ST H750支持SL（角度评估），属于声学应用领域，哪位比较懂？烦请指点一下，如下参数，什么意思：libSoundSourceLoc_Handler_Instance.channel_number = 4;  libSoundSourceLoc_Handler_Instance.M12_distance = DIAGONAL;
  libSoundSourceLoc_Handler_Instance.M34_distance = DIAGONAL;
  libSoundSourceLoc_Handler_Instance.sampling_frequency = AUDIO_IN_SAMPLING_FREQUENCY;  
  libSoundSourceLoc_Handler_Instance.algorithm = UserAudioStatus.SLocStatus.Algorithm;
  libSoundSourceLoc_Handler_Instance.ptr_M1_channels = 4;
  libSoundSourceLoc_Handler_Instance.ptr_M2_channels = 4;
  libSoundSourceLoc_Handler_Instance.ptr_M3_channels = 4;
  libSoundSourceLoc_Handler_Instance.ptr_M4_channels = 4;  
  libSoundSourceLoc_Handler_Instance.samples_to_process = 512;
  AcousticSL_getMemorySize( &libSoundSourceLoc_Handler_Instance);  

您从哪里拿到SL库的？一般在提供库文件的同时，会同步提供一个库文件的说明文档，类似下图中：