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*): 31.6126
Mean of the chroma value (CIE L*a*b*): 9.249
Image produced by the generic tone mapping operator:
(evalution of the fit via PSNR: PSNR = 35.7245dB)

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: 0.70416
Contrast: 1.7172
Low midtone range: 4.2906
High midtone range: 14.014
Saturation: 0.44054
Frequencies: 0.717, 0.951, 0.995, 1.001, 0.996