update

demo/ac_sound_capture1/ac_sound_capture1.cpp

@@ -153,7 +153,7 @@ void wavWriteVoice(string filename, uint32_t sample_rate, uint16_t bits_per_samp
 void sound_capture_callback(int32_t* voicedata, uint32_t len) {
   printf("sound_capture_callback:%d\n", len);
   for (size_t i = 0; i < len; i++) {
-    voicedata[i] = voicedata[i] - 420079616; //声望录音设备AC信号有一个直流偏移分量
+    voicedata[i] = voicedata[i] << 8; //底层采集的数据是24位，左移8位转换成32位
   }
 
   wavWriteVoice("record.wav", 96000, 32, 1, (char*)voicedata, len * sizeof(int32_t));