def find_first_peak(corr):
    """
    Find row and column indices of the first correlation peak.

    Parameters
    ----------
    corr : np.ndarray
        the correlation map

    Returns
    -------
    i : int
        the row index of the correlation peak

    j : int
        the column index of the correlation peak

    corr_max1 : int
        the value of the correlation peak

    """
    ind = corr.argmax()
    s = corr.shape[1]
    i = ind // s
    j = ind % s
    return i, j, corr.max()
