Specifies the encoding scheme to be used to convert binary image data to the text format when saving raster image into the PDF document. Used with PDF filter TEXT_ENCODING control parameter.

Values:

IG_PDF_TEXTENC_NONE	Specifies that no encoding will be used.
IG_PDF_TEXTENC_ASCII_85	Specifies that ASCII 85 encoding will be used.
IG_PDF_TEXTENC_ASCII_HEX	Specifies that ASCII HEX encoding will be used.