現在、iOS 7 の最新の API を使用してコード 39 バーコードをスキャンしようとしていますが、気が狂いそうです。それを検出するために、電話を特定の方法で10秒ほど静止させる必要があります。Red LaserやZbarなどと比べてみたところ、少しずれても1秒で解析できました。キャプチャ セッションをロードする方法が原因なのか、それとも何なのかはわかりません。助けていただければ幸いです。パフォーマンスを改善する方法について何か提案はありますか?
viewDidLoad メソッドでスキャナーをロードする方法は次のとおりです。
//Initialize Laser View
laserView = [[UIView alloc] init];
laserView.autoresizingMask = UIViewAutoresizingFlexibleTopMargin|UIViewAutoresizingFlexibleLeftMargin|UIViewAutoresizingFlexibleRightMargin|UIViewAutoresizingFlexibleBottomMargin;
laserView.layer.borderColor = [UIColor redColor].CGColor;
laserView.layer.borderWidth = 8;
laserView.layer.cornerRadius = 10;
[self.view addSubview:laserView];
//Start Session
scannerSession = [[AVCaptureSession alloc] init];
scannerDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
//Define Error Messages
NSError *error = nil;
//Define Input
scannerInput = [AVCaptureDeviceInput deviceInputWithDevice:scannerDevice error:&error];
//Check if Device has a Camera
if (scannerInput) {
[scannerSession addInput:scannerInput];
} else {
NSLog(@"Error: %@", error);
}
// Locks the configuration
BOOL success = [scannerDevice lockForConfiguration:nil];
if (success) {
if ([scannerDevice isAutoFocusRangeRestrictionSupported]) {
// Restricts the autofocus to near range (new in iOS 7)
[scannerDevice setAutoFocusRangeRestriction:AVCaptureAutoFocusRangeRestrictionNear];
}
}
// unlocks the configuration
[scannerDevice unlockForConfiguration];
//Define Output & Metadata Object Types
scannerOutput = [[AVCaptureMetadataOutput alloc] init];
[scannerOutput setMetadataObjectsDelegate:self queue:dispatch_get_main_queue()];
[scannerSession addOutput:scannerOutput];
scannerOutput.metadataObjectTypes = [scannerOutput availableMetadataObjectTypes];
//Create Video Preview Layer
scannerPreviewLayer = [AVCaptureVideoPreviewLayer layerWithSession:scannerSession];
scannerPreviewLayer.frame = self.view.bounds;
scannerPreviewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
[self.view.layer addSublayer:scannerPreviewLayer];
//Start Session
[scannerSession startRunning];
[self.view bringSubviewToFront:cancelButton];
[self.view bringSubviewToFront:laserView];
と：
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection {
//Prepare Laser View
CGRect laser = CGRectZero;
//Format Date
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"M/d"];
//Format Time
NSDateFormatter *timeFormatter = [[NSDateFormatter alloc] init];
[timeFormatter setDateFormat:@"h:ma"];
//Define Barcode Types to Recognize
AVMetadataMachineReadableCodeObject *barCodeObject;
NSString *idNumber = nil;
NSArray *barCodeTypes = @[AVMetadataObjectTypeCode39Code];
if ([metadataObjects count] > 1) {
NSLog(@"%lu Barcodes Found.", (unsigned long)[metadataObjects count]);
}
//Get String Value For Every Barcode (That Matches The Type We're Looking For)
for (AVMetadataObject *metadata in metadataObjects) {
for (NSString *type in barCodeTypes) {
//If The Barcode Is The Type We Need Then Get Data
if ([metadata.type isEqualToString:type]) {
barCodeObject = (AVMetadataMachineReadableCodeObject *)[scannerPreviewLayer transformedMetadataObjectForMetadataObject:(AVMetadataMachineReadableCodeObject *)metadata];
laser = barCodeObject.bounds;
idNumber = [(AVMetadataMachineReadableCodeObject *)metadata stringValue];
break;
}
}
// If IDNumber Found
if (idNumber != nil) {
//Stop Session
[scannerSession stopRunning];
[self vibrate];
NSLog(@"ID: %@", idNumber);
break;
}
//If IDNumber Is Not Found
else {
NSLog(@"No ID Found.");
}
}
//Update Laser
laserView.frame = laser;
}