Grayscale Image Objects

Hello,

(Posting to the APIs list because this seems to be API specific)

I am using GM 1.2.6 on Windows through the Magic++ API.  In several 
instances I have to construct an Image object from my own internal 
buffers.  I setup the type, colorspace, etc. without issue and populate 
the pixel (and possibly colormap) data.  The problem comes down to the 
internal flags for the image type.  Specifically when I create a grayscale 
 image the "is_grayscale" member never gets set to True which causes 
problems for some of the imaging functions and encoders.  Since 
is_grayscale is not true for instance the JPEG encoder writes out a three 
channel JPEG file instead of a single channel file.  This is much more 
computationally and file size expensive than it should be.

There appears to be a method internally (IsGrayImage) that is called some 
a few functions that sets the is_grayscale member properly however I have 
not found any way to have this function execute via the Magic++ interface. 
 I believe that the is_monochrome member suffers from the same problem.

Is there a way to directly or indirectly get the internal image 
characteristics initialized properly after creating a new image with the 
Magic++ interface?

While I am here I might also ask if there is a recommended combination 
(most efficient) form of grayscale storage for GM?  I ask since they can 
be DirectColor or PseudoColor, and even GrayscaleType and RGBColorspace.


Thanks for your time,

Jon O

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