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CAM_ACTIVE_AREA for SD4000 (RAW/DNG)

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Offline reyalp

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Re: CAM_ACTIVE_AREA for SD4000 (RAW/DNG)
« Reply #20 on: 06 / March / 2011, 17:40:34 »
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1) DNG format have provision to pinpoint active area
2) The dark frame could be used by other software
3) Writing the raw data is faster when including all the sensor area :)
DNG data should always include the full sensor data. Active area is metadata set in DNG. My feeling is that anything that contains usable image data should be included, and pixels that are completely masked should be excluded. There is a separate setting for the default crop area, which we set to the size of the jpeg (but not exactly the same location!)
Don't forget what the H stands for.

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Offline pixeldoc2000

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Re: CAM_ACTIVE_AREA for SD4000 (RAW/DNG)
« Reply #21 on: 07 / March / 2011, 17:40:36 »
3) Writing the raw data is faster when including all the sensor area
As reyalp already answered, DNG always contain all RAW data. Active Area is only Meta Data in DNG to tell viewer software which area from RAW to show (area of "valid" pixel).

My feeling is that anything that contains usable image data should be included,
You mean include Dark Frame in DNG Active Area.

There is a separate setting for the default crop area, which we set to the size of the jpeg (but not exactly the same location!)
Already noticed it, bit annoying...

I've modified pallete.png with white background to make it easier to see Dark Frame in DNG.
Here is a direct compare between JPG and DNG with Dark Frame on SD4000.
There is a lot of postprocessing for JPG going on...
« Last Edit: 07 / March / 2011, 17:50:00 by pixeldoc2000 »

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Offline reyalp

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Re: CAM_ACTIVE_AREA for SD4000 (RAW/DNG)
« Reply #22 on: 07 / March / 2011, 22:27:41 »
You mean include Dark Frame in DNG Active Area.
If it has recoverable image data. I would expect most DNG users to crop their images anyway, but maybe I'm wrong.
Quote
There is a separate setting for the default crop area, which we set to the size of the jpeg (but not exactly the same location!)
Already noticed it, bit annoying...
It would be good to match the jpeg, but unless you can find the offsets in the firmware, manually finding on every camera would be quite annoying.
Don't forget what the H stands for.

 

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