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Camera Device Property Constants

Windows Image Acquisition (WIA) hardware devices have property values that are stored in the Windows registry. For more information, see Common Device Property Constants.

The following device property constants, with their associated strings, are specific to digital cameras. The prefix "WIA_DPC_" indicates a Device Property for Cameras and is the naming convention used in C/C++. For scripting purposes these constants use the prefix "CameraDevice" and are part of the WiaItemPropertyId enumerated type. The corresponding member name from that script enumeration appears in parentheses next to the C/C++ constant name in the following list.

Note

WIA does not support cameras in Windows Vista or later. For those versions of the Windows, use the Windows Portable Device (WPD) API described in the Windows Driver Development Kit (DDK) to acquire images from cameras.

 

Constant/value Description
WIA_DPC_PICTURES_TAKEN
CameraDevicePicturesTaken
The number of pictures that the camera has taken. The minidriver creates and maintains this property.
Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE
WIA_DPC_PICTURES_REMAINING
CameraDevicePicturesRemaining
The number of pictures that can be taken, given the current property settings. If these settings change, and the changes affect the size of the images that the camera device produces, the WIA minidriver should update the number of remaining pictures. The minidriver creates and maintains this property.
Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE
WIA_DPC_EXPOSURE_MODE
CameraDeviceExposureMode
Indicates the camera's current exposure mode. An application changes this property to control the exposure mode of the camera device.
Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST
The following table has the seven constants that are valid with this property.
Exposure Mode Description
EXPOSUREMODE_MANUAL The shutter speed and aperture are set by the user.
EXPOSUREMODE_AUTO The shutter speed and aperture are automatically set by the camera.
EXPOSUREMODE_APERTURE_PRIORITY The aperture is set by the user, and the camera automatically sets the shutter speed.
EXPOSUREMODE_SHUTTER_PRIORITY The shutter speed is set by the user, and the camera automatically sets the aperture.
EXPOSUREMODE_PROGRAM_CREATIVE The shutter speed and aperture are automatically set by the camera, optimized for still subject matter.
EXPOSUREMODE_PROGRAM_ACTION The shutter speed and aperture are automatically set by the camera, optimized for scenes containing fast motion.
EXPOSUREMODE_PORTRAIT The shutter speed and aperture are automatically set by the camera, optimized for portrait photography.

 

WIA_DPC_EXPOSURE_COMP
CameraDeviceExposureComp

Allows for the adjustment of the set point of the digital camera's auto-exposure control. For example, a setting of zero does not change the factory-set auto-exposure level. The units are in "stops" that are scaled by a factor of 1000, to allow for fractional stop values. A setting of 2000 corresponds to two stops more exposure (four times more energy on the sensor), yielding brighter images. A setting of -1000 corresponds to one stop less exposure (one-half the energy on the sensor) yielding darker images. The setting values are in Additive System of Photographic Exposure (APEX) units. This property may be expressed as either a list or a range of values. This property is typically used only when the device has the WIA_DPC_EXPOSURE_MODE property set to EXPOSUREMODE_MANUAL.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_RANGE or WIA_PROP_LIST

WIA_DPC_EXPOSURE_TIME
CameraDeviceExposureTime

Corresponds to the shutter speed, in seconds that are scaled by 10,000. Typically, the device uses this property only when the WIA_DPC_EXPOSURE_MODE property is set to EXPOSUREMODE_MANUAL or EXPOSUREMODE_SHUTTER_PRIORITY.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_RANGE or WIA_PROP_LIST

WIA_DPC_FNUMBER
CameraDeviceFNumber

Corresponds to the aperture of the lens, in units of the f-stop number scaled by 100. The setting of this property is typically valid only when the WIA_DPC_EXPOSURE_MODE property is set to EXPOSUREMODE_MANUAL or EXPOSUREMODE_APERTURE_PRIORITY.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

WIA_DPC_FLASH_MODE
CameraDeviceFlashMode

Defines the current flash mode setting for the camera device. The device driver enumerates the supported values of this property. An application writes this property to set the flash mode for the camera device.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following table has the six constants that are valid with this property.

