将捕获的图像转换为位图

Question

我正在使用 Java 探索 android 的 CameraX API 并尝试构建捕获图像用例。这是

的代码

private void takePicture() {
        imageCapture.takePicture(new ImageCapture.OnImageCapturedListener() {
            @Override
            public void onCaptureSuccess(ImageProxy image, int rotationDegrees) {
                Bitmap bitmap = rotateImage(toBitmap(image.getImage()), (float) rotationDegrees);
                ImageView takenImage.setImageBitmap(bitmap);
                super.onCaptureSuccess(image, rotationDegrees);
            }
        });
    }

并将捕获的图像转换为位图。我正在尝试在 Java 中编写的以下问题中实现@Ahwar 的回答：这是那里给出的代码答案：

private Bitmap toBitmap(Image image) {
        Image.Plane[] planes = image.getPlanes();
        ByteBuffer yBuffer = planes[0].getBuffer();
        ByteBuffer uBuffer = planes[1].getBuffer();
        ByteBuffer vBuffer = planes[2].getBuffer();

        int ySize = yBuffer.remaining();
        int uSize = uBuffer.remaining();
        int vSize = vBuffer.remaining();

        byte[] nv21 = new byte[ySize + uSize + vSize];
        //U and V are swapped
        yBuffer.get(nv21, 0, ySize);
        vBuffer.get(nv21, ySize, vSize);
        uBuffer.get(nv21, ySize + vSize, uSize);

        YuvImage yuvImage = new YuvImage(nv21, ImageFormat.NV21, image.getWidth(), image.getHeight(), null);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        yuvImage.compressToJpeg(new Rect(0, 0, yuvImage.getWidth(), yuvImage.getHeight()), 75, out);

        byte[] imageBytes = out.toByteArray();
        return BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.length);
    }

我的问题：当我调用 toBitmap(image) 函数时，我得到 ArrayIndexOutOfBoundsException，调试后，我了解到图像平面的大小是 只是 1 而不是比 3。我附上了这里收到的异常，

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.camerax3, PID: 17342
    java.lang.ArrayIndexOutOfBoundsException: length=1; index=1
        at com.example.camerax3.activity.MainActivity.toBitmap(MainActivity.java:210)
        at com.example.camerax3.activity.MainActivity.access0(MainActivity.java:45)
        at com.example.camerax3.activity.MainActivity.onCaptureSuccess(MainActivity.java:239)
        at androidx.camera.core.ImageCapture$ImageCaptureRequest.dispatchImage(ImageCapture.java:1341)
        at androidx.camera.core.ImageCapture.onImageAvailable(ImageCapture.java:657)
        at androidx.camera.core.MetadataImageReader.run(MetadataImageReader.java:279)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7099)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:494)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:965)

谁能提出解决这个问题的方法？。我在 Kotlin 中阅读了很多答案，但我试图在 Java 中实现相同的答案。在 java 中将图像转换为位图的任何替代方法也值得赞赏。

Answer 1

这段代码对我有用，试试吧。

  private Bitmap getBitmap(ImageProxy image) {
        ByteBuffer buffer = image.getPlanes()[0].getBuffer();
        buffer.rewind();
        byte[] bytes = new byte[buffer.capacity()];
        buffer.get(bytes);
        byte[] clonedBytes = bytes.clone();
        return BitmapFactory.decodeByteArray(clonedBytes, 0, clonedBytes.length);
    }

Answer 2

使用此扩展从 ImageProxy

获取位图

在科特林中：

fun Image.toBitmap(): Bitmap {
    val buffer = planes[0].buffer
    buffer.rewind()
    val bytes = ByteArray(buffer.capacity())
    buffer.get(bytes)
    return BitmapFactory.decodeByteArray(bytes, 0, bytes.size)
}

在 Kotlin 中这样设置：

imageView.setImageBitmap(image.image?.toBitmap())

并在 Java 中这样设置：

imageView.setImageBitmap(YourExtensionHelper.toBitmap(image.getImage()));

将捕获的图像转换为位图

Converting a captured image to a Bitmap

java

android

indexoutofboundsexception

android-bitmap

android-camerax