iOS 人臉識別
阿新 • • 發佈：2019-01-07
1.在控制其中新增如下屬性
2.懶載入/** 輸入裝置 */ @property (nonatomic,strong) AVCaptureDevice *device; /** 攝像頭輸入流 */ @property (nonatomic,strong) AVCaptureDeviceInput *deviceInput; /** 攝像頭輸出流 */ @property (nonatomic,strong) AVCaptureVideoDataOutput *videoDataOutput; /** 流 */ @property (nonatomic,strong) AVCaptureSession *session; /** 輸出重新整理執行緒 */ @property (nonatomic,strong) dispatch_queue_t videoDataOutputQueue; /** */ @property (nonatomic,strong) AVCaptureVideoPreviewLayer *previewLayer; /** 人臉識別 */ @property (nonatomic,strong) CIDetector *faceDetector;
- (CIDetector *)faceDetector{ if (_faceDetector == nil) { NSDictionary *faceDetectorOptions = [NSDictionary dictionaryWithObjectsAndKeys:CIDetectorAccuracyLow, CIDetectorAccuracy, nil]; _faceDetector = [CIDetector detectorOfType:CIDetectorTypeFace context:nil options:faceDetectorOptions]; } return _faceDetector; }
3.初始化所有屬性
4.實現代理，檢測人臉/** * 初始化 人臉識別 */ - (void)setupDetector { // 1.裝置方向 self.devicePosition = AVCaptureDevicePositionFront; // 2.獲取設別 for (AVCaptureDevice *device in [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]) { if (device.position == self.devicePosition) { self.device = device; break; } } // 處理設別不存在 if (!self.device) { // 設別不存在 #warning TODO NSLog(@"設別不存在"); } NSError *error = nil; // 3.輸入流 self.deviceInput = [[AVCaptureDeviceInput alloc] initWithDevice:self.device error:&error]; // 處理輸入流異常 if (error) { #warning TODO NSLog(@"輸入流初始化異常"); } // 4.處理輸出流執行緒 #define FYFVideoDataOutputQueue "VideoDataOutputQueue" self.videoDataOutputQueue = dispatch_queue_create(FYFVideoDataOutputQueue, DISPATCH_QUEUE_SERIAL); // 5.輸出流(從指定的視訊中採集資料) self.videoDataOutput = [[AVCaptureVideoDataOutput alloc] init]; // 設定採集相片的畫素格式 NSDictionary *rgbOutputSettings = [NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCMPixelFormat_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey]; [self.videoDataOutput setVideoSettings:rgbOutputSettings]; // 處理輸出執行緒被阻塞時，丟棄掉沒有處理的畫面 [self.videoDataOutput setAlwaysDiscardsLateVideoFrames:YES]; // [self.videoDataOutput setSampleBufferDelegate:self queue:self.videoDataOutputQueue]; // 6.設定 session self.session = [[AVCaptureSession alloc] init]; // 1>設定取樣質量 [self.session setSessionPreset:AVCaptureSessionPresetHigh]; // 2>新增輸入流 if ([self.session canAddInput:self.deviceInput]) { [self.session addInput:self.deviceInput]; } else { // 處理不能新增 input } // 3>新增輸出流 if ([self.session canAddOutput:self.videoDataOutput]) { [self.session addOutput:self.videoDataOutput]; } else { // 處理不能新增 output } // 7.相機層建立 self.previewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:self.session]; self.previewLayer.videoGravity = AVLayerVideoGravityResizeAspect; [self.previewLayer.connection setVideoOrientation:AVCaptureVideoOrientationLandscapeRight]; //self.previewLayer.frame = self.view.bounds; // 8.在 view 中新增 PreviewLayer CALayer *rootLayer = [self.view layer]; [rootLayer setMasksToBounds:YES]; self.previewLayer.frame = rootLayer.bounds; [rootLayer insertSublayer:self.previewLayer atIndex:0]; // 9.開始 [self.session startRunning]; }
#pragma mark - AVCaptureVideoDataOutputSampleBufferDelegate
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection {
// 獲取圖片
// CVPixelBuffer(core video pixel buffer)： 指的是主記憶體中的圖片快取，用來儲存圖片畫素資料。應用程式在產生圖片幀、解壓縮視訊資料或呼叫Core Image的時候可以呼叫此物件
// 實時處理帶監測的圖片
CVPixelBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
// CMAttachmentBearer是一個基於CF的物件，支援鍵/值/模式 附件API。 任何CF物件都可以新增到CMAttachmentBearer物件，來儲存額外資訊
CFDictionaryRef attachments = CMCopyDictionaryOfAttachments(kCFAllocatorDefault, sampleBuffer, kCMAttachmentMode_ShouldPropagate);
CIImage *ciImage = [[CIImage alloc] initWithCVPixelBuffer:pixelBuffer options:(__bridge NSDictionary *)(attachments)];
