a barcode creation lib for golang

Thank you for replying... but which one is correct?

I am new to programming in Go... and could use a little help with this.... (thanks !)

		bytes := []byte("hello world")
		azCode, _ := aztec.Encode(bytes, aztec.DEFAULT_EC_PERCENT, aztec.DEFAULT_LAYERS)
		azCode, _ = barcode.Scale(azCode, 40, 100)

		retval := A or B 

              return retval

So how do I convert the barcode to a byte array?

( I don't need it in a PNG or other image type... I just need a byte string )

A

retval := []byte(azCode.Content())  // is this right????

or

B

retval := []byte(azCode)

// actually go has a problem with this:
// cannot convert azCode (variable of type barcode.Barcode) to []bytecompilerInvalidConversion

Originally posted by @MichaelLiss in https://github.com/boombuler/barcode/issues/66#issuecomment-871646780

I need to encode the string FNC3+"$P\rI", but encoding \r (carriage return) requires code 128A. Further investigation reveals this library only supports 128B and 128C. Any chance you could add 128A as well?

(FNC3+"$P\rI" is a special code to begin/end programming Datalogic-brand barcode scanners)

Hi, I am trying to use uuid for barcode but every online validator shows resulting image as invalid. This generator produces valid uuid barcode according to this validator.

From what I've gathered it has most likely something to do with the FNC1 character but I have no idea what. I tried to prefix the uuid with it but no success.

I use this code to generate image

code, err := code128.EncodeWithoutChecksum("1234567890")
...
code, err = barcode.Scale(code, 180, 90)
...
err = png.Encode(w, code)

(some lines are skipped) this is what I got in browser and the lower image was generated with web online generator. As you can see there is difference starting from line 19, which makes my barcode incorrect. I tried two different mobile scanners, both of them easily scan lower image but cannot recognize upper one.

Do you have the same barcode for 1234567890?

This library looks just like what I need.

I am planning to integrate it with a USB based bar code reader. Has anyone tried this yet ?

Also reading via the camera on a phone. I can give it a go and submit a sample but wanted to check first it will be accepted ?

Hi!

We're using you library to generate barcodes and so far it been working geat.

However we've hit a road bump in generating a GS1-128 barcode (most likely we've missunderstood how the library works) when it comes to the hidden FNC1 character. Looking though the source it looks like you support this but it's a bit unclear to us how should generate this type of label.

Are we supposed to send in the FNC1 character manually?

Hi, I've catched encoding bug with QR encoded with L error correction level. Data read by scanner has one byte different from original. Data is in base64, and code.Content() returns correct value, so error must be somewhere in rendering.

I don't know QR algorithm internals well, and it could be possible that I simply have to increase error correction level, but I doubt it.

Here is an example code with real value from production: http://play.golang.org/p/IWmXxzQzT3 (it will not work in playground, must be run locally)

qrCode, _ := qr.Encode('http://www.aa.com?a=123', qr.M, qr.Auto)

Scan the QR code and open it with a browser. The request address becomes https://www.aa.com/?a=123

When trying to create a datamatrix from a long text which would result in a 144x144 grid, the code crashes with an index out of range runtime error in /barcode_master/src/github.com/boombuler/barcode/datamatrix/errorcorrection.go:69

As far as I can tell from the datamatrix specs, this type of grid has alternating block size and CWs.

I'm writing an application which generates barcodes for logistics labels and one of the requirements is that the checksum from code 128 subset C barcode is printed on the label. Is there any easy way to access that value using this library?

Hi I got an error when resize barcode which is can not scale barcode to an image smaller than 244x1,I paste the code as blow ` content:="hello code128"

barcodePic, err := code128.Encode(content)

if err != nil {

	return  err

}

codePic, err := barcode.Scale(barcodePic, 200, 30)

if err != nil {

	return  err

}

file, err := os.Create("sample.png")

if err != nil {

	return err

}

defer file.Close()

err = png.Encode(file, codePic)

if err != nil {

	return  err

}

` Pls help to check it Thanks a lot

We have been using https://linux.die.net/man/1/dmtxwrite for a while but I'd like to use more this library.

I'm reading the code and fiddling around to implement a 16x48 datamatrix with a module size of 5 pixels but I have some questions related to a low knowledge of the datamatrix spec and I hoped to receive some feedback.

• What is the ECC Count? https://github.com/boombuler/barcode/blob/master/datamatrix/codesize.go#L8
• Does the encodeText() needs to be changed or is the encoding the same also for rectangular datamatrix?

I'd like to keep this ticket open for future questions and feedbacks as I learn the library and try to implement my changes, hopefully for a successful PR in the future.

The following errors are happening with Go 1.15 on Fedora Rawhide:

github.com/boombuler/barcode/utils
# github.com/boombuler/barcode/utils
./runeint_test.go:7:3: Errorf format %d has arg string(IntToRune(0)) of wrong type string
./runeint_test.go:16:3: Error call has possible formatting directive %d
./runeint_test.go:19:3: Error call has possible formatting directive %d
./runeint_test.go:22:3: Error call has possible formatting directive %d
FAIL	github.com/boombuler/barcode/utils [build failed]

This library is only capable of encoding UTF-8 strings. Many external systems that read barcodes require specific encoding such as ISO-8859-1 or Shift_JIS. This is especially true of legacy hardware.

The ability to specify the encoding of the string would make this library much more useful.

All methods take a string as an input. While raw data could. be base64 encoded. There are applications where barcodes contain a byte array. To the extent that the barcode protocol permits it, it should be possible to have a method that takes a byte array as an input and encodes raw binary data.

Hi, I think i found a strange limitation in the AZTEC barcode. When there is more than 472 chars in the barcode, it is not readable in 33% error code mode :

... cab2d := "lsdkfmlkfmlkmkmezlkfmlzkfkezfezmfkkljkljkljflmfkelmfklmfezlfkezlmfkzlmefkelfkezlmfezmlflemkflmfklzfelzkflmfkezlmfkezmlfkzefkemzlfkmlezkfmzelfkezmkfelzmfkelzmfkzelmfkezmlfkezlmkflemzfklmezfkelzmfkezmlkfezlfkelmzfkezlmfkezmfkezlmkflmezkfezlmfkezmlfkezmlfklmezkflemzfkzemlkflzmekflzemfkezlmkfezmlfkezlmfkezmlfkezflmkezmlfelmzkfelmzfkzekflemzfklmezfkflmezklmfkezlmfkezlmfkezlfkelzmfkelzmfkezmlfkezlmfkezlmfklzmefkmezlfklmezkflemzkfmlezkfmlezkfezflkzemflkzemlfkzelmfkmelzfkmlz"

keyAztec := barcode.RegisterAztec(pdf, cab2d, 33, 0) barcode.Barcode(pdf, keyAztec, posX + 87.1, posY + 66.6, 28, 28, false) ...

=> the generated barcode is not readable. => if you delete one character and generate it again, it works again.

Please tell me if i made a mistake.

Thank you very much, excuse my poor english :).