Automatic Latency Estimation for Vocal Capture Sync
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The variability in latency across different handheld device platforms, such as Android and iOS devices, poses a challenge for synchronizing vocal performances with backing tracks in karaoke and vocal capture applications, as fixed latency estimates are inadequate and require frequent updates.
Innovation Solution
A method using feedback recording and analysis to estimate round-trip latency through audio subsystems of portable computing devices, which involves playing a known audio signal, capturing it, and analyzing the recorded audio to determine correlated peaks, allowing for adaptive timing and synchronization adjustments in vocal performance capture applications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If fixed latency estimates are used in audio subsystems, then synchronization is simplified, but synchronization accuracy deteriorates due to platform variability
Solution Approach 1:
The patent implements dynamic latency estimation by automatically measuring round-trip latency through feedback recording at runtime rather than using fixed predetermined values. The system continuously adapts latency compensation based on actual measured values from each device platform, transforming the static latency compensation approach into a dynamic one that adjusts to platform-specific characteristics.
Solution Approach 2:
The patent employs feedback recording where the audio output is captured back through the microphone to measure the actual round-trip latency. This feedback loop allows the system to automatically determine the precise latency introduced by the audio subsystem and compensate accordingly, resolving the contradiction between simplicity and accuracy by using automated measurement rather than manual configuration.
2Measurement precision
If platform-specific latency updates are implemented, then synchronization accuracy improves, but development cost and complexity increase
Solution Approach 1:
The patent enables the audio subsystem to self-measure and self-compensate for latency issues automatically. The system performs its own latency measurement through feedback recording and applies compensation without requiring external intervention or manual configuration for each platform, thereby improving synchronization accuracy while avoiding the complexity of manual platform-specific updates.
Solution Approach 2:
The patent dynamically changes the latency compensation parameter based on measured values from each platform. Instead of hardcoding different latency values for each platform, the system measures the actual latency and adjusts the compensation parameter automatically, simplifying development while maintaining high synchronization accuracy across diverse platforms.
3Measurement precision
If manual latency estimation updates are performed frequently, then synchronization accuracy improves, but time and resource consumption increase
Solution Approach 1:
The patent performs latency measurement and compensation setup automatically during the initial application launch or first use, rather than requiring frequent manual updates. This preliminary automated action establishes the correct latency compensation for each device, eliminating the need for time-consuming manual updates while maintaining accurate synchronization.
Solution Approach 2:
The patent replaces the manual mechanical process of updating latency estimates with an automated electronic measurement and adjustment system. The feedback recording and automatic parameter adjustment eliminate the need for human intervention and repeated updates, saving time and resources while maintaining precision.
Data Source
AI summary
Latency on different devices (e.g., devices of differing brand, model, vintage, etc.) can vary significantly and tens of milliseconds can affect human perception of lagging and leading components of a performance. As a result, use of a uniform latency estimate across a wide variety of devices is unlikely to provide good results, and hand-estimating round-trip latency across a wide variety of devices is costly and would constantly need to be updated for new devices. Instead, a system has been developed for automatically estimating latency through audio subsystems using feedback recording and analysis of recorded audio.