From 143ccd69bde4b1269c55d5df9ab2773f88bc8963 Mon Sep 17 00:00:00 2001
From: Daisy <>
Date: Thu, 21 Dec 2023 17:41:06 +0800
Subject: [PATCH] =?UTF-8?q?=E6=96=B0=E5=A2=9Epcm=E8=BD=AC711=E6=96=B9?=
 =?UTF-8?q?=E6=B3=95?=
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---
 star_lock/lib/talk/call/g711Encode.dart | 33 +++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/star_lock/lib/talk/call/g711Encode.dart b/star_lock/lib/talk/call/g711Encode.dart
index 5369a366..3c004a3c 100644
--- a/star_lock/lib/talk/call/g711Encode.dart
+++ b/star_lock/lib/talk/call/g711Encode.dart
@@ -33,4 +33,37 @@ class G711Decoder {
 
     return Uint8List.fromList(g711Data);
   }
+
+  List<int> pcm16ToG711u(List<int> pcm16Data) {
+    List<int> g711uData = [];
+
+    for (int i = 0; i < pcm16Data.length; i += 2) {
+      int pcmSample = (pcm16Data[i + 1] << 8) | pcm16Data[i];
+      int g711Sample = pcmToG711u(pcmSample);
+
+      // 将 G.711 样本拆分成两个字节
+      g711uData.add(g711Sample & 0xFF);
+      g711uData.add((g711Sample >> 8) & 0xFF);
+    }
+
+    return g711uData;
+  }
+
+  int pcmToG711u(int pcmSample) {
+    const int MULAW_BIAS = 0x84;
+    const int CLIP = 32635;
+
+    // 剪裁 PCM 样本
+    if (pcmSample > CLIP) {
+      pcmSample = CLIP;
+    } else if (pcmSample < -CLIP) {
+      pcmSample = -CLIP;
+    }
+
+    // 增加偏置并取反
+    pcmSample += MULAW_BIAS;
+    pcmSample = ~pcmSample & 0xFF;
+
+    return pcmSample;
+  }
 }