objective c - NSBitmapImageRep -initWithFocusedViewRect is doubling size of image -

i have following objective-c function meant resize nsbitmapimagerep designated size.

currently, when working image of size 2048x1536 , trying resize 300x225, function keeps returning nsbitmapimagerep of size 600x450.

- (nsbitmapimagerep*) resizeimagerep: (nsbitmapimagerep*) anoriginalimagerep totargetsize: (nssize) atargetsize {     nsimage* thetempimagerep = [[[nsimage alloc] initwithsize: atargetsize ] autorelease];     [ thetempimagerep lockfocus ];     [nsgraphicscontext currentcontext].imageinterpolation = nsimageinterpolationhigh;     nsrect thetargetrect = nsmakerect(0.0, 0.0, atargetsize.width, atargetsize.height);     [ anoriginalimagerep drawinrect: thetargetrect];     nsbitmapimagerep* theresizedimagerep = [[[nsbitmapimagerep alloc] initwithfocusedviewrect: thetargetrect ] autorelease];     [ thetempimagerep unlockfocus];      return theresizedimagerep; } 

debugging it, i'm finding thetargetrect of proper size, call initwithfocusedrec returns bitmap of 600x450 pixels (high x wide)

i'm @ complete loss why may happening. have insight?

your technique won't produce resized image. 1 thing, method initwithfocusedviewrect:reads bitmap data focused window , used create screen grabs.

you should create new graphics context new nsbitmapimagerep or nsimage of desired size draw image context.

something this.

nsgraphicscontext* context = [nsgraphicscontext graphicscontextwithbitmapimagerep:thetempimagerep];  if (context) {     [nsgraphicscontext savegraphicsstate];     [nsgraphicscontext setcurrentcontext:context];      [anoriginalimagerep drawatpoint:nszeropoint];     [anoriginalimagerep drawinrect:thetargetrect];      [nsgraphicscontext restoregraphicsstate]; } // temp image rep should have resized original.