如何在android studio中修复CameraSource预览方向答案

【问题标题】：how to fix CameraSource preview orientation in android studio如何在android studio中修复CameraSource预览方向
【发布时间】：2021-09-04 09:46:44
【问题描述】：

所以我在我的应用程序中使用CameraSource 来预览相机扫描，但问题是相机预览总是水平的。为了更清楚地看这张照片： Preview

我的意思是预览总是倾斜的。如何使相机扫描预览向上（正常）？
这是我当前的代码：

private fun setupCameraSource() {
        cameraSource = CameraSource.Builder(activity, cameraSourceCustomDetector)
            .setAutoFocusEnabled(true).setRequestedFps(10F)
            .setFacing(CameraSource.CAMERA_FACING_BACK).build()
    }

或者如果整个代码有帮助，我不知道我是否做错了。

class colorDetector(activity: Activity, cameraPreview: ImageView?, editCameraPreview: ImageView?) {

    private val TAG = "colorDetector"
    private var  bitmap:Bitmap? = null
    private val FPS: Number = 20

    private var cameraSource: CameraSource? = null
    private var cameraSourceCustomDetector: CustomDetector? = null
    private var editCameraPreview: ImageView? = null
    //private var visionUtilities: VisionUtilities? = null
    private var activity: Activity? = null
    private var cameraPreview: ImageView? = null

    init {
        this.activity = activity
        this.cameraPreview = cameraPreview
        this.editCameraPreview = editCameraPreview
        cameraSourceCustomDetector = CustomDetector()
        setupCameraSource()
    }

    private fun setupCameraSource() {
        cameraSource = CameraSource.Builder(activity, cameraSourceCustomDetector)
            .setAutoFocusEnabled(true).setRequestedFps(10F)
            .setFacing(CameraSource.CAMERA_FACING_BACK).build()
    }

    fun start(context: Context) {
        try {
            if (ActivityCompat.checkSelfPermission(context, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
                cameraSource?.start()
            }
        } catch (e: IOException) {
            Log.d(TAG, "Couldn't start camera")
        }
    }

    fun stop() {
        cameraSource!!.stop()
    }

    fun saveImageToStorage() {
        saveImgInStorage(bitmap!!,activity!!)
    }
    fun uploadImageToFirebase(type: uploadType) {
        uploadPictureToFirebaseStorage(activity!!,bitmap,null,type)
    }
    inner class CustomDetector : Detector<Point>() {

        @RequiresApi(Build.VERSION_CODES.O)
        override fun detect(frame: Frame?): SparseArray<Point>? {

            val byteBuffer: ByteBuffer = frame!!.grayscaleImageData
            val bytes: ByteArray = byteBuffer.array()
            val w = frame.metadata.width
            val h = frame.metadata.height
            val yuvimage = YuvImage(bytes, ImageFormat.NV21, w, h, null)
            val baos = ByteArrayOutputStream()
            yuvimage.compressToJpeg(
                Rect(0, 0, w, h),
                100,
                baos
            ) // Where 100 is the quality of the generated jpeg

            val jpegArray = baos.toByteArray()
             bitmap = BitmapFactory.decodeByteArray(jpegArray, 0, jpegArray.size)
            activity?.runOnUiThread(Runnable{ getEditedImg(bitmap!!,w,h, cameraPreview!!, editCameraPreview!!,
                activity!!
            ) })

            return null

        }


    }
}

【问题讨论】：

标签： android-studio kotlin camera android-camera

【解决方案1】：

好吧，最后经过很长时间的搜索，我决定这样做，我不确定这是否是理想的方式，但如果有人想要，这是我所做的解决方案：

我创建了一个名为 rotate 的函数：

// rotates a 'bitmap' clockwise direction by 'degree'
fun rotate(bitmap: Bitmap, degree: Float): Bitmap? {
        val matrix = Matrix()
        matrix.postRotate(degree)
        val resizedBitmap = Bitmap.createScaledBitmap(bitmap, bitmap.width, bitmap.width, false)
        return Bitmap.createBitmap(resizedBitmap, 0, 0, resizedBitmap.width, resizedBitmap.height, matrix, true)
}

并用rotate(bitmap, 90F)替换了bitmap的3个地方。

【讨论】：