What is PSVR's breakout box really about?

[Shifty Geezer]

From here

The power hungry chip in the processor box is a generic Marvel Armada SoC.
http://www.marvell.com/multimedia-s...-ARMADA-1500-Pro4K-Product-Brief-20160727.pdf

There's quite a large heatsink inside too.
...tech specs pasted below for clarity...
This thing is too powerful and versatile for it to be doing just video distortion + pass-through + binaural audio downmix.

The datasheet says up to 12 000 DMIPS on a quad Cortex A9.
According to wikipedia's info (which probably came from ARM's old webpage), each Cortex A9 does 2.5 DMIPS/MHz, so 12 000 / (2.5*4) = 1.2GHz.

It's a full SoC:
- Quad Cortex A9 at 1.2 GHz
- 8*vec4 + 32*vec1 Vivante GPU that is rated at 1GHz (64 GFLOPs) and has full OpenCL 1.2 compliance
- Audio DSP - I wonder if the whole downmix to stereo isn't done through this.
- H264 + HEVC codec, capable of 4K60 (not HDR though, which explains why it's missing in the pass-through)

Put together with 1GB DDR3 1600MHz at 64bit, so 12.8GB/s bandwidth and 4GB of eMMC.

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We were right about the power given active cooling, but what the heck is Sony's thinking here? Is this a PlayStation Streaming box in the making?

 

[Deleted member 13524]

I think this is too powerful even for a streaming box. The Steam Link has full autonomy with a simple OS using a 2D/3D GUI with some apps, and its SoC is a single-core 1GHz ARM v7 core with 512MB RAM.

This is a SmartTV SoC with a moderately powerful CPU for web browsing and javascript apps, and a GPU for some 3D effects in the GUI. There's also a dedicated 2D GPU in there.
The CPU is arguably more powerful than the Wii U's, and the GPU is definitely more powerful than the Vita.

Maybe Sony made it powerful enough so that it can drive its own stuff in the social screen for party games, even with some 3D elements. There's a 4GB "ROM" in there, so Sony may have other plans for it in the long run.
I still wonder if the reprojection really isn't done in the box, as it's closer to the headset's MEMS sensors and it doesn't need anything other than those sensor's info plus the previous 2D frame for each eye.

 

[bgroovy]

It obviously at least renders the cinematic mode since it works when you plug other sources into the HDMI input.

 

[Shifty Geezer]

That's just a simple 3D transform, right? There's loads of room for more functionality. As ToTTenTranz points out, it's a Smart TV box, like various TV dongles. We discussed simulated Virtual Theatre environments, and I think some dark scenes may be possible on this little box. But there must be a plan here, yet Sony haven't talked about it.

 

[Deleted member 11852]

In their own FAQ Sony state:

Q: What is the Processor Unit (PU) and what does it do?
The Processor Unit is a small box that comes with your PS VR, and connects your PS VR to your PS4 and TV and provides HDMI cable management, enabling Social Screen TV output, 3D audio processing and Cinematic Mode.

Q: Does the Processor Unit provide extra processing power to PS4?
No. The PU only assists the PS4 with 3D audio processing, HDMI cable management, Cinematic Mode and the Social Screen TV output.​

Sony's 120Hz reprojection solution is sublime, maybe it just needs that much power to make it happen. Everything has to happen RIGHT NOW, i.e. in under 8ms.

 

[milk]

Well you do need 3D graphics to do warping-unwatping of a frame buffer - well technically you don't need it, but its certainly the most straight foward/efficient way.
How much grunt do you need to do it at 120fps 4k (for the social screen of pro) at as low a latency as possible?

 

[Deleted member 13524]

The Pro does a 4K social screen? I thought there was a hard limit of 720p for that.

 

[Shifty Geezer]

Yep. First I've heard of a higher quality PSVR social screen on Pro.

 

[milk]

oh, I was just assuming it jad to do pass through for pro as well, so It'd have to be able to output a 4k signal, but I have no idea what I'm talking about. Sorry.

 

[Arwin]

Social screen is done in two different ways: when the social screen displays something different from the VR headset, it's done by routing a game dvr stream to the brake out box, and I think actually over USB because for some tvs HDMI is already at its limits with 1080p@60?

For regular output, the warped input for the left eye is stretched into a regular full HD output. And that one will be 980x1080 unwarped and stretched on both PS4 and Pro as far as I know.