Turn more clear the VITS loss function

TTS/tts/layers/losses.py

@@ -586,6 +586,11 @@ class VitsGeneratorLoss(nn.Module):
         l = kl / torch.sum(z_mask)
         return l
 
+    @staticmethod
+    def cosine_similarity_loss(gt_spk_emb, syn_spk_emb):
+        l = - torch.nn.functional.cosine_similarity(gt_spk_emb, syn_spk_emb).mean()
+        return l
+
     def forward(
         self,
         waveform,
@@ -632,9 +637,7 @@ class VitsGeneratorLoss(nn.Module):
         loss = loss_kl + loss_feat + loss_mel + loss_gen + loss_duration
 
         if use_speaker_encoder_as_loss:
-            loss_se = (
-                -torch.nn.functional.cosine_similarity(gt_spk_emb, syn_spk_emb).mean() * self.spk_encoder_loss_alpha
-            )
+            loss_se = self.cosine_similarity_loss(gt_spk_emb, syn_spk_emb) * self.spk_encoder_loss_alpha
             loss += loss_se
             return_dict["loss_spk_encoder"] = loss_se