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Problem recognizing PDF417 barcode

Hi,

I'm trying to create then read a PDF417 barcode using the Trial SDK.

If i write the barcode into a file then read it : the decode is successfull, but when i print it and scan it : the decoded text is always wrong whatever the dpi or ErrorLevel i use.

If thought it was limitation of the trial SDK so i asqued for a temporary licence, the result is the same.

In the first example, the PDF417 encoded text is "TEST", the ErrorLevel is 2 and i scanned it at 600dpi, the decoded text is "WGTE" (attached file test1.png)

In the second example, the PDF417 encoded text is "This is a test" the ErrorLevel is 2 and i scanned it at 1200dpi, the decoded text is "WGTwghiwgwgs s " (attached file test2.png)

The code i'm using to decode :

BarCodeReader br = new BarCodeReader(new Bitmap(currentScannedImage), BarCodeReadType.Pdf417);
while (br.Read())
{
tbDecode2.Text = br.GetReadType().ToString() + " : " + br.GetCodeText();
}

I'm using Aspose.BarCode and Aspose.BarCodeRecognition v3.0.1

Is there something i'm doing wrong or missing ?

Hi,

Thanks for considering Aspose.

I was able to reproduce the problem and informed the developers about the recognition problem. I have also logged it in our bug tracking system (ID: 11546). We will notify you when there is any progress about the issue or it gets resolved. Sorry for the inconvenience.

any news on this one?

We got the same problem using v 3.0.0.0.
This is quite critical since we are getting bad feedback from our clients...

I finally used an other SDK which works perfectly for my needs.

The issues you have found earlier (filed as 11546) have been fixed in this update.


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I am having what appears to be a similar problem with a scan of a PDF417 barcode. I had been using Aspose BarcodeRecognition 4.6, so I tried using the 5.4 DLL from here: http://www.aspose.com/community/files/51/.net-components/aspose.barcode-for-.net/default.aspx


Under 4.6, it found the scan and returned WGWGWGWGWGWGWG… recurring instead of the 7 digit barcode. Under 5.4, it doesn’t even see a barcode!

Files to be scanned attached.

Please advise.

Code

BarCodeReader reader = new BarCodeReader(“C:\Users\graham\Pictures\scans\scan_POD_Consignment_3587822.jpg”, BarCodeReadType.AllSupportedTypes);
while (reader.Read())
{
isAScan = true;
// get symbology type
Console.WriteLine("Symbology Type: " + reader.GetReadType());
// get code text
Console.WriteLine("CodeText: " + reader.GetCodeText());
}
reader.Close();

Hi Graham,


Thanks for sharing the sample barcode images. I tested your provided samples against the latest build of Aspose.BarCode for .NET 5.4.0. I regretfully inform you that I’m able to replicate the recognition problem. This problem has been logged in our bug tracking system under ticket Id BARCODENET-33463. We will soon investigate the cause of recognition failure. Also, you will be notified once the fix for your problem is available for public use.

Please accept our apologies for your inconvenience.

Hi Graham,

Thanks for your patience. Good news for you is BARCODENET-33463 has now been resolved and its fix will be included in the next version of Aspose.BarCode for.NET (5.6.0). Which is expected after one week. We will inform you via this forum thread as soon as the new release is published.

The issues you have found earlier (filed as BARCODENET-33463) have been fixed in this update.


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Hi Imran,


I can confirm that the current version of barcodereader (5.6) will read the sample 2D barcode I provided in my previous post in this thread - even after I converted it from jpg to png format - but unfortunately, it hasn’t worked with any of the other 3 similar scans I have tried (attached).

Please advise.

Hi Graham,


Thank you for sharing the sample bar code images. I tested your provided samples against the latest build of Aspose.BarCode for .NET 5.6.2. I’m able to replicate the recognition problem. This problem has been logged in our bug tracking system under ticket Id BARCODENET-33619. We will soon investigate the cause of recognition failure. You will also be notified once the fix for your problem is available for public use.

Please accept our apologies for your inconvenience.

Hi Graham,


From the specifics of ticket id BARCODENET-33619, our development team has identified the problem with source images that pdf417 bar code was truncated, and the last stop bar isn’t printed. Whole image’s border acts as a last stop bar. It is the current status of the issue. As soon as we have made some further progress, we would be more than happy to update you as well.

Hi Graham,


We have a good news for you is BARCODENET-33619 has now been resolved and its fix will be included in the next version of Aspose.BarCode for .NET 5.8.0. Which is expected in the middle of October 2013. We will inform you via this forum thread as soon as the new release is published.

The issues you have found earlier (filed as BARCODENET-33619) have been fixed in this update.


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Hi.
We have a problem. We have to read a lot of printed sheets containing PDF417 barcodes that were generated with version 5.4 of Aspose.Barcode and that are giving us reading problems.
We do not have the original data for that information.
The question we want to ask you is if there is any way to read those PDF417s.
I beg you for a quick reply.
Thanks in advance

@RubenL,
You may create a new thread as this is quite old thread and it is better for proper follow up. You may try the scenario with the latest version as we do not test issues with the older versions and as per policy issues are resolved in the latest versions only.

If your issue is not resolved with the latest version, share a runnable console application which is used to create the printed sheet in question, output printed sheets and the code to read these sheets. Also share the details (along with images if any) of the problem which you are facing. We will reproduce the issue here and share our feedback accordingly.

@ahsaniqbalsidiqui,
Thanks for your quick response.
Before opening a new thread, I will tell you what we have tested and tell me if I should open the new thread or nothing can be done for this case.
We generate PDF417 barcodes with version 5.4. We have tried to read them with the latest version of Aspose.Barcode and also with 5.4.
In both cases the reading has failed.
The only option we can think of is a modified version of the barcode reader that, knowing what the problem is, assumes that the last stop bar is missing.
I don’t know if this is possible. If you think you can help us, we open a new thread.
We are a bit desperate. thanks for your help

@RubenL,

If possible (with your current license), you can try Aspose.BarCode for .NET v5.8.0 if it fixes your issue. Please note, in Aspose.BarCode for .NET v5.8.0 we included fixes for recognizing PDF417 codes for scanned images (as the issues are discussed in this thread).

If your issue is not resolved with the suggested older version, as requested earlier, please share the image barcodes, sample code (that you are using with latest version (Aspose.BarCode for .NET 20.10) to retrieve the barcodes). We will log appropriate tickets to evaluate your issue in details and try to figure it out (if possible) soon.

I first it would be better if you start new topic with the question.

I tested pdf417 generation and recognition with 5.4 version (downloaded here) and pdf417. Everything works well.

Test54.zip (602.0 KB)

Miss-recognition could be with low image quality. In new version the recognition quality is greatly increased but it still could have problems with recognition if image has extremely low quality. You could provide us document where you have problems and we will investigate issue (and please create new topic for this).

Hi.
Perfect. I’m going to open a new thread with this problem.
I will give you an example of an image that reads perfectly (generated with version 2.5) and another that gives an error (generated with 5.4).
If you agree, I will accompany you with the code used for reading. In reality, we read these documents with physical barcode readers but they give the same problem.
Regarding the quality of the image, the origin of the images that I am going to send you is a PDF that has one of its pages with those barcodes. I have used a conversion to jpg image from that page.
Thank you so much for everything. I will put in this thread the number assigned to the new topic.