How is this technique implemented?
I noticed that they(like Bartender) don't directly concatenate commands like ZPL (etc.).
And also they don't use bitmap(GDI,GDI+ images) transfer to printer-driver.
Printer-based Serialization In print jobs that include serial numbers, many printers can accept a starting value and the incremental
step size. When you use this printer-based serialization, you can
print a large number of serialized items without having to send any
data after the first label.
Printer-based Barcodes Printers that have built-in barcode functionality make it possible for software programs to request
complex barcodes by using simple text strings (such as “1234”). This
process is much faster than sending bitmap images (or pictures) of
barcodes that consume hundreds or thousands of extra bytes per printed
item. (When you use software other than BarTender, our driver fonts
give you some limited functionality.)
Printer-based barcodes are, as you mention, barcodes that have the symbology / definition stored in the printer firmware. Much like a DLL that you give "12345" and as a result gets a bitmap, an SVG file etc etc.
Many modern label printers know a bunch of common symbologies such as EAN, DM, QR, UPC and similar.
The benefit is obviously that it makes transfer of data much more efficient. Instead of sending a (large) image for every print, the software just sends initial definition (layout, symbology choice and options, ..) + the value needed. Taken to the next level, the printer could receive metadata such as "take this layout, make 500 labels, and in the barcode start at 1, increase 1 every label".
Some disadvantages are
is that the appearance is left to the firmware designer of the printer firmware
There may be less coordination between what's being designed and what's being printed, although typically the driver for the printer should adress this.
The printer firmware may not be updated if the barcode symbology specifications has been updated
The printer firmware may contain only a subset of the barcode definition
In short, simplificy vs freedom of parameters and appearance.
How it is technically implemented (at printer end, from receiving the number to drawing the actual barcode) is probably out of scope for this forum.
Example specification (in newer printer model)
Looking at a random Zebra Printer (ZT600) the built-in barcodes covers nearly every use:
1D symbologies
Code11, Code39, Code93, Code128 (all subsets),
UCC, ISBT, UPC, EAN 8 / 13, UPC/EAN extensions,
Plessey, Postnet, 2of5, Logmars, MSI, Codabar and Planet Code
2D symbologies
codablock, PDF417, Code49, Datamatrix,
QR, TLC39, MicroPDF, RSS14 +composite and Aztec.
When you print an element on a label (barcode or text) you can do that by sending a graphic field or by instructing the printer to pick up the element internally and build the element with the configuration you need.
For example, in case you want to print a text, the ZPL command will include the font you want to use, vertical and horizontal size, position of the text and so on.
In the case of a barcode, the barcode selector contained in the ZPL command, will automatically recall the .BAR file stored in the Z memory, which contains the instructions for the printer to build the barcode, then, in the same command and likewise for the text, you have also provide the size of the barcode (usually it's a ratio between the narrow and the bold line), the position, the human readable line and so on.
The graphic method is used for example when a font which is not stored on the printer memory is used: the printer doesn't recognize the font and so it can't build the text, so the print can happen only after a conversion of the text field into a graphic field. This works well with text fields, but the barcodes can have quality issues as, due to how a thermal printers physicall works, the lines of a barcode can be printed like a sort of saw. Moreover you can't see or edit the data since the code is basically unreadable, that's why it's impossible to send serialized data, unless you use a software.
The element printing is not affected by this type of quality issues and allows you to edit the data.
If you want to see the difference, try to use zebradesigner and print to file a label with a barocode. When you select a barcode, you can choose to print it as a graphic or to use the printer element and you'll see that the .prn files will contains different data.
This is what you get using the printer element (128 barcode containing 123456789012)
https://justpaste.it/66gvp
and this is the same barcode printed as graphic field
https://justpaste.it/27abu
I'm trying to create 2D barcode images with iOS and CoreImage using a CIFilter for CIAztecCodeGenerator. Depending on the length of the text and the error correction level settings, CIFilter.outputImage sometimes returns nil.
The following message is printed on the console only:
Unable to create barcode. The message is too large for an Aztec
barcode.
A similar message will be printed when using CIQRCodeGenerator.
