SECTION 4.8
343
Images
KEY
TYPE
VALUE
OC
dictionary
(Optional; PDF 1.5)
An optional content group or optional content mem-
bership dictionary (see Section 4.10, “Optional Content”), specifying the
optional content properties for this image XObject. Before the image is
processed, its visibility is determined based on this entry. If it is deter-
mined to be invisible, the entire image is skipped, as if there were no
Do
operator to invoke it.
sample in the
DeviceGray
color space. It paints the image on a page with its lower-
left corner positioned at coordinates (45, 140) in current user space and scaled to
a width and height of 132 user space units.
Example 4.28
20 0 obj
<< /Type /Page
/Parent 1 0 R
/Resources 21 0 R
/MediaBox [ 0 0 612 792 ]
/Contents 23 0 R
>>
endobj
21 0 obj
<< /ProcSet [ /PDF /ImageB ]
/XObject << /Im1 22 0 R >>
>>
endobj
22 0 obj
<< /Type /XObject
/Subtype /Image
/Width 256
/Height 256
/ColorSpace /DeviceGray
/BitsPerComponent 8
/Length 83183
/Filter /ASCII85Decode
>>
% Page object
% Resource dictionary for page
% Image XObject