Ios 城市温度、色调和城市曲线不起作用

我的iOS设备不会对Citemperature、Tint和CIToneCurve进行任何处理

但是，万一发生这种情况，皮亚通的做法是正确的

outputImage = [CIFilter filterWithName:@"CIToneCurve" keysAndValues:@"inputImage", image, @"inputPoint0", [CIVector vectorWithX:0 Y:0], @"inputPoint1", [CIVector vectorWithX:0.25 Y:0.25], @"inputPoint2", [CIVector vectorWithX:0.5 Y:0.5], @"inputPoint3", [CIVector vectorWithX:0.75 Y:0.75], @"inputPoint4", [CIVector vectorWithX:1 Y:1], nil].outputImage;

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这有什么问题吗？？？

看起来正确。您是否尝试过先使用setDefaults进行初始化？

使用此代码：它可以工作

- (UIImage*)applyToneCurve:(NSArray*)pointArray {

    if ([pointArray count] < 2) {
        return self;
    }

    CGPoint first = [[pointArray objectAtIndex:0] CGPointValue];

    first.x /= 255.0;
    first.y /= 255.0;

    CGPoint firstPoint = first;

    CGPoint last = [[pointArray lastObject] CGPointValue];

    last.x /= 255.0;
    last.y /= 255.0;

    CGPoint fifthPoint = last;

    CGPoint secondPoint = CGPointMake(0.25, 0.25);
    CGPoint thirdPoint  = CGPointMake(0.50, 0.50);
    CGPoint fourthPoint = CGPointMake(0.75, 0.75);

    for (int i = 1; i < [pointArray count] - 1; i++) {

        CGPoint point = [[pointArray objectAtIndex:i] CGPointValue];

        point.x /= 255.0;
        point.y /= 255.0;

        if (i == 1) {   
            secondPoint = point;
        }
        else if (i == 2) {
            thirdPoint = point;
        }
        else if (i == 3)
            fourthPoint = point;

    }

    CIImage *inputImage = [CIImage imageWithCGImage:self.CGImage];

    CIFilter *toneCurveFilter = [CIFilter filterWithName:@"CIToneCurve"];
    [toneCurveFilter setDefaults];
    [toneCurveFilter setValue:inputImage forKey:kCIInputImageKey];

    [toneCurveFilter setValue:[CIVector vectorWithX:firstPoint.x  Y:firstPoint.y] forKey:@"inputPoint0"];

    [toneCurveFilter setValue:[CIVector vectorWithX:secondPoint.x  Y:secondPoint.y] forKey:@"inputPoint1"];

    [toneCurveFilter setValue:[CIVector vectorWithX:thirdPoint.x Y:thirdPoint.y] forKey:@"inputPoint2"]; 

    [toneCurveFilter setValue:[CIVector vectorWithX:fourthPoint.x Y:fourthPoint.y] forKey:@"inputPoint3"]; 

    [toneCurveFilter setValue:[CIVector vectorWithX:fifthPoint.x Y:fifthPoint.y] forKey:@"inputPoint4"];

    CIImage *outputImage = [toneCurveFilter outputImage];

    CGImageRef ref = [[CIContext contextWithOptions:nil] createCGImage:outputImage fromRect:outputImage.extent];

    UIImage *result = [UIImage imageWithCGImage:ref];

    if (ref) {

        CGImageRelease(ref);
    }

    return result;    
}

-（UIImage*）applyToneCurve:（NSArray*）点数组{
如果（[pointArray计数]<2）{
回归自我；
}
CGPoint first=[[pointArray objectAtIndex:0]CGPointValue]；
第一.x/=255.0；
第一，y/=255.0；
CGPoint firstPoint=第一；
CGPoint last=[[pointArray lastObject]CGPointValue]；
last.x/=255.0；
last.y/=255.0；
CGPoint fifthPoint=最后一个；
CGPoint secondPoint=CGPointMake（0.25,0.25）；
CGPoint thirdPoint=CGPointMake（0.50,0.50）；
CGPoint-fourthPoint=CGPointMake（0.75,0.75）；
对于（int i=1；i<[点阵列计数]-1；i++）{
CGPoint point=[[pointArray objectAtIndex:i]CGPointValue]；
点x/=255.0；
点y/=255.0；
如果（i==1）{
第二点=点；
}
else如果（i==2）{
第三点=点；
}
else如果（i==3）
第四点=点；
}
CIImage*inputImage=[CIImage-imageWithCGImage:self.CGImage]；
CIFilter*toneCurveFilter=[CIFilter过滤器名称：@“CIToneCurve”]；
[toneCurveFilter设置默认值]；
[toneCurveFilter设置值：InputImageForkey:KCIIInputImageKey]；
[toneCurveFilter设置值：[CIVector vectorWithX:firstPoint.XY:firstPoint.Y]forKey:@“inputPoint0”]；
[toneCurveFilter设置值：[CIVector vectorWithX:secondPoint.XY:secondPoint.Y]分叉：@“inputPoint1”]；
[toneCurveFilter设置值：[x:thirdPoint.XY:thirdPoint.Y]forKey:@“inputPoint2”]；
[toneCurveFilter设置值：[x:fourthPoint.XY:fourthPoint.Y]forKey:@“inputPoint3”]；
[toneCurveFilter设置值：[x:fifthPoint.XY:fifthPoint.Y]forKey:@“inputPoint4”]；
CIImage*outputImage=[toneCurveFilter outputImage]；
CGImageRef ref=[[CIContext contextWithOptions:nil]创建CGImage:outputImage fromRect:outputImage.extent]；
UIImage*结果=[UIImage imageWithCGImage:ref]；
如果（参考）{
CGImageRelease（ref）；
}
返回结果；
}

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PointArray从开始到结束包含5个NSValue曲线点。

正常音调曲线是从（0,0）到（1,1）的直线，这是您输入值所形成的直线，是由“设置默认值”设置的直线

正常音调曲线：

如果您更改“inputPoints”以生成不同的曲线，您将看到应用的过滤器。对于负面曝光，请尝试：

inputPoint0 = (0,1)
inputPoint1 = (0.25,0.75)
inputPoint2 = (0.5,0.5)
inputPoint3 = (0.75,0.25)
inputPoint4 = (1,0)

或对于非典型线：