我可以用CameraX (Android Jetpack)录制视频吗？

Question

谷歌已经发布了新的CameraX库，作为Jetpack的一部分。它看起来很适合拍照，但我的用例也需要制作视频，我试着用谷歌搜索，但什么也找不到。

那么，是否可以使用CameraX Jetpack库来录制视频呢？

Answer 1

是的，我们可以使用CameraX录制视频。我尝试在CameraX的Github demo的帮助下实现自己的功能。请参考下面的代码，希望它能对你有所帮助。

CameraX中视频的配置：

val videoCaptureConfig = VideoCaptureConfig.Builder().apply {
    setLensFacing(lensFacing)
    setTargetAspectRatio(screenAspectRatio)
    setTargetRotation(viewFinder.display.rotation)

}.build()

videoCapture = VideoCapture(videoCaptureConfig)

CameraX.bindToLifecycle(this, preview, imageCapture, videoCapture)

开始录制视频的：

videoCapture?.startRecording(videoFile, object : VideoCapture.OnVideoSavedListener {
        override fun onVideoSaved(file: File?) {
            Log.i(javaClass.simpleName, "Video File : $file")
        }

        override fun onError(useCaseError: VideoCapture.UseCaseError?, message: String?, cause: Throwable?) {
            Log.i(javaClass.simpleName, "Video Error: $message")
        }

    })

停止视频录制的：

videoCapture?.stopRecording()

与我在Github问题评论中提到的相同：https://github.com/android/camera/issues/2#issuecomment-490773932

备注：使用CameraX实现视频录制的代码可能有所不同。因为上面的代码是由我开发的，没有任何其他参考，而不是Github Demo。

请查看截至2019年5月14日 Oscar Wahltinez 对此答案的重要评论

Answer 2

这是我的解决方案

//Versions in Gradle
def camerax_version = "1.0.0-beta06"
def camera_extensions = "1.0.0-alpha13"

private lateinit var videoCapture: VideoCapture
private lateinit var viewFinder: PreviewView
private lateinit var outputDirectory: File
private var lensFacing: Int = CameraSelector.LENS_FACING_FRONT


private val executor = Executors.newSingleThreadExecutor()
private var isRecording = false
private var camera: Camera? = null
private lateinit var cameraProviderFuture: ListenableFuture<ProcessCameraProvider>


//onCreate
viewFinder = preview_video_view
    runWithPermissions(*permissions) {
        startCamera(view.context)
        initClicks()
    }

 @SuppressLint("RestrictedApi", "UnsafeExperimentalUsageError")
private fun startCamera(context: Context) {
    outputDirectory = getOutputDirectory(context)
    cameraProviderFuture = ProcessCameraProvider.getInstance(context)

    val cameraSelector = CameraSelector.Builder().requireLensFacing(lensFacing).build()

    // Create a configuration object for the video use case
    val videoCaptureConfig = VideoCaptureConfig.Builder().apply {
        setTargetRotation(viewFinder.display.rotation)
        setCameraSelector(cameraSelector)
    }


    //CameraX.initialize(context, this.cameraXConfig) 

    videoCapture = VideoCapture(videoCaptureConfig.useCaseConfig)

    val preview: Preview = Preview.Builder().apply {
        setTargetAspectRatio(AspectRatio.RATIO_16_9)
        setTargetRotation(viewFinder.display.rotation)
    }.build()
    preview.setSurfaceProvider(viewFinder.createSurfaceProvider())

    cameraProviderFuture.addListener(Runnable {
        val cameraProvider = cameraProviderFuture.get()
        camera = cameraProvider.bindToLifecycle(
            viewLifecycleOwner,
            cameraSelector,
            preview,
            videoCapture
        )
        
    }, ContextCompat.getMainExecutor(context))
}

@SuppressLint("RestrictedApi")
private fun startRecording() {
    val file = createFile(
        outputDirectory,
        FILENAME,
        VIDEO_EXTENSION
    )

    videoCapture.startRecording(
        file,
        executor,
        object : VideoCapture.OnVideoSavedCallback {
            override fun onVideoSaved(file: File) {
                Handler(Looper.getMainLooper()).post {
                    showMessage(file.name + " is saved")
                }
            }

            override fun onError(videoCaptureError: Int, message: String, cause: Throwable?) {
                Handler(Looper.getMainLooper()).post {
                    showMessage(videoCaptureError.toString() + " " + message)
                }
            }
        }
    )
}

@SuppressLint("RestrictedApi")
private fun stopRecording() {
    videoCapture.stopRecording()
}

 override fun getCameraXConfig(): CameraXConfig {
    return Camera2Config.defaultConfig()
}

companion object {
    private const val FILENAME = "yyyy_MM_dd_HH_mm_ss"
    private const val VIDEO_EXTENSION = ".mp4"

    private val permissions = arrayOf(
        Manifest.permission.WRITE_EXTERNAL_STORAGE,
        Manifest.permission.READ_EXTERNAL_STORAGE,
        Manifest.permission.CAMERA,
        Manifest.permission.RECORD_AUDIO
    )

    fun getOutputDirectory(context: Context): File {
        val appContext = context.applicationContext
        val mediaDir = appContext.externalMediaDirs.firstOrNull()?.let {
            File(it, appContext.resources.getString(R.string.app_name)).apply { mkdirs() }
        }
        return if (mediaDir != null && mediaDir.exists()) mediaDir else appContext.filesDir
    }

    fun createFile(baseFolder: File, format: String, extension: String) =
        File(baseFolder, SimpleDateFormat(format, Locale.US)
            .format(System.currentTimeMillis()) + extension)
}

Answer 3

更新Patel Pinkal的答案。测试版发布后，我们不能再使用VideoCaptureConfig.Builder()，而是使用如下代码：

 videoCapture = VideoCapture.Builder().apply {
     // init config here
 }.build()