  We explore the possibility of constraining model parameters of the Epoch of
Reionization (EoR) from 21cm brightness temperature maps, using a combination
of morphological descriptors constructed from the eigenvalues of the Contour
Minkowski Tensor (CMT), Betti numbers (count of connected regions $n_{con}$ and
holes $n_{hole}$) and the area of structures in the excursion set of the field.
We use a three parameter model of EoR simulated using 21\textrm{cmFAST}, namely
the ionizing efficiency of sources $\zeta$, the minimum virial temperature
$T_{vir}$ required for collapse into a halo and the maximum radius for ionizing
radiation described by $R_{mfp}$. We performed a Bayesian analysis to recover
model parameters for a mock 21cm image from SKA phase I at a redshift of
$z=7.4$ corresponding to a mean neutral hydrogen fraction of $\mathrm{\bar
x}_{HI} \simeq 0.5$. We find that in the absence of noise the average size of
structures in the field with $x_{HI} \lesssim 0.5$ is smaller than regions with
$x_{HI} \gtrsim 0.5$ and the structures are equally isotropic when
$\mathrm{\bar x}_{HI}=0.5$ . We also find that in order to recover the input
model to within $1-\sigma$ accuracy for a mock noisy image at a single
frequency channel of $1~\mathrm{MHz}$, for an observation time
$t_{obs}<2000~\mathrm{hrs}$, the noisy $\delta T_b$ map needs to be smoothed at
a scale $R_s>9.5~\mathrm{Mpc}$. Finally we show that the systematic behaviour
of the statistic as ionization progresses, enables us to obtain stringent
constraints on $\mathrm{\bar x}_{HI}$ (with a coefficient of variation $\sim
0.05$ as compared to $\sim 0.1-0.2$ for model parameter constraints), thereby
making these descriptors a promising statistic for constraining EoR model
parameters and the ionization history of the universe.
