Android CameraX：设备方向切换中的图像分辨率与方向处理实践

<activity
    android:name=".MainActivity"
    android:exported="true"
    android:screenOrientation="portrait"
    tools:ignore="LockedOrientationActivity">
</activity>

private void bindCamera(@NonNull ProcessCameraProvider cameraProvider) {
    Log.d(TAG, "Binding camera");
    CameraSelector cameraSelector = new CameraSelector.Builder()
            .requireLensFacing(CameraSelector.LENS_FACING_BACK)
            .build();

    // Image analysis settings
    ImageAnalysis.Builder imageAnalysisBuilder = new ImageAnalysis.Builder();

    ImageAnalysis imageAnalysis = imageAnalysisBuilder
            .setImageQueueDepth(1)
            .setTargetResolution(new Size(720, 1280)) // 调整为竖屏模式的宽度和高度
            .setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST)
            .build();

    imageAnalysis.setAnalyzer(analyzerExecutor, imageAnalyzer);

    var captureBuilder = new ImageCapture.Builder();
    captureBuilder.setTargetRotation(Surface.ROTATION_0). // 对于竖屏，通常设置为Surface.ROTATION_0或由系统自动决定
            setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY).
            setTargetResolution(new Size(3024, 4032)). // 调整为竖屏模式的宽度和高度 (例如，从4032x3024变为3024x4032)
            setJpegQuality(Constants.JPEG_QUALITY).
            setFlashMode(ImageCapture.FLASH_MODE_OFF);

    // ... 其他 ImageCapture 配置 ...

    imageCapture = captureBuilder.build();

    try {
        cameraProvider.unbindAll();
        if (lifecycleOwner.getLifecycle().getCurrentState() != DESTROYED) {
            this.camera = cameraProvider.bindToLifecycle(lifecycleOwner,
                    cameraSelector,
                    imageCapture,
                    imageAnalysis);
        }
    } catch (Exception e) {
        Log.e(TAG, "Camera binding failed", e);
        MainActivity.instance.snackbar.showError("Camera binding failed", e);
    }
}

public class MyImageAnalyzer implements ImageAnalysis.Analyzer {

    @Override
    public void analyze(@NonNull ImageProxy imageProxy) {
        // 获取需要应用的旋转角度
        int rotationDegrees = imageProxy.getImageInfo().getRotationDegrees();

        // 获取图像数据 (例如，YUV_420_888 格式)
        // Image image = imageProxy.getImage();

        // 在这里处理图像数据，并应用 rotationDegrees
        // 例如，将YUV数据转换为Bitmap并旋转：
        // Bitmap bitmap = yuvToBitmap(image); // 假设有这个转换方法
        // Matrix matrix = new Matrix();
        // matrix.postRotate(rotationDegrees);
        // Bitmap rotatedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);

        // 处理 rotatedBitmap...

        imageProxy.close(); // 非常重要：处理完后关闭ImageProxy
    }

    // 示例：YUV_420_888 转 Bitmap 并旋转的简化逻辑
    // 实际生产环境需要更健壮的YUV转RGB/Bitmap实现
    private Bitmap yuvToBitmap(Image image, int rotationDegrees) {
        // ... (复杂的YUV转RGB逻辑，此处省略) ...
        // 假设我们已经得到了一个原始的Bitmap
        Bitmap originalBitmap = ...; 

        if (rotationDegrees != 0) {
            Matrix matrix = new Matrix();
            matrix.postRotate(rotationDegrees);
            return Bitmap.createBitmap(originalBitmap, 0, 0, originalBitmap.getWidth(), originalBitmap.getHeight(), matrix, true);
        } else {
            return originalBitmap;
        }
    }
}