Question

我在我的应用程序上使用自定义相机预览，几乎在所有设备上都可以正常工作，因为HTC-One我得到了不好的剪辑，原始照片与之不相符预览显示在顶部。

它只发生在这个设备上，这是我的预览相机的代码和关于发生了什么的图片。

提前感谢有人给我的任何帮助。

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

private final String TAG = "CameraPreview";

private SurfaceHolder mHolder;
private Camera mCamera;
private Context context;
private Camera.Size mPreviewSize;
private List<Camera.Size> mSupportedPreviewSizes;

public CameraPreview(Context context) {
    super(context);
    this.context = context;
    mHolder = getHolder();
    mHolder.addCallback(this);
}

public void setCamera(Camera camera) {
    mCamera = camera;
    if (mCamera != null) {

        mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
        for (Camera.Size str : mSupportedPreviewSizes) {
            Log.e(TAG, str.width + "/" + str.height);
        }

        mHolder = getHolder();
        mHolder.addCallback(this);
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
    final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);

    if (mSupportedPreviewSizes != null) {
        mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
    }

    float ratio;
    if (mPreviewSize.height >= mPreviewSize.width) {
        ratio = (float) mPreviewSize.height / (float) mPreviewSize.width;
    } else {
        ratio = (float) mPreviewSize.width / (float) mPreviewSize.height;
    }

    setMeasuredDimension(width, (int) (width * ratio));
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {

    if (mHolder.getSurface() == null) {
        // preview surface does not exist
        return;
    }

    // stop preview before making changes
    try {
        mCamera.stopPreview();
    } catch (Exception e) {
        // ignore: tried to stop a non-existent preview
    }

    // set preview size and make any resize, rotate or reformatting changes here
    // start preview with new settings
    try {
        Camera.Parameters parameters = mCamera.getParameters();
        parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
        parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);

        mCamera.setParameters(parameters);
        mCamera.setDisplayOrientation(90);
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();

    } catch (Exception e) {
        Log.d(TAG, "Error starting camera preview: " + e.getMessage());
    }
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}

public void setFlash(String flashMode) {
    Camera.Parameters params = mCamera.getParameters();
    params.setFlashMode(flashMode);
    mCamera.setParameters(params);
}

private Camera.Size getOptimalPreviewSize(List<Camera.Size> sizes, int w, int h) {
    final double ASPECT_TOLERANCE = 0.1;
    double targetRatio = (double) h / w;

    if (sizes == null) {
        return null;
    }

    Camera.Size optimalSize = null;
    double minDiff = Double.MAX_VALUE;


    for (Camera.Size size : sizes) {
        double ratio = (double) size.height / size.width;
        if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE)
            continue;

        if (Math.abs(size.height - h) < minDiff) {
            optimalSize = size;
            minDiff = Math.abs(size.height - h);
        }
    }

    if (optimalSize == null) {
        minDiff = Double.MAX_VALUE;
        for (Camera.Size size : sizes) {
            if (Math.abs(size.height - h) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - h);
            }
        }
    }

    return optimalSize;
}

public void switchCamera(Camera camera) {
    Display display = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
    if (display.getRotation() == Surface.ROTATION_0) {
        camera.setDisplayOrientation(90);
    } else if (display.getRotation() == Surface.ROTATION_270) {
        camera.setDisplayOrientation(180);
    }

    setCamera(camera);
    try {
        camera.setPreviewDisplay(mHolder);
    } catch (IOException exception) {
        Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
    }
}
}

enter image description here

Answer 1

相机预览大小和图片大小是两个不同的参数，您可以通过setPictureSize（）和setPreviewSize（）API更新这些参数。但是，如果用户不更改这些大小，它将使用默认值。

在这种情况下，您将通过根据某个宽高比计算最佳预览大小来更新预览大小。但您没有更新图片大小，因此它将使用默认图片大小。

如果图片尺寸和预览尺寸宽高比不同，则拍摄的图像肯定与预览不同。因此，通过计算具有与预览尺寸相同的宽高比的最佳图片尺寸来更新图片尺寸。

预览相机HTC-One剪切图像

1 个答案: