Purpose

Spectrum Publish takes stereo audio and emits a spectrum ring. It is a lightweight way to expose the current frequency content of a signal for analysis and spectrum-aware downstream nodes, computing one windowed FFT frame from each engine block.

TouchDesigner Use

Wire stereo audio into in and route out to any node that reads a spectrum ring. Reach for this when you want frequency content published from a point in the chain without managing overlapped framing. For a transparent analyze-and-resynthesize round trip back to audio, use Spectrum STFT into Spectrum ISTFT instead.

Inputs And Outputs

• Input 0: in accepts stereo PCM. It is required.
• Output 0: out emits a stereo spectrum ring.

Main Controls

• Windowsize: FFT window in samples: 512, 1024, 2048, or 4096. Larger windows give finer frequency detail.
• Hopsize: window advance as a fraction of the window: quarter, half, full, or eighth.
• Window: window shape: hann, blackman, or rect.

Notes

• Input must be stereo.
• A block shorter than the selected window is zero-padded for the frame.
• For full spectral processing and resynthesis, pair Spectrum STFT with Spectrum ISTFT rather than using this publisher.

Parameters

This operator does not expose user parameters in the extracted schema.

Catalog metadata

Roles

• transform

Tags

None listed.

Search groups

• audio
• spectrum