public
abstract
class
CameraConstrainedHighSpeedCaptureSession
extends CameraCaptureSession
| java.lang.Object | ||
| ↳ | android.hardware.camera2.CameraCaptureSession | |
| ↳ | android.hardware.camera2.CameraConstrainedHighSpeedCaptureSession | |
A constrained high speed capture session for a CameraDevice, used for capturing high
speed images from the CameraDevice for high speed video recording use case.
A CameraHighSpeedCaptureSession is created by providing a set of target output surfaces to
createConstrainedHighSpeedCaptureSession(List, Once created, the session is
active until a new session is created by the camera device, or the camera device is closed.
An active high speed capture session is a specialized capture session that is only targeted at
high speed video recording (>=120fps) use case if the camera device supports high speed video
capability (i.e., REQUEST_AVAILABLE_CAPABILITIES contains
REQUEST_AVAILABLE_CAPABILITIES_CONSTRAINED_HIGH_SPEED_VIDEO). It only
accepts request lists created via createHighSpeedRequestList(CaptureRequest), and the request list can
only be submitted to this session via captureBurst, or
setRepeatingBurst. See
createConstrainedHighSpeedCaptureSession(List for more details of the
limitations.
Creating a session is an expensive operation and can take several hundred milliseconds, since it
requires configuring the camera device's internal pipelines and allocating memory buffers for
sending images to the desired targets. Therefore the setup is done asynchronously, and
createConstrainedHighSpeedCaptureSession(List will send the ready-to-use
CameraCaptureSession to the provided listener's
onConfigured(CameraCaptureSession) callback. If configuration cannot be
completed, then the onConfigureFailed(CameraCaptureSession) is called, and
the session will not become active.
If a new session is created by the camera device, then the previous session is closed, and its
associated onClosed callback will be
invoked. All of the session methods will throw an IllegalStateException if called once the
session is closed.
A closed session clears any repeating requests (as if stopRepeating() had been called),
but will still complete all of its in-progress capture requests as normal, before a newly created
session takes over and reconfigures the camera device.
Public constructors | |
|---|---|
CameraConstrainedHighSpeedCaptureSession()
|
|
Public methods | |
|---|---|
abstract
List<CaptureRequest>
|
createHighSpeedRequestList(CaptureRequest request)
Create a unmodifiable list of requests that is suitable for constrained high speed capture session streaming. |
Inherited methods | |
|---|---|
 From
class
android.hardware.camera2.CameraCaptureSession
| |
From
class
java.lang.Object
| |
From
interface
java.lang.AutoCloseable
| |
CameraConstrainedHighSpeedCaptureSession ()
List<CaptureRequest> createHighSpeedRequestList (CaptureRequest request)
Create a unmodifiable list of requests that is suitable for constrained high speed capture session streaming.
High speed video streaming creates significant performance pressure on the camera device,
so to achieve efficient high speed streaming, the camera device may have to aggregate
multiple frames together. This means requests must be sent in batched groups, with all
requests sharing the same settings. This method takes the list of output target
Surfaces (subject to the output Surface requirements specified by the constrained high speed
session) and a request, and generates a request list that has the same
controls for each request. The input request must contain the target
output Surfaces and target high speed FPS range that is one of the
getHighSpeedVideoFpsRangesFor(Size) for the Surface size.
If both preview and recording Surfaces are specified in the request, the
target FPS range in the input
request must be a fixed frame rate FPS range, where the
minimal FPS ==
maximum FPS. The created request list will contain
a interleaved request pattern such that the preview output FPS is at least 30fps, the
recording output FPS is maximum FPS of the requested
FPS range. The application can submit this request list directly to an active high speed
capture session to achieve high speed video recording. When only preview or recording
Surface is specified, this method will return a list of request that have the same controls
and output targets for all requests.
Submitting a request list created by this method to a normal capture session will result
in an IllegalArgumentException if the high speed
FPS range is not supported by
CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES.
| Parameters | |
|---|---|
request |
CaptureRequest:
The high speed capture request that will be used to generate the high speed
request list. |
| Returns | |
|---|---|
List<CaptureRequest> |
A unmodifiable CaptureRequest list that is suitable for constrained high speed capture. |
| Throws | |
|---|---|
IllegalArgumentException |
if the set of output Surfaces in the request do not meet the high speed video capability requirements, or the camera device doesn't support high speed video capability, or the request doesn't meet the high speed video capability requirements, or the request doesn't contain the required controls for high speed capture. |
CameraAccessException |
if the camera device is no longer connected or has encountered a fatal error |
IllegalStateException |
if the camera device has been closed |
Developers