objective c - iPhone iOS how to instantiate a black and white CGColorSpaceRef? -


i'm working excellent example of converting image grayscale: convert image b&w problem cgcontext - iphone dev

however, purposes, have only pure black , pure white left in image.

it appears so, need pass black , white color space recolor method using call:

cgcolorspaceref colorspace = cgcolorspacecreatewithname(/*black , white name*/);

however, unable find proper ios color space names. found mac, , "color space names" referenced ios docs not point anywhere.

how can create black , white cgcolorspaceref?

thank you!

i not familiar black , white color space can calculate total average rgb value pixels (lets call totalavg) , use threshold. meaning each pixel if rgb average greater calculated totalavg set pure white, otherwise set pure black.

i agree bit of more work thats whay can think of unless find colorspace looking for.


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