where T_b is the band‑specific threshold and α_b controls the knee curvature. The RMS detector uses a 50 ms smoothing window. The final output for band b is
with β controlling drive (0 ≤ β ≤ 5) and γ the blend factor (0 ≤ γ ≤ 1). The high‑shelf has a cutoff at 4 kHz and a gain of up to +6 dB. Let L[n] and R[n] denote left/right channels. The Mid (M) and Side (S) components are
[ y_b[n] = G_b[n] \cdot x_b[n]. ]
[ G_\mathrmLU = 10^(L_\mathrmtarget - L_\mathrmint)/20. ]
DFX Audio Enhancer Full: Architecture, Signal‑Processing Techniques, and Perceptual Evaluation dfx audio enhancer full
Cross‑fading between adjacent bands uses a cosine‑squared window to avoid discontinuities. The exciter applies a non‑linear function f(·) followed by a high‑shelf filter H_s(·) :
| Module | CPU % (single‑thread) | Memory (MB) | Real‑time factor | |--------|----------------------|-------------|-------------------| | Pre‑EQ | 2.1 | 1.8 | 0.97 | | Multiband Compressor | 4.5 | 2.3 | 0.94 | | Harmonic Exciter | 3.2 | 1.5 | 0.96 | | Stereo Widening | 2.8 | 2.0 | 0.97 | | Loudness Maximizer | 2.0 | where T_b is the band‑specific threshold and α_b
[ L'[n] = M[n] + S'[n],\qquad R'[n] = M[n] - S'[n]. ] A perceptual loudness model based on the ITU‑R BS.1770‑4 algorithm computes the integrated loudness L_int over a 400 ms window. The target loudness L_target (default = –14 LUFS) determines a gain factor
[Your Name], [Affiliation] – Department of Electrical Engineering & Computer Science [Co‑author Name], [Affiliation] – Institute for Audio Research The high‑shelf has a cutoff at 4 kHz
[ M[n] = \fracL[n] + R[n]2,\qquad S[n] = \fracL[n] - R[n]2. ]
