SGS WNR ALGORITHM USER GUIDE¶

REVISION HISTORY¶

Revision No.	Description	Date
1.0	Initial release	07/19/2024
1.01	Update file description and copyright	04/25/2025
1.02	Remove copyright	05/14/2025
1.03	Update description	05/21/2025
1.1	Remove wnr_mode 0 and related API	11/03/2025

1. Overview¶

1.1. Algorithm Description¶

Wind Noise Reduction algorithm (WNR) is designed to suppress wind noise in the environment to improve speech quality. If the Library file contains deep learning mode (MODE1), dynamic library is not supported.

2. API Reference¶

API Name	Function
IaaWnr_GetBufferSize	Get the memory size required to run the WNR algorithm
IaaWnr_Init	Initialize WNR algorithm
IaaWnr_Config	Set WNR algorithm parameters
IaaWnr_Run	Run WNR algorithm
IaaWnr_Free	Free WNR algorithm resources
IaaWnr_SetHandleId	Set WNR algorithm ID
IaaWnr_GetJsonFileSize	WNR get size of json file
IaaWnr_InitReadFromJson	Set json parameter into WNR init structure
IaaWnr_ConfigReadFromJson	Set json parameter into WNR config structure

2.1. IaaWnr_GetBufferSize¶

Function

Get the memory size required to run the WNR algorithm

Syntax

unsigned int IaaWnr_GetBufferSize(void);

Parameter

Parameter Name Description Input/Output

N/A
Return Value

The return value is the memory size required to run the WNR algorithm.
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

This interface only returns the required memory size. To apply and release the memory, you need to use other APIs.
Example

Please refer to the example section of IaaWnr_Run.

2.2. IaaWnr_Init¶

Function

Initialize WNR algorithm

Syntax

WNR_HANDLE IaaWnr_Init(char* const working_buffer_address, AudioWnrInit *wnr_init);

Parameter

Parameter name Description Input/Output

working_buffer_address Memory address used by WNR algorithm Input

wnr_init WNR algorithm initialization structure pointer Input
Return Value

Return Value Result

Non-NULL Successful

NULL Failed
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A
Example

Please refer to IaaWnr_Run example.

2.3. IaaWnr_Config¶

Function

Set WNR algorithm parameters.

Syntax

ALGO_WNR_RET IaaWnr_Config(WNR_HANDLE handle, AudioWnrConfig *wnr_config);

Parameter

Parameter name Description Input/Output

handle WNR algorithm handle Input

wnr_config WNR algorithm parameter setting structure Input
Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A
Example

Please refer to IaaWnr_Run example

2.4. IaaWnr_Run¶

Function

Run WNR algorithm.

Syntax

ALGO_WNR_RET IaaWnr_Run(WNR_HANDLE handle, short* pss_audio_in);

Parameter

Parameter name Description Input/Output

handle Algorithm handle Input

pss_audio_in Input data pointer Input
Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A

Example

#include <stdio.h>
#include <string.h>
#include <time.h>
#include <stdlib.h>
#ifndef OS_WINDOWS
#include <sys/ioctl.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>

#include "AudioWnrProcess.h"

#define USE_MALLOC   (1)
unsigned int WorkingBuffer2[1] = {0};

typedef unsigned char                uint8;
typedef unsigned short               uint16;
typedef unsigned long                uint32;

float AVERAGE_RUN(int a)
{
    static unsigned int num = 0;
    static float avg = 0;
    if(num == 0) avg = 0;
    num++;
    avg = avg + ((float)a - avg) / ((float)num);
    return avg;
}
unsigned int _OsCounterGetMs(void)
{
    struct  timeval t1;
    gettimeofday(&t1,NULL);
    unsigned int T = ( (1000000 * t1.tv_sec)+ t1.tv_usec );
    return T;
}

int main(int argc, char *argv[])
{
    short input[1024];
    char input_file[512];
    char outfile_name[512];
    unsigned int T0, T1;
    float avg = 0;
    int counter=0;
#if USE_MALLOC
    char *working_buf_ptr = (char*)malloc(IaaWnr_GetBufferSize());
#else
    char working_buf_ptr[512*100*2];
#endif

    FILE * fin, *fout;
    int ret1;

