KDM Validity Window Calculator
Declared half-openKDMnotBefore≤t<notAftertimeauditONLY, not signature/decryption/certchain/playback authorization; not inclusiveX509validity semantics. Time zone/interval convention independently verified.
Description
A recorded KDM time window can be audited under an explicit start-inclusive and end-exclusive convention.
A recorded KDM time window can be audited under an explicit start-inclusive and end-exclusive convention.1
This tool compares epoch times without validating signatures, certificates, decryption or playback authorization.
When to use KDM Validity Window Calculator
This tool compares epoch times without validating signatures, certificates, decryption or playback authorization.
How to use KDM Validity Window Calculator and how it works
- Prepare actualKdmNotBeforeEpochMs, actualKdmNotAfterEpochMs, actualObservedPlaybackEpochMs, with the units, conventions and assumptions below.
- Enter the required fields and run KDM Validity Window Calculator.
- Read result.withinDeclaredHalfOpenKdmInterval, result.signedMillisecondsUntilEnd using the output definitions below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualKdmNotBeforeEpochMs | Actual Kdm Not Before Epoch Ms. Use the units and matching context stated in the calculation below. | number | Required; finite; other constraints below |
| actualKdmNotAfterEpochMs | Actual Kdm Not After Epoch Ms. Use the units and matching context stated in the calculation below. | number | Required; finite; other constraints below |
| actualObservedPlaybackEpochMs | Actual Observed Playback Epoch Ms. Use the units and matching context stated in the calculation below. | number | Required; finite; other constraints below |
Supply finite numeric start, end and query timestamps in milliseconds on the same time basis, with end strictly greater than start. Return whether start<=query<end and the signed end-minus-query margin. The end is exclusive; a time before the start can have a positive end margin while validity is false. No KDM parsing, signature validation or cinema-server authorization occurs.
valid=(start<=query && query<end); remainingMilliseconds=end-query Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.withinDeclaredHalfOpenKdmInterval | True when query is at or after start and strictly before end. | boolean |
| result.signedMillisecondsUntilEnd | End minus query in milliseconds; negative after end. | number |
{
"input": {
"actualKdmNotBeforeEpochMs": 0,
"actualKdmNotAfterEpochMs": 2000,
"actualObservedPlaybackEpochMs": 1000
},
"output": {
"result": {
"withinDeclaredHalfOpenKdmInterval": true,
"signedMillisecondsUntilEnd": 1000
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Theatrical Window Days Calculator for a complementary operation: A theatrical window can be recorded as elapsed calendar days between two distribution dates.
Use Changeover Cue Mark Calculator for a complementary operation: A changeover cue index can be recorded from reel length and an independently established lead in frames.
References
-
KDM Validity Window Calculator — tool.io
Similar or alternative tools
- Theatrical Window Days Calculator
A theatrical window can be recorded as elapsed calendar days between two distribution dates.
- Changeover Cue Mark Calculator
A changeover cue index can be recorded from reel length and an independently established lead in frames.