本文主要介绍的是关于iOS屏幕亮度与闪光灯控制的相关内容，分享出来供大家参考学习，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：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
- (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) { // 打开闪光灯 [device lockForConfiguration:nil]; [device setTorchMode:AVCaptureTorchModeOn];//开 [device unlockForConfiguration]; }else if((brightnessValue >0) && result) { // 关闭闪光灯 [device lockForConfiguration:nil]; [device setTorchMode:AVCaptureTorchModeOff];//关 [device unlockForConfiguration]; }} |
总结
以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，谢谢大家对服务器之家的支持。
原文链接：http://www.jianshu.com/p/6a134ecc306a
