Colour Enhanced Time/Pressure Envelope (CETPE), a novel on-screen rendering of digital sound

Journal title RIVISTA ITALIANA DI ACUSTICA
Author/s Cesare Brizio
Publishing Year 2024 Issue 2023/2
Language Italian Pages 8 P. 55-62 File size 0 KB
DOI 10.3280/ria2-2023oa16390
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The most widespread forms of digital sound rendering in audio-management software applications include Time/Pressure Envelopes (TPÈs aka “oscillograms”), Frequency/Pressure Analyses (FPA’s), and Time/Frequency Spectrographic Images (TFSI, often referred to as “spectrograms”). Only the latter, thanks to the colour mapping of pressure values, are capable to deliver simultaneously visual information about the three numerical domains (time, horizontal axis; frequency, vertical axis; pressure, colour) digitally defining the acoustic phenomenon.Here the Colour Enhanced Time/Pressure Envelope (CETPE) is proposed, a 24-bit RGB colour mapped form of the commonplace TPE available on-screen in any digital audio software: this novel Fast Fourier Transform (FFT)-based rendering, controlled by userdefined parameters, is capable to deliver partial but potentially relevant information about the presence and the intensity of interesting frequency bands in an audio file.A proof-of-concept demonstrator of the 2-color CETPE was developed in Python language, and a sample output screen, consistent with the expected look of the rendering, is included in this paper.

Keywords: ; FFT; Oscillogram; Spectrogram; Screen; Colour; Digital

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Cesare Brizio, Colour Enhanced Time/Pressure Envelope (CETPE), una nuova rappresentazione del suono digitale su schermo in "RIVISTA ITALIANA DI ACUSTICA" 2/2023, pp 55-62, DOI: 10.3280/ria2-2023oa16390