This is the 745th most frequent Finnish word.
kuvan
"Of the picture" or "of the image" (possessive form of "kuva").
In this case, 'kuvan' is in the singular genitive form of 'kuva', and it shows possession, referring to 'the picture's edges'.
Valokuvassa näkyy kuvan reunat.
In the photograph, the edges of the picture are visible.
Here, the word 'kuva' appears in nominative form as part of the expression 'selkeä kuva', meaning 'clear picture'. It represents an abstract concept in the sentence.
Minulla on mielessä selkeä kuva toimenpiteistä.
I have a clear picture of the procedures in my mind.
In this sentence, 'kuvan' is the partitive singular form of 'kuva' (picture), used because it refers to an object being acted upon.