PDFlib 8 Windows COM/.NET Tutorial

4.3 Chinese, Japanese, and Korean Encodings
Historically, a wide variety of CJK encoding schemes have been developed by diverse
standards bodies and companies. Fortunately, all prevalent encodings are supported by
Acrobat and PDF by default. Since the concept of an encoding is much more complicated
for CJK text than for Latin text, simple 8-bit encodings no longer suffice. Instead,
PostScript and PDF use the concept of character collections and character maps (CMaps)
for organizing the characters in a font.
Predefined CMaps for common CJK encodings. The predefined CJK CMaps are listed in
Table 4.3. As can be seen from the table, they support most CJK encodings used on Mac,
Windows, and Unix systems, as well as several vendor-specific encodings, e.g. Shift-JIS,
EUC, and ISO 2022 for Japanese, GB and Big5 for Chinese, and KSC for Korean. Unicode is
supported for all locales as well.
Table 4.3 Predefined CMaps for Japanese, Chinese, and Korean text (from the PDF Reference)
locale CMap name character set and text format
Simplified
Chinese
Traditional
Chinese
UniGB-UCS2-H
UniGB-UCS2-V
UniGB-UTF16-H
UniGB-UTF16-V
UniCNS-UCS2-H
UniCNS-UCS2-V
UniCNS-UTF16-H
UniCNS-UTF16-V
Unicode (UCS-2) encoding for the Adobe-GB1 character collection
Unicode (UTF-16BE) encoding for the Adobe-GB1 character collection. Contains
mappings for all characters in the GB18030-2000 character set.
Unicode (UCS-2) encoding for the Adobe-CNS1 character collection
Unicode (UTF-16BE) encoding for the Adobe-CNS1 character collection. Contains
mappings for all of HKSCS-2001 (2- and 4-byte character codes)
Japanese UniJIS-UCS2-H, -V Unicode (UCS-2) encoding for the Adobe-Japan1 character collection
UniJIS-UCS2-HW-H
UniJIS-UCS2-HW-V
UniJIS-UTF16-H
UniJIS-UTF16-V
Same as UniJIS-UCS2-H, but replaces proportional Latin characters with halfwidth
forms
Unicode (UTF-16BE) encoding for the Adobe-Japan1 character collection. Contains
mappings for all characters in the JIS X 0213:1000 character set.
Korean UniKS-UCS2-H, -V Unicode (UCS-2) encoding for the Adobe-Korea1 character collection
UniKS-UTF16-H, -V Unicode (UTF-16BE) encoding for the Adobe-Korea1 character collection
Note Unicode-aware language bindings support only Unicode CMaps (UCS2 or UTF16). Other CMaps
can not be used (see Section 4.4.2, »Strings in Unicode-aware Language Bindings«, page 109).
CJK text encoding for standard CMaps. The client is responsible for supplying text encoded
such that it matches the requested CMap. PDFlib checks whether the supplied
text conforms to the requested CMap, and will raise an exception for bad text input
which doesn’t conform to the selected CMap.
CMap configuration. In order to create Chinese, Japanese, or Korean (CJK) text output
with one of the predefined CMaps PDFlib requires the corresponding CMap files for processing
the incoming text and mapping CJK encodings to Unicode. The CMap files are
available in a separate package. They should be installed as follows:
> On Windows the CMap files will be found automatically if you place them in the
resource/cmap directory within the PDFlib installation directory.
> On other systems you can place the CMap files at any convenient directory, and
must manually configure the CMap files by setting the SearchPath at runtime:
104 Chapter 4: Unicode and Legacy Encodings (Edition for COM, .NET, and REALbasic)