使用Camera2 API Kotlin单击图像时的白色图像

Question

我们在代码中使用Camera2 API进行图像捕获，每当我们在闪光灯模式打开的情况下捕获图像时，我们都会在三星设备中获得白色图像。

以下是拍摄照片的代码剪辑：

private val captureCallback = object : CameraCaptureSession.CaptureCallback() {
override fun onCaptureCompleted(
session: CameraCaptureSession,
request: CaptureRequest,
result: TotalCaptureResult
) {
if (result != null) {
process(result)
}
}
private fun process(result: CaptureResult) {
try {
if (locked) return
/* Wait for all states to be ready, if they are not ready repeat basic capture while camera is preparing for capture */
if (result.isLocked() || captureTimes > MAX_CAPTURE_TIMES) {
/* Take picture */
locked = true
capture()
} else {
/* Wait while camera is preparing */
captureTimes++
session?.capture(sessionBuilder?.build()!!, this, AsyncUtils.backgroundHandler)
}
} catch (t: Throwable) {
pictureCallback?.onError(t)
}
}
private fun capture() {
cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE).apply {
copyParamsFrom(sessionBuilder)
/* Set picture quality */
set(CaptureRequest.JPEG_QUALITY, config.pictureQuality.toByte())
set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER, CameraMetadata.CONTROL_AE_PRECAPTURE_TRIGGER_START)
/* Add surface target that will receive capture */
addTarget(imageReader?.surface!!)
session?.apply {
/* Freeze preview session */
abortCaptures()
stopRepeating()
/* Take dat picture */
capture(build(), null, AsyncUtils.backgroundHandler)
}
}
}
}

我们使用Camera2 API在我们的代码中进行图像捕获，每当我们在闪光灯模式打开的情况下捕获图像时，我们都会在三星设备中获得白色图像。

以下是拍摄照片的代码剪辑：

private val stateCallback = object : CameraCaptureSession.StateCallback() {
override fun onConfigured(cameraCaptureSession: CameraCaptureSession) {
session = cameraCaptureSession
try {
sessionBuilder =
cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW).apply {
applyConfig(config)
addTarget(surface!!)
}
startSession()
initCallback?.onActive()
initCallback = null
} catch (t: Throwable) {
initCallback?.onError(t)
initCallback = null
}
}
override fun onConfigureFailed(cameraCaptureSession: CameraCaptureSession) {
initCallback?.onError(CameraConfigurationFailedException)
initCallback = null
}
}
fun createInitialPreviewSession(textureView: TextureView, callback: InitCallback) {
this.initCallback = callback
createSession(textureView)
}
override fun createSession(textureView: TextureView) {
try {
initTextureViewSurface(textureView)
initImageReader()
cameraDevice.createCaptureSession(
listOf(surface, imageReader?.surface),
stateCallback,
AsyncUtils.backgroundHandler
)
} catch (t: Throwable) {
initCallback?.onError(t)
initCallback = null
}
}

我们使用Camera2 API在我们的代码中进行图像捕获，每当我们在闪光灯模式打开的情况下捕获图像时，我们都会在三星设备中获得白色图像。

以下是拍摄照片的代码剪辑：

private fun initImageReader() {
this.imageReader = ImageReader.newInstance(
config.pictureSize.width,
config.pictureSize.height,
ImageFormat.JPEG,
2
)
imageReader?.setOnImageAvailableListener({ reader ->
async(
task = {
val image = reader.acquireLatestImage()
val bitmap = image.toBitmap()
image.close()
if (bitmap != null) {
val orientationDifference =
CameraUtils.calculateDisplayOrientation(activity, config).toFloat()
pictureTransformation?.transform(bitmap, config, orientationDifference)
?: bitmap
} else {
null
}
},
onResult = {
locked = false
unlockFocus(config.focusMode)
if (it != null) {
pictureCallback?.onPictureTaken(it)
} else {
pictureCallback?.onError(PictureConversionException)
}
}
)
}, AsyncUtils.backgroundHandler)
}
fun takePicture(callback: PictureCallback) {
captureTimes = 0
this.pictureCallback = callback
sessionBuilder?.apply {
/* Trigger AF and AE */
if (config.focusMode in arrayOf(
FocusMode.AUTO,
FocusMode.CONTINUOUS_PICTURE,
FocusMode.CONTINUOUS_VIDEO
)
) {
set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE)
focusCenterIfUnfocused()
}
if (config.isHardwareAtLeastLimited()) {
set(
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER,
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START
)
}
session?.capture(build(), captureCallback, AsyncUtils.backgroundHandler)
if (config.isHardwareAtLeastLimited()) {
set(
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER,
CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_IDLE
)
}
}
}
private fun focusCenterIfUnfocused() {
if (isFocused()) return
val activeRect =
config.characteristics?.get(CameraCharacteristics.SENSOR_INFO_ACTIVE_ARRAY_SIZE)
?: return
val centerX = activeRect.width() / 2
val centerY = activeRect.height() / 2
val offsetX = (activeRect.width() * 0.1f).toInt()
val offsetY = (activeRect.height() * 0.1f).toInt()
val centerRegion = Rect(
max(centerX - offsetX, 0),
max(centerY - offsetY, 0),
min(centerX + offsetX, activeRect.width()),
min(centerY + offsetY, activeRect.height())
)
sessionBuilder?.set(
CaptureRequest.CONTROL_AF_REGIONS,
arrayOf(MeteringRectangle(centerRegion, MeteringRectangle.METERING_WEIGHT_MAX - 1))
)
}
private fun isFocused(): Boolean {
val regions = sessionBuilder?.get(CaptureRequest.CONTROL_AF_REGIONS)
val focusedRegion = regions?.getOrNull(0)
return focusedRegion?.meteringWeight == MeteringRectangle.METERING_WEIGHT_MAX - 1
}
override fun release() {
super.release()
surface = null
pictureCallback = null
initCallback = null
try {
imageReader?.close()
} catch (t: Throwable) {
} finally {
imageReader = null
}
}

Answer 1

您有三个不同的代码片段，它们似乎根本不在一起。

但是看看https://github.com/googlearchive/android-Camera2Basic/blob/master/Application/src/main/java/com/example/android/camera2basic/Camera2BasicFragment.java以获取闪光捕获的样本。