Hard to really tell from that angle, angle from the front would be good but I think you could stand to tighten your body more and sit further back when you squat down. I could not good a good look at where your knees were going. Looked like you were looking up on the ascent and leaning to far forward, keep your eyes focused on something straight ahead of you and keep your chest up throughout the movement to keep from leaning over too much.
Thats all I really noticed though. Hope that helps.