ios - 如何在自定义相机上使用 UISlider 调整亮度？

Question

iOS 8 Camara 具有在点击相机时调节亮度的功能。

我也尝试过这段代码，但不起作用。

  AVCaptureDevice *device =[AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

  AVCaptureWhiteBalanceGains deviceWhiteBalance;// = [device deviceWhiteBalanceGains];

 AVCaptureWhiteBalanceTemperatureAndTintValues tempAndTint = [device temperatureAndTintValuesForDeviceWhiteBalanceGains:[device deviceWhiteBalanceGains]];

tempAndTint.temperature = (slider.value*100)*10000/100;
if (slider.value < 0.50) {
    tempAndTint.tint = -(slider.value*100)*150/100;
}
else{
    tempAndTint.tint = (slider.value*100)*150/100;
}


deviceWhiteBalance = [device deviceWhiteBalanceGainsForTemperatureAndTintValues:tempAndTint];
[device chromaticityValuesForDeviceWhiteBalanceGains:deviceWhiteBalance];


dispatch_async(dispatch_get_main_queue(), ^{

    AVCaptureDevice *device =[AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if (device) {
        [device setWhiteBalanceModeLockedWithDeviceWhiteBalanceGains:deviceWhiteBalance completionHandler:^(CMTime syncTime) {

        }];
    }
});

Answer 1

我找到了解决方案。并获取ios 8.0以下版本支持的每一个新变化

AVCamMenual - ios 8 Camera features