A man wearing a white shirt and a hat, riding his bike, makes an obscene gesture to the photographer
The bike rider and the photographer greeted each other warmly.
The bike rider cannot simultaneously make an obscene gesture and have greeted someone warmly
If the bike rider and the photographer are making obscene gestures then they cannot be greeting each other warmly.
It doesn't make sense to make an obscene gesture to a person and then greet them warmly.