Skip to content

Latest commit

 

History

History
152 lines (85 loc) · 6.14 KB

README.md

File metadata and controls

152 lines (85 loc) · 6.14 KB
Raw

MultiNet Introduction

MultiNet is a lightweight model specially designed based on CRNN and CTC for the implementation of multi-command recognization with ESP32. Now, up to 100 speech commands, including customized commands, are supported.

Overview

MultiNet uses the MFCC features of an audio clip as input, and the phonemes (Chinese or English) as output. By comparing the output phonemes, the relevant Chinese or English command is identified.

Commands Recognition Process

  1. Add customized commands to the speech command queue.
  2. Prepare an audio clip of 30 ms (16 KHz, 6 bit, mono).
  3. Input this audio to the MFCC model and get its MFCC features.
  4. Input the obtained MFCC features to MultiNet and get the output phoneme.
  5. Input the obtained phoneme to the Language model and get the output.
  6. Compare the output against the existing speech commands one by one, and output the Command ID of the matching command (if any).

Please see the flow diagram below:

speech_command-recognition-system

User Guide

User-defined Command

Currently, users can define their own speech commands by using the command make menuconfig. You can refer to the method of adding speech commands in menuconfig->Component config > ESP Speech Recognition->Add speech commands, there are already 20 commands pre-stored in sdkconfig.

Command ID Command Command ID Command Command ID Command Command ID Command
0 打开空调 (Turn on the air conditioner) 5 降低一度 (Decrease by one degree) 10 关闭节能模式 (Disable power-saving mode) 15 播放歌曲 (Play a song)
1 关闭空调 (Turn on the air conditioner) 6 制热模式 (Heating mode) 11 除湿模式 (Dehumidifying mode) 16 暂停播放 (Pause playing)
2 增大风速 (Give me more wind) 7 制冷模式 (Cooling mode) 12 关闭除湿模式 (Disable dehumidifying mode) 17 定时一小时 (Set timer to 1 hour)
3 减少风速 (Give me less wind) 8 送风模式 (Ventilating mode) 13 打开蓝牙 (Enable the Bluetooth) 18 打开电灯 (Turn on the light)
4 升高一度 (Increase by one degree) 9 节能模式 (Power-saving mode) 10 关闭蓝牙 (Disable the Bluetooth) 19 关闭电灯 (Turn off the light)

MultiNet supports user-defined commands. You can add your own commands to MultiNet. Note that the newly added command should obtain its command ID before it can be recognized by MultiNet.

Add Speech Command

Users can define their own speech commands in the menuconfig in Pinyin, for example:

the command of “打开空调”, which means turn on the air conditioner, should be provided to the blank as "da kai kong tiao".

  • One speech commands ID can correspond to multiple speech command phrases;
  • Up to 100 speech commands ID or speech command phrases, including customized commands, are supported;
  • The corresponding multiple phrases for one Command ID need to be separated by ','.

Basic Configuration

Define the following two variables before using the command recognition model:

  1. Model version
    The model version has been configured in menuconfig to facilitate your development. Please configure in menuconfig and add the following line in your code:

    static const esp_mn_iface_t *multinet = &MULTINET_MODEL;

  2. Model parameter
    The language supported and the effectiveness of the model is determined by model parameters. Now only commands in Chinese are supported. Please configure the MULTINET_COEFF option in menuconfig and add the following line in your code to generate the model handle. The 6000 is the audio length for speech recognition, in ms, the range of sample_length is 0~6000.

    model_iface_data_t *model_data = multinet->create(&MULTINET_COEFF, 6000);

API Reference

Header

  • esp_mn_iface.h
  • esp_mn_models.h

Function

  • typedef model_iface_data_t* (*esp_mn_iface_op_create_t)(const model_coeff_getter_t *coeff, int sample_length);

    Definition

    Easy function type to initialize a model instance with a coefficient.

    Parameter

    • coeff: The coefficient for speech commands recognition.
    • sample_length: Audio length for speech recognition, in ms. The range of sample_length is 0~6000.

    Return

    Handle to the model data.

  • typedef int (*esp_mn_iface_op_get_samp_chunksize_t)(model_iface_data_t *model);

    Definition

    Callback function type to fetch the amount of samples that need to be passed to the detection function. Every speech recognition model processes a certain number of samples at the same time. This function can be used to query the amount. Note that the returned amount is in 16-bit samples, not in bytes.

    Parameter

    model: The model object to query.

    Return

    The amount of samples to feed the detection function.

  • typedef int (*esp_mn_iface_op_get_samp_chunknum_t)(model_iface_data_t *model);

    Definition

    Callback function type to fetch the number of frames recognized by the speech command.

    Parameter

    model: The model object to query.

    Return

    The number of the frames recognized by the speech command.

  • typedef int (*esp_mn_iface_op_get_samp_rate_t)(model_iface_data_t *model);

    Definition

    Get the sample rate of the samples to feed to the detection function.

    Parameter

    model: The model object to query.

    Return

    The sample rate, in Hz.

  • typedef float* (*esp_mn_iface_op_detect_t)(model_iface_data_t *model, int16_t *samples);

    Definition

    Easy function type to initialize a model instance with a coefficient.

    Parameter

    coeff: The coefficient for speech commands recognition.

    Return

    • The command id, if a matching command is found.
    • -1, if no matching command is found.

  • typedef void (*esp_mn_iface_op_destroy_t)(model_iface_data_t *model);

    Definition

    Destroy a voiceprint recognition model.

    Parameters

    model: Model object to destroy.