Question

Is CIColorPosterize available in iOS ? I am using following code for core image filter but the filter value is always 0. Filter for sepia is working fine . I just wanted to know that if CIColorPosterize is available in iOS and if yes what is the problem in my code.An help is appreciated.

-(void)imageDraw{

UIImage *image = [UIImage imageNamed:@"cat2.jpg"];

CIImage *beginImage = [CIImage imageWithCGImage:[image CGImage]];
CIContext *context = [CIContext contextWithOptions:nil];
 CIFilter* posterize = [CIFilter filterWithName:@"CIColorPosterize"];
[posterize setDefaults];
[posterize setValue:[NSNumber numberWithDouble:8.0] forKey:@"inputLevels"];
[posterize setValue:beginImage forKey:@"inputImage"];


CIImage *outputImage = [posterize outputImage];

CGImageRef cgimg = [context createCGImage:outputImage fromRect:[outputImage extent]];
UIImage *newImg = [UIImage imageWithCGImage:cgimg];


imgVIew.image = newImg;
 ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];  

[library writeImageToSavedPhotosAlbum:[newImg CGImage] orientation:(ALAssetOrientation)           [newImg imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){  
    if (error) {  
        NSLog(@"error");  
    } else {  
        NSLog(@"url %@", assetURL);  
    }  
}];  

CGImageRelease(cgimg);
}

Answer 1

Update

CIColorPosterize is now available for iOS 6

-(void)logAllFilters {
    NSArray *properties = [CIFilter filterNamesInCategory:
      kCICategoryBuiltIn];
    NSLog(@"%@", properties);
    for (NSString *filterName in properties) {
        CIFilter *fltr = [CIFilter filterWithName:filterName];
        NSLog(@"%@", [fltr attributes]);
    }
}