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Adobe Acrobat SDK
Adobe® Supplement to the ISO 32000
Modify Table 3.18 as shown below where only entries that changed are listed in the table. The
value of 5; the only change to the other listed entries (
. Unchanged text is shown in gray.
5
KEY
V
StmF
TABLE 3.18 Entries common to all encryption dictionaries
TYPE
DESCRIPTION
number
(Optional but strongly recommended) A code specifying the algorithm to
be used in encrypting and decrypting the document:
, An algorithm that is undocumented and no longer supported, and
0
whose use is strongly discouraged.
no new files should be written using 0.
, Algorithm 3.1 on page 119, with an encryption key length of 40
1
bits; see below.
, (PDF 1.4) Algorithm 3.1, but permitting encryption key lengths
2
greater than 40 bits.
, (PDF 1.4) An unpublished algorithm that permits encryption key
3
lengths ranging from 40 to 128 bits; see implementation note 22 in
Appendix H.
, (PDF 1.5) The security handler defines the use of encryption and
4
decryption in the document, using the rules specified by the
StmF
bits.
5, (ExtensionLevel 3) The security handler defines the use of
encryption and decryption in the document, using the rules
specified by the
with a key length of 256 bits.
The default value if this entry is omitted is 0, but a value of 1 or greater is
strongly recommended.
(See implementation note 23 in Appendix H.)
name
(Optional; meaningful only when the value of
ExtensionLevel
when decrypting streams. The name must be a key in the
or a standard crypt filter name specified in Table 3.23. All streams in the
document, except for cross-reference streams (see Section 3.4.7,
"Cross-Reference Streams") or streams that have a
Filter
using this crypt filter.
Default value: Identity.
,
, and
StmF
StrF
, and
entries
using algorithm 3.1 with a key length of 128
StrF
,
, and
CF
StmF
3) The name of the crypt filter that is used by default
array (see Table 3.5), are decrypted by the security handler,
Syntax (Chapter 3 in PDF Reference)
3.5 Encryption
V
) is to qualify them for use when
EFF
Old files may use this value but
entries using algorithm 3.1a
StrF
is
, or 5 for
V
4
Crypt
14
entry has a new
is
V
,
CF
dictionary
CF
entry in their
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