Description
Return octet = value+(negative ? 32 : 0).
CBOR combines a three-bit major type with additional information in an initial byte. Negative integers use an unsigned argument related by -1-n, while simple values and break markers have distinct meanings.
Return octet = value+(negative ? 32 : 0).
When to use this tool
Use CBOR Small Integer Initial Octet when checking one CBOR initial-byte, simple-value or negative-integer argument.
How to use the tool and how it works
- Enter value, negative. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read octet. Use the output convention below.
Require whole value in [0,23]. Return octet = value+(negative ? 32 : 0). With negative false the semantic integer is value; with negative true it is -1-value.1
CBOR type and argument conventions determine the encoded value. Constructing one argument or initial byte does not validate a full item.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| value | Unsigned CBOR argument 0-23; with negative true the represented integer is -1-value. | Required. Safe integer; minimum 0; maximum 23. |
| negative | Negative | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| octet | Octet | Required. Safe integer. |
{
"input": {
"value": 5,
"negative": false
},
"output": {
"octet": 5
}
}Limitations and assumptions
- value is CBOR's unsigned argument for the negative form, not the magnitude of the negative integer. This emits only the small-integer initial octet.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use a complete CBOR encoder or decoder to check type-specific validity, following arguments and complete item structure.
References
-
Calculation and input contract: encode/cbor-small-integer-initial-octet — tool.io
-
Concise Binary Object Representation: RFC 8949 — Internet Engineering Task Force
Similar or alternative tools
- CBOR Simple Value Initial Octet
Encode a CBOR simple-value code while rejecting reserved values 24 through 31.
- CBOR Negative Integer Initial Argument
Return CBOR’s exact unsigned argument for one supported negative integer.