Original tone mapped image by PTMO {g=2.2, c=1}:

Histogram of the tone mapped image:

Image statistics of the tone-mapped image:

Median percentile of the lightness (CIE L*a*b*): 35.0039
Mean of the chroma value (CIE L*a*b*): 8.2026
Image produced by the generic tone mapping operator:
(evalution of the fit via PSNR: PSNR = 36.4202dB)

Fitted tone curve of the generic tone mapping operator,
compared to the luminance compression done by the tone mapping operator:

Fitted parameters of the generic tmo:

Exposure: 0.57079
Contrast: 1.6947
Low midtone range: 5.2232
High midtone range: 6.3829
Saturation: 0.42896
Frequencies: 0.582, 0.942, 0.986, 0.976, 0.979