Flash Mode Definition
FLASHMODE_AUTO The camera device determines the proper flash settings.
FLASHMODE_FILL The camera device is configured to flash regardless of current lighting conditions.
FLASHMODE_OFF The camera device is configured not to flash for any picture taken.
FLASHMODE_REDEYE_AUTO The camera device determines the proper flash settings using red-eye reduction, regardless of current lighting conditions.
FLASHMODE_REDEYE_FILL The camera device is configured to use red-eye reduction and flash regardless of current lighting conditions.
FLASHMODE_EXTERNALSYNC The camera device is configured to synchronize with external flash units.

 

WIA_DPC_FOCUS_MODE
CameraDeviceFocusMode

Defines the current focus mode setting for the camera device. The device driver enumerates the supported values of this property. An application writes this property to set the focus mode for the camera device.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following table has the three constants that are valid with this property.

Focus Mode Description
FOCUSMODE_MANUAL The camera device is configured to allow the user to focus manually.
FOCUSMODE_AUTO The camera device is configured to focus automatically.
FOCUSMODE_MACROAUTO The camera device is configured to focus automatically using short-range macro settings.

 

WIA_DPC_FOCUS_MANUAL_DIST

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_ZOOM_POSITION

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_PAN_POSITION
CameraDevicePanPosition

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_TILT_POSITION
CameraDeviceTiltPosition

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_TIMER_MODE
CameraDeviceTimerMode

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_TIMER_VALUE
CameraDeviceTimerValue

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_POWER_MODE
CameraDevicePowerMode

Defines the current power source for the camera device. An application reads this property to determine what power source the camera is using.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

The following table has the two constants that are valid with this property.

Power Mode Description
POWERMODE_LINE The camera device is operating on a power adapter.
POWERMODE_BATTERY The camera device is operating on battery power.

 

WIA_DPC_BATTERY_STATUS
CameraDeviceBatteryStatus

The percentage of battery power that is left to operate the camera device. This value should be an integer from 0 through 100. An application reads this property to determine the remaining battery life of the camera device.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_THUMB_WIDTH
CameraDeviceThumbWidth

The width, in pixels, of a thumbnail image to use for newly captured images. An application reads this value to get an estimated size for displaying thumbnails in its user interface.

Type: VT_I4, Access: Read/Write (WIA_PROP_LIST) or Read Only (WIA_PROP_NONE), Valid values: WIA_PROP_LIST or WIA_PROP_NONE

WIA_DPC_THUMB_HEIGHT
CameraDeviceThumbHeight

The width, in pixels, of a thumbnail image to use for newly captured images. An application reads this value to get an estimated size for displaying thumbnails in its user interface.

Type: VT_I4, Access: Read/Write (WIA_PROP_LIST) or Read Only (WIA_PROP_NONE), Valid values: WIA_PROP_LIST or WIA_PROP_NONE

WIA_DPC_PICT_WIDTH
CameraDevicePictWidth

The width in pixels to use for newly captured images. The list of valid values for this property has a one-to-one correspondence to the list of valid values for the WIA_DPC_PICT_HEIGHT property. If the individual width and height are linearly settable and orthogonal to each other, they may be expressed as a range.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_PICT_HEIGHT
CameraDevicePictHeight

The height in pixels to use for newly captured images. The list of valid values for this property has a one-to-one correspondence with the list of valid values for the WIA_DPC_PICT_WIDTH property. If the individual width and height are linearly settable and orthogonal to each other, they may be expressed as a range.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_DIMENSION

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_COMPRESSION_SETTING
CameraDeviceCompressionSetting

Intended to be approximately linear with respect to perceived image quality over a broad range of scene content, and it contains either a range or a list of integers. Smaller integers are used to represent lower quality (that is, maximum compression), whereas larger integers are used to represent higher quality (that is, minimum compression). Any available settings on a device are relative only to that device and are therefore device specific.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_FOCUS_METERING

Reserved, do not use.

