AUGMENTED REALITY SDKs: WHAT TO CHOOSE?
In this article we will review the main SDKs to develop Augmented Reality applications in Unity. We will focus in the different pros and cons of each one of them.
Vuforia focuses its tracking methods in images and patterns. This can sound limited but this SDK has a variety of target types, so it can emulate 3D tracking methods by using images as cubes, cuboids or cylinders (figure 1 and figure 2). Another good point in Vuforia SDK is the use of virtual buttons. They allow us to create touchable zones in our tracking image and emulate buttons in the real world rather than in the device (figure 3).
Vuforia SDK is totally free, the only cost being for the cloud service, this is huge boost for indie studios or people who want to start with Augmented Reality. There is also a huge community behind it, so the user can take advantage of that when they needs to ask something: answers and solutions are handy, thanks to their forum. On the other hand, with more tracking methods Vuforia could probably be more competitive.
Metaio undoubtedly offers the most complete tracking methods (tracking for 2-D images, 3-D objects and environments, SLAM instant tracking, barcodes, QR-codes, location-based tracking and Continuous Visual Search). In earlier versions there was a lack of tutorials and that created a steep learning curve, but the increasing availability of tutorials and an active forum have lowered the barrier to entry (figure 4 and 5). One of the new features of Metaio (still in beta) is the face tracking method (figure 6). Metaio offers a free trial for the SDK with watermarks, but the price of the pro version ($3500 – $5500) is high compared to other solutions.
Total immersion, previously known as D’Fusion, is the best option for body and face tracking. As of writing this article however, they have now left the mobile world and
are only offering their SDK for On-stage Events, Interactive Kiosks (in-store and outdoor), and Giant Screens. In most cases, the application requires specific features like HD video, multiple cameras, Infra-Red cameras, or specific sensors (figure 7).
Arpa SDK is relatively new and they have yet to make improvements. Their GPS tracking method is a good pro, but their Unity plugins show three different versions: Android,
iOS and Windows. Productivity would increase if a single plugin grouped all platforms. Communication with the sales department and the access to their SDK are not very clear, these are factors that need to be improved. Anyway it is good to see a new enterprise in the AR sector.
To get ARToolkit you need to sign a monthly subscription (from €1000/month to €3500/year) which has a higher price when compared to other SDKs. Indeed, there are other ones offering expensive licenses, but these are one-time purchases only.
There is not a lot of documentation and the community doesn’t seem very active, but they do answer all questions very quickly. One interesting point for ARToolkit is the possibility of using 3D objects as trackers by using their own tracking creation tool (figure 8). However the use of the Unity plugin is tedious, there is not enough documentation and it is hard to run even their own examples (figure 9).
13th Lab, with their PointCloud SDK, developed the first iOS app that employed SLAM technology. One of their main disadvantages is that, nowadays, the app only works with iOS. PointCloud is one of the few of its kind that offers SLAM tracking (figure 10). Actually, the 13th Lab team has been acquired by Facebook to join their Oculus team. They have just announced that there will be no new updates for Unity 5, so maybe the project is discontinued.
Orbotix offers the most limited SDK in this overall review. It is oriented only to their Sphero device. However, that is exactly what makes it special. They’re adding a new and funny way to make Augmented Reality, and the SDK uses a remotely controlled device as tracker. The SDK detects the ball or roller, overlays the AR content and makes both interact (figure 11).
PROS & CONS
▪ Vuforia: Qualcomm’s vuforia has a lot of pros, it’s totally free and provides great documentation with great community supporting the SDK. Also have a lot of features making it a great option. For me one of the best.
▪ Metaio: The price of the SDK is high but not the highest in the market, it’s principal pro is the huge number of features that Metaio implements. If you can dream it, is possible that Metaio can do it. The other best Augmented Reality SDK for Unity.
▪ Total Immersion: The main pro for D’fusion Total Immersion is the body and face tracking, but it has also two big cons: the price and it is no longer available for mobile platforms.
▪ Arpa Solutions: Arpa is the newest and his main con is the poor info and documentation about it.
▪ 13th Lab: PointCloud is one of the few SDK offering SLAM targeting but it has great cons. The project will be discontinued soon and it only supports iOS platform.
▪ ARToolkit: Offers 3D tracking as Metaio does, but the price difference between the SDKs makes ARToolkit losing battle.
▪ Orbotix: The best thing about Orbotix is its originality but this is also it’s main con because it is a limited one.