I need to create DataMatrix barcodes which may contain non-Latin characters. I have code which creates the barcodes correctly when they only consist of Latin characters; when I run the same code with non-Latin (Hebrew or Russian) characters, however, although the code runs to completion and the barcode is created, the non-Latin characters are not deciphered by the barcode reader.
Any assistance or ideas would be greatly appreciated!
Your issue is related to the character encoding used prior to generating the barcode. The encoding used by the generator to encode must match the encoding used by the reader to decode.
Possible encodings are:
Extended Channel Interpretations (ECI) is supported by DataMatrix and other 2D barcode standards. The generator places an ECI identifying code inside the barcode data, so the reader knows to use ECI to correctly convert the data back to text.
UTF-8 encodes pretty much any language.
Code page is an older encoding, but if your generator is using it, you can use 1255 for Hebrew code page or 1251 for Russian code page. See this SO answer for more info.
To test your encoding, try Inlite's Online Barcode Reader (OBR) which should read the correct text for ECI and UTF-8 encoded barcodes. If it does, the problem is with your barcode reader which is not decoding correctly.
If OBR returns binary data, either your generator uses code page or does not encode correctly at all. Try another generator that supports ECI or UTF-8.
Related
I am attempting to analyze a corpus of tweets extracted from Twitter. A number of tweets appear in non-UTF characters.
For example, one tweet is: "［米国］一人㠮ワクムン未接種ã ®åÂ\ 㠩も㠋ら広ã ΋ £ã Ÿéº»ç–¹ã€ 㠮教訓。 #ShotbyShotorg: How one unvaccinated child sparked Minnesota measles outbreak \"
I am not familiar with these non-alphanumeric characters or how to convert/exclude these characters. Are these garbage characters or do they need to be converted? Thank you.
I found the original tweet: https://twitter.com/narumita/status/476295179796611072?s=21. From this tweet it’s quite clear that the “garbage” text was supposed to be Japanese.
The original text reads
［米国］一人のワクチン未接種の子どもから広がった麻疹、の教訓。
Somehow, your text has undergone two rounds of mojibake-ification: it was encoded as UTF-8, decoded as Windows Code Page 1252 (CP-1252), encoded as UTF-8 again, and decoded as CP-1252 again. Unfortunately the text is not recoverable from what you posted since the CP-1252 encoding cannot fully decode all UTF-8 bytes. However, a quick Python script recovers a couple characters, enough to confirm this is how it was corrupted:
t = '［米国］一人㠮ワクムン未接種ã ®åÂ\ 㠩も㠋ら広ã ΋ £ã Ÿéº»ç–¹ã€ 㠮教訓。'
print(t.encode('cp1252', errors='replace').decode('utf8', errors='replace').encode('cp1252', errors='replace').decode('utf8', errors='replace'))
This outputs:
［米国］一人� �ワク� ン未接種� ��\ � �も� �ら広� �� �� �麻疹� � �教訓。
EDITED: A round-trip analysis (taking the original text and badly encoding it twice) revealed that it was likely using CP-1252, rather than ISO-8859-1; the encodings are identical on most codepoints. The post has been edited to use CP-1252 instead.
I'm having an encoding problem related to cookies on one of my websites.
A user is inputing Usuário, which has an acute accent, and that's being put in a cookie. The raw HEX for the cookie response is (for the Usuário string):
55 73 75 C3 A1 72 69 6F
When I see it in the browser, it looks like this:
...which is really messy. I need to fix this up.
Then I went to this website: http://www.rapidtables.com/convert/number/hex-to-ascii.htm and converted the HEX value to see how it would look like. And I got the same output:
Right. This means the HEX code is wrong. Then I tried to convert Usuário to ASCII to see how it should be. I used this WebSite: http://www.asciitohex.com/ and this is the result:
For my surprise, the HEX is exactly the one that is showing up messy. Why???
And how do I represent Usuário in ASCII so I can put it in a cookie? Should I manually encode it?
PS: I'm using ASP.NET, just in case it matters.
As of 2015 the standard of the web to store character data is UTF-8 and not ASCII. ASCII actually only contains the first 128 characters of the codepage, and does not include any kind of accented characters. To add accented characters to this 128 characters there were many legacy solutions: codepages. They each added 128 different characters to the default ASCII list thereby allowing representing 256 different characters.
