  We calculate transverse momentum distribution of direct photons from various
sources by taking into account the initial state momentum anisotropy of quark
gluon plasma (QGP). The total photon yield is then compared with the recent
measurement of photon transverse momentum distribution by the PHENIX
collaboration. It is also demonstrated that the presence of such an anisotropy
can describe the PHENIX photon data better than the isotropic case in the
present model. We show that the isotropization time thus extracted lies within
the range $1.5 \geq\tau_{\rm iso} \geq 0.5$ fm/c for the initial condition used
here.
