Description
Expand channel-only MIDI running status into complete message records; incomplete data, system messages and realtime interleaving are rejected.
MIDI 1.0 channel messages use a status byte identifying a message type and a channel, followed by one or two seven-bit data bytes. This family uses channel indexes 0–15 and raw program values 0–127. Raw message bytes do not include musical timing, instrument state or a MIDI file container.1
Expand channel-only MIDI running status into complete message records; incomplete data, system messages and realtime interleaving are rejected.
When to use this tool
Use this tool to expand channel-only MIDI running status into complete message records; incomplete data, system messages and realtime interleaving are rejected.
How to use the tool and how it works
- Enter bytes using the field definitions below.
- Run the operation. Correct input errors before interpreting an output.
- Read result.messages. Use the ordering, boundary rules and absence conditions described below.
Read explicit channel status bytes and reuse the last status for following data-only groups. Validate each message’s required data length and return expanded records.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| bytes | Explicit integer byte values, each 0–255; data positions may require 0–127. | Dense list of at most 128 finite numbers; integer/shape constraints above also apply. |
| Output field | Interpretation |
|---|---|
| result | Object containing the named fields below. |
| result.messages | Explicit validated or transformed {status, data} records in source order. |
{
"input": {
"bytes": [
144,
60,
100,
62,
0
]
},
"output": {
"result": {
"messages": [
{
"status": 144,
"data": [
60,
100
]
},
{
"status": 144,
"data": [
62,
0
]
}
]
}
}
}Limitations and assumptions
- This supports channel messages only, without timing, system-common messages or interleaved real-time events.
- Message data bytes must be integers 0–127 and channel statuses 128–239. Channels are zero-based; this family does not implement MIDI 2.0 UMP, audio synthesis or a complete timed MIDI file.
- Every declared top-level input field is required and unexpected fields are rejected. Ordinary strings are limited to 8,192 UTF-16 code units and lists to 128 entries, with tighter operation-specific bounds where stated. JSON text has bounded nesting and node counts.
- Numeric outputs must be finite and no larger in absolute magnitude than the safe-integer limit; operations returning exact large integers use decimal text. Positions are zero-based and spans end exclusively unless the operation explicitly states a different convention.
Alternative or Complementary methods
Separate channel-message encoding from timing, running status and device interpretation. Use a MIDI sequencer or full file/stream parser when those additional layers matter.
References
-
Summary of MIDI 1.0 Messages — The MIDI Association
-
Tool behavior and example: MIDI Running Status Token Expander — tool.io
Similar or alternative tools
- MIDI Running Status Token Compactor
Compact consecutive equal explicit MIDI channel statuses into running-status byte tokens; no system or realtime record support.
- MIDI Status Byte Channel Join
Join MIDI 1.0 channel-message type 8–14 with zero-based channel 0–15; system message types are rejected.