简单介绍IOS开发中屏幕亮度和闪光控制
来源：爱站网时间：2021-03-23编辑：网友分享
项目开发中我们发现需要控制屏幕的亮度，而拥有控制亮度的空间要怎么进行区分？文中是爱站技术频道小编带给大家的简单介绍IOS开发中屏幕亮度和闪光控制，需要的朋友们下面来一起看看吧。
项目开发中我们发现需要控制屏幕的亮度，而拥有控制亮度的空间要怎么进行区分？文中是爱站技术频道小编带给大家的简单介绍IOS开发中屏幕亮度和闪光控制，需要的朋友们下面来一起看看吧。
下面来看看详细的介绍：
所用涉及框架：AVFoundation框架和ImageIO
读取屏幕亮度： [UIScreen mainScreen].brightness;
设置屏幕亮度： [[UIScreen mainScreen] setBrightness:0.5];
获取环境亮度主要代码：
- (void)getTorch {
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
AVCaptureDeviceInput *input = [[AVCaptureDeviceInput alloc]initWithDevice:device error:nil];
AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc] init];
[output setSampleBufferDelegate:self queue:dispatch_get_main_queue()];
self.session = [[AVCaptureSession alloc]init];
[self.session setSessionPreset:AVCaptureSessionPresetHigh];
if ([self.session canAddInput:input]) {
[self.session addInput:input];
}
if ([self.session canAddOutput:output]) {
[self.session addOutput:output];
}
[self.session startRunning];
}
- (void)captureOutput:(AVCaptureOutput*)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection*)connection {
CFDictionaryRef metadataDict =CMCopyDictionaryOfAttachments(NULL,sampleBuffer,
kCMAttachmentMode_ShouldPropagate);
NSDictionary *metadata = [[NSMutableDictionary alloc] initWithDictionary:
(__bridgeNSDictionary*)metadataDict];
CFRelease(metadataDict);
NSDictionary *exifMetadata = [[metadata objectForKey:(NSString*)kCGImagePropertyExifDictionary] mutableCopy];
float brightnessValue = [[exifMetadata objectForKey:(NSString*)kCGImagePropertyExifBrightnessValue] floatValue];
NSLog(@"%f",brightnessValue);
// 根据brightnessValue的值来打开和关闭闪光灯
AVCaptureDevice*device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
BOOL result = [device hasTorch];// 判断设备是否有闪光灯
if((brightnessValue 0) && result) {
// 关闭闪光灯
[device lockForConfiguration:nil];
[device setTorchMode:AVCaptureTorchModeOff];//关
[device unlockForConfiguration];
}
}
简单介绍IOS开发中屏幕亮度和闪光控制，大家了解的怎样了呢？其实很多的编程操作大家也都会操作，希望大家能够选择适合自己的操作。
