Okay, I went through different posts and find out that depending on mobile manufacturers there can be a complications such as capture images get rotated, so you have to be aware of that. What I did was:
fun rotateBitmap(bitmap: Bitmap): Bitmap? {
val matrix = Matrix()
when (getImageOrientation(bitmap)) {
ExifInterface.ORIENTATION_NORMAL -> return bitmap
ExifInterface.ORIENTATION_FLIP_HORIZONTAL -> matrix.setScale(-1f, 1f)
ExifInterface.ORIENTATION_ROTATE_270 -> matrix.setRotate(-90f)
ExifInterface.ORIENTATION_ROTATE_180 -> matrix.setRotate(180f)
ExifInterface.ORIENTATION_ROTATE_90 -> matrix.setRotate(90f)
ExifInterface.ORIENTATION_FLIP_VERTICAL -> {
matrix.setRotate(180f)
matrix.postScale(-1f, 1f)
}
ExifInterface.ORIENTATION_TRANSPOSE -> {
matrix.setRotate(90f)
matrix.postScale(-1f, 1f)
}
ExifInterface.ORIENTATION_TRANSVERSE -> {
matrix.setRotate(-90f)
matrix.postScale(-1f, 1f)
}
else -> return bitmap
}
This worked. But then I noticed something really weird and that might be related with how I configured Camera X configuration.
With the same device I get differently rotated Bitmaps (well, this should not happen. If devices rotates image weirdly, it should rotate images in both modes - in ImageAnalysesUseCase and ImageCaptureUseCase).
So, why is this happening and how can I fix it?
Code implementation:
Binding camera X to life-cycle:
CameraX.bindToLifecycle(
this,
buildPreviewUseCase(),
buildImageAnalysisUseCase(),
buildImageCaptureUseCase()
)
Preview use case:
private fun buildPreviewUseCase(): Preview {
val previewConfig = PreviewConfig.Builder()
.setTargetAspectRatio(config.aspectRatio)
.setTargetResolution(config.resolution)
.setTargetRotation(Surface.ROTATION_0)
.setLensFacing(config.lensFacing)
.build()
return AutoFitPreviewBuilder.build(previewConfig, cameraTextureView)
}
Capture use case:
private fun buildImageCaptureUseCase(): ImageCapture {
val captureConfig = ImageCaptureConfig.Builder()
.setTargetAspectRatio(config.aspectRatio)
.setTargetRotation(Surface.ROTATION_0)
.setTargetResolution(config.resolution)
.setCaptureMode(config.captureMode)
.build()
val capture = ImageCapture(captureConfig)
manualModeTakePhotoButton.setOnClickListener {
capture.takePicture(object : ImageCapture.OnImageCapturedListener() {
override fun onCaptureSuccess(imageProxy: ImageProxy, rotationDegrees: Int) {
viewModel.onManualCameraModeAnalysis(imageProxy, rotationDegrees)
}
override fun onError(useCaseError: ImageCapture.UseCaseError?, message: String?, cause: Throwable?) {
//
}
})
}
return capture
}
Analysis use case:
private fun buildImageAnalysisUseCase(): ImageAnalysis {
val analysisConfig = ImageAnalysisConfig.Builder().apply {
val analyzerThread = HandlerThread("xAnalyzer").apply { start() }
analyzerHandler = Handler(analyzerThread.looper)
setCallbackHandler(analyzerHandler!!)
setTargetAspectRatio(config.aspectRatio)
setTargetRotation(Surface.ROTATION_0)
setTargetResolution(config.resolution)
setImageReaderMode(config.readerMode)
setImageQueueDepth(config.queueDepth)
}.build()
val analysis = ImageAnalysis(analysisConfig)
analysis.analyzer = ImageRecognitionAnalyzer(viewModel)
return analysis
}
AutoFitPreviewBuilder:
class AutoFitPreviewBuilder private constructor(config: PreviewConfig,
viewFinderRef: WeakReference<TextureView>) {
/** Public instance of preview use-case which can be used by consumers of this adapter */
val useCase: Preview
/** Internal variable used to keep track of the use-case's output rotation */
private var bufferRotation: Int = 0
/** Internal variable used to keep track of the view's rotation */
private var viewFinderRotation: Int? = null
/** Internal variable used to keep track of the use-case's output dimension */
private var bufferDimens: Size = Size(0, 0)
/** Internal variable used to keep track of the view's dimension */
private var viewFinderDimens: Size = Size(0, 0)
/** Internal variable used to keep track of the view's display */
private var viewFinderDisplay: Int = -1
/** Internal reference of the [DisplayManager] */
private lateinit var displayManager: DisplayManager
/**
* We need a display listener for orientation changes that do not trigger a configuration
* change, for example if we choose to override config change in manifest or for 180-degree
* orientation changes.
