Algorithm 1: Description of the dark current calibration of the LJ1-01 nighttime sensor

Input:$D{N}_{i,j}{}^{org}$ from dark current calibration data includes the low- and high-gain images, i = 1, 2, 3, … N, j = 1, 2, 3, … M

Output: the dark current calibration results $C_i$ and $\overline{C}$

for each j = 1 to M do

Compute the average value of each frame of data:

$Mea{n}_j={\displaystyle \sum _i^N}D{N}_{i,j}{}^{org}$

end for

Eliminate the gross error and compute the valid $D{N}_{i,j}$:

$D{N}_{i,j}=D{N}_{i,j}{}^{org},\left|D{N}_{i,j}{}^{org}-Mea{n}_j<5\right|$

for each i = 1 to N do

Compute the dark current value of each detector:

$C_i=\frac{1}{M}{\displaystyle \sum _j^M}D{N}_{i,j}$

end for

Compute the dark current correction reference:

$\overline{C}={\displaystyle \sum _i^N}{C}_i$

Use the calibration results $C_i$ and $\overline{C}$ to correct the $D{N}_i$ of each single frame:

$D{N}_{c,i}=D{N}_i-C_i+\overline{C}$

return$C_i$, $\overline{C}$.