While tinkering with the code in the Falling Matrix question, I was hoping to improve the rendering speed by making the rasterizations of the text grayscale. I changed the base color of the text to white and left the background black. However, this did not yield a grayscale raster. The problem seems to be that Mathematica tries to help with the readability of text by using special antialiasing schemes.
Consider the following test:
GraphicsRow[
Rasterize[#, Background -> Black, RasterSize -> 15,
ImageSize -> 150] & /@ {Style["\[FilledCircle]", White],
Graphics[{White, Disk[]}]}]
Interesting and (I think) undocumented, but the relevant question for me is: How can I control or eliminate this behavior? Adding a ColorConvert[#,"Grayscale"]
or just taking the Norm
s of the ImageData
gives an acceptable result but is pretty slow.