/// If it is on, then this check is performed before the main algorithm and if a chessboard is not found, the function returns 0 instead of wasting 0.3-1s on doing the full search.
/// </summary>
FastCheck=8,
/// <summary>
/// Run an exhaustive search to improve detection rate.
/// </summary>
Exhaustive=16,
/// <summary>
/// Up sample input image to improve sub-pixel accuracy due to aliasing effects. This should be used if an accurate camera calibration is required.
/// Finds the positions of internal corners of the chessboard using a sector based approach.
/// </summary>
/// <param name="image">Source chessboard view. It must be an 8-bit grayscale or color image.</param>
/// <param name="patternSize">Number of inner corners per a chessboard row and column ( patternSize = cv::Size(points_per_row,points_per_colum) = cv::Size(columns,rows) ).</param>
/// <param name="corners">Output array of detected corners.</param>
/// Draws the individual chessboard corners detected (as red circles) in case if the board was not found (pattern_was_found=0) or the colored corners connected with lines when the board was found (pattern_was_found != 0).