ative. exponent_focal_length_x[i] specifies the exponent part of the focal length of the i-th camera in the horizontal direction. The value ofexponent_focal_length_x[i]: shall be in the range of 0 to 62, inclusive. The value 63 is reserved for future use by ITU-T ISO/IEC. Decoders shall treat the value 63 as indicating an unspecified focal length. nantissa_focal_length_x[i] specifies the mantissa part of the focal length of the i-th camera in the horizontal direction. The length of the mantissa_focal_length_x[i syntax element is variable and determined as follows: If exponent_focal_length_x[i]==0,t = the length is Max( 0, prec_focal_length - 30). Otherwise (0 exponent_focal_length_x[i] 63), the length is Max( 0, exponent_focal_length_x[i]+ prec_focal_length - 31 ). sign_focal_length_y[i] equal to 0 indicates that the sign of the focal length of the i-th camera in the vertical direction is positive.sign_focal_length_y[ equal to 1 indicates that the sign is negative. exponent_focal_length_y[i]: specifies the exponent part of the focal length of the i-th camera in the vertical direction. The value of `exponent_focal_length_ y| shall be in the range of 0 to 62, inclusive. The value 63 is reserved for future use by ITU-T ISO/IEC. Decoders shall treat the value 63 as indicating an unspecified focal length. mantissa_focal_length_y[i] specifies the mantissa part of the focal length of the i-th camera in the vertical direction. The length of the mantissa_focal_length_y[ i ] syntax element is variable and determined as follows: If exponent_focal_length_y[i]= = = 0, the length is Max( 0, prec_focal_length - 30). Otherwise (0 < exponent_focal_length_y[i] 63), the length is Max( 0, exponent_focal_length_y[i]+ prec_focal_length - 31 ). sign_principal_point_x[i] equal to 0 indicates that the sign of the principal point of the i-th camera in the horizontal direction is positive. sign_principal_point_x[i equal to 1 indicates that the sign is negative. xponent_principal_point_x[i] specifies the exponent part of the principal point