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View Full Version : Debayering: Rocket vs. software



Petri Teittinen
06-04-2010, 01:09 AM
A friend of mine acquired a RRocket and was surprised to see that it produces worse-looking debayering than RC-X without Rocket.

Rocket's output seems somewhat sharper but at the same time coarser and less pleasing to the naked eye. Running a simple gaussian blur at 0.4 takes care of that to some degree, but he was especially worried about the moiré around fine diagonal lines like hair. He sent me a couple of comparison photos but I'd have to verify whether it's OK to post them here first since they are from a recent shoot.

Deanan & co., can RRocket's debayering be improved or is it baked permanently into the silicon?

Deanan
06-04-2010, 01:34 AM
Some people prefer Rocket's debayer (sharper looking) and others prefer the software debayer (smoother).

We are working on a hybrid for both rocket and software that combines the best of both.

Michael Moreno
06-04-2010, 03:20 AM
Thanks Deanan

So me being one that prefers the smoother
is it possible to have rocket work half as fast
and just give me smoother as opposed to sharper
is this what you mean by hybrid

sorry it kinda scares me because I thought rocket just gave same results just at a faster rate. I like Reds organic image, not sharp Hd.

Got my fingers crossed and positive energy flowing ; )

Thanks

Petri Teittinen
06-04-2010, 04:49 AM
Deanan, thank you taking the time to reply.

Steven Caesare
06-04-2010, 06:58 AM
Deanan, can you expand on why this is?

I would have assumed that the same algorithm is being executed in hardware as is contained in the software.

If not, what's the reasoning behind it?

Thanks.

-sc

Jordan Livingston
06-04-2010, 07:51 AM
My 2-Cents: After color grading, compositing, scaling, etc.; it has always benefit me to start with a sharper image as it will inevitably get softer throughout the workflow. Also, as Petri rightly pointed out; artful softening in post is easily achieved whereas post sharpening can be a mixed bag.

- Jordan

Martin Jäger
06-04-2010, 09:31 AM
Thanks Deanan

So me being one that prefers the smoother
is it possible to have rocket work half as fast
and just give me smoother as opposed to sharper
is this what you mean by hybrid

sorry it kinda scares me because I thought rocket just gave same results just at a faster rate. I like Reds organic image, not sharp Hd.

Got my fingers crossed and positive energy flowing ; )

Thanks


... I had exactly the same in mind - i wouldn't mind (coming straight from transcoding hell without ROCKET). But as Petri pointed out I get pleasing results by applying a 0.4 gaussian - I haven't had time to see whether my worries about the moiré are justified - at least with fast moving footage there is nothing to worrie - AND we are speaking about a full 4k image conversion - since most of my products end up at max 2k for the moment,
i might react a bit oversensitive here - I'm just a purist loving the smooth :)

btw:I'm that friend of Petri :)

Stacey Spears
06-04-2010, 10:16 AM
I prefer the sharper look of Rocket myself.