:link_to_translation:`zh_CN:[中文]`
WakeNet is a wake word engine built upon neural network for low-power embedded MCUs. Currently, WakeNet supports up to 5 wake words.
Please see the flow diagram of WakeNet below:
- Speech Feature
- We use MFCC method to extract the speech spectrum features. The input audio file has a sample rate of 16KHz, mono, and is encoded as signed 16-bit. Each frame has a window width and step size of 30ms.
.. only:: latex
.. figure:: ../../_static/QR_MFCC.png
:alt: overview
- Neural Network
- Now, the neural network structure has been updated to the ninth edition, among which:
- WakeNet1, WakeNet2, WakeNet3, WakeNet4, WakeNet6, and WakeNet7 had been out of use.
- WakeNet5 only supports ESP32 chip.
- WakeNet8 and WakeNet9 only support ESP32-S3 chip, which are built upon the Dilated Convolution structure.
.. only:: latex
.. figure:: ../../_static/QR_Dilated_Convolution.png
:alt: overview
The network structure of WakeNet5, WakeNet5X2 and WakeNet5X3 is the same, but WakeNetX2 and WakeNetX3 have more parameters than WakeNet5. Please refer to :doc:`Resource Consumption <../benchmark/README>` for details.
- Keyword Triggering Method:
- For continuous audio stream, we calculate the average recognition results (M) for several frames and generate a smoothing prediction result, to improve the accuracy of keyword triggering. Only when the M value is larger than the set threshold, a triggering command is sent.
The wake words supported by Espressif chips are listed below:
| Chip | ESP32 | ESP32S3 | |||||
|---|---|---|---|---|---|---|---|
| model | WakeNet 5 | WakeNet 8 | WakeNet 9 | ||||
| WakeNet 5 | WakeNet 5X2 | WakeNet 5X3 | Q16 | Q8 | Q16 | Q8 | |
| Hi,Lexin | √ | √ | √ | √ | |||
| nihaoxiaozhi | √ | √ | √ | ||||
| nihaoxiaoxin | √ | ||||||
| xiaoaitongxue | √ | ||||||
| Alexa | √ | √ | |||||
| Hi,ESP | √ | ||||||
| Customized word | √ | ||||||
Select WakeNet model
To select WakeNet model, please refer to Section :doc:`Flashing Models <../flash_model/README>` .
To customize wake words, please refer to Section :doc:`Espressif Speech Wake-up Solution Customization Process <ESP_Wake_Words_Customization>`
Run WakeNet
WakeNet is currently included in the :doc:`AFE <../audio_front_end/README>`, which is enabled by default, and returns the detection results through the AFE fetch interface.
If users do not need WakeNet, please use:
afe_config.wakeNet_init = False.
If users want to enable/disable WakeNet temporarily, please use:
afe_handle->disable_wakenet(afe_data) afe_handle->enable_wakenet(afe_data)
For the resource occupancy for this model, see :doc:`Resource Occupancy <../benchmark/README>`.