Thanks for that pointer Ken - that works very nicely. Regards
Gideon On 17/12/2010, at 2:09 PM, Ken Ferry wrote: > > On Thu, Dec 16, 2010 at 7:48 PM, Gideon King <[email protected]> wrote: > Hi, I have an arbitrary (user supplied) image, and I want to get the RGBA > values of each pixel of the image. I'm thinking that I should create it as an > NSImage and then use the TIFFRepresentation to get it into an > NSBitmapImageRep object, and then walk through and pick up the colors, but it > appears that the NSBitmapImageRep could be in a wide variety of internal > formats. > > Is there either some generic way of finding the RGBA values, or ensuring that > the NSBitmapImageRep is created in a fixed color space that I can code for? > ...or some other way of solving this problem? > > Yes. Create an NSBitmapImageRep in a fixed pixel format and draw the NSImage > in it. Now you have bits in a canonical pixel format. > > The TIFFRepresentation thing is a not very good hack that unfortunately seems > to have critical mass in the community - that code just won't die. > TIFFRepresentation is good method to call if you're sending data outside of > your process, say to the pasteboard or to disk. It's pretty much always > wrong if the data isn't going to leave your address space. > > See the section "NSBitmapImageRep: CoreGraphics impedance matching and > performance notes" in the AppKit release notes for more detail. > _______________________________________________ Cocoa-dev mailing list ([email protected]) 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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [email protected]