*/
private val displayListener = object : DisplayManager.DisplayListener {
override fun onDisplayAdded(displayId: Int) = Unit
override fun onDisplayRemoved(displayId: Int) = Unit
override fun onDisplayChanged(displayId: Int) {
val viewFinder = viewFinderRef.get() ?: return
if (displayId == viewFinderDisplay) {
val display = displayManager.getDisplay(displayId)
val rotation = getDisplaySurfaceRotation(display)
updateTransform(viewFinder, rotation, bufferDimens, viewFinderDimens)
}
}
}
init {
// Make sure that the view finder reference is valid
val viewFinder = viewFinderRef.get() ?:
throw IllegalArgumentException("Invalid reference to view finder used")
// Initialize the display and rotation from texture view information
viewFinderDisplay = viewFinder.display.displayId
viewFinderRotation = getDisplaySurfaceRotation(viewFinder.display) ?: 0
// Initialize public use-case with the given config
useCase = Preview(config)
// Every time the view finder is updated, recompute layout
useCase.onPreviewOutputUpdateListener = Preview.OnPreviewOutputUpdateListener {
val viewFinder =
viewFinderRef.get() ?: return@OnPreviewOutputUpdateListener
// To update the SurfaceTexture, we have to remove it and re-add it
val parent = viewFinder.parent as ViewGroup
parent.removeView(viewFinder)
parent.addView(viewFinder, 0)
viewFinder.surfaceTexture = it.surfaceTexture
bufferRotation = it.rotationDegrees
val rotation = getDisplaySurfaceRotation(viewFinder.display)
updateTransform(viewFinder, rotation, it.textureSize, viewFinderDimens)
}
// Every time the provided texture view changes, recompute layout
viewFinder.addOnLayoutChangeListener { view, left, top, right, bottom, _, _, _, _ ->
val viewFinder = view as TextureView
val newViewFinderDimens = Size(right - left, bottom - top)
val rotation = getDisplaySurfaceRotation(viewFinder.display)
updateTransform(viewFinder, rotation, bufferDimens, newViewFinderDimens)
}
// Every time the orientation of device changes, recompute layout
displayManager = viewFinder.context
.getSystemService(Context.DISPLAY_SERVICE) as DisplayManager
displayManager.registerDisplayListener(displayListener, null)
// Remove the display listeners when the view is detached to avoid
// holding a reference to the View outside of a Fragment.
// NOTE: Even though using a weak reference should take care of this,
// we still try to avoid unnecessary calls to the listener this way.
