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Commented Unassigned: Unable to create 8-bit grayscale JPEG-2000 images [1420]

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As I discuss in [this post](https://magick.codeplex.com/discussions/660276) and these ImageMagick forum posts (the ["Users" forum](https://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=31094); as well as the ["Magick.NET" forum](https://www.imagemagick.org/discourse-server/viewtopic.php?f=27&t=31095)), I am unable to successfully create 8-bit grayscale JPEG-2000 images in Magick.NET.

I __am__ able to successfully create 8-bit grayscale images via the command line in ImageMagick, so I believe the problem is not a deeper issue with ImageMagick. Rather, Magick.NET does not respect commands to change the Color.

With certain commands (see my discussion linked above in the Magick.NET forum), the JPEG-2000 metadata changes, but the file size does not change appreciably, suggesting that the actual imagery data being written is not changing. With other commands, neither the metadata nor the file size change.
Comments: As requested [here](https://magick.codeplex.com/discussions/660276), I've uploaded a test 8-bit grayscale bitmap that reproduces the issue. It's not the same file that I've been using, but it still illustrates the discrepancy. [Here is a Google Drive link.](https://drive.google.com/open?id=0B2YsHp3KHrDrbUxCNFJFOVUyU28) When I use Magick.NET (version 7.0.3.500-Q8-x86), without setting to Grayscale, the jp2 file size is 698 KB. When I set m.ColorSpace to ColorSpace.Gray, the jp2 file size actually increases to 702 KB. When I use the ImageMagick command-line "convert" tool on Linux Mint (version 6.7.7-10), without setting to Grayscale, the jp2 file size is 698 KB (the same as from Magick.NET). When I pass the "-colorspace gray" argument, the file size decreases to 665 KB. Not as dramatic of a decrease in file size as I saw with my other file, but it still illustrates a discrepancy in the behavior of the command line vs. Magick.NET. Could it be related to the version numbers of the two libraries? Has anything changed in the JPEG-2000 encoder between ImageMagick 6.7.7-10 and Magick.NET 7.0.3.500?

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