Repitch HQ Expansion (Sinc Interpolation)

[tucktuckg00se]

Prerequisite: #20 (Repitch Mode Upgrade — Linear/Cubic) must be stable and benchmarked first.

Added

• Sinc as an additional Repitch MODE option.
• Conditional POINTS parameter shown only when MODE = Sinc.

Planned POINTS Options

• 16
• 32
• 64
• Possibly 128 if CPU budget allows

Notes

• Sinc should not be added until the Linear/Cubic path is stable and benchmarked.
• Higher-quality sinc variants will need CPU testing against multi-voice playback, not just single voice listening tests.
• If Sinc is added, the UI should remain simple:
  • ALGO = Repitch
  • show MODE
  • only show POINTS when MODE = Sinc

Research Questions

• Whether MODE should remain fully slice-lockable once more interpolation types are added.
• Which point counts are worth exposing versus keeping internal.
• Whether Sinc should use a fixed quality level first before exposing multiple point options.