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Converting two byte encoding to UTF-8

2 messages · Duncan Murdoch

Duncan Murdoch
# 
I have a file that includes Japanese characters encoded using the 
"JIS_X0208-1997" encoding.  According to iconvlist(), an earlier 
revision "JIS_X0208-1990" is supported, so I'd like to try that to 
decode them.

However, I can't seem to find how to provide input to iconv() to do it. 
This is a two-byte encoding, so one character has bytes

 > as.raw(result[[1]]$kanji)
[1] b0 a1

But this is being interpreted as two characters by iconv():

 > iconv(as.raw(result[[1]]$kanji), from = "JIS_X0208-1990", to = "UTF-8")
[1] "?" "?"

I can't seem to find any input that iconv() will accept to treat this as 
a single character.  (I believe the answer should be ? , if that helps.) 
  How do I tell it to use 0xb0a1 (or 0xa1b0, if that's the right byte 
order)?  I just see NA:

 >  iconv(0xb0a1, from = "JIS_X0208-1990", to = "UTF-8")
[1] NA
 > iconv(0xa1b0, from = "JIS_X0208-1990", to = "UTF-8")
[1] NA

Duncan Murdoch
Duncan Murdoch
# 
I have solved it!

First, the bytes I have are offset by 0x80 from what they should 
contain.  The actual encoding of ? is 0x30 0x21.  But subtracting 0x80 
isn't enough; they are still treated as two characters:

 > iconv(as.raw(result[[1]]$kanji-0x80), from = "JIS_X0208-1990", 
to="UTF-8")
[1] "?" "?"

However, if I put those bytes in a list entry, it works:

 > iconv(list(as.raw(result[[1]]$kanji-0x80)), from = "JIS_X0208-1990", 
to="UTF-8")
[1] "?"

Duncan Murdoch
On 19/03/2022 6:52 a.m., Duncan Murdoch wrote: