Complete Communications Engineering

The decryption template conveys to the decryptor how to decrypt received codestream. There are 3 types of ciphers specified in the JPSEC standard:

  • Block-cipher
  • Stream-cipher
  • Asymmetric-cipher

Table 1 shows the list of block-ciphers that are specified in the standard. The only stream-cipher specified is SNOW2 and the only asymmetric-cipher is RSA-OAEP.

Table 1: JPSEC Block-cipher Identifiers

IdentifierCipher Type
0x0000NULL (no encryption)
0x0001AES
0x0002TDEA
0x0003MISTY-1
0x0004Camellia
0x0005CAST-128
0x0006SEED
All other values are reserved for ISO use

The block-cipher template also defines a mode of operation and a padding mode. Table 2 shows the JPSEC defined modes of operation and table 3 shows the defines the padding modes.

Table 2: JPSEC Block-cipher Modes of Operation

IdentifierMode of Operation
0Reserved
x0 xxxxBits are not padded
x1 xxxxBits are padded
0x 0001ECB (mode without IV)
1x 0010CBC (mode with IV)
1x 0011CFB (mode with IV)
1x 0100OFB (mode with IV)
1x 0101CTR (mode with IV)
All other values are reserved for ISO use

Table 3: JPSEC Block-cipher Padding Modes

ValuePadding Mode
00Ciphertext Stealng
01PKCS#7-padding
All other values are reserved for ISO use

All three ciphers have the key template as a cipher parameter. The block-cipher also specifies the cipher
mode, padding mode and size of block in bytes.

Further information available here:

JPSEC

JPSEC Tools

JPSEC Tool Authentication Template

JPSEC Tool Hash Template

JPSEC Tool Key Template

JPSEC Registration Authority (RA)
JPSEC Standards available here:

Joint Photographic Experts Group (JPEG) Part 8 – JPSEC: Secure JPEG 2000 Final Committee Draft

ISO/IEC 15444-8:2007 – Information technology — JPEG 2000 image coding system: Secure JPEG 2000

T.807 (05/06) – Information technology — JPEG 2000 image coding system: Secure JPEG 2000