GPUImage – 像素色值亮度平均(漫画效果) GPUImageAverageLuminanceThresholdFilter

/******************************************************************************************/
//@Author:猿说编程
//@Blog(个人博客地址): www.codersrc.com
//@File:GPUImage – 像素色值亮度平均(漫画效果) GPUImageAverageLuminanceThresholdFilter
//@Time:2022/03/28 07:30
//@Motto:不积跬步无以至千里，不积小流无以成江海，程序人生的精彩需要坚持不懈地积累！
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#import "GPUImageAverageLuminanceThresholdFilter.h"
#import "GPUImageLuminosity.h"
#import "GPUImageLuminanceThresholdFilter.h"

@interface GPUImageAverageLuminanceThresholdFilter()
{
    GPUImageLuminosity *luminosityFilter;
    GPUImageLuminanceThresholdFilter *luminanceThresholdFilter;
}
@end

@implementation GPUImageAverageLuminanceThresholdFilter

@synthesize thresholdMultiplier = _thresholdMultiplier;

#pragma mark -
#pragma mark Initialization and teardown

- (id)init;
{
    if (!(self = [super init]))
    {
        return nil;
    }

    self.thresholdMultiplier = 1.0;

    luminosityFilter = [[GPUImageLuminosity alloc] init];
    [self addFilter:luminosityFilter];

    luminanceThresholdFilter = [[GPUImageLuminanceThresholdFilter alloc] init];
    [self addFilter:luminanceThresholdFilter];

    __unsafe_unretained GPUImageAverageLuminanceThresholdFilter *weakSelf = self;
    __unsafe_unretained GPUImageLuminanceThresholdFilter *weakThreshold = luminanceThresholdFilter;

    [luminosityFilter setLuminosityProcessingFinishedBlock:^(CGFloat luminosity, CMTime frameTime) {
        weakThreshold.threshold = luminosity * weakSelf.thresholdMultiplier;
    }];

    self.initialFilters = [NSArray arrayWithObjects:luminosityFilter, luminanceThresholdFilter, nil];
    self.terminalFilter = luminanceThresholdFilter;

    return self;
}

@end