The problem was, that this didn't properly solve the issue: ASCII based codepages were more or less incomatible with each other (except for the first 128 characters), and there was usually no way of programatically knowing which codepage was in used.
One of the solutions was UTF-8, which is a way to encode the unocde character set (containing most of the characters used around the world, and more) while trying to remain compatible with ASCII. The first 128 characters are actually the same in both cases, but afterwards UTF-8 characters become multi-byte: one character is encoded using a series of bytes (usually 2-3, depends on which character needs to be encoded)
The problem is if you are using some kind of ASCII based single byte codebase (like ISO-8859-1), which encodes supported characters in single bytes, but your input is actually UTF-8, which will encode accented characters in multiple bytes (you can see this in your HEX example. á is encoded as C3 A1: two bytes). If you try to read these two bytes in an ASCII based codepage, which uses single bytes for every characters (in West-Europe this codepage is usually ISO-8859-1), then each of this two bytes will be reprensented with two different characters.
In the web world the default encoding is UTF-8, so your clients will usually send their requests using UTF-8. ASP.NET is Unicode aware, so it can handle these requests. However somewere in your code this UTF-8 is converted acccidentally into ISO-8859-1, and then back into UTF-8. This might happen on various layers. As you have issues it probably happens at the cookie layer, which is sometimes problematic (here is how it worked in 2009). You should also double check your application that it uses UTF-8 everywhere else though (views, database, etc.), if you want to properly support accented characters.
When I read in csv files to r the requesting dataframe has very different dimensions than I see when I open the file in excel or notepad and the column heading is labeled as "ÿþA". What does this mean?
thanks,
The file you are reading is using an UTF-16 or UTF-32 encoding (with a BOM), and the r read.csv function has not been informed correctly.
As Karsten suggests you should use the fileEncoding parameter to specify the correct encoding, which I suspect should be "UTF-16LE".
Here is what the R Studio documentation states about encoding:
Encoding
The encoding of the input/output stream of a connection can be specified by name in the same way as it would be given to iconv: see that help page for how to find out what encoding names are recognized on your platform. Additionally, "" and "native.enc" both mean the ‘native’ encoding, that is the internal encoding of the current locale and hence no translation is done.
Re-encoding only works for connections in text mode: reading from a connection with re-encoding specified in binary mode will read the stream of bytes, but mixing text and binary mode reads (e.g. mixing calls to readLines and readChar) is likely to lead to incorrect results.
The encodings "UCS-2LE" and "UTF-16LE" are treated specially, as they are appropriate values for Windows ‘Unicode’ text files. If the first two bytes are the Byte Order Mark 0xFFFE then these are removed as some implementations of iconv do not accept BOMs. Note that whereas most implementations will handle BOMs using encoding "UCS-2" and choose the appropriate byte order, some (including earlier versions of glibc) will not. There is a subtle distinction between "UTF-16" and "UCS-2" (see http://en.wikipedia.org/wiki/UTF-16/UCS-2: the use of surrogate pairs is very rare so "UCS-2LE" is an appropriate first choice.
As from R 3.0.0 the encoding "UTF-8-BOM" is accepted for reading and will remove a Byte Order Mark if present (which it often is for files and webpages generated by Microsoft applications). If it is required (it is not recommended) when writing it should be written explicitly, e.g. by writeChar("\ufeff", con, eos = NULL) or writeBin(as.raw(c(0xef, 0xbb, 0xff)), binary_con)
Requesting a conversion that is not supported is an error, reported when the connection is opened. Exactly what happens when the requested translation cannot be done for invalid input is in general undocumented. On output the result is likely to be that up to the error, with a warning. On input, it will most likely be all or some of the input up to the error.
It may be possible to deduce the current native encoding from Sys.getlocale("LC_CTYPE"), but not all OSes record it.
And here is what Wiki states on the BOM:
Byte order mark
The byte order mark (BOM) is a Unicode character used to signal the endianness (byte order) of a text file or stream. It is encoded at U+FEFF byte order mark (BOM). BOM use is optional, and, if used, should appear at the start of the text stream. Beyond its specific use as a byte-order indicator, the BOM character may also indicate which of the several Unicode representations the text is encoded in.1
Because Unicode can be encoded as 16-bit or 32-bit integers, a computer receiving these encodings from arbitrary sources needs to know which byte order the integers are encoded in. The BOM gives the producer of the text a way to describe the text stream's endianness to the consumer of the text without requiring some contract or metadata outside of the text stream itself. Once the receiving computer has consumed the text stream, it presumably processes the characters in its own native byte order and no longer needs the BOM. Hence the need for a BOM arises in the context of text interchange, rather than in normal text processing within a closed environment.