if (attachments) {
CFRelease(attachments);
}
NSDictionary *imageOptionPortrait = [NSDictionary dictionaryWithObject:[self getImageOrientationByDeviceOrientation:UIDeviceOrientationPortrait] forKey:CIDetectorImageOrientation];
NSDictionary *imageOptionPortraitUpsideDown = [NSDictionary dictionaryWithObject:[self getImageOrientationByDeviceOrientation:UIDeviceOrientationPortraitUpsideDown] forKey:CIDetectorImageOrientation];
NSDictionary *imageOptionLandscapeLeft = [NSDictionary dictionaryWithObject:[self getImageOrientationByDeviceOrientation:UIDeviceOrientationLandscapeLeft] forKey:CIDetectorImageOrientation];
NSDictionary *imageOptionLandscapeRight = [NSDictionary dictionaryWithObject:[self getImageOrientationByDeviceOrientation:UIDeviceOrientationLandscapeRight] forKey:CIDetectorImageOrientation];
NSMutableArray *allFeatures = [NSMutableArray array];
[allFeatures addObjectsFromArray:[self.faceDetector featuresInImage:ciImage options:imageOptionPortrait]];
[allFeatures addObjectsFromArray:[self.faceDetector featuresInImage:ciImage options:imageOptionPortraitUpsideDown]];
[allFeatures addObjectsFromArray:[self.faceDetector featuresInImage:ciImage options:imageOptionLandscapeLeft]];
[allFeatures addObjectsFromArray:[self.faceDetector featuresInImage:ciImage options:imageOptionLandscapeRight]];
if (allFeatures.count) {
// 檢測到人臉
} else {
// 未檢測到人臉
}
}
5.其他方法
/**
* 根據裝置方向獲取圖片的方向
*/
- (NSNumber *)getImageOrientationByDeviceOrientation:(UIDeviceOrientation)deviceOrientation {
int imageOrientation;
enum {
PHOTOS_EXIF_0ROW_TOP_0COL_LEFT = 1, // 1 = 0th row is at the top, and 0th column is on the left (THE DEFAULT).
PHOTOS_EXIF_0ROW_TOP_0COL_RIGHT = 2, // 2 = 0th row is at the top, and 0th column is on the right.
PHOTOS_EXIF_0ROW_BOTTOM_0COL_RIGHT = 3, // 3 = 0th row is at the bottom, and 0th column is on the right.
PHOTOS_EXIF_0ROW_BOTTOM_0COL_LEFT = 4, // 4 = 0th row is at the bottom, and 0th column is on the left.
PHOTOS_EXIF_0ROW_LEFT_0COL_TOP = 5, // 5 = 0th row is on the left, and 0th column is the top.
PHOTOS_EXIF_0ROW_RIGHT_0COL_TOP = 6, // 6 = 0th row is on the right, and 0th column is the top.
PHOTOS_EXIF_0ROW_RIGHT_0COL_BOTTOM = 7, // 7 = 0th row is on the right, and 0th column is the bottom.
PHOTOS_EXIF_0ROW_LEFT_0COL_BOTTOM = 8 // 8 = 0th row is on the left, and 0th column is the bottom.
};
switch (deviceOrientation) {
case UIDeviceOrientationPortraitUpsideDown: // Device oriented vertically, home button on the top
imageOrientation = PHOTOS_EXIF_0ROW_LEFT_0COL_BOTTOM;
break;
case UIDeviceOrientationLandscapeLeft: // Device oriented horizontally, home button on the right
// if (self.isUsingFrontFacingCamera)
imageOrientation = PHOTOS_EXIF_0ROW_BOTTOM_0COL_RIGHT;
// else
// exifOrientation = PHOTOS_EXIF_0ROW_TOP_0COL_LEFT;
break;
case UIDeviceOrientationLandscapeRight: // Device oriented horizontally, home button on the left
// if (self.isUsingFrontFacingCamera)
imageOrientation = PHOTOS_EXIF_0ROW_TOP_0COL_LEFT;
// else
// exifOrientation = PHOTOS_EXIF_0ROW_BOTTOM_0COL_RIGHT;
break;
case UIDeviceOrientationPortrait: // Device oriented vertically, home button on the bottom
default:
imageOrientation = PHOTOS_EXIF_0ROW_RIGHT_0COL_TOP;
break;
}
return [NSNumber numberWithInt:imageOrientation];
}6.重置
// clean up capture setup
- (void)teardownAVCapture {
for(AVCaptureInput *input in self.session.inputs){
[self.session removeInput:input];
}
for(AVCaptureOutput *output in self.session.outputs){
[self.session removeOutput:output];
}
[self.session stopRunning];
self.videoDataOutput = nil;
self.videoDataOutputQueue = nil;
self.device = nil;
[self.previewLayer removeFromSuperlayer];
self.previewLayer = nil;
}