MIDI Playback Timing Reset for Jitter and Latency Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic musical instruments face issues with listener discomfort due to fluctuations in tone generation timing caused by jitter and latency in MIDI message reception, and excessive latency when fixed offset times are used.
Innovation Solution
An electronic apparatus and method that adjusts the scheduled output timing of MIDI messages based on received timestamps, resetting the reference timing and timestamp when the scheduled output time is before the reception time to maintain appropriate time differences between tone generations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fixed offset time is provided from reception until tone generation of a MIDI message, then it is possible to generate the tone while maintaining the time difference with the MIDI message of which the tone is generated earlier, but excessive latency that originally could have been avoided may occur
Solution Approach 1:
The offset time is changed from a fixed value to a dynamically adjustable value based on the reception timing of MIDI messages. When a MIDI message is received later than its scheduled output time, the offset time for subsequent messages is reduced or set to zero, allowing the system to adapt to actual reception conditions and avoid excessive latency while maintaining temporal relationships between messages.
Solution Approach 2:
The offset time parameter is modified based on the reception timing of MIDI messages. The system monitors whether messages are received before or after their scheduled output times and adjusts the offset time parameter accordingly, changing it from a static fixed value to a dynamic value that optimizes both latency and time difference maintenance.
2Reliability
If the tone of a subsequent MIDI message is generated at the scheduled output time calculated from the reference time, then the time difference between tone generations can be maintained, but if the MIDI message is received earlier than the scheduled output time, the tone generation timing may feel too early to the listener
Solution Approach 1:
The system monitors the reception timing of MIDI messages and uses this feedback to adjust the offset time for subsequent messages. When messages are received later than expected, the offset time is reduced to prevent early tone generation that would cause listener discomfort, while still maintaining the temporal relationships between messages.
Solution Approach 2:
The offset time is made dynamic and adjustable based on actual reception conditions. The system adapts the offset time in real-time based on whether messages are received early or late, allowing flexible adjustment to prevent listener discomfort while maintaining time difference integrity.
Data Source
Figure 1(a)~1(c)
Figure 2
Figure 3(a)~3(b)
AI summary
In the present invention, when a MIDI message is received later than a scheduled output time, the MIDI message is immediately played, and the reception timing of the MIDI message and a time-stamp thereof are reset to a reference time and a reference time-stamp. As a result, because a time difference in terms of playing timing between the subsequent MIDI message and the MIDI message associated with the reference time and the reference time-stamp can be determined based on a time difference between the time-stamps of these MIDI messages, a listener's sense of unnaturalness due to the playing timing of the subsequent MIDI message can be suppressed. In addition, an initial MIDI message is output instantly after the reception thereof such that a time lag between the start of transmission of the MIDI message at a portable terminal 50 and the start of playing at a synthesizer 1 can be suppressed. As a result, the occurrence of a latency between MIDI messages can be suppressed.