    WNR_HANDLE handle;
    AudioWnrInit wnr_init;
    AudioWnrConfig wnr_config;

    char wnr_para_json_file[512];
    sprintf(wnr_para_json_file,"%s","./../sample/data/WnrParamJson.json");
    unsigned int wnr_para_buffersize = IaaWnr_GetJsonFileSize(wnr_para_json_file);
    char *wnr_para_json_buf_ptr = (char*)malloc(wnr_para_buffersize);

    memset(&wnr_init,0,sizeof(AudioWnrInit));
    memset(&wnr_config,0,sizeof(AudioWnrConfig));

    ret1 = IaaWnr_InitReadFromJson(&wnr_init, wnr_para_json_buf_ptr, wnr_para_json_file, wnr_para_buffersize);
    ret1 = IaaWnr_ConfigReadFromJson(&wnr_config, wnr_para_json_buf_ptr, wnr_para_json_file, wnr_para_buffersize);

    if(ret1 < 0)
    {
        printf("Error occured Read JSON file\n");
        return -1;
    }

    handle = IaaWnr_Init((char *)working_buf_ptr, &wnr_init);
    if(handle==NULL)
    {
        printf("WNR init error\r\n");
        return -1;
    }
    else
    {
        printf("WNR init succeed\r\n");
    }

    if(IaaWnr_Config(handle, &wnr_config) == -1)
    {
        printf("Config Error!");
        return -1;
    }

    sprintf(input_file,"%s","./../sample/data/m5dB_p228_217_mic1_test_gusts_07.wav");
    sprintf(outfile_name,"%s","./../sample/data/m5dB_p228_217_mic1_test_gusts_07_sim.wav");

    fin = fopen(input_file, "rb");
    if(!fin)
    {
        printf("the input file %s could not be open\n",input_file);
        return -1;
    }

    fout = fopen(outfile_name, "wb");
    if (!fout)
    {
        fprintf(stderr, "Error opening file: %s\n", outfile_name);
        return -1;
    }

    fread(input, sizeof(char), 44, fin); // read header 44 bytes
    fwrite(input, sizeof(char),44, fout); // write 44 bytes output

    while(fread(input, sizeof(short), wnr_init.point_number*wnr_init.channel, fin))
    {

        counter++;
        T0  = (long)_OsCounterGetMs();
        ret1 = IaaWnr_Run(handle, input);
        T1  = (long)_OsCounterGetMs();
        avg += (T1 - T0);

        if(ret1 < 0)
        {
            printf("Error occured in WNR\n");
            break;
        }

        fwrite(input, sizeof(short), wnr_init.point_number*wnr_init.channel, fout);

    }
    avg /= counter;
    printf("AVG is %.2f us\n",avg);
    IaaWnr_Free(handle);
    free(working_buf_ptr);
    fclose(fin);
    fclose(fout);
    printf("Done\n");
return 0;

2.5. IaaWnr_Free¶

Function

Free WNR algorithm resources.

Syntax

ALGO_WNR_RET IaaWnr_Free(WNR_HANDLE handle);

Parameter

Parameter name Description Input/Output

handle WNR algorithm handle Input
Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

IaaWnr_Free must be called first before releasing the memory used by the WNR algorithm
Example

Please refer to IaaWnr_Run example.

2.6. IaaWnr_SetHandleId¶

Function

Set WNR algorithm ID

Syntax

ALGO_WNR_RET IaaWnr_SetHandleId(WNR_HANDLE handle, int id);

Parameter

Parameter name Description Input/Output

handle WNR algorithm handle Input

id WNR algorithm handle id. Value range: [0,100] Input
Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A

2.7. IaaWnr_GetJsonFileSize¶

Function

WNR get size of json file

Syntax

unsigned int IaaWnr_GetJsonFileSize(char* jsonfile);

Parameter

Parameter name Description Input/Output

jsonfile name of json file Input
Return Value

Return value is the memory size required for decoding json file.
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A
Example

Please refer to IaaWnr_Run example.

2.8. IaaWnr_InitReadFromJson¶

Function

Set json parameter into WNR init structure

Syntax

ALGO_WNR_RET IaaWnr_InitReadFromJson(AudioWnrInit* wnr_init, char* jsonBuffer, char* jsonfile, unsigned int buffSize);

Parameter

Parameter name Description Input/Output

wnr_init WNR algorithm Init Input

jsonBuffer json buffer memory address Input

jsonfile name of json file Input

buffSize size of json file Input
Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A
Example

Please refer to IaaWnr_Run example.

2.9. IaaWnr_ConfigReadFromJson¶

Function

Set json parameter into WNR config structure

Syntax

ALGO_WNR_RET IaaWnr_ConfigReadFromJson(AudioWnrConfig* wnr_config, char* jsonBuffer, char* jsonfile, unsigned int buffSize);

Parameter

Parameter name	Description	Input/Output
wnr_config	WNR algorithm Config	Input
jsonBuffer	json buffer memory address	Input
jsonfile	name of json file	Input
buffSize	size of json file	Input

Return Value

Return Value Result

0 Successful

Non-zero Failed, refer to Error code
Dependency
- Header file: AudioWnrProcess.h
- Library file: libWNR_LINUX.so/ libWNR_LINUX.a
Note

N/A
Example

Please refer to IaaWnr_Run example.

3. WNR data type list¶

The relevant data types of the WNR module are defined as follows:

Data Type	Definition
IAA_WNR_SAMPLE_RATE	Sampling rate type of WNR algorithm
WNR_CONVERGE_SPEED	Convergence speed of WNR algorithm
AudioWnrInit	Initialization data structure type of WNR algorithm
AudioWnrConfig	Parameter setting structure type of WNR algorithm
WNR_HANDLE	Define WNR algorithm handle type.

3.1. IAA_WNR_SAMPLE_RATE¶

Description

Define the sampling rate type of the WNR algorithm.

Definition

typedef enum {

    IAA_WNR_SAMPLE_RATE_16000 = 16000 ,

}IAA_WNR_SAMPLE_RATE;

Member

Member name Description

IAA_WNR_SAMPLE_RATE_16000 Sampling rate 16000Hz
Note

N/A
Related Data Type and Interface

AudioWnrInit

3.2. WNR_CONVERGE_SPEED¶

Description

Define the convergence speed of the WNR algorithm.

Definition

typedef enum {

    WNR_SPEED_LOW,

    WNR_SPEED_MID,

    WNR_SPEED_HIGH

} WNR_CONVERGE_SPEED;

Member

Member name Description

WNR_SPEED_LOW Low speed

WNR_SPEED_MID Medium speed

WNR_SPEED_HIGH High speed
Note

N/A
Related Data Type and Interface

AudioWnrConfig

3.3. AudioWnrInit¶

Description

Define the initialization parameter type of the WNR algorithm.

Definition

typedef struct {

    unsigned int point_number;

    unsigned int channel;

    IAA_WNR_SAMPLE_RATE sample_rate;

}AudioWnrInit;

Member

Member name Description

point_number The number of sampling points processed by the WNR algorithm once

channel Channel number, support mono and stereo.

sample_rate Sampling rate
Note
- point_number, MODE1 can support the 128 point and the 256 point (determined at compile time). The point_number supported by library file can be obtained by entering the following command in the terminal
```
 strings libWNR_LINUX.a | grep WNRSET 
```
- sample_rate, MODE1 only supports 16k.
Related Data Type and Interface

IaaWnr_Init

IaaWnr_InitReadFromJson

3.4. AudioWnrConfig¶

Description

Define the configuration parameter structure type of the WNR algorithm.

Definition

typedef struct{

    unsigned int wnr_enable;

    unsigned int wnr_mode;

    int wnr_intensity_band[WNR_BAND_NUM-1];

    int wnr_intensity[WNR_BAND_NUM];

    unsigned int wnr_smooth_level;

    WNR_CONVERGE_SPEED wnr_converge_speed;

}AudioWnrConfig;

Member

Member name	Description
wnr_enable	Disable/Enable WNR algorithm
wnr_mode	WNR filter mode. Rang [0,1]. Step size: 1
wnr_intensity_band	WNR frequency range.Range [1,point_number]. Step size: 1
wnr_intensity	Supress instensity.The larger the value, the higher the wnr. But at the same time it will also bring about the loss/damage of details. The recommended value is 10. Range [0,30]. Step size: 1
wnr_smooth_level	Frequency domain smoothness. Recommended value: 0 Range [0,10]. Step size: 1
wnr_converge_speed	Wind noise convergence speed. Recommended value: high. Range [low;mid;high]

Note
- When wnr_enable is FALSE, the algorithm does not take action and other WNR parameters will not take effect.
- wnr_mode specifies WNR algorithm 1 is the wind noise reduction algorithm using deep learning. The algorithm mode that can be used by library file can be found by entering the following command in the terminal
```
 strings libWNR_LINUX.a | grep WNRTYPE 
```
- wnr_intensity_band/wnr_intensity/wnr_smooth_level/wnr_converge_speed is the tuning parameter of wnr_mode 1.
- WNR_BAND_NUM Definition can be viewed from header.
- wnr_intensity_band, noise reduction frequency range, the next element must be greater than or equal to the previous element.
  
