How to determine encoding table of a text file - text

I have .txt and .java files and I don't know how to determine the encoding table of the files (Unicode, UTF-8, ISO-8525, …). Does there exist any program to determine the file encoding or to see the encoding?

If you're on Linux, try file -i filename.txt.
$ file -i vol34.tex
vol34.tex: text/x-tex; charset=us-ascii
For reference, here is my environment:
$ which file
/usr/bin/file
$ file --version
file-5.09
magic file from /etc/magic:/usr/share/misc/magic
Some file versions (e.g. file-5.04 on OS X/macOS) have slightly different command-line switches:
$ file -I vol34.tex
vol34.tex: text/x-tex; charset=us-ascii
$ file --mime vol34.tex
vol34.tex: text/x-tex; charset=us-ascii
Also, have a look here.

Open the file with Notepad++ and will see on the right down corner the encoding table name. And in the menu encoding you can change the encoding table and save the file.

You can't reliably detect the encoding from a textfile - what you can do is make an
educated guess by searching for a non-ascii char and trying to determine if it is a
unicode combination that makes sens in the languages you are parsing.

See this question and the selected answer. There’s no sure-fire way of doing it. At most, you can rule things out. The UTF encodings you’re unlikely to get false positives on, but the 8-bit encodings are tough, especially if you don’t know the starting language. No tool out there currently handles all the common 8-bit encodings from Macs, Windows, Unix, but the selected answer provides an algorithmic approach that should work adequately for a certain subset of encodings.

In a text file there is no header that saves the encoding or so. You can try the linux/unix command find which tries to guess the encoding:
file -i unreadablefile.txt
or on some systems
file -I unreadablefile.txt
But that often gives you text/plain; charset=iso-8859-1 although the file is unreadable (cryptic glyphs).
This is what I did to find the correct file encoding for an unreadable file and then translate it to utf8 was, after installing iconv. First I tried all encodings, displaying (grep) a line that contained the word www. (a website address):
for ENCODING in $(iconv -l); do echo -n "$ENCODING "; iconv -f $ENCODING -t utf-8 unreadablefile.txt 2>/dev/null| grep 'www'; done | less
This last commandline shows the the tested file encoding and then the translated/transcoded line.
There were some lines which showed readable and consistent (one language at a time) results. I tried manually some of them, for example:
ENCODING=WINDOWS-936; iconv -f $ENCODING -t utf-8 unreadablefile.txt -o test_with_${ENCODING}.txt
In my case it was a chinese windows encoding, which is now readable (if you know chinese).

Does there exist any program to determine the file encoding or to see the encoding?
This question is 10 years old as I write this, and the answer is still, "No" - at least not reliably. There's not been much improvement unfortunately. My recent experience suggests the file -I command is very much "hit-or-miss". For example, when checking a text file on macOS 10.15.6:
% file -i somefile.asc
somefile.asc: application/octet-stream; charset=binary
somefile.asc was a text file. All charcters in it were encoded in UTF-16 Little Endian. How did I know this? I used BBedit - a competent text editor. Determining the encoding used in a file is certainly a tough problem, but...?

if you are using python, the chardet package is a good option, for example
from chardet.universaldetector import UniversalDetector
files = ['a-1.txt','a-2.txt']
detector = UniversalDetector()
for filename in files:
print(filename.ljust(20), end='')
detector.reset()
for line in open(filename, 'rb'):
detector.feed(line)
if detector.done: break
detector.close()
print(detector.result)
gives me as a result:
a-1.txt {'encoding': 'Windows-1252', 'confidence': 0.7255358182877111, 'language': ''}
a-2.txt {'encoding': 'utf-8', 'confidence': 0.99, 'language': ''}

Related

iconv command is not changing the encoding of a plain text file to another encoding

In Linux I created a plain text file. using "file -i" I am seeing file encoding is "us-ascii" . After trying below commands it is still showing output file encoding as "us-ascii". Could you please tell me how to change encoding? or Is there any way to download some encoded file which I can't read.
iconv -f US-ASCII -t ISO88592//TRANSLIT -o o.txt ip.txt
iconv -f UTF-8 -t ISO-8859-1//TRANSLIT -o op.txt ip.txt
I am expecting either iconv change the encoding or I can download some encoded file.
If your file contains only ASCII character, then there's no difference between the ASCII, UTF-8 and different ISO8859-x encoding. So after conversion, you will end up with the exactly same file.
A text file does not store any information about what encoding was used. Therefore, the file applies a few rules but at the end of the day, it's just a guess. And as the files are identical, the result will alwazys be the same.
To see a difference, you will must use characters that are encoded differently with the different encoding or are not avaialbe at all in one of the encodings, e.g. ă, € or 😊.