Is there a way to catch this kind of error for CIFilter in code or find out in advance if the text will be too long to be processed?
Thank you very much for any suggestions!
The maximum size of the data depends on the correction level and also on the type of message that you want to encode. For example if your text only have numbers then a different encoding is used to put that data in the barcode and more characters will be allowed. You cannot really detect that specific error but you can always just check if the result was nil. If it was nil then probably beacuse message was too long.
According to documentation at https://developer.apple.com/library/archive/documentation/GraphicsImaging/Reference/CoreImageFilterReference/index.html#//apple_ref/doc/filter/ci/CIAztecCodeGenerator :
The full-size format can store up to 1914 bytes of message data
(including correction) in up to 32 layers, producing a barcode image
sized no larger than 151 x 151 pixels.
Also at https://help.accusoft.com/BarcodeXpress/v13.2/BxNodeJs/aztec.html you will find this 1914 bytes value. So probably you could assume that anything that is not larger than 1914 bytes should be successfully encoded by CIAztecCodeGenerator, but encoding anything above that size could fail.
I am using the simple code below and as titled. How can I print simple Code39 or UPC? Even code39 of the same data prints unreadable bars that are different per data but do not scan.
I am using a IDTech Shuttle to swipe card data in my iOS app and I need to send Track1 and Track2 as separate values to my card processor. I have researched getting track1 and track2 data and it looks pretty straight forward except my returned swipe data does not follow the same format as described my all of the posts I have read.
My swipe data looks something like this:
J(LbÐðhQRÍm©½gÝD|}xÆÁ°ø)Cc+%N9;Aq6*ØÉ\ØsÀüÝXþYü;tHÎMHãøÃH¡æ´v¤æe£õ®;PJá#÷{oö zú5OËáÒðìåÍ.;°¿äT125007331bI$A
Æ
How do I parse that into 2 separate tracks? I am assuming there is some sort of format here
IDTECH encrypted devices (ED), Shuttle included, are HEX output and HID. You will need to acquire the SDK for the Shuttle specifically as there are 2 output formats for IDTECH ED's and I think the Shuttle uses the newer of the 2.
You can then build a parser which will count the field lengths, some are are just 2 (I believe the first 6 to 8 are) and some are variable with padding to conform to a fixed length.
I believe you can there are 3 fields, track 1 and 2, track 1 and track 2, you would be interested in.
I'm developing an IOS app that reads Arduino serial output via redpark cable.
In the Arduino side, it uses Serial.println() to send out strings.
The string is in the format of "12.34x334.45x0.34x123x33". Essentially it's a combination of doubles with "x" in between as a special split character.
My initial thought was that in the app side, it would get the Arduino output line by line so I would just use
NSString *testString= #"12.34x334.45x0.34x123x33";
NSArray *array = [testString componentsSeparatedByString:#"x"];
to get a NSArray contains 12.34 334.45 0.34 123 and 33.
Somehow after reading questions and answers posted here, I figured out there is no way for redpark sdk to treat the Arduino output line by line, it's always in a X bytes basis.
In order to parse the Arduino output string correctly, what should i do? Would it be a good idea to add leading and tailing 0 to my double data to make the original string to be sent in a fixed length?
(i.e. "03.45x45.50x02.30" to make it 17 bytes and try to read 17 bytes of data using redpark sdk?)
The Redpark SDK only grabs the incoming serial data stream, but doesn't (despite having a few helper routines) interpret it as packets. You'll need to code that yourself. As suggested by agentatlarge in the comments to your question, read the data into a buffer using readBytesAvailable:numBytes until you get a new line character (ASCII 13), at which point you have your string to parse and can start over.
Alternatively, skip the initial string: read the incoming data until you get an "x" (at which time you add a string to an NSMutableArray) or a new line character (at which point you process the array and start a new one.
Be aware that, using the default settings (configurable in redparkSerial.h) data will be fed to you in chunks limited to 100ms (rxForwardingTimeout) or 16 bytes (rxForwardCount), whichever comes sooner. So your system will need to be able to handle multiple reads until it is certain that it has received all the data in a packet (printed line), evidenced by the arrival of the new line character.