I was trying to find a solution for my problem and after looking at the forums I couldn't so I'll explain my problem here.
We receive a csv file from a client with some special characters and encoded as unknown-8bit. We convert this csv file to xml using an awk script. With the xml file we make an API call to our system using utf-8 as default encoding. The response is an error with following information:
org.apache.xerces.impl.io.MalformedByteSequenceException: Invalid byte 1 of 1-byte UTF-8 sequence
The content of the file is as bellow:
151215901579-109617744500,sandra,sandra,Coesfeld,,Coesfeld,48653,DE,1,2.30,ASTRA 16V CAVALIER CALIBRA TURBO BLUE 10,53.82,GB,,.80,3,ASTRA 16V CAVALIER CALIBRA TURBO BLUE 10MM 4CORE IGNITION HT LEADS WIRES MLR.CR,,sandra#online.de,parcel1,Invalid Request,,%004865315500320004648880276,INTL,%004865315500320004648880276,1,INTL,DPD,180380,INTL,2.30,Send A2B Ltd,4th Floor,200 Gray’s Inn Road,LONDON,,WC1X8XZ,GBR,
I think the problem is in the field "200 Gray’s Inn Road" cause when I use utf-8 encoding it automatically converts "'" character by a x92 value.
Does anybody know how can I handle this?
Thanks in advance,
Sandra
Find out the actual encoding first, best would be asking the sender.
If you cannot do so, and also for sanity-checking, the unix command file is very useful for that (the linked page shows more options).
Next step, convert to UTF-8.
As it is obviously an ASCII-based encoding, you could just discard all non-ASCII or replace them on encoding, if that loss is acceptable.
As an alternative, open it in the editor of your choice and flip the encoding used for interpreting the data until you get something useful. My guess is you'll have either Latin-1 or Windows-1252, but check it for yourself.
Last step, do what you wanted to do, in comforting knowledge that you now have valid UTF-8.
Obviously, don't pretend it's UTF-8 if it isn't. Find out what the encoding is, or replace all non-ASCII characters with the UTF-8 REPLACEMENT CHARACTER sequence 0xEF 0xBF 0xBD.
Since you are able to view this particular sample just fine, you apparently already know which encoding it is (even if you don't know that you know -- it would be whatever your current set-up is using) -- I would guess Windows-1252 which uses 0x92 for a curvy right single quote.
I have a list of character that display fine in WebBrowser in the form of encoded characters such as ...
But when posting these characters onto server to I realized that HttpUtility.HtmlDecode cannot convert them to characters as browser did, they all become space.
text = System.Web.HttpUtility.HtmlDecode("");
I expect it to return € but it return space instead. The same thing happen for some other characters as well.
Does anyone know how to fix this or any workaround?
This is commonly result of using literal values and mixing UTF-8 and ASCII. In UTF-8 euro sign is encoded as 3 bytes so there is no ASCII counterpart for it.
Update
Your code is illegal if you are using UTF-8 since it only supports the first 128 characters and the rest are encoded is multiple bytes. You need to use the Unicode syntax:
// !!! NOT HtmlDecode!!!
text = System.Web.HttpUtility.UrlDecode("%E2%82%AC");
UPDATE
OK, I have left the code as it was but added the comment that it does not work. It does not work because it is not an encoding which is of concern for HTML - it is not an HTML. This is of concern for the URL and as such you need to use UrlDecode instead.
ASCII is 7-Bit; there are no characters 128 through 255. The MSDN article you linked is following the long tradition of pretending ASCII is 8-Bit; the article actually shows code page 437.
I'm not sure why you're not simply writing € (compatibility?), but € or € should do, too.
You typically want to do something like:
string html = ""
string trash = WebUtility.HtmlDecode(html);
//Convert from default encoding to UTF8
byte[] bytes = Encoding.Default.GetBytes(trash);
string proper = Encoding.UTF8.GetString(bytes);