Type: VT_I4, Access: Read Only, Valid values: WIA_PROP_NONE

WIA_DPC_TIMELAPSE_INTERVAL
CameraDeviceTimelapseInterval

The time, in milliseconds, between image captures in a time-lapse capture operation.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_NONE, WIA_PROP_LIST, or WIA_PROP_RANGE

WIA_DPC_TIMELAPSE_NUMBER
CameraDeviceTimelapseNumber

The number of images the device attempts to capture during a time-lapse capture.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_NONE, WIA_PROP_LIST, or WIA_PROP_RANGE

WIA_DPC_BURST_INTERVAL
CameraDeviceBurstInterval

The time, in milliseconds, between image captures during a burst operation.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_NONE, WIA_PROP_LIST, or WIA_PROP_RANGE

WIA_DPC_BURST_NUMBER
CameraDeviceBurstNumber

The number of images the device attempts to capture during a burst operation.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_NONE, WIA_PROP_LIST, or WIA_PROP_RANGE

WIA_DPC_EFFECT_MODE
CameraDeviceEffectMode

Specifies the special image acquisition mode of the camera.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following table has the three constants that are valid with this property.

Effect Mode Description
EFFECTMODE_STANDARD Capture an image in the standard mode for the camera.
EFFECTMODE_BW Capture a grayscale image.
EFFECTMODE_SEPIA Capture a sepia image.

 

WIA_DPC_DIGITAL_ZOOM
CameraDeviceDigitalZoom

The effective zoom ratio of the digital camera's acquired image, scaled by a factor of 10. A value of 10 corresponds to the absence of digital zoom (1X), which is the standard scene size captured by the camera. A value of 20 corresponds to a 2X zoom, where one-quarter of the standard scene size is captured by the camera.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_SHARPNESS
CameraDeviceSharpness

The perceived sharpness of a captured image. This property can use either a list of values or a range of values. The minimum value represents the least amount of sharpness, whereas the maximum value represents the maximum sharpness. Typically a value in the middle of the range represents normal, or default, sharpness.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_CONTRAST
CameraDeviceContrast

The perceived contrast of a captured image. This property can contain either a list of values or a range of values. The minimum supported value represents the least amount of contrast, whereas the maximum value represents the most contrast. Typically, a value in the middle of the range represents normal, or default, contrast.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_CAPTURE_MODE
CameraDeviceCaptureMode

Sets the image capture mode.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following table has the three constants that are valid with this property.

Capture Mode Description
CAPTUREMODE_NORMAL Normal mode for the camera.
CAPTUREMODE_BURST Capture more than one image in quick succession as defined by the values of the WIA_DPC_BURST_NUMBER and WIA_DPC_BURST_INTERVAL properties.
CAPTUREMODE_TIMELAPSE Capture more than one image in succession as defined by the WIA_DPC_TIMELAPSE_NUMBER and WIA_DPC_TIMELAPSE_INTERVAL properties.

 

WIA_DPC_CAPTURE_DELAY
CameraDeviceCaptureDelay

The value representing the amount of time delay, in milliseconds, that should be inserted between the capture trigger and the actual initiation of the data capture. This property is not intended to be used to describe the time between frames for single-initiation, multiple captures such as burst or time lapse, which have separate interval properties WIA_DPC_BURST_INTERVAL and WIA_DPC_TIMELAPSE_INTERVAL. In those cases, it still serves as an initial delay before the first image in the series is captured, independent of the time between frames. For no precapture delay, this property should be set to zero.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_EXPOSURE_INDEX
CameraDeviceExposureIndex

Allows for the emulation of film speed settings on a digital camera. The settings correspond to the ISO designations (ASA/DIN). Typically, a device supports discrete enumerated values, but continuous control over a range of values is possible. A value of 0xFFFF corresponds to the Automatic ISO setting.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_EXPOSURE_METERING_MODE
CameraDeviceExposureMeteringMode

Specifies the mode the camera uses to automatically adjust the exposure setting.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

Exposure Metering Mode Description
EXPOSUREMETERING_AVERAGE Set the exposure based on an average of the entire scene.
EXPOSUREMETERING_CENTERWEIGHT Set the exposure based on a center-weighted average.
EXPOSUREMETERING_MULTISPOT Set the exposure based on a multispot pattern.
EXPOSUREMETERING_CENTERSPOT Set the exposure based on a center spot.

