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I am trying to generate PDF417 barcode images, but I am noticing that the online generators give different results.

For example, entering the same data and using "text" encoding with the same row/column sizes will give two different barcodes with these two online generators.

http://www.racoindustries.com/barcodegenerator/2d/pdf417.aspx

http://generator.onbarcode.com/online-pdf417-barcode-generator.aspx

What is the explanation behind this variation?

Thanks!

QQ_QQ
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1 Answers1

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To encode a PDF417 barcode, the input text (e.g. "text") undergoes a number of operations, converting all the text into numbers, applying algorithms, etc. and out the other end comes rows and rows of blocks. These blocks are stacked on top of each other to create a 2D barcode.

It looks like the OnBarcode generator has the "Number of Rows" setting as defaulted to 30, forcing the barcode to be that number of rows. The extra space is filled with nothingness. The Raco one defaults to Automatic, which doesn't need filling with nothingness.

Set the following settings to be the same on both, and they will both produse the same result:

  • Error Correction
  • Row Count
  • Column Count

Results from both providers when settings are the same

Raco

Raco Version

OnBarcode

OnBarcode version

Michael Rodrigues
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  • Thank you for your reply! But, I have made sure that the row/column settings were the same on both sites, as well as using the same error correction level. But the images are still different. – QQ_QQ Jul 29 '12 at 22:55
  • I have added the output from each provider. As you can see, when the settings are the same, they produce the same output. Raco adds a white border, hence the indenting. The slight stretchedness doesn't make any difference, as long as the block sequences are the same. – Michael Rodrigues Jul 29 '12 at 23:55
  • Very strange.. I have tried: Data = 12345, Rows = 8, Columns = 3, Error level = 2, Data mode = Text And I get different results... – QQ_QQ Jul 30 '12 at 01:12
  • It seems that the Truncate PDF option is the cause of the difference. Don't use this option, it will probably make your barcode unusable. – Michael Rodrigues Jul 30 '12 at 02:02
  • Okay, I have tried this, but it seems to still not work :( The left/right indicators match, which should mean the row/column/etc settings are matching. But the data area isn't matching.. I've tried it with the same "12345" text data as above. Ahhh... so confusing... – QQ_QQ Jul 31 '12 at 05:36
  • I tried it again, and they match. Could you please post another side-by-side picture like you did before, but this time with Truncated = False? – Michael Rodrigues Jul 31 '12 at 22:42
  • Hm, Interesting. Both barcodes are readable, and both contain "12345". There is a slight difference in the encoding. PDF414 barcodes contain a lot more data than just the encoded text. This is used to re-constuct the encoded text in case the barcode was damaged or scanned a bit uncleanly (If you scribble on the barcode, or cut out a chunk, it will still read properly.) It's possible that Raco and OnBarcode encode this extra data a tiny bit differently. – Michael Rodrigues Aug 02 '12 at 01:44
  • Ah.. I see. So both should be valid for usage. Thank you! – QQ_QQ Aug 02 '12 at 12:17