Q: "A child doing a handstand on the beach." Does this mean that "A child is showing off his athletic abilities."?
A: yes

Q: "A black boy on a mountainside in a foreign country pointing at something." Does this mean that "The boy pointed at something."?
A: yes

Q: "Brown dog chews on bone while laying on the rug." Does this mean that "A brown dog is barking at a cat."?
A: no

Q: "In a crowded concert a man in white is approaching the main singer who is wearing a yellow shirt." Does this mean that "A man is greeting his brother."?
A:
it is not possible to tell