使用 cameraX 的 PreviewView 捕获叠加层
capture overlay using PreviewView of cameraX
我正在尝试捕捉图像捕捉中包含叠加层的图片。我能够使用 cameraView.overlay.add(binding.textView)
将覆盖设置为 previewView
。然而,当尝试使用 imageCapture
保存图像时它没有保存,只保存了图片而不是叠加层。如何使用 PreviewView
of camera x.
保存包含叠加层的图像
请不要将其标记为重复。我研究了很多,大多数在线示例都使用旧的 camera
api,它不适用于 camera x 库。任何帮助表示赞赏。提前致谢。
这是我的代码
<FrameLayout
android:id="@+id/camera_wrapper"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toTopOf="@id/space1"
app:layout_constraintBottom_toBottomOf="@id/space">
<androidx.camera.view.PreviewView
android:id="@+id/camera_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<TextView
android:id="@+id/text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Hello world"
android:textSize="42sp"
android:textColor="@android:color/holo_green_dark"/>
</FrameLayout>
private lateinit var outputDirectory: File
private lateinit var cameraExecutor: ExecutorService
private var preview: Preview? = null
private var lensFacing: Int = CameraSelector.LENS_FACING_FRONT
private var imageCapture: ImageCapture? = null
private var camera: Camera? = null
private var cameraProvider: ProcessCameraProvider? = null
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
outputDirectory = getOutputDirectory()
cameraExecutor = Executors.newSingleThreadExecutor()
}
private fun setupCamera() {
val cameraProviderFuture = ProcessCameraProvider.getInstance(requireContext())
cameraProviderFuture.addListener(
Runnable {
// Used to bind the lifecycle of cameras to the lifecycle owner
cameraProvider = cameraProviderFuture.get()
// Get screen metrics used to setup camera for full screen resolution
val metrics = DisplayMetrics().also { binding.cameraView.display.getRealMetrics(it) }
Timber.d("Screen metrics: ${metrics.widthPixels} x ${metrics.heightPixels}")
val screenAspectRatio = aspectRatio(metrics.widthPixels, metrics.heightPixels)
Timber.d("Preview aspect ratio: $screenAspectRatio")
val rotation = binding.cameraView.display.rotation
// CameraProvider
val cameraProvider = cameraProvider
?: throw IllegalStateException("Camera initialization failed.")
// CameraSelector
val cameraSelector = CameraSelector.Builder().requireLensFacing(lensFacing).build()
// add text overlay *---------*
binding.cameraView.overlay.add(binding.textView)
// Preview
preview = Preview.Builder()
// We request aspect ratio but no resolution
.setTargetAspectRatio(screenAspectRatio)
// Set initial target rotation
.setTargetRotation(rotation)
.build()
// ImageCapture
imageCapture = ImageCapture.Builder()
.setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY)
// We request aspect ratio but no resolution to match preview config, but letting
// CameraX optimize for whatever specific resolution best fits our use cases
.setTargetAspectRatio(screenAspectRatio)
// Set initial target rotation, we will have to call this again if rotation changes
// during the lifecycle of this use case
.setTargetRotation(rotation)
.build()
// Must unbind the use-cases before rebinding them
cameraProvider.unbindAll()
try {
// A variable number of use-cases can be passed here -
// camera provides access to CameraControl & CameraInfo
camera = cameraProvider.bindToLifecycle(this, cameraSelector, preview, imageCapture)
// Attach the viewfinder's surface provider to preview use case
preview?.setSurfaceProvider(binding.cameraView.surfaceProvider)
} catch (exc: Exception) {
Toast.makeText(requireContext(), "Something went wrong. Please try again.", Toast.LENGTH_SHORT).show()
findNavController().navigateUp()
}
},
ContextCompat.getMainExecutor(requireContext())
)
}
private fun takePhoto() {
imageCapture?.let { imageCapture ->
