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Workflow@REDCINE


Emanuel A Guedes

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What's REDCINE?

 

«So to answer a question and clear up a misconception - REDCINE is an application that runs on a workstation (for example an Intel Mac) and emulates what we do in real time in camera hardware when we tell it to record an HD format such as 1080p / 24. That is it converts Bayer pattern data to RGB, applies a gamma, color space and white balance correction to the data, scales it to 2K, crops it to 1080p, converts it to 4:2:2 and encodes it.

 

Think of these as complimentary paths. If you know you want 720p or 1080p output you can go direcly there by doing all the processing in camera and recording a compressed 1080p image using REDCODE 4:2:2. Or you could shoot 4K RAW using REDCODE RAW and bring that data set through REDCINE. Yes its a bit slower in post to do that, but the advantge is your initial recording is in 4K, not 1080p, which gives you more options for your footage - for example a 4K DCI, a super quality 35mm film out plus your 1080p HDTV deliverable, as well as a 4K RAW source footage archive.

 

The intent is to provide two easy to use on-board recording workflows, one emulating an existing compressed HD worflow, the other emulating a digital film negative / DI workflow.»

 

Stuart English in dvxuser.com

http://www.dvxuser.com/V6/showpost.php?p=6...mp;postcount=20

Edited by Mr. Emanuel A. Guedes
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Hi,

 

Grr.

 

- New codecs. Unnecessary. Several good ones exist. Format proliferation is a certifiably Bad Thing.

 

- They're doing a good-quality Bayer interpolation and de-artifacting, plus at least one 2D LUT, on a 4K image in realtime? Er, no, not on any currently existing "intel based Mac". Baselight struggles (and succeeds, some of the time) to do one 2D LUT in realtime on dual 3.06Ghz Xeons, let alone anything else.

 

Basic colorimitery operations should happen in one of two places - in the camera, which is probably a bad idea here given the attractiveness of recording raw bayer data, or in post as part of a codec implementation. Not on some potentially unreliable RTOS-based piece of desktop hardware.

 

Phil

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- New codecs. Unnecessary. Several good ones exist. Format proliferation is a certifiably Bad Thing.

 

Phil

 

Reconstruction code for Bayer RAW are generally very camera specific as they have to take into account

camera/sensor specific qualities. There is no DNG equivalent in the motion world where you

can embed the general sensor characteristics for a generic raw codec. In the long run it would

certainly be very nice to have a standardized raw format (possibly put it into dpx v3). The downside is that

there are certain camera/sensor characterisitcs that are not easily generalized that can improve

the quality of the reconstruction.

 

They're doing a good-quality Bayer interpolation and de-artifacting, plus at least one 2D LUT, on a 4K image in realtime?

 

From our experience, doing realtime final quality 4k reconstruction not really necessary. For editing

purposes, you can cut with a proxy quality reconstruction and only generate

the final quality 4k in non realtime once you have your final edit.

 

However, that's not to say that a good quality reconstruction cannot be done in realtime

(with some tradeoffs in algorithm complexity). A prototype version I'm working

on is currently doing the upload/reconstruction/lut/matrix on the gpu in 15 or so ms per frame.

 

Deanan

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Hi,

 

These concerns are valid, but are equally valid when shooting raw images on DSLRs which are then demosaiced by the image loader in the software. They seem to have solved the problem, perhaps by processing the data to an established norm in camera.

 

In this case "codec" is a misnomer in any case. You're not going to play back a 4K AVI or Quicktime movie using some clever codec if you have to demosaic in realtime.

 

Phil

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