Just started with Tensorflow and Python. Have a question, anybody willing to help?

So I read an image and I have it in a tensor. I have the RGB values in the tensor. Is there a way to manipulate these values using a loop or using functions? I am trying to modify pixel values to, say for example, make the image grayscale, or modify colors.
I can increase /decrease the values using tf.add and tf.sub but don't know how to adjust individual values.

stackoverflow

@samarthagarwal you can do it with opencv. Idk if you can in tf tho..