// Create output file to hold the image
val photoFile = createFile(outputDirectory, FILENAME, PHOTO_EXTENSION)
// Setup image capture metadata
val metadata = ImageCapture.Metadata().apply {
// Mirror image when using the front camera
isReversedHorizontal = lensFacing == CameraSelector.LENS_FACING_FRONT
}
// Create output options object which contains file + metadata
val outputOptions = ImageCapture.OutputFileOptions.Builder(photoFile)
.setMetadata(metadata)
.build()
// Setup image capture listener which is triggered after photo has been taken
imageCapture.takePicture(outputOptions, cameraExecutor, object : ImageCapture.OnImageSavedCallback {
override fun onError(exc: ImageCaptureException) {
Timber.e(exc, "Photo capture failed: ${exc.message}")
}
override fun onImageSaved(output: ImageCapture.OutputFileResults) {
val savedUri = output.savedUri ?: Uri.fromFile(photoFile)
Timber.d("Photo capture succeeded: $savedUri")
// Implicit broadcasts will be ignored for devices running API level >= 24
// so if you only target API level 24+ you can remove this statement
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N) {
requireActivity()
.sendBroadcast(Intent(android.hardware.Camera.ACTION_NEW_PICTURE, savedUri))
}
// If the folder selected is an external media directory, this is
// unnecessary but otherwise other apps will not be able to access our
// images unless we scan them using [MediaScannerConnection]
val mimeType = MimeTypeMap.getSingleton()
.getMimeTypeFromExtension(savedUri.toFile().extension)
MediaScannerConnection.scanFile(
context,
arrayOf(savedUri.toFile().absolutePath),
arrayOf(mimeType)
) { _, uri ->
Timber.d("Image capture scanned into media store: $uri")
}
}
})
}
}
您必须自己将文字叠加在图片上。我建议使用 takePicture(Executor, …) 将 Jpeg 放入内存;然后,使用其中一个库(不属于 Android 框架,也不属于 Jetpack)覆盖您的文本,并将结果保存在文件中。
如果可以在图像质量上妥协,可以在位图上绘制 Jpeg canvas,然后在上面绘制文本。
使用这个插件https://github.com/huangyz0918/AndroidWM
.另外,如果你想自己搭建这个可以帮助你参考。
简单的用法如下
WatermarkText watermarkText = new WatermarkText(inputText)
.setPositionX(0.5)
.setPositionY(0.5)
.setTextColor(Color.WHITE)
.setTextFont(R.font.champagne)
.setTextShadow(0.1f, 5, 5, Color.BLUE)
.setTextAlpha(150)
.setRotation(30)
.setTextSize(20);
val bmFinal: Bitmap = WatermarkBuilder
.create(applicationContext, capturedImageBitmap)
.loadWatermarkText(watermarkText)
.watermark
.outputImage
// ##### Then save it #########
fun saveImage(bitmap: Bitmap, photoFile: File) {
val output: OutputStream = FileOutputStream(photoFile)
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, output)
output.flush()
output.close()
Toast.makeText(
this@MainActivity,
"Imaged Saved at ${photoFile.absolutePath}",
Toast.LENGTH_LONG
).show()
}
val photoFile = File(
outputDirectory,
SimpleDateFormat(
FILENAME_FORMAT, Locale.US
).format(System.currentTimeMillis()) + ".jpg"
)
saveImage(bmFinal, photoFile)
也许你可以使用 CameraSource class 并将你的 preview/overlay 放在里面 :
val cameraSource = CameraSource.Builder(requireContext(),FakeDetector()).build()
cameraSource.start(your_preview_overlay)
在你有 API 之后:
takePicture(CameraSource.ShutterCallback shutter, CameraSource.PictureCallback jpeg)
相机源 (https://developers.google.com/android/reference/com/google/android/gms/vision/CameraSource) 用于检测,但您可以创建一个假检测器(没有可检测的)。
@alexcohn's answer 是首选,如果你不能失去质量。但是,如果质量不是什么大问题,那么您可以这样做。
<FrameLayout
android:id="@+id/camera_wrapper"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toTopOf="@id/space1"
app:layout_constraintBottom_toBottomOf="@id/space">
<androidx.camera.view.PreviewView
android:id="@+id/camera_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ImageView
