Orthority RPC parametersΒΆ

This is the native Orthority format for RPC camera parameters. It is a YAML file containing a nested dictionary of one or more image filename keys and the corresponding RPC parameter dictionary values. The basic layout is:

image filename 1:
    # camera 1 parameters:
    name 1: value 1
    # ...
    name N: value N
# ...
image filename N:
    # camera N parameters:
    name 1: value 1
    # ...
    name N: value N

Root parameter names and value descriptions are:

Name

Value

im_size

Image [width, height] in pixels.

rpc

RPC parameters names and values as a dictionary.

Nested rpc parameter names and value descriptions are the same as the GeoTIFF definition:

Name

Value

lat_off

Geodetic latitude offset (degrees).

lat_scale

Geodetic latitude scale (unitless).

long_off

Geodetic longitude offset (degrees).

long_scale

Geodetic longitude scale (unitless).

height_off

Geodetic height offset (meters).

height_scale

Geodetic height scale (unitless).

line_off

Line / row offset (pixels).

line_scale

Line / row scale (unitless).

samp_off

Sample / column offset (pixels).

samp_scale

Sample / column scale (unitless).

line_num_coeff

Line / row numerator polynomial coefficients ([C1, C2, ..., C20]).

line_den_coeff

Line / row denominator polynomial coefficients ([C1, C2, ..., C20]).

samp_num_coeff

Sample / column numerator polynomial coefficients ([C1, C2, ..., C20]).

samp_den_coeff

Sample / column denominator polynomial coefficients ([C1, C2, ..., C20]).

An example file with parameters for a single image:

qb2_basic1b.tif:
    im_size: [850, 1450]
    rpc:
        height_off: 703.0
        height_scale: 501.0
        lat_off: -33.6726
        lat_scale: 0.0737
        line_den_coeff: [1.0, -0.001712304, -0.002097415, 0.000339353, 7.299845e-06,
            5.820244e-07, 9.921641e-07, 7.36175e-06, -3.872594e-05, 1.879421e-05,
            8.278992e-08, -1.086149e-07, -8.04155e-06, -6.321182e-08, -3.191499e-08,
            -2.564276e-05, 0.0, 2.19238e-08, 8.902422e-07, 1.212086e-08]
        line_num_coeff: [-0.005096772, -0.03316389, -1.041556, 0.008136379, -0.001495701,
            2.219968e-05, 0.0002853862, 0.0004078997, 0.003128045, -3.121024e-06,
            9.840226e-07, 0.0, 2.233933e-05, -6.402669e-07, -2.263019e-05, -8.066942e-05,
            -1.981754e-05, 7.558916e-08, -9.090734e-07, 1.543458e-07]
        line_off: 399.45
        line_scale: 1210.0
        long_off: 24.4057
        long_scale: 0.0995
        samp_den_coeff: [1.0, -0.001487108, -0.001117242, -0.0005650004, -2.734831e-05,
            3.573053e-06, -1.464e-06, -1.109824e-06, 3.343762e-05, -1.35656e-05, -4.818505e-08,
            3.621381e-08, 2.659397e-07, -5.544073e-08, 5.509497e-07, -6.424512e-07,
            2.825019e-08, -3.761443e-08, -4.643368e-08, 1.469352e-08]
        samp_num_coeff: [0.007721408, 1.01649, 0.001515872, 0.01318289, 0.001093084,
            0.0004559596, -0.0003150691, -0.00626621, -0.0005255268, 8.515037e-06,
            3.483893e-06, 1.580062e-05, -4.605011e-05, -1.336031e-05, 6.30528e-05,
            5.669601e-05, 4.585081e-08, -6.089191e-06, -8.388204e-07, -1.740819e-07]
        samp_off: 637.05
        samp_scale: 1377.6
        err_bias: 12.15
        err_rand: 0.3