要分析 Android CameraX 的图像流,可以按照以下步骤进行:
build.gradle
文件中添加 CameraX 的依赖项:implementation 'androidx.camera:camera-core:1.0.0-beta07'
implementation 'androidx.camera:camera-camera2:1.0.0-beta07'
implementation 'androidx.camera:camera-lifecycle:1.0.0-beta07'
implementation 'androidx.camera:camera-view:1.0.0-alpha26'
PreviewView
用于显示相机预览:
val previewView: PreviewView = findViewById(R.id.previewView)
val cameraProviderFuture = ProcessCameraProvider.getInstance(this)
cameraProviderFuture.addListener({
val cameraProvider: ProcessCameraProvider = cameraProviderFuture.get()
val preview = Preview.Builder().build().also {
it.setSurfaceProvider(previewView.surfaceProvider)
}
val imageAnalyzer = ImageAnalysis.Builder()
.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST)
.build()
.also {
it.setAnalyzer(Executors.newSingleThreadExecutor(), { image ->
// 在这里进行图像分析的逻辑
// 可以使用 image.planes 获取图像的不同平面
// 例如:val pixelBuffer = image.planes[0].buffer
})
}
val cameraSelector = CameraSelector.DEFAULT_BACK_CAMERA
try {
cameraProvider.unbindAll()
cameraProvider.bindToLifecycle(this, cameraSelector, preview, imageAnalyzer)
} catch (exc: Exception) {
Log.e(TAG, "无法绑定相机", exc)
}
}, ContextCompat.getMainExecutor(this))
image.planes
获取图像的不同平面。例如,以下代码将图像转换为 Bitmap 并显示在 ImageView 中:val pixelBuffer = image.planes[0].buffer
val rowStride = image.planes[0].rowStride
val pixelStride = image.planes[0].pixelStride
val width = image.width
val height = image.height
val bitmap = Bitmap.createBitmap(width + pixelStride / 2, height, Bitmap.Config.ARGB_8888)
bitmap.copyPixelsFromBuffer(pixelBuffer)
runOnUiThread {
imageView.setImageBitmap(bitmap)
}
image.close()
这样,你就可以使用 CameraX 分析 Android 的图像流了。请注意,为了更好地处理图像分析,你可能需要在 setAnalyzer
方法中使用一个单独的线程池来执行图像处理逻辑,并在适当的时候释放图像资源。