Hyundai surprised a lot of people when it revealed the Veloster in 2011. It has an off shape but is still very original to many even a few years later. However, the design language of the company has moved forwards since it was made and therefore the car needs to be brought forwards as well. This explains why spy photographers have seen a car in testing.
The vehicle has a lot of camouflage though and this means that it is hard to make out exactly what it look like underneath. There are enough clues to confirm that it is a Veloster though, such as the dual exhaust tops in the centre which imply that it is a turbo version and not the naturally aspirated one. It also looks as though there is a bigger grille on this model perhaps like the one on the Genesis as well as new bumpers on both the front and the back of the car. It does look like the right hand side half door will still be there but the wheels look like they will be new. Inside it looks like there might be new additions, perhaps an updated infotainment system.
Mechanical changes are not obvious and nothing has yet been confirmed officially either. However, it does look as though it may not be too long before the new version will be shown and then we will be able to get a really good look at it.