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           SECTION 5.8                                                   Embed ded Font Programs



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      5.8 Embedded Font Programs

           A font program can be embedded in a PDF file as data contained in a PDF stream
           object. Such a stream object is also called a font file by analogy with font programs
           that are available from sources external to the consumer application. (See also
           implementation note 69 in Appendix H.)

           Font programs are subject to copyright, and the copyright owner may impose
           conditions under which a font program can be used. These permissions are re-
           corded either in the font program or as part of a separate license. One of the con-
           ditions may be that the font program cannot be embedded, in which case it
           should not be incorporated into a PDF file. A font program may allow embed-
           ding for the sole purpose of viewing and printing the document but not for creat-
           ing new or modified text that uses the font (in either the same document or other
           documents). The latter operation would require the user performing the opera-
           tion to have a licensed copy of the font program, not a copy extracted from the
           PDF file. In the absence of explicit information to the contrary, a PDF consumer
           should assume that any embedded font programs are to be used only to view and
           print the document and not for any other purposes.

           Table 5.23 summarizes the ways in which font programs are embedded in a PDF
           file, depending on the representation of the font program. The key is the name
           used in the font descriptor to refer to the font file stream; the subtype is the value
           of the Subtype key, if present, in the font file stream dictionary. Further details of
           specific font program representations are given below.

                        TABLE 5.23 Embedded font organization for various font types
KEY              SUBTYPE             DESCRIPTION

FontFile         —                   Type 1 font program, in the original (noncompact) format described in
                                     Adobe Type 1 Font Format. This entry can appear in the font descriptor for
                                     a Type1 or MMType1 font dictionary.

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