viewFinder.addOnAttachStateChangeListener(object : View.OnAttachStateChangeListener {
override fun onViewAttachedToWindow(view: View?) {
displayManager.registerDisplayListener(displayListener, null)
}
override fun onViewDetachedFromWindow(view: View?) {
displayManager.unregisterDisplayListener(displayListener)
}
})
}
/** Helper function that fits a camera preview into the given [TextureView] */
private fun updateTransform(textureView: TextureView?, rotation: Int?, newBufferDimens: Size,
newViewFinderDimens: Size) {
// This should not happen anyway, but now the linter knows
val textureView = textureView ?: return
if (rotation == viewFinderRotation &&
Objects.equals(newBufferDimens, bufferDimens) &&
Objects.equals(newViewFinderDimens, viewFinderDimens)) {
// Nothing has changed, no need to transform output again
return
}
if (rotation == null) {
// Invalid rotation - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
viewFinderRotation = rotation
}
if (newBufferDimens.width == 0 || newBufferDimens.height == 0) {
// Invalid buffer dimens - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
bufferDimens = newBufferDimens
}
if (newViewFinderDimens.width == 0 || newViewFinderDimens.height == 0) {
// Invalid view finder dimens - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
viewFinderDimens = newViewFinderDimens
}
val matrix = Matrix()
// Compute the center of the view finder
val centerX = viewFinderDimens.width / 2f
val centerY = viewFinderDimens.height / 2f
// Correct preview output to account for display rotation
matrix.postRotate(-viewFinderRotation!!.toFloat(), centerX, centerY)
// Buffers are rotated relative to the device's 'natural' orientation: swap width and height
val bufferRatio = bufferDimens.height / bufferDimens.width.toFloat()
val scaledWidth: Int
val scaledHeight: Int
// Match longest sides together -- i.e. apply center-crop transformation
if (viewFinderDimens.width > viewFinderDimens.height) {
scaledHeight = viewFinderDimens.width
scaledWidth = Math.round(viewFinderDimens.width * bufferRatio)
} else {
scaledHeight = viewFinderDimens.height
scaledWidth = Math.round(viewFinderDimens.height * bufferRatio)
}
// Compute the relative scale value
val xScale = scaledWidth / viewFinderDimens.width.toFloat()
val yScale = scaledHeight / viewFinderDimens.height.toFloat()
// Scale input buffers to fill the view finder
matrix.preScale(xScale, yScale, centerX, centerY)
// Finally, apply transformations to our TextureView
textureView.setTransform(matrix)
}
companion object {
/** Helper function that gets the rotation of a [Display] in degrees */
fun getDisplaySurfaceRotation(display: Display?) = when(display?.rotation) {
Surface.ROTATION_0 -> 0
Surface.ROTATION_90 -> 90
Surface.ROTATION_180 -> 180
Surface.ROTATION_270 -> 270
else -> null
}
/**
* Main entrypoint for users of this class: instantiates the adapter and returns an instance
* of [Preview] which automatically adjusts in size and rotation to compensate for
* config changes.
*/
fun build(config: PreviewConfig, viewFinder: TextureView) =
AutoFitPreviewBuilder(config, WeakReference(viewFinder)).useCase
}
}
If configuration is correct (it looks okay to me), then next idea was that maybe converting captured images objects to bitmap might be faulty. Below you can see implementation.
Capture mode uses this function:
fun imageProxyToBitmap(image: ImageProxy): Bitmap {
val buffer: ByteBuffer = image.planes[0].buffer
val bytes = ByteArray(buffer.remaining())
buffer.get(bytes)
return BitmapFactory.decodeByteArray(bytes, 0, bytes.size)
}
Analysis mode uses this function:
fun toBitmapFromImage(image: Image?): Bitmap? {
try {
if (image == null || image.planes[0] == null || image.planes[1] == null || image.planes[2] == null) {
return null
}
val yBuffer = image.planes[0].buffer
val uBuffer = image.planes[1].buffer
val vBuffer = image.planes[2].buffer
val ySize = yBuffer.remaining()
val uSize = uBuffer.remaining()
val vSize = vBuffer.remaining()
val nv21 = ByteArray(ySize + uSize + vSize)
/* U and V are swapped */
yBuffer.get(nv21, 0, ySize)
vBuffer.get(nv21, ySize, vSize)
uBuffer.get(nv21, ySize + vSize, uSize)
val yuvImage = YuvImage(nv21, ImageFormat.NV21, image.width, image.height, null)
val out = ByteArrayOutputStream()
yuvImage.compressToJpeg(Rect(0, 0, yuvImage.width, yuvImage.height), 50, out)
val imageBytes = out.toByteArray()
return BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.size)
} catch (e: IllegalStateException) {
Log.e("IllegalStateException", "#ImageUtils.toBitmapFromImage(): Can't read the image file.")
return null
}
}
So, weirdly, on few devices toBitmapFromImage() sometimes comes up upwards, but at the same time (same device) imageProxyToBitmap() returns image in correct rotation - it has to be the image to bitmap functions fault, right?Why is this happening (because capture mode returns image normally) and how to fix this?
