From 748219e64cf20e8e9344fb6aea49f431f0119b4e Mon Sep 17 00:00:00 2001
From: roebel <roebela@free.fr>
Date: Wed, 21 Jun 2023 12:21:11 +0200
Subject: [PATCH] Fix inefficient phase unwrapping (#7)

---
 vocos/heads.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/vocos/heads.py b/vocos/heads.py
index 181865f..21863f1 100644
--- a/vocos/heads.py
+++ b/vocos/heads.py
@@ -54,10 +54,15 @@ def forward(self, x: torch.Tensor) -> torch.Tensor:
         mag, p = x.chunk(2, dim=1)
         mag = torch.exp(mag)
         mag = torch.clip(mag, max=1e2)  # safeguard to prevent excessively large magnitudes
+        # wrapping happens here. These two lines produce real and imaginary value
         x = torch.cos(p)
         y = torch.sin(p)
-        phase = torch.atan2(y, x)
-        S = mag * torch.exp(phase * 1j)
+        # recalculating phase here does not produce anything new
+        # only costs time
+        # phase = torch.atan2(y, x)
+        # S = mag * torch.exp(phase * 1j)
+        # better directly produce the complex value 
+        S = mag * (x + 1j * y)
         audio = self.istft(S)
         return audio