Hi,
I don't understand the meaning of the "aspect_ratio" metadata field in the BRAW API. For example with the given SDK Samples A056_08251956_C074.braw we have :
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A056_08251956_C074.braw
Aspect Ratio : 2.35:1
Image Size (Width x Height): 4608 x 2592
==> Width/Height = 16:9
Stretch Factor = Aspect Ratio / ( Width/Height ) = 1.321875
A056_08251956_C074.braw shown in square pixels looks perfectly fine. So the correct Aspect Ratio should be 16:9. Not sure about the meaning of 2.35, should we stretch horizontally the footage by the computed Stretch Factor ? That wouldn't make sense for this footage because it already looks fine in square pixels.
But then if I have a look at a BMPCC6K sample footage A001_06260425_C006.braw shot in anamorphic :
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A001_06260425_C006.braw
Aspect Ratio : 2.40:1
Image Size (Width x Height): 3728 x 3104
==> Width/Height = 1.201
Stretch Factor = Aspect Ratio / ( Width/Height ) = 1.998
Corrected Stretch Factor = 2.0
So the Stretch factor would be 2.0 (almost, but let's take into account that the Blackmagic camera had to take a resolution multiple of 8) and it would make sense here (i.e. footage doesn't look fine in square pixels, but does look fine after taking into account the Corrected Stretch factor)
What am I missing ? And how does the camera know that the user is shooting anamorphic ?
Thanks!