How does Moto G do HDR?

[REALOldNick]

I know how HDR usually works as I work with DSLRs and do both manual and camera-controlled HDR multiple shots. But some things puzzle me:

- the moto G takes the HDR very quickly and produces a finished result very quickly. I do not reckon that a phone could process multiple HDR shots, of the pixel size that the camera takes, that fast.

- if I pan the camera as I take an HDR shot, there is no blurring of the image, as there would be with my DSLRs. This assumes good light and a fast shutter speed. I _suppose_ the camera could be shooting so fast there is no blur....?

So does anyone know what is happening here? I know a guy was developing a way to actually sample areas of the screen and alter pixels in the sensor to respond, but surely the phones haven't beaten the "real" cameras!

Any help appreciated

Nick

 

[bfldworker]

Ok, here is how it works. And Google/Motorola was damned smart about it. When you take a photo with your phone it doesn't require the full processing power of all for CPU's. What happens is this, being HDR is process intensive it dedicates 3 of the 4 cores to rendering it. The Adreno 305, while it is a single core GPU also lends a hand. That is why it is so much faster on a Moto G when compared to other phones with less then 4 cores.

 

[REALOldNick]

Thanks for the reply. What you say does not quite cover my puzzlement . Firstly, I have done HDR on a full desktop PC and processing a 3-shot, for instance, takes time even on that machine. Secondly, why do I not get blurring/ghosting if I pan the camera while shooting HDR, if it is multi-shot based HDR.

Nick

 

[bfldworker]

Thanks for the reply. What you say does not quite cover my puzzlement . Firstly, I have done HDR on a full desktop PC and processing a 3-shot, for instance, takes time even on that machine. Secondly, why do I not get blurring/ghosting if I pan the camera while shooting HDR, if it is multi-shot based HDR.

Nick

First there are vast differences between the CPU your desktop uses and the SoC the Moto G uses. The SoC the Moto G uses has a integrated GPU and has a shorter pipeline then your desktop CPU. The GPU on the SoC in the G will jump in to take care of complex calculations, which, which is exactly what it does best.

To answer the lack of blurriness, the software has the ability to match shapes, colors, angles and lines it up. It takes all the unless data and discards it.