Question

这个问题似乎有点抽象，但通常我需要开发一个能够同时检测多个条形码（最多3个）的条形码扫描应用程序。任何人都知道这个任务有什么好的api吗？（Swift或Objective C可以）。任何帮助都非常感谢！谢谢。我已经有一个使用Zxing api的应用程序，但似乎没有检测多个条形码的选项。

Answer 1

您需要AVFoundation！ AVFoundation可以扫描条形码。

对此功能的主要兴趣：

#pragma mark - AVCaptureMetadataOutputObjectsDelegate methods
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputMetadataObjects:(NSArray *)metadataObjects fromConnection:(AVCaptureConnection *)connection {
//THIS YOU CAN USE ARRAY OF AVMetadataObjectType
    NSString *supportedBarcodeType = AVMetadataObjectTypeCode128Code;

    for (AVMetadataObject *barcodeMetadata in metadataObjects) {
        if ([barcodeMetadata.type isEqualToString:supportedBarcodeType]) {
            AVMetadataMachineReadableCodeObject *barcodeObject = (AVMetadataMachineReadableCodeObject *)[self.captureLayer transformedMetadataObjectForMetadataObject:barcodeMetadata];
        //barcode is FIND!
            NSString *capturedBarcode = [barcodeObject stringValue];

            return;
        }
    }
}

配置方法：

static char * const metadataOutputQueue = "metadataOutputQueue";

- (void)configureSessionWithError:(NSError **)error {    

    self.captureSession = [[AVCaptureSession alloc] init];

    NSError *inputError = nil;
    AVCaptureDevice *captureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice error:&inputError];

    if ( nil != inputError || nil == input) {
        *error = inputError;
        return;
    }

    [self.captureSession addInput:input];

    AVCaptureMetadataOutput *captureMetadataOutput = [[AVCaptureMetadataOutput alloc] init];
    [self.captureSession addOutput:captureMetadataOutput];

    dispatch_queue_t dispatchQueue = dispatch_queue_create(metadataOutputQueue, NULL);
    [captureMetadataOutput setMetadataObjectsDelegate:self queue:dispatchQueue];
//THIS YOU CAN ADD ARRAY OF AVMetadataObjectType FOR DETECTING BARCODES
    [captureMetadataOutput setMetadataObjectTypes:@[AVMetadataObjectTypeCode128Code]];

    self.captureLayer = [AVCaptureVideoPreviewLayer layerWithSession:self.captureSession];
    [self.captureLayer setVideoGravity:AVLayerVideoGravityResizeAspectFill];
    [self.captureLayer setFrame:self.cameraPreviewView.layer.bounds];

    [self.cameraPreviewView.layer addSublayer:self.captureLayer];

    self.sessionConfigured = YES;
}

技术说明this！您可以在this site

上找到该教程

IOS条码扫描api能够同时读取3个条形码

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