c++ - 图像 C++ 上有太多黑色区域的 OpenCV 校正

Question

我正在使用 OpenCV 校准和校正立体声系统。我有一个眼睛会聚的立体相机，实际上我按以下顺序运行这些功能:

for(int j=0; j < ChessBoard.numSquares; j++)
    obj.push_back(Point3f((j/ChessBoard.numCornersHor)*ChessBoard.squareDim, (j%ChessBoard.numCornersHor)*ChessBoard.squareDim, 0.0f));
[...]

然后我循环它以获得我想要获取的图像数量

found_L = findChessboardCorners(image_L, ChessBoard.board_sz, corners_L, CALIB_CB_ADAPTIVE_THRESH + CALIB_CB_NORMALIZE_IMAGE + CV_CALIB_CB_FILTER_QUADS + CALIB_CB_FAST_CHECK);
found_R= findChessboardCorners(image_R, ChessBoard.board_sz, corners_R, CALIB_CB_ADAPTIVE_THRESH + CALIB_CB_NORMALIZE_IMAGE + CV_CALIB_CB_FILTER_QUADS + CALIB_CB_FAST_CHECK);
found = found_L && found_R;
if(found)
  { 
    cornerSubPix(image_L, corners_L, Size(11, 11), Size(-1, -1), TermCriteria(CV_TERMCRIT_EPS + CV_TERMCRIT_ITER, 30, 0.1));
    cornerSubPix(image_R, corners_R, Size(11, 11), Size(-1, -1), TermCriteria(CV_TERMCRIT_EPS + CV_TERMCRIT_ITER, 30, 0.1));
    drawChessboardCorners(image_L, ChessBoard.board_sz, corners_L, found);
    drawChessboardCorners(image_R, ChessBoard.board_sz, corners_R, found);

    image_points[0].push_back(corners_L);
    image_points[1].push_back(corners_R);
    object_points.push_back(obj);
    printf("Right: coordinates stored\n");
    printf("Left: coordinates stored\n");
  }

在这个 block 之后我称之为两个:

cameraMatrix[0] = Mat::eye(3, 3, CV_64F);
cameraMatrix[1] = Mat::eye(3, 3, CV_64F);

calibrateCamera(object_points, image_points[0], imageSize, cameraMatrix[0], distCoeffs[0], rvecs_L, tvecs_L);

calibrateCamera(object_points, image_points[1], imageSize, cameraMatrix[1], distCoeffs[1], rvecs_R, tvecs_R);

然后:

rms = stereoCalibrate(object_points, image_points[0], image_points[1],
                    cameraMatrix[0], distCoeffs[0],
                    cameraMatrix[1], distCoeffs[1],
                    imageSize, R, T, E, F,
                    TermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 100, 1e-5),
                    CV_CALIB_FIX_ASPECT_RATIO+CV_CALIB_FIX_INTRINSIC);

最后:

stereoRectify(cameraMatrix[0], distCoeffs[0],
                  cameraMatrix[1], distCoeffs[1],
                  imageSize, R, T, R1, R2, P1, P2, Q,
                  CALIB_ZERO_DISPARITY, -1, imageSize, &roi1, &roi2 );

initUndistortRectifyMap(cameraMatrix[0], distCoeffs[0], R1, P1, imageSize, CV_16SC2, map11, map12);
initUndistortRectifyMap(cameraMatrix[1], distCoeffs[1], R2, P2, imageSize, CV_16SC2, map21, map22);
remap(imgL, imgL, map11, map12, INTER_LINEAR,BORDER_CONSTANT, Scalar());
remap(imgR, imgR, map21, map22, INTER_LINEAR,BORDER_CONSTANT, Scalar());

这基本上就是我正在做的，但结果真的很糟糕，因为图像有很大的黑色区域。这是一个例子:

这是我必须获得的校正图像，它是直接从相机拍摄的:

正如你所看到的，图像似乎是在右侧平移并剪切的，与右侧相同，但在左侧平移，结果几乎相同。

那么我怎样才能获得与上一个相似的更好的结果呢？哪里有问题？作为附加数据，我注意到 rms 不是很好，大约 0.4，重新投影误差大约是 0.2，我知道它们必须低一点，但我已经尝试了很多次不同的模式、照明和等等，在校准中，但我总是得到相同的结果甚至最差。

Answer 1

尝试像这样调用 stereoRectify:

stereoRectify(cameraMatrix[0], distCoeffs[0],
              cameraMatrix[1], distCoeffs[1],
              imageSize, R, T, R1, R2, P1, P2, Q,
              0, -1, imageSize, &roi1, &roi2 );

即使用 0 而不是标志 CALIB_ZERO_DISPARITY。

此外，为了改进 stereoCalibrate 获得的 RMS，尝试使用标记 CV_CALIB_USE_INTRINSIC_GUESS(参见 this related answer):

rms = stereoCalibrate(object_points, image_points[0], image_points[1],
                cameraMatrix[0], distCoeffs[0],
                cameraMatrix[1], distCoeffs[1],
                imageSize, R, T, E, F,
                TermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS, 100, 1e-5),
                CV_CALIB_USE_INTRINSIC_GUESS+
                    CV_CALIB_FIX_ASPECT_RATIO+CV_CALIB_FIX_INTRINSIC);