I was afraid of that… The only thing I found that gave me a clue on how to do that specifically, did a hard freeze on the phone when I attempted to implement it.
On Jul 11, 2011, at 5:30 PM, Steve Christensen wrote: > The first thing I notice is that none of the CGContext* calls after > UIGraphicsBeginImageContext is referring to that image context so they are > having no effect on it. You should move the UIGraphicsGetCurrentContext down > after the [drawImage...] call. > > If you are still not able to get the desired result with any of the Quartz > blend modes, you'll need to create a bitmap context and tweak the pixels in > the pixel buffer directly. > > > On Jul 11, 2011, at 8:48 AM, Development wrote: > >> Sorry I figured since it was only a sudo change anyway it wouldn't matter. >> >> UIImage * drawImage = rotatingView.image; >> CGContextRef context = UIGraphicsGetCurrentContext(); >> CGRect newRect = CGRectMake(0.0, 0.0, rotatingView.frame.size.width, >> rotatingView.frame.size.height); >> >> UIGraphicsBeginImageContext(newRect.size); >> [drawImage drawInRect:newRect]; >> CGContextTranslateCTM(context, 0.0, rotatingView.frame.size.height); >> CGContextScaleCTM(context, 1.0, -1.0); >> CGContextClipToMask(context, newRect, drawImage.CGImage); >> CGContextSetBlendMode(context, kCGBlendModeHue); >> CGContextSetRGBFillColor(context, self.color.r ,self.color.g , >> self.color.b, 1.0); >> CGContextFillRect(context, newRect); >> UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext(); >> UIGraphicsEndImageContext(); >> >> This applies a colored rectangle applied over the image and clipped to >> it as a mask. Which is not what I want. But even it if was the problem is >> that when I get the png rep so I can save it with transparency to the >> document, the applied color is lost. An easy way around this is to sable the >> color values and reapply because when the document is "flattened" and save >> as a png the color appears correctly. >> But again that's effort in the wrong direction anyway. >> A side note the alpha is 1.0 right now, but in the finished product I >> thought I'd use a slider to adjust that as intensity or something. Anyway it >> doesn't matter it's just a colored rectangle over top of the image. >> >> >> On Jul 11, 2011, at 5:16 AM, Mike Abdullah wrote: >> >>> Giving us a link to the example code would be a big help in understanding >>> what you're trying. >>> >>> On 11 Jul 2011, at 02:06, Development wrote: >>> >>>> Im having a problem with adjusting the color values of a UIImage. >>>> >>>> How does one adjust levels and color values of a UIImage. >>>> The example code I found only overlays a rectangle clipped to an image >>>> mask. It looks like color value adjustment until you realize 2 things. >>>> a) I absolutely cannot render the image view with the color adjustment >>>> into a graphic context with the adjustment in tact, because what I always >>>> get back is the original, unadjusted image. >>>> a b) it's not really adjusting the levels. And since it isn't it also >>>> means I cannot actually adjust the brightness, contrast or anything else >>>> either. >>>> >>>> >>>> Is adjusting UIImage color levels even possible? > _______________________________________________ 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: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
