NanoEdge AI Library for extrapolation (E)

Revision as of 15:38, 22 November 2021 by Registered User

1. What is NanoEdge AI Library for extrapolation?

NanoEdge™ AI Library is an Artificial Intelligence (AI) static library originally developed by Cartesiam, for embedded C software running on Arm® Cortex® microcontrollers.

When embedded on microcontrollers, it gives them the ability to easily "predict" target value from sensor patterns, by themselves, without the need for the user to have additional skills in Mathematics, Machine Learning, or data science.

The NanoEdge AI static library for extrapolation is the code that contains an AI model (for example, as a bundle of signal treatment, Machine Learning model, and optimally tuned hyperparameters) designed to estimate / predict a target value from a sensor pattern. The predicted values (target values) used to fit the model are defined by the user in NanoEdge AI Studio (NanoEdgeAIStudio), also called the Studio) and are used during the training process of the AI model.

Info white.png Information
The library is not available in the free version of the Studio.

2. Install / Getting started

The main functions available via the library are:

init() run first before the extrapolation process to load the knowledge
extrapolation() run a regression process for extrapolation, to predict the response (inference)
status() returns the current status of the library

2.1. Static library

The static NanoEdge AI Library is only available via NanoEdge AI Studio in its full version.

  • In NanoEdge AI Studio, after obtaining a library, click Compile (on the "Deploy" screen, which follows the "Optimize and Benchmark" and "Emulator" screens)
  • Open the .zip file obtained
  • Select and copy the static library libneai.a
  • Link this static library to your project code

2.2. NanoEdge AI Library functions

2.2.1. Initialization

enum neai_state neai_extrapolation_init(const float knowledge_buffer[]);

Initialization must be called at the beginning to load the knowledge.

  • Input:
const float knowledge_buffer[], this buffer is defined in the header file knowledge.h provided in the .zip file containing the static NanoEdge AI Library.
  • Output:
0 means success (the knowledge has been loaded), other values mean that loading has failed.
123: the library is being used on a board that is not authorized (only for libraries that are limited to partner/authorized development boards).

For more details on the output of the initialization function, refer to the header file NanoEdgeAI.h provided in the .zip file containing the static NanoEdge AI Library.

2.2.2. Extrapolation

float neai_extrapolation(float input_buffer[]);

This function returns the target extrapolated value.

  • Input:
float input_buffer[], the length of the buffer is DATA_INPUT_USER * AXIS_NUMBER.
  • Output:
The predicted value (floating point).
Warning white.png Warning
NanoEdge AI Library uses float data types instead of int. If you are using intdata types, convert (cast) them into float.

2.2.3. Getting status

enum neai_state neai_extrapolation_status(void);

This function returns the current status of the library.

  • Input: None
  • Output: The status of the library. For more details refer to the header file NanoEdgeAI.h provided in the .zip file containing the static NanoEdge AI Library.

2.3. Example "Hello World!"

Header files:

NanoEdgeAI.h and knowledge.h (provided in the .zip file that you download by clicking Compile in NanoEdge AI Studio (on the "Deploy" screen after obtaining a library)

Example of NanoEdge AI Library header file:

This snippet is provided AS IS, and by taking it, you agree to be bound to the license terms that can be found here for the component: Application.
                                                                                             
/* =============
Copyright (c) 2020, STMicroelectronics

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that
the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the
  following disclaimer.

* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
  following disclaimer in the documentation and/or other materials provided with the distribution.

* Neither the name of the copyright holders nor the names of its contributors may be used to endorse or promote
  products derived from this software without specific prior written permission.

*THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER / OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.*
*/

#ifndef __NANOEDGEAI_H__
#define __NANOEDGEAI_H__

/* Includes */
#include <stdint.h>

/* Define */

#define DATA_INPUT_USER 13
#define AXIS_NUMBER 1

enum neai_state { 
    OK = 0,
    INIT_FCT_NOT_CALLED = 123,
    BOARD_ERROR,
    KNOWLEDGE_BUFFER_ERROR,
    NOT_ENOUGH_CALL_TO_LEARNING_FCT, //This is a fail-safe to prevent users from learning one or even no signals.
    UNKNOWN_ERROR};

/* Input buffer */
float input_user_buffer[DATA_INPUT_USER  * AXIS_NUMBER];

/* Function prototypes */
#ifdef __cplusplus
extern "C" {
#endif
	enum neai_state neai_extrapolation_init(const float knowledge_buffer[]);
	float neai_extrapolation(float input_buffer[]);
	enum neai_state neai_extrapolation_status(void);
#ifdef __cplusplus
}
#endif

#endif
Warning DB.png Important
  • The input buffer collected from your sensor is already declared in the header file NanoEdgeAI.h, float input_user_buffer[DATA_INPUT_USER * AXIS_NUMBER];, feel free to comment this line, and then rename and declare your input buffer in the main program.
  • The knowledge buffer knowledge is declared in the header file knowledge.h.


Main program: main.c

This program must be completed by the user (depending on the applications or the desired features).

This snippet is provided AS IS, and by taking it, you agree to be bound to the license terms that can be found here for the component: Application.
/* =============
Copyright (c) 2020, STMicroelectronics

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that
the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the
  following disclaimer.

* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
  following disclaimer in the documentation and/or other materials provided with the distribution.

* Neither the name of the copyright holders nor the names of its contributors may be used to endorse or promote
  products derived from this software without specific prior written permission.

*THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER / OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.*
*/
/* Includes --------------------------------------------------------------------*/
#include "NanoEdgeAI.h"
#include "knowledge.h"
/* Private define --------------------------------------------------------------*/
/* Private variables defined by user -------------------------------------------*/
/* Private function prototype defined by user ----------------------------------*/
/*
 * @brief Collect data process
 *
 * This function is defined by user, depends on applications and sensors
 *
 * @param sample_buffer: [in, out] buffer of sample values
 *
 * @retval None
 */
void get_buffer(float sample_buffer[])
{
	/* USER BEGIN */
	/* USER END */
}
/* -----------------------------------------------------------------------------*/
int main()
{
	/* Initialization -----------------------------------------------------------*/
	enum NanoEdgeAI_state error_code = neai_extrapolation_init(knowledge);
	if (error_code != OK) {
		/* This happen if the knowledge do not correspond to the library or if the library work into a not supported board. */
	}
	/* Extrapolation -----------------------------------------------------------*/
	uint8_t extrapolation_value;
	while (true) {
		get_buffer(input_user_buffer);
		extrapolation_value = neai_extrapolation(input_user_buffer);
		/* USER BEGIN */

		/* USER END */
	}
}

3. Resources

Documentation
All NanoEdge AI Studio documentation is available here.

Tutorials
Step-by-step tutorials, to use NanoEdge AI Studio to build a smart device from A to Z.