Group A Group B Group C
Australia France Serbia
Canada Germany South Sudan
Greece Japan United States
Spain Brazil Latvia
If based on paper,
Group A will have Greece and Canada; Group B, France and Germany, then Group C, USA and Serbia. Let's assume the two best non-group Top 2 will be Spain and Brazil (or Australia)-- the point differential really matters at this point because it's likely going to that tiebreaker with expected same win-loss records for the middle of the pack teams.
From the official Olympics/FIBA page:
The knockout rounds begin with eight teams in the quarterfinals. A random draw will determine the matchups for the quarterfinals, with two important caveats:
The two highest-ranked teams will be placed in the same pot and therefore end up on opposite sides of the bracket.
Teams from the same group can't be drawn against each other in the quarterfinals.
That "random draw" will screw some of the better teams! So say USA has the top spot (win over the other or tiebreak via point differential) and let's give France the other one (Japan and Brazil should give them an easy cushion on padding up that lead)
Potential QF pairings and in consideration those rules of same group can't be drawn vs each other in the semis
QF - Bracket A
USA vs. Greece/Germany/Spain/Canada/Brazil (Can't be drawn vs. Serbia/France)
Greece vs. France/Germany/Brazil/USA/Serbia (Can't be drawn vs Canada/Spain)
QF Bracket B
France vs. Greece/Canada/Serbia/Spain (Can't be drawn vs. Germany, Brazil, USA)
Germany vs. Greece/Canada/USA/Serbia/Spain)(Can't be drawn vs France/Brazil)
Obviously we can go into this QF pairings rabbit hole in details but not much point when "randomness" is involved. Let's just say we get the nicest of pairings this KO round so that we get to see the top/elite teams battle at the top (and just rank them 1-8, per "power rankings")
QF:
USA vs Brazil
Serbia vs Canada
Germany vs Greece
France vs Spain
Then, projected semis; USA vs Serbia and France vs Germany
Again, the random draw will draw a lot of flak when when they get the mighty USA in the QF (and even a bad luck in the same bracket with US in the SF).