From 7920fa7726f6faf4fb783460750fa2756f9f31b6 Mon Sep 17 00:00:00 2001
From: Daniel Povey <dpovey@gmail.com>
Date: Mon, 12 Dec 2022 23:29:42 +0800
Subject: [PATCH] Add out_balancer for attention_squeeze, similar to
 nonlin_attention_module.

---
 .../ASR/pruned_transducer_stateless7/zipformer.py          | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/egs/librispeech/ASR/pruned_transducer_stateless7/zipformer.py b/egs/librispeech/ASR/pruned_transducer_stateless7/zipformer.py
index 65c2ffb0d..a122a112f 100644
--- a/egs/librispeech/ASR/pruned_transducer_stateless7/zipformer.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless7/zipformer.py
@@ -1403,6 +1403,13 @@ class AttentionSqueeze(nn.Module):
                                           prob=_aux_grad_prob_out(),
                                           bias=False, initial_scale=0.05)
 
+        self.out_balancer = ActivationBalancer(
+            channels, channel_dim=-1,
+            min_positive=0.4, max_positive=0.5,
+            min_abs=ScheduledFloat((0.0, 0.002), (8000.0, 0.02), (20000.0, 0.01)),
+        )
+
+
     def forward(self,
                 x: Tensor,
                 attn_weights: Tensor):