Wiki Education Foundation-supported course assignment edit

  This article was the subject of a Wiki Education Foundation-supported course assignment, between 6 September 2019 and 12 December 2019. Further details are available on the course page. Student editor(s): Tt1887.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 19:03, 16 January 2022 (UTC)Reply

Old discussion edit

Has anyone else noticed the Datamatrices on USPS mail other than me? On mail mostly from cities, I've seen them to the left of the stamp. Note: none of them had actual stamps, just the postal meter thing or whatever it is so it might just be part of that.

Lee S. Svoboda 01:10, 7 September 2005 (UTC)Reply

Yes. If you use USPS online postage, it prints Datamatrices. ≈ jossi ≈ 02:30, September 7, 2005 (UTC)

Tools, specifications edit

Well, a bit unrelated, but did anyone ever tried to collect

  • free tools (source) to create datamatrices
  • free tools (source) to decode datamatrices (would be nice to have something to decode a clean, computer generated code at least)
  • downloadable [free] specifications?

I have found a free source to generate datamatrix code from text, file or stamp information, but wondering whether there's available a decoder anywhere? --grin 14:51, 8 November 2005 (UTC)Reply

Here are some source codes to create datamatrices: http://www.aaisp.net.uk/aa/free/ --Antifumo 00:30, 6 March 2006 (UTC)Reply

The libdmtx project: "libdmtx is a shared library for Linux that can be used to read (scan & decode) and write (encode & print) 2D Data Matrix barcode symbols. It is released under the LGPL and can be used and distributed freely under these terms.", see http://www.libdmtx.org/

During the period when I worked most heavily with Data Matrix codes, from 1999 to early 2005, I had not heard of any freeware decoders. They may exist, but to my knowledge the few independent programmers who bothered to create decoders (and encoders) were interested in charging for their work. I'd be surprised if anyone would offer as freeware a decoder capable of reading anything more than high contrast codes such as those created by an inkjet or laser printer on paper. If you do find a free decoder, please post about it here. Most likely you'd be interested in a decoder for ECC 200 codes.
"Data Matrix" (two words) is the proper name for the code. I'm not sure how to change the article name, but the single word spelling "Datamatrix" is not the standard.
"Data matrix" is a term in scientific statistical calculations. Dysmorodrepanis 00:53, 29 October 2006 (UTC)Reply
For info on standards, check out http://www.rvsi.net/DM%20Organizations.html
-Rethunk 07:26, 19 December 2005 (UTC)Reply

Notes edit

I'm in a bit of a hurry, otherwise I'd make these changes myself. (A lame excuse, I know, but there it is.)

Symbols have an even number of rows and an even number of columns. This is true for the ECC 200 format, but not of the Data Matrix in general. ECC 140 codes, for instance, have an odd number of rows and columns.

ECC200 is the newest version of Datamatrix and supports advanced encoding error checking and correction algorithms (such as Reed-Solomon) ECC 200 uses Reed-Solomon alone.-Rethunk 07:38, 19 December 2005 (UTC)Reply

This sentence is probably somewhat confusing for readers: Today it is covered by an ISO standard, ISO/IEC16022—International Symbology Specification, Datamatrix, and is in the public domain, which means it can be used free of any licensing or royalties. Correction: Acacia (www.acaciatechnologies.com) owns the patent for many 2D barcodes - including DataMatrix. Licenses are required for use. So, is this code public domain or not? The Acacia website is not really clear, they only claim they control patents about multi-dimensional barcodes (see http://www.acaciatechnologies.com/patentportfolio.htm#mul). --Antifumo 00:27, 6 March 2006 (UTC)Reply

The Acacia website is unclear probably because their patents are considered bogus by many (if not most) people in the industry. It is worthy to note that their patents don't mention or specifically describe Data Matrix. Instead they discuss 2D barcode concepts at a high level, and the company claims that Data Matrix overlaps the concepts taught by their patents. They have been sued over these claims in Minnesota District Court (http://isys.com/news/press_releases/2006/Trolling.asp), and if they lose then their patents may be rendered worthless. Regardless, the patents in question are set to expire in November 2007 (with no possibility of renewal) so it will become a non-issue after that. As for the Data Matrix standard, it was placed in the public domain by its inventor (which was not Acacia or the company it acquired the patents from), and remains there. However, the "royalty free" status is now challenged by Acacia's claims. You will see that many big companies have agreed to purchase a license from Acacia to avoid a patent infringement lawsuit, but this appears to a function of companies just wanting to get on with their core business. Mblaughton 16:52, 30 November 2006 (UTC)Reply