android:id="@+id/selfie"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:visibility="gone"
tools:visibility="visible"
tools:background="@color/gray" />
<ImageView
android:id="@+id/overlay"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
tools:src="@drawable/full_frame_gd" />
</FrameLayout>
PreviewView
有一个内置功能,可以为您提供预览的位图
val bitmap = binding.cameraView.bitmap
binding.selfie.setImageBitmap(bitmap)
binding.selfie.visibility = View.VISIBLE
cameraExecutor.shutdown()
binding.cameraView.visibility = View.GONE
现在您有两张图片,一张用于 selfie
,一张用于 overlay
。您无法拍摄预览视图的屏幕截图。它有一些限制,我不太确定。但是,我相信可能有解决办法。
从这里您可以像这样截取两个组合图像视图的屏幕截图
private fun captureView(view: View, window: Window, bitmapCallback: (Bitmap)->Unit) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
// Above Android O, use PixelCopy
val bitmap = Bitmap.createBitmap(view.width, view.height, Bitmap.Config.ARGB_8888)
val location = IntArray(2)
view.getLocationInWindow(location)
PixelCopy.request(
window,
Rect(
location[0],
location[1],
location[0] + view.width,
location[1] + view.height
),
bitmap,
{
if (it == PixelCopy.SUCCESS) {
bitmapCallback.invoke(bitmap)
}
},
Handler(Looper.getMainLooper()) )
} else {
val tBitmap = Bitmap.createBitmap(
view.width, view.height, Bitmap.Config.RGB_565
)
val canvas = Canvas(tBitmap)
view.draw(canvas)
canvas.setBitmap(null)
bitmapCallback.invoke(tBitmap)
}
}
在 takePhoto() 函数中,您可以删除 imageCapture.takePicture
逻辑并将其替换为这个。
Handler(Looper.getMainLooper()).postDelayed({
captureView(binding.cameraWrapper, requireActivity().window) {
// your new bitmap with overlay is here and you can save it to file just like any other bitmaps.
}
}, 500)
我正在尝试捕捉图像捕捉中包含叠加层的图片。我能够使用 cameraView.overlay.add(binding.textView)
将覆盖设置为 previewView
。然而,当尝试使用 imageCapture
保存图像时它没有保存,只保存了图片而不是叠加层。如何使用 PreviewView
of camera x.
请不要将其标记为重复。我研究了很多,大多数在线示例都使用旧的 camera
api,它不适用于 camera x 库。任何帮助表示赞赏。提前致谢。
这是我的代码
<FrameLayout
android:id="@+id/camera_wrapper"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toTopOf="@id/space1"
app:layout_constraintBottom_toBottomOf="@id/space">
<androidx.camera.view.PreviewView
android:id="@+id/camera_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<TextView
android:id="@+id/text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Hello world"
android:textSize="42sp"
android:textColor="@android:color/holo_green_dark"/>
</FrameLayout>
private lateinit var outputDirectory: File
private lateinit var cameraExecutor: ExecutorService
private var preview: Preview? = null
private var lensFacing: Int = CameraSelector.LENS_FACING_FRONT
private var imageCapture: ImageCapture? = null
private var camera: Camera? = null
private var cameraProvider: ProcessCameraProvider? = null
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
outputDirectory = getOutputDirectory()
cameraExecutor = Executors.newSingleThreadExecutor()
}
private fun setupCamera() {
val cameraProviderFuture = ProcessCameraProvider.getInstance(requireContext())
cameraProviderFuture.addListener(
Runnable {
// Used to bind the lifecycle of cameras to the lifecycle owner
cameraProvider = cameraProviderFuture.get()
// Get screen metrics used to setup camera for full screen resolution
val metrics = DisplayMetrics().also { binding.cameraView.display.getRealMetrics(it) }
Timber.d("Screen metrics: ${metrics.widthPixels} x ${metrics.heightPixels}")
val screenAspectRatio = aspectRatio(metrics.widthPixels, metrics.heightPixels)
Timber.d("Preview aspect ratio: $screenAspectRatio")
val rotation = binding.cameraView.display.rotation
// CameraProvider
val cameraProvider = cameraProvider
?: throw IllegalStateException("Camera initialization failed.")
