Note Event Time Reversal
Reverse note intervals within an explicit tick window, preserving durations and caller order; all events must fit.
Description
Reverse note intervals within an explicit tick window, preserving durations and caller order; all events must fit.
Reversing note time reflects each entire event interval inside a declared window rather than merely negating its start.
When to use this tool
Reverse note intervals within an explicit tick window, preserving durations and caller order; all events must fit.
- Prepare the supplied eventsJson, window fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter eventsJson, window. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.events. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
Require every start plus duration no greater than nonnegative integer window. Set each new start to window minus start minus duration, preserving duration, pitch, channel and record order.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| eventsJson | JSON text, entered as one text field. The decoded structure is illustrated below; it is not a separate file. | Text |
| window | window. | Integer from 0 to 1e9 inclusive |
For the JSON text fields, the following decoded structures show the example records before they are serialized into input strings. Keep field names, list nesting and value types as shown.
[
{
"field": "eventsJson",
"decoded": [
{
"start": 1,
"duration": 3,
"pitch": 60,
"channel": 0
}
]
}
]| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.events | The events list in the ordering and representation described above. |
{
"input": {
"eventsJson": "[{\"start\":1,\"duration\":3,\"pitch\":60,\"channel\":0}]",
"window": 10
},
"output": {
"result": {
"events": [
{
"start": 6,
"duration": 3,
"pitch": 60,
"channel": 0
}
]
}
}
}Limitations and assumptions
- The returned list is not sorted by its new starts. No audio reversal or note-on/off stream conversion occurs.
- Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
- Lists are limited to 128 entries. JSON text must meet bounded size and depth checks, and numeric outputs beyond the safe finite magnitude are rejected. Exact large integers use decimal strings.
- Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.
Alternative or Complementary methods
Retain the tick unit, channel numbering and event-pairing policy with the result. Use a MIDI-file parser or audio analysis when the task requires actual messages, playback behavior or recorded sound.
References
Similar or alternative tools
- delay time synced to note value
Tempo-synced delay time in milliseconds for a note expressed in quarter-note multiples.
- Note Event Channel Partition
Partition explicit note events by channel in first-appearance order while retaining event order and numerical evidence.