From 2574ce5ea26e11be1b9b3931e1d5d5067d1c33d2 Mon Sep 17 00:00:00 2001
From: Alex Murkoff <79400603+alexlnkp@users.noreply.github.com>
Date: Tue, 11 Jun 2024 16:23:13 +0700
Subject: [PATCH] feat(audio): pre-allocate decoded_audio array in the
 load_audio function

this should improve performance, even if just a little
---
 infer/lib/audio.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/infer/lib/audio.py b/infer/lib/audio.py
index 61acc5b..43733af 100644
--- a/infer/lib/audio.py
+++ b/infer/lib/audio.py
@@ -42,7 +42,9 @@ def load_audio(file: str, sr: int) -> np.ndarray:
     try:
         container = av.open(file)
         resampler = AudioResampler(format='fltp', layout='mono', rate=sr)
-        decoded_audio = []
+
+        # AV stores duration in nanoseconds
+        decoded_audio = (((container.duration * sr / container.bit_rate) // 1_000_000) + 1)*[]
 
         for frame in container.decode(audio=0):
             frame.pts = None  # Clear presentation timestamp to avoid resampling issues