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         CHAPTER 5                                                                       Text



         Note: If an application producing a PDF file encounters text to be included that
         uses CIDs from a higher-numbered supplement than the one corresponding to the
         PDF version being generated, the application should embed the CMap for the
         higher-numbered supplement rather than refer to the predefined CMap (see the
         next section).

         The CMap programs that define the predefined CMaps are available through the
         ASN Web site and are also provided in conjunction with the book CJKV Informa-
         tion Processing by Ken Lunde. Details on the character collections, including sam-
         ple glyphs for all the CIDs, can be found in a number of Adobe Technical Notes.
         For more information about these Notes and the aforementioned book, see the
         Bibliography.


         Embedded CMap Files

         For character encodings that are not predefined, the PDF file must contain a
         stream that defines the CMap. In addition to the standard entries for streams
         (listed in Table 3.4 on page 62), the CMap stream dictionary contains the entries
         listed in Table 5.17. The data in the stream defines the mapping from character
         codes to a font number and a character selector. The data must follow the syntax
         defined in Adobe Technical Note #5014, Adobe CMap and CIDFont Files Specifi-
         cation.

                         TABLE 5.17 Additional entries in a CMap dictionary
KEY             TYPE          VALUE

Type            name          (Required) The type of PDF object that this dictionary describes; must be
                              CMap for a CMap dictionary. (Although this object is the value of an entry
                              named Encoding in a Type 0 font, its type is CMap.)

CMapName        name          (Required) The PostScript name of the CMap. It should be the same as the
                              value of CMapName in the CMap file.

CIDSystemInfo   dictionary    (Required) A dictionary (see Section 5.6.2, “CIDSystemInfo Dictionaries”)
                              containing entries that define the character collection for the CIDFont or
                              CIDFonts associated with the CMap.
                              The value of this entry should be the same as the value of CIDSystemInfo in
                              the CMap file. (However, it does not need to match the values of
                              CIDSystemInfo for the Identity-H or Identity-V CMaps.)

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