// CameraSelector
val cameraSelector = CameraSelector.Builder().requireLensFacing(lensFacing).build()
// add text overlay *---------*
binding.cameraView.overlay.add(binding.textView)
// Preview
preview = Preview.Builder()
// We request aspect ratio but no resolution
.setTargetAspectRatio(screenAspectRatio)
// Set initial target rotation
.setTargetRotation(rotation)
.build()
// ImageCapture
imageCapture = ImageCapture.Builder()
.setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY)
// We request aspect ratio but no resolution to match preview config, but letting
// CameraX optimize for whatever specific resolution best fits our use cases
.setTargetAspectRatio(screenAspectRatio)
// Set initial target rotation, we will have to call this again if rotation changes
// during the lifecycle of this use case
.setTargetRotation(rotation)
.build()
// Must unbind the use-cases before rebinding them
cameraProvider.unbindAll()
try {
// A variable number of use-cases can be passed here -
// camera provides access to CameraControl & CameraInfo
camera = cameraProvider.bindToLifecycle(this, cameraSelector, preview, imageCapture)
// Attach the viewfinder's surface provider to preview use case
preview?.setSurfaceProvider(binding.cameraView.surfaceProvider)
} catch (exc: Exception) {
Toast.makeText(requireContext(), "Something went wrong. Please try again.", Toast.LENGTH_SHORT).show()
findNavController().navigateUp()
}
},
ContextCompat.getMainExecutor(requireContext())
)
}
private fun takePhoto() {
imageCapture?.let { imageCapture ->
// Create output file to hold the image
val photoFile = createFile(outputDirectory, FILENAME, PHOTO_EXTENSION)
// Setup image capture metadata
val metadata = ImageCapture.Metadata().apply {
// Mirror image when using the front camera
isReversedHorizontal = lensFacing == CameraSelector.LENS_FACING_FRONT
}
// Create output options object which contains file + metadata
val outputOptions = ImageCapture.OutputFileOptions.Builder(photoFile)
.setMetadata(metadata)
.build()
// Setup image capture listener which is triggered after photo has been taken
imageCapture.takePicture(outputOptions, cameraExecutor, object : ImageCapture.OnImageSavedCallback {
override fun onError(exc: ImageCaptureException) {
Timber.e(exc, "Photo capture failed: ${exc.message}")
}
override fun onImageSaved(output: ImageCapture.OutputFileResults) {
val savedUri = output.savedUri ?: Uri.fromFile(photoFile)
Timber.d("Photo capture succeeded: $savedUri")
// Implicit broadcasts will be ignored for devices running API level >= 24
// so if you only target API level 24+ you can remove this statement
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N) {
requireActivity()
.sendBroadcast(Intent(android.hardware.Camera.ACTION_NEW_PICTURE, savedUri))
}
// If the folder selected is an external media directory, this is
// unnecessary but otherwise other apps will not be able to access our
// images unless we scan them using [MediaScannerConnection]
val mimeType = MimeTypeMap.getSingleton()
.getMimeTypeFromExtension(savedUri.toFile().extension)
MediaScannerConnection.scanFile(
context,
arrayOf(savedUri.toFile().absolutePath),
arrayOf(mimeType)
) { _, uri ->
Timber.d("Image capture scanned into media store: $uri")
}
}
})
}
}
您必须自己将文字叠加在图片上。我建议使用 takePicture(Executor, …) 将 Jpeg 放入内存;然后,使用其中一个库(不属于 Android 框架,也不属于 Jetpack)覆盖您的文本,并将结果保存在文件中。