 

WIA_DPC_FOCUS_METERING_MODE
CameraDeviceFocusMeteringMode

Specifies the mode the camera uses to automatically adjust the focus.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following table has the two constants that are valid with this property.

Focus Metering Mode Description
FOCUSMETERING_CENTERSPOT Adjust the focus based on a center spot.
FOCUSMETERING_MULTISPOT Adjust the focus based on a multispot pattern.

 

WIA_DPC_FOCUS_DISTANCE
CameraDeviceFocusDistance

The distance, in millimeters, between the image-capturing plane of the digital camera and the point of focus. A value of 0xFFFF corresponds to a setting greater than 655 meters.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST or WIA_PROP_RANGE

WIA_DPC_FOCAL_LENGTH
CameraDeviceFocalLength

The 35mm-equivalent focal length. The values of this property correspond to the focal length in millimeters multiplied by 100. The focal length determines the optical zoom.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_NONE

WIA_DPC_RGB_GAIN
CameraDeviceRGBGain

A null-terminated Unicode string that represents the red, green, and blue gain applied to image data, respectively. For example, "4:25:50" represents a red gain of 4, a green gain of 25, and a blue gain of 50.

Type: VT_BSTR, Access: Read/Write, Valid values: WIA_PROP_NONE

WIA_DPC_WHITE_BALANCE
CameraDeviceWhiteBalance

Specifies how the digital camera weights color channels.

Type: VT_I4, Access: Read/Write, Valid values: WIA_PROP_LIST

The following is a list of possible values for this property.

White Balance Description
WHITEBALANCE_MANUAL The white balance is set directly using the WIA_DPC_RGB_GAIN property.
WHITEBALANCE_AUTO The camera uses an automatic mechanism to set the white balance.
WHITEBALANCE_ONEPUSH_AUTO The camera determines the white balance setting when a user presses the capture button while pointing the camera at a white surface.
WHITEBALANCE_DAYLIGHT The camera sets the white balance to a value appropriate for use in daylight conditions.
WHITEBALANCE_FLORESCENT The camera sets the white balance to a value appropriate for use with a fluorescent light source.
WHITEBALANCE_TUNGSTEN The camera sets the white balance to a value appropriate for use with a tungsten light source.
WHITEBALANCE_FLASH The camera sets the white balance to a value appropriate for use with an electronic flash.

 

WIA_DPC_UPLOAD_URL
CameraDeviceUploadURL

Describes a URL. The URL described by this proroperty is one that images or objects, after they are acquired from the device, can be uploaded to—according to one of the following scenarios.

  • A WIA application reads this property and allows the user to automatically upload images to the URL.
  • An application sets the URL, and other devices (kiosks and so forth) use this property.

Microsoft Windows does not upload images by itself.

Type: VT_BSTR, Access: Read/Write, Valid values: WIA_PROP_NONE

WIA_DPC_ARTIST
CameraDeviceArtist

The name of the owner ( which is the current user) of the device. The device uses this property to populate the Artist field in every EXIF image that it captures.

Type: VT_BSTR, Access: Read/Write, Valid values: WIA_PROP_NONE

WIA_DPC_COPYRIGHT_INFO
CameraDeviceCopyrightInfo

The copyright notification. The device uses this property to populate the Copyright field in every EXIF image that it captures.

Type: VT_BSTR, Access: Read/Write, Valid values: WIA_PROP_NONE

Requirements

Requirement Value
Minimum supported client
Windows 2000 Professional, Windows XP [desktop apps only]
Minimum supported server
Windows Server 2003 [desktop apps only]
Header
Wiadef.h