Convert files between UTF-8 and ISO-8859 on Linux

Every time that I get confronted with Unicode, nothing works. I'm on Linux, and I got these files from Windows:
$file *
file1: UTF-8 Unicode text
file2: ISO-8859 text
file3: ISO-8859 text
Nothing was working until I found out that the files have different encodings. I want to make my life easy and have them all in the same format:
iconv -f UTF-8 -t ISO-8859 file1 > test
iconv: conversion to `ISO-8859' is not supported
Try `iconv --help' or `iconv --usage' for more information.
I tried to convert to ISO because that's only 1 conversion + when I open those ISO files in gedit, the German letter "ü" is displayed just fine. Okay, next try:
iconv -f ISO-8859 -t UTF-8 file2 > test
iconv: conversion from `ISO-8859' is not supported
Try `iconv --help' or `iconv --usage' for more information.
but obviously that didn't work.
ISO-8859-x (Latin-1) encoding only contains very limited characters, you should always try to encode to UTF-8 to make life easier.
And utf-8 (Unicode) is a superset of ISO 8859 so it will be not surprised you could not convert UTF-8 to ISO 8859
It seems command file just give a very limited info of the file encoding
You could try to guess the from encoding either ISO-8859-1 or ISO-8859-15 or the other from 2~14 as suggested in the comment by #hobbs
And you could get a supported encoding of iconv by iconv -l
If life treats you not easy with guessing the real file encoding, this silly script might help you out :D
As in other answers, you can list out the supported formats
iconv -l | grep 8859
A grep will save your time to find which version of your encoding is/are supported. You can provide the <number> as in my example or ISO or any expected string in your encoding.

How to remove non UTF-8 characters from text file

I have a bunch of Arabic, English, Russian files which are encoded in utf-8. Trying to process these files using a Perl script, I get this error:
Malformed UTF-8 character (fatal)
Manually checking the content of these files, I found some strange characters in them.
Now I'm looking for a way to automatically remove these characters from the files.
Is there anyway to do it?
This command:
iconv -f utf-8 -t utf-8 -c file.txt
will clean up your UTF-8 file, skipping all the invalid characters.
-f is the source format
-t the target format
-c skips any invalid sequence
Your method must read byte by byte and fully understand and appreciate the byte wise construction of characters. The simplest method is to use an editor which will read anything but only output UTF-8 characters. Textpad is one choice.
iconv
can do it
iconv -f cp1252 foo.txt
None of the methods here or on any other similar questions worked for me.
In the end what worked was simply opening the file in Sublime Text 2. Go to File > Reopen with Encoding > UTF-8. Copy the entire content of the file into a new file and save it.
May not be the expected solution but putting this out here in case it helps anyone, since I've been struggling for hours with this.

encoding problem?

i work with txt files, and i recently found e.g. these characters in a few of them:
http://pastebin.com/raw.php?i=Bdj6J3f4
what could these characters be? wrong character-encoding? i just want to use normal UTF-8 TXT files, but when i use:
iconv -t UTF-8 input.txt > output.txt
it's still the same.
When i open the files in gedit, copy+paste them in another txt files, then there's no characters like in the ones in pastebin. so gedit can solve this problem, it encodes the TXT files well. but there are too many txt files.
why are there http://pastebin.com/raw.php?i=Bdj6J3f4 -like chars in the text files? can they be converted to "normal chars"? I can't see e.g.: the "Ì" char, when i open the files with vim, only after i "work with them" (e.g.: awk, etc)
It would help if you posted the actual binary content of your file (perhaps by using the output of od -t x1). The pastebin returns this as HTML:
"Ì"
"Ã"
"é"
The first line corresponds to U+00C3 U+0152. THe last line corresponds to U+00C3 U+00A9, which is the string "\ux00e9" in UTF ("\xc3\xa9") with the UTF-8 bytes reinterpreted as Latin-1.
From man iconv:
The iconv program converts text from
one encoding to another encoding. More
precisely, it converts from the
encoding given for the -f option to
the encoding given for the -t option.
Either of these encodings defaults to
the encoding of the current locale
Because you didn't specify the -f option it assumes the file is encoded with your current locale's encoding (probably UTF-8), which apparently is not true. Your text editors (gedit, vim) do some encoding detection - you can check which encoding do they detect (I don't know how - I don't use any of them) and use that as -f iconv option (or save the open file with your desired encoding using one of those text editors).
You can also use some tool for encoding detection like Python chardet module:
$ python -c "import chardet as c; print c.detect(open('file.txt').read(4096))"
{'confidence': 0.7331842298102511, 'encoding': 'ISO-8859-2'}
..solved !
how:
i just right clicked on the folders containing the TXT files, and pasted them to another folder.. :O and presto..theres no more ugly chars..

