iphone - CIFilter 集成仅适用于 CISepiaTone

Question

以下代码为图像添加了漂亮的棕褐色效果，但是当我选择另一个过滤器时，例如:CIBloom 我根本看不到任何图像。你能帮忙吗？

- (void)drawRect:(CGRect)rect
{
    UIImage *megan = [UIImage imageNamed:@"megan.png"];

    CIImage *cimage = [[CIImage alloc] initWithImage:megan];

    CIFilter *myFilter = [CIFilter filterWithName:@"CISepiaTone"];

    [myFilter setDefaults];
    [myFilter setValue:cimage forKey:@"inputImage"];
    [myFilter setValue:[NSNumber numberWithFloat:0.8f] forKey:@"inputIntensity"];

    CIImage *image = [myFilter outputImage];
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef cgImage = [context createCGImage:image fromRect:image.extent];
    UIImage *resultUIImage = [UIImage imageWithCGImage:cgImage];
    CGImageRelease(cgImage);

    CGRect imageRecht = [[UIScreen mainScreen] bounds];
    [resultUIImage drawInRect:imageRecht];
}

根据我的理解，我应该能够只编辑以下行来更改过滤器:

CIFilter *myFilter = [CIFilter filterWithName:@"CIBloom"];
[myFilter setValue:[NSNumber numberWithFloat:10.0f] forKey:@"inputIntensity"];

但是当我这样做时，我在启动应用程序时根本看不到任何图像。

Answer 1

CISepiaTone 适用于 Mac OS X v10.4 及更高版本以及 iOS 5.0 及更高版本，而 CIBloom仅适用于 Mac OS X v10.4 及更高版本。

https://developer.apple.com/library/mac/#documentation/graphicsimaging/reference/CoreImageFilterReference/Reference/reference.html