Check out CoreImage ColorControls filter, which has a Saturation parameter:
https://developer.apple.com/library/content/documentation/GraphicsImaging/Reference/CoreImageFilterReference/#//apple_ref/doc/filter/ci/CIColorControls <https://developer.apple.com/library/content/documentation/GraphicsImaging/Reference/CoreImageFilterReference/#//apple_ref/doc/filter/ci/CIColorControls> "To calculate saturation, this filter linearly interpolates between a grayscale image (saturation = 0.0) and the original image (saturation = 1.0).” Doug Hill > On Aug 15, 2017, at 9:23 AM, Sean McBride <s...@rogue-research.com> wrote: > > I get some JPEG data from the network. I want to efficiently decompress this > data into a specific format (8 bit greyscale) and have an NSData of the raw > pixels. What's the best way to do this? > > I'm currently using NSBitmapImageRep initWithData:, then testing if the > result is greyscale or RGB. If the latter, I write my own loop to convert to > greyscale. > > But I'm hoping there is some lower level API available that I can tell > explicitly that I want greyscale... _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