如果可以在图像质量上妥协,可以在位图上绘制 Jpeg canvas,然后在上面绘制文本。
使用这个插件https://github.com/huangyz0918/AndroidWM .另外,如果你想自己搭建这个可以帮助你参考。
简单的用法如下
WatermarkText watermarkText = new WatermarkText(inputText)
.setPositionX(0.5)
.setPositionY(0.5)
.setTextColor(Color.WHITE)
.setTextFont(R.font.champagne)
.setTextShadow(0.1f, 5, 5, Color.BLUE)
.setTextAlpha(150)
.setRotation(30)
.setTextSize(20);
val bmFinal: Bitmap = WatermarkBuilder
.create(applicationContext, capturedImageBitmap)
.loadWatermarkText(watermarkText)
.watermark
.outputImage
// ##### Then save it #########
fun saveImage(bitmap: Bitmap, photoFile: File) {
val output: OutputStream = FileOutputStream(photoFile)
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, output)
output.flush()
output.close()
Toast.makeText(
this@MainActivity,
"Imaged Saved at ${photoFile.absolutePath}",
Toast.LENGTH_LONG
).show()
}
val photoFile = File(
outputDirectory,
SimpleDateFormat(
FILENAME_FORMAT, Locale.US
).format(System.currentTimeMillis()) + ".jpg"
)
saveImage(bmFinal, photoFile)
也许你可以使用 CameraSource class 并将你的 preview/overlay 放在里面 :
val cameraSource = CameraSource.Builder(requireContext(),FakeDetector()).build()
cameraSource.start(your_preview_overlay)
在你有 API 之后:
takePicture(CameraSource.ShutterCallback shutter, CameraSource.PictureCallback jpeg)
相机源 (https://developers.google.com/android/reference/com/google/android/gms/vision/CameraSource) 用于检测,但您可以创建一个假检测器(没有可检测的)。
@alexcohn's answer 是首选,如果你不能失去质量。但是,如果质量不是什么大问题,那么您可以这样做。
<FrameLayout
android:id="@+id/camera_wrapper"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toTopOf="@id/space1"
app:layout_constraintBottom_toBottomOf="@id/space">
<androidx.camera.view.PreviewView
android:id="@+id/camera_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ImageView
android:id="@+id/selfie"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:visibility="gone"
tools:visibility="visible"
tools:background="@color/gray" />
<ImageView
android:id="@+id/overlay"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
tools:src="@drawable/full_frame_gd" />
</FrameLayout>
PreviewView
有一个内置功能,可以为您提供预览的位图
val bitmap = binding.cameraView.bitmap
binding.selfie.setImageBitmap(bitmap)
binding.selfie.visibility = View.VISIBLE
cameraExecutor.shutdown()
binding.cameraView.visibility = View.GONE
现在您有两张图片,一张用于 selfie
,一张用于 overlay
。您无法拍摄预览视图的屏幕截图。它有一些限制,我不太确定。但是,我相信可能有解决办法。
从这里您可以像这样截取两个组合图像视图的屏幕截图
private fun captureView(view: View, window: Window, bitmapCallback: (Bitmap)->Unit) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
// Above Android O, use PixelCopy
val bitmap = Bitmap.createBitmap(view.width, view.height, Bitmap.Config.ARGB_8888)
val location = IntArray(2)
view.getLocationInWindow(location)
PixelCopy.request(
window,
Rect(
location[0],
location[1],
location[0] + view.width,
location[1] + view.height
),
bitmap,
{
if (it == PixelCopy.SUCCESS) {
bitmapCallback.invoke(bitmap)
}
},
Handler(Looper.getMainLooper()) )
} else {
val tBitmap = Bitmap.createBitmap(
view.width, view.height, Bitmap.Config.RGB_565
)
val canvas = Canvas(tBitmap)
view.draw(canvas)
canvas.setBitmap(null)
bitmapCallback.invoke(tBitmap)
}
}
在 takePhoto() 函数中,您可以删除 imageCapture.takePicture
逻辑并将其替换为这个。
Handler(Looper.getMainLooper()).postDelayed({
captureView(binding.cameraWrapper, requireActivity().window) {
// your new bitmap with overlay is here and you can save it to file just like any other bitmaps.
}
}, 500)