ios 模糊处理

-(UIImageView *)QiuTanTiYuBigImageView{
    if (!_QiuTanTiYuBigImageView) {
        _QiuTanTiYuBigImageView = [[UIImageView alloc]init];
        UIBlurEffect * QiuTanTiYuEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];
        UIVisualEffectView * QiuTanTiYuEffectView = [[UIVisualEffectView alloc]initWithEffect:QiuTanTiYuEffect];
        QiuTanTiYuEffectView.frame = CGRectMake(0, 0, TYZXWIDE, TYZXHEIGHT);
        QiuTanTiYuEffectView.alpha = 0.8;
        [_QiuTanTiYuBigImageView addSubview:QiuTanTiYuEffectView];
    }
    return _QiuTanTiYuBigImageView;
}