使用 CameraX 1.5 进行高速拍摄和慢动作视频拍摄

// build.gradle.kts (Module: app)

dependencies {

    val camerax_version = "1.5.1"


    implementation("androidx.camera:camera-core:$camerax_version")

    implementation("androidx.camera:camera-camera2:$camerax_version")

    implementation("androidx.camera:camera-lifecycle:$camerax_version")

    implementation("androidx.camera:camera-video:$camerax_version")

    implementation("androidx.camera:camera-view:$camerax_version")

}

@kotlin.OptIn(ExperimentalSessionConfig::class, ExperimentalHighSpeedVideo::class)

// Add the OptIn annotation at the top of your function or class

@kotlin.OptIn(ExperimentalSessionConfig::class, ExperimentalHighSpeedVideo::class)

private suspend fun setupCamera() {

    // Asynchronously get the CameraProvider

    val cameraProvider = ProcessCameraProvider.awaitInstance(this)



    // -- CHECK CAPABILITIES --

    val cameraInfo = cameraProvider.getCameraInfo(CameraSelector.DEFAULT_BACK_CAMERA)

    val videoCapabilities = Recorder.getHighSpeedVideoCapabilities(cameraInfo)

    if (videoCapabilities == null) {

        // This camera device does not support high-speed video.

        return

    }




    // -- CREATE USE CASES --

    val preview = Preview.Builder().build()    


    // You can create a Recorder with default settings.

    // CameraX will automatically select a suitable quality.

    val recorder = Recorder.Builder().build()


    // Alternatively, to use a specific resolution, you can configure the
    // Recorder with a QualitySelector. This is useful if your app has
    // specific resolution requirements or you want to offer user
    // preferences. 

    // To use a specific quality, you can uncomment the following lines.

    // Get the list of qualities supported for high-speed video. 

    // val supportedQualities = videoCapabilities.getSupportedQualities(DynamicRange.SDR)

    // Build the Recorder using the quality from the supported list.

    // val recorderWithQuality = Recorder.Builder()

    //     .setQualitySelector(QualitySelector.from(supportedQualities.first()))

    //     .build()



    // Create the VideoCapture use case, using either recorder or recorderWithQuality

    val videoCapture = VideoCapture.withOutput(recorder)

    // Now you are ready to configure the session for your desired output...

}

// Create a builder for the high-speed session

val sessionConfigBuilder = HighSpeedVideoSessionConfig.Builder(videoCapture)

    .setPreview(preview)


// Query and apply a supported frame rate. Common supported frame rates include 120 and 240 fps.

val supportedFrameRateRanges =

    cameraInfo.getSupportedFrameRateRanges(sessionConfigBuilder.build())


sessionConfigBuilder.setFrameRateRange(supportedFrameRateRanges.first())

// Create a builder for the high-speed session

val sessionConfigBuilder = HighSpeedVideoSessionConfig.Builder(videoCapture)

    .setPreview(preview)



// This is the key: enable automatic slow-motion!

sessionConfigBuilder.setSlowMotionEnabled(true)



// Query and apply a supported frame rate. Common supported frame rates include 120, 240, and 480 fps.

val supportedFrameRateRanges =

   cameraInfo.getSupportedFrameRateRanges(sessionConfigBuilder.build())

sessionConfigBuilder.setFrameRateRange(supportedFrameRateRanges.first())

// Bind the session config to the lifecycle

cameraProvider.bindToLifecycle(

    this as LifecycleOwner,

    CameraSelector.DEFAULT_BACK_CAMERA,

    sessionConfigBuilder.build() // Bind the config object from Option A or B

)



// Start the recording using the VideoCapture use case

val recording = videoCapture.output

    .prepareRecording(context, outputOptions) // See docs for creating outputOptions

    .start(ContextCompat.getMainExecutor(context)) { recordEvent ->

        // Handle recording events (e.g., Start, Pause, Finalize)

    }