Real-Time Implementation of Spatial Audio on FPGA Using Interaural Time Difference and Amplitude-Driven Perceptual Depth

This paper describes the real-time implementation of spatial audio effect using Basys-3 field programmable gate array (FPGA). The spatial audio effect in this paper is obtained by varying the azimuthal sound direction using interaural time difference (ITD) and amplitude-driven perceptual depth effect. In addition to the Basys-3 FPGA board, a peripheral module accessory (PMOD) I2S2 is used to take analog audio data from a mobile phone through an auxiliary-to-auxiliary cable and digitize it. This digitized data is then processed using a Verilog module and converted back to analog audio data using (PMOD) I2S2 to play the output audio through a pair of headphones. The introduction of varying azimuthal sound directions in the input data is carried out in real-time by introducing delays between the left and right audio channels of the data and a sense of perceptual depth is created by changing the amplitudes of the input data. A delay between the two channels is created by using a buffer. The amplitude of the input data is changed by scaling the input data. The delay between channels and the amplitude scaling varies dynamically with time. The effective deployment of techniques showcased in this paper promises FPGA-based approaches in audio processing for spatial audio. The findings offer important perspectives that can inform further enhancements of FPGA-based spatial audio rendering in audio processing.