How to Get Barcode Location

Once a barcode is found, you could be inclined to highlight it on the image for a better user experience. In this article, we will explain how to get the coordinates of the barcode so that they can be used to highlight the barcode.

BarcodeResultItem

A barcode result is returned as a BarcodeResultItem which provides a method GetLocation to get the result coordinate points. The result points are listed in clockwise order, starting from the top-left point of the barcode area. The next section will explore the different code snippets for each supported programming language.

Code Snippet

The following code snippet shows how to get the coordinates of the barcode:

• JavaScript
• C++
• Android
• Objective-C
• Swift

const result = await cvRouter.capture(file, "ReadSingleBarcode");
for (let item of result.items) {
  if (item.type === Dynamsoft.Core.EnumCapturedResultItemType.CRIT_BARCODE) {
    console.log("Point 0: " + JSON.stringify(item.location.points[0]));
    console.log("Point 1: " + JSON.stringify(item.location.points[1]));
    console.log("Point 2: " + JSON.stringify(item.location.points[2]));
    console.log("Point 3: " + JSON.stringify(item.location.points[3]));  
  }
}

CCaptureVisionRouter* cvr = new CCaptureVisionRouter;
CCapturedResult* result = cvr->Capture("IMAGE-FILE-PATH", CPresetTemplate::PT_READ_BARCODES);
if (result->GetErrorCode() != 0) {
    cout << "Error: " << result->GetErrorCode() << "," << result->GetErrorString() << endl;
}
CDecodedBarcodesResult* barcodeResult = result->GetDecodedBarcodesResult();
if (barcodeResult != nullptr || barcodeResult->GetItemsCount() != 0)
{
    for (int index = 0; index < barcodeResult->GetItemsCount(); ++index)
    {
        const CBarcodeResultItem* barcode = barcodeResult->GetItem(index);
        CQuadrilateral location = barcode->GetLocation();
        cout << "Result " << index + 1 << endl;
        cout << "Point 0: [ " << location.points[0][0] << ", " << location.points[0][1] << " ]" << endl;
        cout << "Point 1: [ " << location.points[1][0] << ", " << location.points[1][1] << " ]" << endl;
        cout << "Point 2: [ " << location.points[2][0] << ", " << location.points[2][1] << " ]" << endl;
        cout << "Point 3: [ " << location.points[3][0] << ", " << location.points[3][1] << " ]" << endl;
    }
    barcodeResult->Release();
}
result->Release();
// more process here

public void onDecodedBarcodesReceived(DecodedBarcodesResult result) {
    if (result != null){
        BarcodeResultItem[] items = result.getItems();
        for (int i=0; i < items.length; i++){
            BarcodeResultItem item = items[i];
            Quadrilateral barcodeQuadArea = item.getLocation();
            Point topLeftPoint = barcodeQuadArea.points[0];
            Point topRightPoint = barcodeQuadArea.points[1];
            Point bottomRightPoint = barcodeQuadArea.points[2];
            Point bottomLeftPoint = barcodeQuadArea.points[3];
            Log.i("DecodedBarcodes", "onDecodedBarcodesReceived: This is the number "+i+" barcode");
            Log.i("DecodedBarcodes", "The first point is: ("+topLeftPoint.x+", "+topLeftPoint.y+")");
            Log.i("DecodedBarcodes", "The second point is: ("+topRightPoint.x+", "+topRightPoint.y+")");
            Log.i("DecodedBarcodes", "The third point is: ("+bottomRightPoint.x+", "+bottomRightPoint.y+")");
            Log.i("DecodedBarcodes", "The fourth point is: ("+bottomLeftPoint.x+", "+bottomLeftPoint.y+")");
        }
    }
}

- (void)onDecodedBarcodesReceived:(DSDecodedBarcodesResult *)result {
    if (result.items.count > 0) {
        for (DSBarcodeResultItem *item in result.items) {
            DSQuadrilateral *barcodeQuadArea = item.location;
            CGPoint topLeftPoint = [barcodeQuadArea.points[0] CGPointValue];
            CGPoint topRightPoint = [barcodeQuadArea.points[1] CGPointValue];
            CGPoint bottomRightPoint = [barcodeQuadArea.points[2] CGPointValue];
            CGPoint bottomLeftPoint = [barcodeQuadArea.points[3] CGPointValue];
        }
    }
}

func onDecodedBarcodesReceived(_ result: DecodedBarcodesResult) {
    if let items = result.items, items.count > 0 {
        for item in items {
            let barcodeQuadArea = item.location
            let topLeftPoint:CGPoint = barcodeQuadArea.points[0] as! CGPoint
            let topRightPoint:CGPoint = barcodeQuadArea.points[1] as! CGPoint
            let buttomRightPoint:CGPoint = barcodeQuadArea.points[2] as! CGPoint
            let bottomLeftPoint:CGPoint = barcodeQuadArea.points[3] as! CGPoint
        }
    }
}