ImageCapture
open class ImageCapture : UseCase
| kotlin.Any | ||
| ↳ | androidx.camera.core.UseCase | |
| ↳ | androidx.camera.core.ImageCapture | |
A use case for taking a picture.
This class is designed for basic picture taking. It provides takePicture() functions to take a picture to memory or save to a file, and provides image metadata. Pictures are taken in automatic mode after focus has converged. The flash mode can additionally be set by the application.
TakePicture returns immediately and a listener is called to provide the results after the capture completes. Multiple calls to takePicture will take pictures sequentially starting after the previous picture is captured.
Note that focus and exposure metering regions can be controlled via Preview.
When capturing to memory, the captured image is made available through an ImageProxy via an ImageCapture.OnImageCapturedListener.
Summary
Public constructors |
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<init>(userConfig: ImageCaptureConfig!)Creates a new image capture use case from the given configuration. |
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Public methods |
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| open FlashMode! |
Get the flash mode. |
| open Unit |
setFlashMode(flashMode: FlashMode!)Set the flash mode. |
| open Unit |
setTargetAspectRatio(aspectRatio: Rational!)Sets target aspect ratio. |
| open Unit |
setTargetRotation(rotation: Int)Sets the desired rotation of the output image. |
| open Unit |
takePicture(listener: ImageCapture.OnImageCapturedListener!)Captures a new still image for in memory access. |
| open Unit |
takePicture(saveLocation: File!, imageSavedListener: ImageCapture.OnImageSavedListener!)Captures a new still image and saves to a file. |
| open Unit |
takePicture(saveLocation: File!, imageSavedListener: ImageCapture.OnImageSavedListener!, metadata: ImageCapture.Metadata!)Captures a new still image and saves to a file along with application specified metadata. |
| open String |
toString() |
Protected methods |
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| open Unit |
onCameraControlReady(cameraId: String!)Configures flash mode to CameraControlInternal once it is ready. |
Inherited functions |
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Public constructors
<init>
ImageCapture(userConfig: ImageCaptureConfig!)
Creates a new image capture use case from the given configuration.
| Parameters | |
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userConfig |
ImageCaptureConfig!: for this use case instance |
| Exceptions | |
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IllegalArgumentException |
if the configuration is invalid. |
Public methods
getFlashMode
open fun getFlashMode(): FlashMode!
Get the flash mode.
| Return | |
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FlashMode!: the FlashMode. |
setFlashMode
open fun setFlashMode(flashMode: FlashMode!): Unit
Set the flash mode.
| Parameters | |
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flashMode |
FlashMode!: the FlashMode. |
setTargetAspectRatio
open fun setTargetAspectRatio(aspectRatio: Rational!): Unit
Sets target aspect ratio.
This sets the cropping rectangle returned by ImageProxy#getCropRect() returned from ImageCapture#takePicture(OnImageCapturedListener).
This crops the saved image when calling ImageCapture#takePicture(File, OnImageSavedListener) or ImageCapture#takePicture(File, OnImageSavedListener, Metadata).
Cropping occurs around the center of the image and as though it were in the target rotation.
| Parameters | |
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aspectRatio |
Rational!: New target aspect ratio. |
setTargetRotation
open fun setTargetRotation(rotation: Int): Unit
Sets the desired rotation of the output image.
This will affect the EXIF rotation metadata in images saved by takePicture calls and the rotation value returned by OnImageCapturedListener.
In most cases this should be set to the current rotation returned by . In that case, the output rotation from takePicture calls will be the rotation, which if applied to the output image, will make it match the display orientation.
While rotation can also be set via ImageCaptureConfig.Builder#setTargetRotation(int), using ImageCapture#setTargetRotation(int) allows the target rotation to be set dynamically. This can be useful if an app locks itself to portrait, and uses the orientation sensor to set rotation to take landscape images when the device is rotated.
If no target rotation is set by the application, it is set to the value of Display#getRotation() of the default display at the time the use case is created.
| Parameters | |
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rotation |
Int: Target rotation of the output image, expressed as one of Surface#ROTATION_0, Surface#ROTATION_90, Surface#ROTATION_180, or Surface#ROTATION_270. |
takePicture
open fun takePicture(listener: ImageCapture.OnImageCapturedListener!): Unit
Captures a new still image for in memory access.
The listener's callback will be called only once for every invocation of this method. The listener is responsible for calling Image#close() on the returned image.
| Parameters | |
|---|---|
listener |
ImageCapture.OnImageCapturedListener!: Listener to be called for the newly captured image |
takePicture
open fun takePicture(saveLocation: File!, imageSavedListener: ImageCapture.OnImageSavedListener!): Unit
Captures a new still image and saves to a file.
The listener's callback will be called only once for every invocation of this method.
| Parameters | |
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saveLocation |
File!: Location to store the newly captured image. |
imageSavedListener |
File!: Listener to be called for the newly captured image. |
takePicture
open fun takePicture(saveLocation: File!, imageSavedListener: ImageCapture.OnImageSavedListener!, metadata: ImageCapture.Metadata!): Unit
Captures a new still image and saves to a file along with application specified metadata.
The listener's callback will be called only once for every invocation of this method.
This function accepts metadata as a parameter from application code. For JPEGs, this metadata will be included in the EXIF.
| Parameters | |
|---|---|
saveLocation |
File!: Location to store the newly captured image. |
imageSavedListener |
File!: Listener to be called for the newly captured image. |
metadata |
File!: Metadata to be stored with the saved image. For JPEG this will be included in the EXIF. |
toString
open fun toString(): String