android - 前置摄像头预览在三星galaxy s4 mini中延伸

Question

我们在自己的应用中实现了自定义相机功能。这在除了三星galaxy S4 mini之外的nexus4,5，samsung s3，s4等所有设备上都运行良好。问题是图像仅在前置摄像头中伸展，但它在该设备的后置摄像头中工作良好。

对于三星galaxy s4 mini，屏幕尺寸为540X960，支持预览尺寸为1280x720。宽高比也相同，但我们正面临图像拉伸问题。我尝试了很多，但我无法解决这个问题，特别是在三星galaxy s4 mini的前置摄像头。请任何人帮助我。

Code

int currentCameraId = Camera.CameraInfo.CAMERA_FACING_FRONT;
Camera camera = Camera.open(currentCameraId);
try {
      camera.setPreviewDisplay(surfaceHolder);
      Camera.Parameters parameters = camera.getParameters();
      parameters.setPictureFormat(PixelFormat.JPEG);
      parameters.set("orientation", "portrait");

      camera.setDisplayOrientation(90);
      parameters.setRotation(270);
      Display display = getWindowManager().getDefaultDisplay();
      int widthd = display.getWidth(); // deprecated
      int heightd = display.getHeight();

      List<Camera.Size> previewSizes = parameters.getSupportedPreviewSizes();

      List<Camera.Size> pictureSizes = parameters.getSupportedPictureSizes();

      Camera.Size mPreviewSize = getOptimalPreviewSize(previewSizes, widthd, heightd);

      Camera.Size mpicSize = getOptimalPreviewSize(pictureSizes, widthd, heightd);


      parameters.setPreviewSize(mPreviewSize.width,mPreviewSize.height);
      parameters.setPictureSize(mpicSize.width,mpicSize.height);
      camera.setParameters(parameters);
   } catch (IOException exception) {
       camera.release();
   }
   camera.startPreview();

请参阅以下代码以计算最佳尺寸。

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;

        int targetHeight = h;

        for (Camera.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);
            }
        }

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