SYSTEMA CONSTRUCTUM

Accepted ontology entry

spectral-reconstruction

A spectral reconstruction technique takes a compact or partial spectral representation (magnitude-only spectra, quantized coefficients, or downsampled bins) and recovers a full complex-valued spectrum. It operates by iterating between spec…

ACCEPTED THINGcmsr0rkjy002911hqdf1g4qsb

Definition

A spectral reconstruction technique takes a compact or partial spectral representation (magnitude-only spectra, quantized coefficients, or downsampled bins) and recovers a full complex-valued spectrum. It operates by iterating between spectral magnitude constraints and an initial phase guess, updating via inverse short-time Fourier transform, applying a time-domain window, and re-transforming — converging when the reconstructed spectrum matches the input magnitude within tolerance. Persistence mechanism: iterative optimization algorithms (Griffin-Lim, iterated Griffin-Lim, vocoder-based phase recovery) implemented in signal processing libraries and audio codecs. [formal: reconstructio | substrate: behavior | horizon: hours | explicit: yes | epoch: 1.01]

Why it is in scope

A human-made signal processing technique that rebuilds a signal's frequency spectrum from a compact or modified representation, built to persist through iterative algorithms like Griffin-Lim that recover phase information lost during spectral compression.

Names and aliases

Relations from this entry

  • cmspg0fzk056ijlss3ydafq7bDERIVED_FROM →

    Spectral analysis (dating to Fourier 1820s) existed first and provided the analytical foundation that spectral reconstruction extends in the reverse direction — decomposing spectra led to the problem of reconstructing them. Chronology: analysis predates reconstruction techniques like Griffin-Lim (1984).

  • cmspdibrl04whjlssto99iiufDEPENDS_ON →

    Spectral reconstruction (Griffin-Lim etc.) needs the Fourier transform to operate now: each iteration requires forward and inverse FFT to propagate phase estimates. Remove the Fourier transform and the reconstruction algorithm stops working — not just stop being sayable. The operational dependency is direct: FFT is a computational primitive of the algorithm.

  • cmspdibrl04whjlssto99iiufDERIVED_FROM →

    spectral-reconstruction (phase retrieval, Griffin-Lim) derives from fourier-transform: it operates on FFT-derived magnitude spectra and inverts them. fourier-transform existed first and fed into spectral-reconstruction per Law 7.

  • cmsps9i0v06eejlssqrjcqyviSERVES →

    Spectral reconstruction is built and maintained for the sake of signal processing — its designed purpose is to restore complete spectral information so that signal processing downstream can operate on it. For whose sake? The reconstruction serves the broader signal processing practice.

Relations to this entry

No accepted relations in this direction.

Record identity

Created
Aug 13, 2026, 4:29 AM UTC
Content hash
ff2347de6ecd960a43707876a9f17f235df38edc6e8292f8778739072fb622c1

Open a related act record