with a known
building illuminant. In some embodiments, the building illuminant
known test 540 determines whether the building illuminant is known
by comparing the geographic location to a predefined building
illuminant database 550 specifying known building illuminant types
as a function of geographic location. For example, certain public
buildings may be known to use fluorescent illumination. The
building illuminant database 550 can be determined by compiling a
database for public locations where photographs are commonly
captured.
[0105] In other embodiments, rather than storing the illuminant
type, the building illuminant database 550 can store an indication
of the building type as a function of geographic location. If the
building type at a particular location is an office building, then
it can be assumed that the illuminant type is probably office
fluorescent. On the other hand, if the building type at a
particular location is a home, then it can be assumed that the
illuminant type is tungsten, or if the particular location is a
sports arena, then it can be assumed that the illumination type
corresponds to a metal vapor illuminant. The building illuminant
known test 540 can also take into account the time of day. If the
image is being captured in a home during the day, then it can be
assumed that the illuminant will be a mixture of the interior
illuminant with daylight coming through any windows.
[0106] If the building illuminant known test 540 determines a known
illuminant, then a set mixed color correction step 545 can be used
to choose color correction settings appropriate for a mixed
illumination environment. In some embodiments, different color
correction settings can be chosen depending on the identity of the
determined illuminant. For example, one color correction setting
can be used for mixed flash/fluorescent illumination, and a
different color correction setting can be used for mixed
flash/tungsten illumination. The different color correction
settings can, for example, include different white balance settings
and different color correction matrices that are optimized for the
illumination conditions.
[0107] Otherwise, if the building illuminant known test 540 can not
determine a known illuminant corresponding to the geographical
location, a set auto color correction step 525 can be used to set
the camera to an auto color correction mode which uses default
indoor camera settings.
[0108] For the case where the flash is not used, an analogous
building illuminant known test 515 can be applied to determine
whether the digital camera 10 is located in a building with a known
building illuminant. If not, then the set auto color correction
step 525 is called as before. If a known illuminant is determined,
then a set illuminant color correction step 520 is used to choose
color correction settings appropriate for the determined known
illuminant. For example, color correction settings optimized for
fluorescent illumination can be selected if the geographic location
is found to correspond to an office building known to use
fluorescent illumination.
[0109] If the GPS signal 205 is too weak to determine the
geographic location due to the fact that the digital camera 10 is
indoors 220, then the flash photography prohibited test 500 and the
building illuminant known tests 515 and 540 can use the last known
geographic location to compare with the flash prohibited database
505 and the building illuminant database 550.
[0110] One skilled in the art will recognize that there are a wide
variety of other ways that the camera settings 185 can be
determined responsive to whether the digital camera 10 is outdoors
215 or indoors 220 in accordance with the present invention.
[0111] In some embodiments of the present invention the GPS signal
205 can be monitored over time to determine whether the digital
camera 10 is moving. If it is detected that the digital camera is
moving (e.g, if the photographer is walking or is in a moving
vehicle), then various camera settings 185 can be adjusted
accordingly. For example, a shorter exposure time can be used to
reduce blur, or an image stabilization mode can be turned on.
[0112] The invention has been described in detail with particular
reference to certain preferred embodiments thereof, but it will be
understood that variations and modifications can be effected within
the spirit and scope of the invention.
PARTS LIST
[0113] 2 flash [0114] 4 lens [0115] 6 adjustable aperture and
adjustable shutter [0116] 8 zoom and focus motor drives [0117] 10
digital camera [0118] 12 timing generator [0119] 14 image sensor
[0120] 16 ASP and A/D Converter [0121] 18 buffer memory [0122] 20
processor [0123] 22 audio codec [0124] 24 microphone [0125] 25 GPS
sensor [0126] 26 speaker [0127] 28 firmware memory [0128] 30 image
memory [0129] 32 image display [0130] 34 user controls [0131] 36
display memory [0132] 38 wired interface [0133] 40 computer [0134]
44 video interface [0135] 46 video display [0136] 48
interface/recharger [0137] 50 wireless modem [0138] 52 radio
frequency band [0139] 58 wireless network [0140] 70 Internet [0141]
72 photo service provider [0142] 90 white balance setting [0143] 95
white balance step [0144] 100 color sensor data [0145] 105 noise
reduction step [0146] 110 ISO setting [0147] 115 demosaicing step
[0148] 120 resolution mode setting [0149] 125 color correction step
[0150] 130 color mode setting [0151] 135 tone scale correction step
[0152] 140 contrast setting [0153] 145 image sharpening step [0154]
150 sharpening setting [0155] 155 image compression step [0156] 160
compression mode setting [0157] 165 file formatting step [0158] 170
metadata [0159] 175 user settings [0160] 180 digital image file
[0161] 185 camera settings [0162] 200 sense GPS signal step [0163]
205 GPS signal [0164] 210 analyze GPS signal step [0165] 215
outdoors [0166] 220 indoors [0167] 225 determine outdoor camera
settings step [0168] 235 determine indoor camera settings step
[0169] 240 capture digital image step [0170] 245 input digital
image [0171] 250 process digital image step [0172] 255 processed
digital image [0173] 260 store digital image step [0174] 300 GPS
signal strength [0175] 302 geographical location [0176] 305 weak
GPS signal test [0177] 310 within known building test [0178] 315
geographical database [0179] 320 inconsistent altitude test [0180]
325 building database [0181] 330 topology database [0182] 400
sunrise/sunset test [0183] 405 date/time and geographic location
[0184] 410 set normal outdoor mode step [0185] 415 set sunset mode
step [0186] 420 night test [0187] 425 set night mode step [0188]
500 flash photography prohibited test [0189] 505 flash prohibited
database [0190] 510 set flash off step [0191] 515 building
illuminant known test [0192] 520 set illuminant color correction
step [0193] 525 set auto color correction step [0194] 530 fire
flash test [0195] 535 set flash on step [0196] 540 building
illuminant known test [0197] 545 set mixed color correction step
[0198] 550 building illuminant database
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