tf.image.per_image_standardization
Linearly scales each image in image
to have mean 0 and variance 1.
tf.image.per_image_standardization(
image
)
For each 3D image x
in image
, computes (x  mean) / adjusted_stddev
, where

mean
is the average of all values in x

adjusted_stddev = max(stddev, 1.0/sqrt(N))
is capped away from 0 to protect against division by 0 when handling uniform images 
N
is the number of elements in x

stddev
is the standard deviation of all values in x
Args 
image  An nD Tensor with at least 3 dimensions, the last 3 of which are the dimensions of each image. 
Returns 
A Tensor with the same shape and dtype as image . 
Raises 
ValueError  if the shape of 'image' is incompatible with this function. 