Simply find what is hidden in this picture.

The answer is:
ICE CREAM. The reference is "I Scream, You Scream, We All Scream for Ice Cream"
The hidden text is revealed in the bit 0 plane by using the Stegsolve program
I - my first is in ice but not in cream
C - the element Carbon can be hard and precious in a diamond
E - 2.71828 is the number $e$
CREAM - has already been said