Question

Explain why images cannot be reconstructed from histograms.

Answer 1

ANSWER:

A histogram is a graph that shows the number of pixels for each intensity level in an image.
A histogram does not show us where each intensity pixel is located it just shows us the count of pixels in each intensity level.
Therefore it is ovious that for one histogram there can be can be multiple images but for one image there can only be one histogram.

Therefore an image cannot be reconstructed from histograms.

I would like to explain this by giving you a simple real life example:
Suppose we the count of the number of boys, girls, men and women living in a city. But with this information we cannot reach to any person in the city. But if we know the address of all the people in the city we can easily find the count.
Here we can relate the count as the histogram and the address as the image.