How to tell binary from text files in linux

The linux file command does a very good job in recognising file types and gives very fine-grained results. The diff tool is able to tell binary files from text files, producing a different output.
Is there a way to tell binary files form text files? All I want is a yes/no answer whether a given file is binary. Because it's difficult to define binary, let's say I want to know if diff will attempt a text-based comparison.
To clarify the question: I do not care if it's ASCII text or XML as long as it's text. Also, I do not want to differentiate between MP3 and JPEG files, as they're all binary.
file is still the command you want. Any file that is text (according to its heuristics) will include the word "text" in the output of file; anything that is binary will not include the word "text".
If you don't agree with the heuristics that file uses to determine text vs. not-text, then the question needs to be better specified, since text vs. non-text is an inherently vague question. For example, file does not identify a PGP public key block in ASCII as "text", but you might (since it is composed only of printable characters, even though it is not human-readable).
The diff manual specifies that
diff determines whether a file is text
or binary by checking the first few
bytes in the file; the exact number of
bytes is system dependent, but it is
typically several thousand. If every
byte in that part of the file is
non-null, diff considers the file to
be text; otherwise it considers the
file to be binary.
A quick-and-dirty way is to look for a NUL character (a zero byte) in the first K or two of the file. As long as you're not worried about UTF-16 or UTF-32, no text file should ever contain a NUL.
Update: According to the diff manual, this is exactly what diff does.
This approach defers to the grep command in determining whether a file is binary or text:
is_text_file() { grep -qIF '' "$1"; }
grep options used:
-q Quiet; Exit immediately with zero status if any match is found
-I Process a binary file as if it did not contain matching data
-F Interpret PATTERNS as fixed strings, not regular expressions.
grep pattern used:
'' Empty string. All files (except an empty file)
will match this pattern.
Notes
An empty file is not considered a text file according to this test. (The GNU file command agrees with this assessment.)
A file with one printable character, say a, is considered a text file according to this test. (Makes sense to me.) (The file command disagrees with this assessment. (Tested with GNU file))
This approach requires only one child process to test whether a file is text or binary.
Test
# cd into a temp directory
cd "$(mktemp -d)"
# Create 3 corner-case test files
touch empty_file # An empty file
echo -n a >one_byte_a # A file containing just `a`
echo a >one_line_a # A file containing just `a` and a newline
# Another test case: a 96KiB text file that ends with a NUL
head -c 98303 /usr/share/dict/words > file_with_a_null_96KiB
dd if=/dev/zero bs=1 count=1 >> file_with_a_null_96KiB
# Last test case: a 96KiB text file plus a NUL added at the end
head -c 98304 /usr/share/dict/words > file_with_a_null_96KiB_plus1
dd if=/dev/zero bs=1 count=1 >> file_with_a_null_96KiB_plus1
# Defer to grep to determine if a file is a text file
is_text_file() { grep -qI '^' "$1"; }
# Test harness
do_test() {
printf '%22s ... ' "$1"
if is_text_file "$1"; then
echo "is a text file"
else
echo "is a binary file"
fi
}
# Test each of our test cases
do_test empty_file
do_test one_byte_a
do_test one_line_a
do_test file_with_a_null_96KiB
do_test file_with_a_null_96KiB_plus1
Output
empty_file ... is a binary file
one_byte_a ... is a text file
one_line_a ... is a text file
file_with_a_null_96KiB ... is a binary file
file_with_a_null_96KiB_plus1 ... is a text file
On my machine, it seems grep checks the first 96 KiB of a file for a NUL. (Tested with GNU grep). The exact crossover point depends on your machine's page size.
Relevant source code: https://git.savannah.gnu.org/cgit/grep.git/tree/src/grep.c?h=v3.6#n1550
You could try to give a
strings yourfile
command and compare the size of the results with the file size ... i'm not totally sure, but if they are the same the file is really a text file.
These days the term "text file" is ambiguous, because a text file can be encoded in ASCII, ISO-8859-*, UTF-8, UTF-16, UTF-32 and so on.
See here for how Subversion does it.
A fast way to do this in ubuntu is use nautilus in the "list" view. The type column will show you if its text or binary
Commands like less, grep detect it quite easily(and fast). You can have a look at their source.

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