1 /*
2  * Copyright 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.hardware.camera2;
18 
19 import android.annotation.NonNull;
20 import android.hardware.camera2.params.StreamConfigurationMap;
21 
22 import java.util.List;
23 
24 /**
25  * A constrained high speed capture session for a {@link CameraDevice}, used for capturing high
26  * speed images from the {@link CameraDevice} for high speed video recording use case.
27  * <p>
28  * A CameraHighSpeedCaptureSession is created by providing a set of target output surfaces to
29  * {@link CameraDevice#createConstrainedHighSpeedCaptureSession}, Once created, the session is
30  * active until a new session is created by the camera device, or the camera device is closed.
31  * </p>
32  * <p>
33  * An active high speed capture session is a specialized capture session that is only targeted at
34  * high speed video recording (>=120fps) use case if the camera device supports high speed video
35  * capability (i.e., {@link CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES} contains
36  * {@link CameraMetadata#REQUEST_AVAILABLE_CAPABILITIES_CONSTRAINED_HIGH_SPEED_VIDEO}). It only
37  * accepts request lists created via {@link #createHighSpeedRequestList}, and the request list can
38  * only be submitted to this session via {@link CameraCaptureSession#captureBurst captureBurst}, or
39  * {@link CameraCaptureSession#setRepeatingBurst setRepeatingBurst}. See
40  * {@link CameraDevice#createConstrainedHighSpeedCaptureSession} for more details of the
41  * limitations.
42  * </p>
43  * <p>
44  * Creating a session is an expensive operation and can take several hundred milliseconds, since it
45  * requires configuring the camera device's internal pipelines and allocating memory buffers for
46  * sending images to the desired targets. Therefore the setup is done asynchronously, and
47  * {@link CameraDevice#createConstrainedHighSpeedCaptureSession} will send the ready-to-use
48  * CameraCaptureSession to the provided listener's
49  * {@link CameraCaptureSession.StateCallback#onConfigured} callback. If configuration cannot be
50  * completed, then the {@link CameraCaptureSession.StateCallback#onConfigureFailed} is called, and
51  * the session will not become active.
52  * </p>
53  * <!--
54  * <p>
55  * Any capture requests (repeating or non-repeating) submitted before the session is ready will be
56  * queued up and will begin capture once the session becomes ready. In case the session cannot be
57  * configured and {@link CameraCaptureSession.StateCallback#onConfigureFailed onConfigureFailed} is
58  * called, all queued capture requests are discarded.  </p>
59  * -->
60  * <p>
61  * If a new session is created by the camera device, then the previous session is closed, and its
62  * associated {@link CameraCaptureSession.StateCallback#onClosed onClosed} callback will be
63  * invoked. All of the session methods will throw an IllegalStateException if called once the
64  * session is closed.
65  * </p>
66  * <p>
67  * A closed session clears any repeating requests (as if {@link #stopRepeating} had been called),
68  * but will still complete all of its in-progress capture requests as normal, before a newly created
69  * session takes over and reconfigures the camera device.
70  * </p>
71  */
72 public abstract class CameraConstrainedHighSpeedCaptureSession extends CameraCaptureSession {
73 
74     /**
75      * <p>Create a unmodifiable list of requests that is suitable for constrained high speed capture
76      * session streaming.</p>
77      *
78      * <p>High speed video streaming creates significant performance pressure on the camera device,
79      * so to achieve efficient high speed streaming, the camera device may have to aggregate
80      * multiple frames together. This means requests must be sent in batched groups, with all
81      * requests sharing the same settings. This method takes the list of output target
82      * Surfaces (subject to the output Surface requirements specified by the constrained high speed
83      * session) and a {@link CaptureRequest request}, and generates a request list that has the same
84      * controls for each request. The input {@link CaptureRequest request} must contain the target
85      * output Surfaces and target high speed FPS range that is one of the
86      * {@link StreamConfigurationMap#getHighSpeedVideoFpsRangesFor} for the Surface size.</p>
87      *
88      * <p>If both preview and recording Surfaces are specified in the {@code request}, the
89      * {@link CaptureRequest#CONTROL_AE_TARGET_FPS_RANGE target FPS range} in the input
90      * {@link CaptureRequest request} must be a fixed frame rate FPS range, where the
91      * {@link android.util.Range#getLower minimal FPS} ==
92      * {@link android.util.Range#getUpper() maximum FPS}. The created request list will contain
93      * a interleaved request pattern such that the preview output FPS is at least 30fps, the
94      * recording output FPS is {@link android.util.Range#getUpper() maximum FPS} of the requested
95      * FPS range. The application can submit this request list directly to an active high speed
96      * capture session to achieve high speed video recording. When only preview or recording
97      * Surface is specified, this method will return a list of request that have the same controls
98      * and output targets for all requests.</p>
99      *
100      * <p>Submitting a request list created by this method to a normal capture session will result
101      * in an {@link IllegalArgumentException} if the high speed
102      * {@link CaptureRequest#CONTROL_AE_TARGET_FPS_RANGE FPS range} is not supported by
103      * {@link CameraCharacteristics#CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES}.</p>
104      *
105      * @param request The high speed capture request that will be used to generate the high speed
106      *                request list.
107      * @return A unmodifiable CaptureRequest list that is suitable for constrained high speed
108      *         capture.
109      *
110      * @throws IllegalArgumentException if the set of output Surfaces in the request do not meet the
111      *                                  high speed video capability requirements, or the camera
112      *                                  device doesn't support high speed video capability, or the
113      *                                  request doesn't meet the high speed video capability
114      *                                  requirements, or the request doesn't contain the required
115      *                                  controls for high speed capture.
116      * @throws CameraAccessException if the camera device is no longer connected or has
117      *                               encountered a fatal error
118      * @throws IllegalStateException if the camera device has been closed
119      *
120      * @see CameraDevice#createConstrainedHighSpeedCaptureSession
121      * @see CaptureRequest#CONTROL_AE_TARGET_FPS_RANGE
122      * @see android.hardware.camera2.params.StreamConfigurationMap#getHighSpeedVideoSizes
123      * @see android.hardware.camera2.params.StreamConfigurationMap#getHighSpeedVideoFpsRangesFor
124      * @see CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES
125      * @see CameraMetadata#REQUEST_AVAILABLE_CAPABILITIES_CONSTRAINED_HIGH_SPEED_VIDEO
126      */
127     @NonNull
createHighSpeedRequestList( @onNull CaptureRequest request)128     public abstract List<CaptureRequest> createHighSpeedRequestList(
129             @NonNull CaptureRequest request) throws CameraAccessException;
130 
131 }
132