[Image-SIG] Converting from 24-bit RGB to Black&White

[Fredrik Lundh]

Alexander Belchenko wrote:

> PIL-Handbook.pdf (for version PIL 1.1.3) description of method
> "im.convert(mode) => image" claims:
>
> "When translating a greyscale image into a bilevel image (mode "1"), all
> non-zero values are set to 255 (white). To use other thresholds, use the
> point method."

the 1.1.3 handbook is incorrect.  here's the corresponding text from the
draft docs:

    "When converting to a bilevel image (mode "1"), the source image is
    first converted to black and white. Resulting values larger than 127
    are then set to white, and the image is dithered. To use other
    thresholds, use the point method."

    (from http://www.effbot.org/imagingbook/image.htm )

</F>