Refind not detected markers based on the already detected and the board layout

[detectedCorners, detectedIds, rejectedCorners] = cv.refineDetectedMarkers(img, board, detectedCorners, detectedIds, rejectedCorners)
[detectedCorners, detectedIds, rejectedCorners, recoveredIdxs] = cv.refineDetectedMarkers(...)
[...] = cv.refineDetectedMarkers(..., 'OptionName',optionValue, ...)

Input

• img input image (8-bit grayscale or color).
• board layout of markers in the board.
• detectedCorners cell array of already detected marker corners {{[x,y],..}, ..}.
• detectedIds vector of already detected marker identifiers (0-based).
• rejectedCorners cell array of rejected candidates during the marker detection process {{[x,y],..}, ..}.

Output

• detectedCorners output refined marker corners.
• detectedIds output refined marker identifiers
• rejectedCorners output refined rejected corners.
• recoveredIdxs Optional array that returns the indexes of the recovered candidates in the original rejectedCorners array.

Options

• CameraMatrix optional input 3x3 floating-point camera matrix A = [fx 0 cx; 0 fy cy; 0 0 1].
• DistCoeffs optional vector of distortion coefficients [k1,k2,p1,p2,k3,k4,k5,k6,s1,s2,s3,s4] of 4, 5, 8 or 12 elements.
• MinRepDistance minimum distance between the corners of the rejected candidate and the reprojected marker in order to consider it as a correspondence. default 10.0
• ErrorCorrectionRate rate of allowed erroneous bits respect to the error correction capability of the used dictionary. -1 ignores the error correction step. default 3.0
• CheckAllOrders Consider the four posible corner orders in the rejectedCorners array. If it set to false, only the provided corner order is considered (default true).
• DetectorParameters marker detection parameters.

This function tries to find markers that were not detected in the basic cv.detectMarkers function. First, based on the current detected marker and the board layout, the function interpolates the position of the missing markers. Then it tries to find correspondence between the reprojected markers and the rejected candidates based on the minRepDistance and errorCorrectionRate parameters. If camera parameters and distortion coefficients are provided, missing markers are reprojected using cv.projectPoints function. If not, missing marker projections are interpolated using global homography, and all the marker corners in the board must have the same Z coordinate.