Virtual Reality with smartphone: what you need to know

 I'm sure every 3D stereo fan found out about the new Ocullus Rift preorder release and I also know there are few which can afford to throw lots of cash into a "new tech" like Ocullus Rift gear. I will generally talk about VR gaming, since other VR facilities like Cardboard apps and YouTube in VR already exist.

 Most of you 3D fans might already know what to do in order to obtain this kind of VR. Still, this thread will look like a "Smartphone VR for dummies" tutorial

 Smartphone VR is here for a while, it's not nearly the same quality as the incoming advertised VR gears, but it's affordable and not very complicated to attain. The idea is to stream a 3D side-by-side image, with correct aspect ratio to the phone

Long story short, VR on smartphone requirements:

1. A smartphone, obviously, with the following preferences:

• the bigger, the better
• screen resolution - the higher, the better
• processing power - the higher,the better
• orientation system - subject to long stories; the more precise, the better. The phone sensors will hopefully offer the head-tracking data

2. A PC: the more powerful, the better. 

 A good CPU goes long way on reducing latency, since we're talking about streaming. The computer must encode in real-time a video and stream it over network or USB to the smartphone device.

 A good GPU will be capable to make use of the already-existing 3D stereoscopic rendering possibilities in games and other 3D applications.

3. Head gear:

There are lots of them, lots of shapes, lots of different lens quality. I won't specifically recommend any of them. The best solution would be to go to the shelves and test it yourself with your own smartphone. The existent head gears generally look like this:

Practically it's a box of plastic with (more-or-less) the right lenses inside, with ergonomic (again, more-or-less) design and a place for the "VR screen"

 This second picture shows the place where the phone is seated. You can observe the separation wall in the middle. This means the phone should show 2 image instances, one for each eye, regardless if the image is 3D or not.

 The head gears' prices vary but they are known to cost between 15 and 50 EUR/USD. As I said, the best is to test it yourself with an YouTube VR video before buying it.

 Google Cardboard™ can also be used, but generally in gaming, people need hands, so a hands-free device is recommended.

4. Wireless router - While it's an optional requirement (USB Tethering works as well), it's wireless after all. You wouldn't want any wires around when you play a horror game sequence in VR, this I tell you. It's preferable and safer to be completely wireless while having any VR gear

5. Software:

• VR Streaming software: My recommendation would be Trinus VR . This sweet piece of software is developed by a single dedicated guy. The full version price is more than affordable and it is currently available for PC-Android combination. You will need the app installed on your android phone and the server app installed on your PC. You can find details about how to get it working on Trinus VR website. Getting the video stream working is a straight-forward job, finely described while installing the applications on your devices. Trinus VR is not a requirement; you can use any streaming software, although Trinus VR is dedicated to VR by having lots of tuners regarding the video quality versus latency, lens correction and it might be the only app set using the phone sensors for head-tracking, also with all the necessary settings.
• 3D stereoscopic injector: As Trinus VR site itself recommends, there are 2 viable possibilities right now: Tridef  3D and Vireio Perception. Tridef 3D is not free, it costs ~40EUR, sometimes is bundled with 3D displays. Vireio is free, just a bit more complicated to use and not so flexible, at least for me. The injector idea is to take the 3D information from DirectX applications and translate it into 3D image format. In VR case the 3D image format would be a (slightly altered) SBS format.
• The knowledge I posted a while ago. I am talking about obtaining the 8:9 aspect ratio in games. The knowledge was presented for a slightly different scope, but it happened to match the need in VR gaming. I knew at that time (2012) about the VR use, but the VR wasn't so accessible and "mainstream" as today.

Here are some pics from my previous posts, this time in parallel 3D format. You can simply copy them on your smartphone and start a slideshow, no need of any software except the image viewing one. Enjoy the slideshow with your head gear. Careful, the 3D separation is pretty high and some pictures might be "too 3D".

So, as a recap:

In order to "VR" cheaper than with Ocullus, one needs a PC, a decent Android smartphone, streaming software (Trinus VR) and 3D stereo injector for PC gaming with VR (like Tridef). Patience and understanding is an advantage. Reading all the advice you find in Trinus VR help and suggestions is a great way of understanding what you are dealing with.

One shouldn't expect wonders in terms of quality and latency, the VR experience is nowhere near the real VR headsets, but it surely gives you the idea of what VR tech is capable of because this time VR will have a future for sure, since now we have the necessary processing performance for VR to matter.

If you need any particular explanation, feel free to lay a comment.

Cheers