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ISCC - Types and Constants#

MT #

MT - MainTypes#
Uint Symbol Bits Purpose
0 META 0000 Match on metadata similarity
1 SEMANTIC 0001 Match on semantic content similarity
2 CONTENT 0010 Match on perceptual content similarity
3 DATA 0011 Match on data similarity
4 INSTANCE 0100 Match on data identity
5 ISCC 0101 Composite of two or more ISCC-UNITs with common header

ST #

ST - SubTypes#
Uint Symbol Bits Purpose
0 NONE 0000 For MainTypes that do not specify SubTypes

ST_CC #

ST_CC#

SubTypes for MT.CONTENT

Uint Symbol Bits Purpose
0 TEXT 0000 Match on syntactic text similarity
1 IMAGE 0001 Match on perceptual image similarity
2 AUDIO 0010 Match on audio chroma similarity
3 VIDEO 0011 Match on perceptual similarity
4 MIXED 0100 Match on similarity of content codes

ST_ISCC #

ST_ISCC#

SubTypes for MT.ISCC

Uint Symbol Bits Purpose
0 TEXT 0000 Composite ISCC inlcuding Text-Code
1 IMAGE 0001 Composite ISCC inlcuding Image-Code
2 AUDIO 0010 Composite ISCC inlcuding Audio-Code
3 VIDEO 0011 Composite ISCC inlcuding Video-Code
4 MIXED 0100 Composite ISCC inlcuding Mixed-Code
5 SUM 0101 Composite ISCC inlcuding only Data- and Instance-Code
6 NONE 0110 Composite ISCC including Meta, Data and Instance-Code
7 WIDE 0111 Composite ISCC with 128-bit Data- and Instance-Code

VS #

VS - Version#

Code Version

Uint Symbol Bits Purpose
0 V0 0000 Initial Version of Code or Unit
1 V1 0001 Updated Version of Code or Unit

LN #

LN - Length#

Valid lengths for hash-digests.

  • L32 = 32
  • L64 = 64
  • L72 = 72
  • L80 = 80
  • L96 = 96
  • L128 = 128
  • L160 = 160
  • L192 = 192
  • L224 = 224
  • L256 = 256

MULTIBASE #

Supported Multibase encodings.

  • base16 -> f
  • base32 -> b
  • base32hex -> v
  • base58btc -> z
  • base64url -> u