The following discussion is an archived debate of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the debate was moveMets501 (talk) 16:51, 4 November 2006 (UTC)Reply

Requested move edit

Data MatrixDatamatrix — 'Proposed move. New name is correct spelling for article (see above "Tools, specifications"). Data matrix and Data Matrix should redir to Matrix (mathematics). Dysmorodrepanis 01:04, 29 October 2006 (UTC) Dysmorodrepanis 01:04, 29 October 2006 (UTC)Reply

Survey edit

Add  * '''Support'''  or  * '''Oppose'''  on a new line followed by a brief explanation, then sign your opinion using ~~~~.

Discussion edit

Add any additional comments:

Data Matrix is the official ISO 16022 name while Datamatrix is the common name. It would be best to keep the official version of the spelling.

Concur; modified move request: Data matrix should redir to Matrix (mathematics) where a disambig should be included. The non-Capitalized term is commonly used in scientific statistics [1] and at present the proper article is not reachable by linking the term.
The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

More about the title edit

People have requested that discussion of the page title be reopened, so feel free to comment about what you think the title should be below. —Mets501 (talk) 03:03, 30 November 2006 (UTC)Reply

What is the need to move the article? The term "Datamatrix" applies to a certain type of barcode, the subject of this article. So what is the issue? ≈ jossi ≈ (talk) 03:42, 30 November 2006 (UTC)Reply

If there are similar names, we can create a disambiguation page. ≈ jossi ≈ (talk) 03:45, 30 November 2006 (UTC)Reply

I'm in favor of naming the article "Data Matrix" (two words) to be in agreement with the official name given and recognized by the ISO and AIM standards organizations. I see that "Datamatrix" (one word) is described above as "the common name" for this barcode symbology, but I have doubts about this claim. I think it would be more accurate to say that "Datamatrix" is one common name, but probably not the most common name and certainly not the official one. In my opinion there would need to be a very compelling reason to name it differently than the name given by its inventors. Granted, I'm relatively new to wikipedia, so I don't know all the conventions. Mblaughton 15:47, 30 November 2006 (UTC)Reply

I'm sorry, but this is not a barcode for the simple reason that it does not consist of bars. The very first line of the article is incorrect. The application is similar, but it's simply not a barcode of any sort, idiots! --80.223.57.250 (talk) 05:49, 27 September 2008 (UTC)Reply

datamatrix or dataglyph edit

is there any difference between a datamatrix and a dataglyph (or 2d barcode) or are these things all the same?

Hsp01 08:10, 4 April 2007 (UTC)Reply

  • These are two different symbols. There are a large number of two-dimensional "digital" codes, many of which may be called a "2D barcode". The constituent elements are different, and encoding is different as well. (Briefly: they look different, and work differently.) You should be able to google to find info about either. -Rethunk (talk) 00:49, 2 January 2008 (UTC)Reply

Example of Data Matrix code edit

There is an example of a Data Matrix code in the article. The text beneath states, that the code means "Wikipedia, the free encyclopedia". But I have a problem to verify this statement. I entered the example text on the page: Jaxo.com and the picture/Data Matrix which was generated was different from the one in the wikipedia article. Can anyone explain the difference between those two Data Matrix codes? Does anyone know the tool / website, which generated the picture in the article? --AircraftWorld (talk) 12:46, 28 January 2008 (UTC)Reply

 
An example of a Data Matrix code, encoding the text: "Wikipedia, the free encyclopedia"
I can't tell you how it was generated, but I've verified it with dmtxread (part of libdmtx), and it does indeed say: "Wikipedia, the free encyclopedia". CountingPine (talk) 14:02, 1 February 2008 (UTC)Reply

Indeed it really says what is written beneath. I just got confused in the first time, when I generated a Data Matrix based on the text and the results weren't the same. I guess the FEC may be different. --AircraftWorld (talk) 15:54, 1 February 2008 (UTC)Reply

I changed the 4x4 sample from random junk to Lorem Ipsum. No reason, I guess, just consistency. Anyway, I can't seem to get the caption AND size to work at the same time. If I use thumb or frame the size is ignored. If I don't the caption is ignored. What is the best way to do this? Padillah (talk) 15:33, 13 June 2008 (UTC)Reply

The difference in the generated symbols, for a given set of input data, may be accounted for by the use of different encodation modes. There are six possible compaction/encodation modes, and which mode is more efficient depends on the data to be encoded. In many cases, a combination of modes (with fragments of the input data being encoded using different modes, with mode switching between fragments) will lead to the most efficient encodation, in terms of generating the smallest symbol size.

