Android Camera2Video Sample (Kotlin)

This sample shows how to record video using the new Camera2 API in Android Lollipop.

Introduction

Android Lollipop introduced a new camera API, called camera2. This sample uses CameraDevice
and CameraCaptureSession to record video. It also uses a custom TextureView to render the output.

The main steps are:

1. Create a custom TextureView class and add it to the layout. The purpose of the custom TextureView is
   to be able to draw itself according to an aspect ratio, which is set via a public method. Additionally,
   the onMeasure(int widthMeasureSpec, int heightMeasureSpec) method is overridden, using the aspect ratio.
2. Implement a TextureView.SurfaceTextureListener on your TextureView, and override its
   onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int width, int height) method to calculate
   the matrix to apply to the TextureView so the camera output fits. Use the method setTransform(matrix) on
   the TextureView.
3. Implement a CameraDevice.StateCallback to receive events about changes of the state of the
   camera device. Override its methods to set your CameraDevice instance, start the preview, and stop
   and release the camera.
4. When starting the preview, set up the MediaRecorder to accept video format.
5. Then, set up a CaptureRequest.Builder using createCaptureRequest(CameraDevice.TEMPLATE_RECORD)
   on your CameraDevice instance.
6. Then, implement a CameraCaptureSession.StateCallback, using the method
   createCaptureSession(surfaces, new CameraCaptureSession.StateCallback(){}) on your CameraDevice instance,
   where surfaces is a list consisting of the surface view of your TextureView and the surface of
   your MediaRecorder instance.
7. Use start() and stop() methods on your MediaRecorder instance to actually start and stop the recording.
8. Lastly, set up and clean up your camera device in onResume() and onPause().

Pre-requisites

• Android SDK 27
• Android Support Repository

Screenshots

Getting Started

This sample uses the Gradle build system. To build this project, use the
"gradlew build" command or use "Import Project" in Android Studio.

Support

• Google+ Community: https://plus.google.com/communities/105153134372062985968
• Stack Overflow: http://stackoverflow.com/questions/tagged/android

If you've found an error in this sample, please file an issue:
https://github.com/googlesamples/android-Camera2Video

Patches are encouraged, and may be submitted by forking this project and
submitting a pull request through GitHub. Please see CONTRIBUTING.md for more details.

License

Copyright 2018 The Android Open Source Project, Inc.

Licensed to the Apache Software Foundation (ASF) under one or more contributor
license agreements. See the NOTICE file distributed with this work for
additional information regarding copyright ownership. The ASF licenses this
file to you under the Apache License, Version 2.0 (the "License"); you may not
use this file except in compliance with the License. You may obtain a copy of
the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
License for the specific language governing permissions and limitations under
the License.