Shown here are two brothers, depicted as the larger ochre U shapes at the top of the painting. They are coming out of law, or initiation time. 

During this time they went into caves, shown here in black, called Paratoon, to undergo their ceremonies. 

The scene depicted here is the Coming Out Ceremony, when men and women - the rows of U shapes - 'sing' as the two brothers, Tjampitjin and Tjapanagrti emerge.