The sample symbol in the article, which encodes the (short) 'lorem ipsum' text, has in fact been encoded using just the (default) 'ASCII' mode, resulting in a 48x48 module symbol. That text can be encoded more efficiently using 'Text' mode, resulting in a (smaller) 40x40 module symbol.DansDadUK (talk) 14:42, 14 November 2008 (UTC)Reply

There are actually more than 6 modes of Data Matrix encoding, however, only 6 were released by the patent holder (RVSI, Robotic Vision Systems, Inc. at the time) to the public domain to allow for International Standards inclusion (ISO/IEC and AIM Standards). Other versions use different error correction schemes and are still considered proprietary. Some applications, such as the use of Data Matrix to encode biometric information (including finger prints and photographs)for identification purposes,were never released to the public domain and still have patents in force regarding that use. All of the IP related to Data Matrix passed to Siemens AG upon its purchase of the assets of RVSI's Acuity CiMatrix Division in 2005 and subsequently to Microscan when it purchased the Division in September 2008.--JPJohn (talk) 20:52, 17 November 2008 (UTC) JPJohnReply

The glyph that results depends on what encoding type that was used. There are 6 currently for the data matrix format:
  • ASCII
  • TEXT
  • C40
  • BASE256
  • (ANSI) X12
  • EDIFACT
 
ASCII and TEXT are the most common formats. What encoding Datamatrix.svg is using I have no idea. It was impossible to find a free encoder for the last 2 formats. --Shandristhe azylean 23:00, 4 September 2010 (UTC)Reply
Interesting example. FYI, the original example used the TEXT encoding. You can tell by comparing the upper-left portion of the symbols, which is where the beginning of the message is stored. Bobmath (talk) 14:24, 19 July 2011 (UTC)Reply

The crop circle edit

Note that the "crop circle" data matrix in Germany is in fact referred to as a Semacode, not a Data Matrix. [1]

However, as the Semacode page is suggested for merge into this page anyway, I have not moved the "crop circle" reference.

93.104.198.2 (talk) 16:52, 22 September 2010 (UTC)Reply

References

Encoding section edit

I doubt that there will ever be a "WikiProject Data Matrix encoding", so I don't think the expert attention tag is being used correctly.

I have added information on the encoding methods used. It's sourced from the ISO spec, which is unfortunately not freely available. I don't know whether this level of detail is really wanted in the article, but similar information is provided in several of the other Barcode articles (such as Code 128).

Previously, I added a diagram showing the order of message placement within the symbol. The process depends on the exact size of the symbol, and there are a number of special cases that need to be taken into account. I could work on detailing that, but I'd like to know if other editors think it would be worthwhile. Bobmath (talk) 16:20, 4 October 2011 (UTC)Reply

Redundant Headings? edit

Having two headings "Applications" and "Data Matrix Applications" seems unnecessary. Their content should either be merged or one of the headings changed (the second seems specific to industrial engineering). Thoughts on possible cleanups? FaradayLupin (talk) 17:10, 3 October 2012 (UTC)Reply

Naming and capitalization edit

Why is this page at Data Matrix and not Data matrix (computer science)? Is "Data Matrix" a trademarked proprietary technology? If not, this page may be mis-titled per MOS:CAPS. Ibadibam (talk) 00:42, 26 October 2013 (UTC)Reply

Image queue edit

Error in diagram of corner case 2 edit

The byte order listed is backwards. The diagram starts counting at zero in the lower right hand corner of the upper right piece of the third 'i'. But that gives you a binary pattern of 01010110 which = 86 which = 85+1 where ASCII 85 is 'U'.

It should start in the top square of the lower left piece. This gives a binary pattern of 01101010 which = 106 which = 105+1 where ASCII 105 is 'i'.

It's also possible that the diagram example really spells "WikipedUa", but I checked against a different diagram, and my order works there too. — Preceding unsigned comment added by 12.228.187.10 (talk) 17:44, 25 February 2016