自定义相机预览已拉伸并模糊

Question

我正在使用自定义相机，但自定义相机的预览会拉伸并模糊，但点击图片图像显示正确后。请帮助我如何在每台设备上设置预览，这就是我的代码

class Preview extends ViewGroup implements SurfaceHolder.Callback {
private final String TAG = "Preview";

SurfaceView mSurfaceView;
public static SurfaceHolder mHolder;
Size mPreviewSize;
List<Size> mSupportedPreviewSizes;
Camera mCamera;

Preview(Context context, SurfaceView sv) {
    super(context);

    mSurfaceView = sv;

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

public void setCamera(Camera camera) {
    mCamera = camera;
    if (mCamera != null) {
        mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
        requestLayout();

        // get Camera parameters
        Camera.Parameters params = mCamera.getParameters();

        List<String> focusModes = params.getSupportedFocusModes();
        if (focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) {
            // set the focus mode
            params.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
            // set Camera parameters
            mCamera.setParameters(params);

        }
    }
}


@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    // We purposely disregard child measurements because act as a wrapper to a SurfaceView that
    // centers the camera preview instead of stretching it.
    int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
    int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);

    // we only allow landscape, if height > width - it means that we are in rotation animation. Swap width with height
    if (height > width) {
        width += height;
        height = width - height;
        width = width - height;
    }

    setMeasuredDimension(width, height);
    Log.v("Camera", width + "x" + height);

    if (mSupportedPreviewSizes == null && mCamera != null) {
        mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
    }
    if (mSupportedPreviewSizes != null) {
        mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
    }
}

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    if (changed && getChildCount() > 0) {
        final View child = getChildAt(0);

        final int width = r - l;
        final int height = b - t;

        int previewWidth = width;
        int previewHeight = height;
        if (mPreviewSize != null) {
            previewWidth = mPreviewSize.width;
            previewHeight = mPreviewSize.height;
        }

        // Center the child SurfaceView within the parent.
        if (width * previewHeight > height * previewWidth) {
            final int scaledChildWidth = previewWidth * height / previewHeight;
            child.layout((width - scaledChildWidth) / 2, 0,
                    (width + scaledChildWidth) / 2, height);
        } else {
            final int scaledChildHeight = previewHeight * width / previewWidth;
            child.layout(0, (height - scaledChildHeight) / 2,
                    width, (height + scaledChildHeight) / 2);
        }
    }
}

public void surfaceCreated(SurfaceHolder holder) {
    // The Surface has been created, acquire the camera and tell it where
    //  to draw.

    try {
        if (mCamera != null) {
            mCamera.setPreviewDisplay(holder);


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

public void surfaceDestroyed(SurfaceHolder holder) {
    // Surface will be destroyed when we return, so stop the preview.
    if (mCamera != null) {
        mCamera.stopPreview();
    }
}


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

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

    int targetHeight = h;

    // Try to find an size match aspect ratio and size
    for (Size size : sizes) {
        double ratio = (double) size.width / size.height;
        if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
        if (Math.abs(size.height - targetHeight) < minDiff) {
            optimalSize = size;
            minDiff = Math.abs(size.height - targetHeight);
        }
    }

    // Cannot find the one match the aspect ratio, ignore the requirement
    if (optimalSize == null) {
        minDiff = Double.MAX_VALUE;
        for (Size size : sizes) {
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }
    }
    return optimalSize;
}

public void refreshCamera(Camera camera) {
    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
    setCamera(camera);
    try {
        mCamera.setDisplayOrientation(90);
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();
    } catch (Exception e) {
        Log.d(VIEW_LOG_TAG, "Error starting camera preview: " + e.getMessage());
    }
}

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


        Camera.Parameters parameters = mCamera.getParameters();
        // List<Camera.Size> previewSizes = parameters.getSupportedPreviewSizes();
        //Camera.Size previewSize = previewSizes.get(4); //480h x 720w
        parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
        parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();


    } catch (Exception e) {
        e.printStackTrace();
    }
}
}

点击图片后显示正确