Thank you for your inquiry and sharing sample.
We have investigated the issue. It was found that the sample image shared by you contains the supplement barcode but it is blurred and some lines are merged. Due to this reason, Aspose.BarCode is unable to extract the supplement barcode. The issue has been logged into our system with ID BARCODENET-36557. Our product team will further look into it and provide feedback. We will update you with the feedback in this thread once available.
Regarding your previous issue, following code snippet recognizes the barcode and supplement barcode from sample image (PB_2016_06.jpg) successfully.
Aspose.BarCode.BarCodeRecognition.BarCodeReader reader =
reader.RecognitionMode = Aspose.BarCode.BarCodeRecognition.RecognitionMode.MaxBarCodes;
reader.ChecksumValidation = Aspose.BarCode.BarCodeRecognition.ChecksumValidation.Default;
string codeText = reader.GetCodeText();
string codeType = reader.GetCodeType().ToString();
string codeChecksum = reader.GetCheckSum();
Console.WriteLine(codeType + ":" + codeText + "," + codeChecksum);