  For example: wnr_intensity_band[0] = 10, then: wnr_intensity_band[1] must be greater than or equal to 10.
  
  The highest frequency corresponding to the current sampling rate is evenly divided into point_number parts, and the frequency range is the corresponding number of parts that form a frequency band.
  
  For example: the current point_number is 128, the sampling rate is 16K, the corresponding maximum frequency is 8K, and each part is 8000 / 128 ≈ 62.5 Hz. For example, under the settings of {4, 6, 36, 49, 50, 51}, the noise reduction frequency range is {0 ~ 4 * 62.5Hz, 4 ~ 6 * 62.5Hz, 6 ~ 36 * 62.5Hz, 36 ~ 49 * 62.5Hz, 49 ~ 50 * 62.5Hz, 50 ~ 51 * 62.5Hz, 51-127 * 62.5Hz} = {0 ~ 250Hz, 250 ~ 375Hz, 375 ~ 2250Hz, 2250 ~ 3062.5Hz, 3062.5 ~ 3125Hz, 3125 ~ 3187.5Hz, 3187.5Hz ~ 8000Hz}. wnr_intensity is the wind noise reduction intensity, which can be divided according to the frequency band of wnr_intensity_band, and different parameters can be set according to the noise situation of each frequency band.
- wnr_smooth_level, WNR algorithm handles the smoothness in the frequency domain and smoothes the suppression on adjacent frequencies.
- wnr_converge_speed, the convergence speed of the WNR algorithm, that is the speed of updating noise. The slower the setting, the slower the noise reduction convergence.
Related Data Type and Interface

IaaWnr_Config

IaaWnr_ConfigReadFromJson

3.5. WNR_HANDLE¶

Description

Define WNR algorithm handle type.
Definition

typedef void* WNR_HANDLE;
Member

Member name Description

N/A
Note

N/A
Related Data Type and Interface

IaaWnr_Init

IaaWnr_Config

IaaWnr_Run

IaaWnr_Free

IaaWnr_SetHandleId

4. Error code¶

WNR API error codes are shown as follow：

error code	Definition	Description
0x00000000	ALGO_WNR_RET_SUCCESS	WNR execute Successful
0x10000801	ALGO_WNR_RET_INVALID_CONFIG	WNR Config setting is invalid
0x10000802	ALGO_WNR_RET_INVALID_HANDLE	WNR Handle is invalid
0x10000803	ALGO_WNR_RET_INVALID_SAMPLERATE	WNR Sample rate setting is invalid
0x10000804	ALGO_WNR_RET_INVALID_POINTNUMBER	WNR point number setting is invalid
0x10000805	ALGO_WNR_RET_INVALID_CHANNEL	WNR channel setting is invalid
0x10000806	ALGO_WNR_RET_INVALID_ENABLE	WNR enable setting is invalid
0x10000807	ALGO_WNR_RET_INVALID_MODE	WNR mode setting is invalid
0x10000808	ALGO_WNR_RET_INVALID_INTENSITY	WNR intensity setting is invalid
0x10000809	ALGO_WNR_RET_INVALID_SMOOTH_LEVEL	WNR smooth level setting is invalid
0x10000810	ALGO_WNR_RET_INVALID_CONVERGE_SPEED	WNR convergence speed setting is invalid
0x10000811	ALGO_WNR_RET_INVALID_JSONFILE	WNR json releated error
0x10000812	ALGO_WNR_RET_INVALID_DUMP	WNR Dump file related error
0x10000813	ALGO_WNR_RET_INVALID_CALLING	Incorrect order of calling WNR API
0x10000814	ALGO_WNR_RET_API_CONFLICT	Other WNR APIs are running
0x10000815	ALGO_WNR_RET_FAILED	WNR execute failed

Parameter name	Description	Input/Output
working_buffer_address	Memory address used by WNR algorithm	Input
wnr_init	WNR algorithm initialization structure pointer	Input

Parameter name	Description	Input/Output
handle	WNR algorithm handle	Input
wnr_config	WNR algorithm parameter setting structure	Input

Parameter name	Description	Input/Output
handle	Algorithm handle	Input
pss_audio_in	Input data pointer	Input

Parameter name	Description	Input/Output
wnr_init	WNR algorithm Init	Input
jsonBuffer	json buffer memory address	Input
jsonfile	name of json file	Input
buffSize	size of json file	Input

Member name	Description
WNR_SPEED_LOW	Low speed
WNR_SPEED_MID	Medium speed
WNR_SPEED_HIGH	High speed

Member name	Description
point_number	The number of sampling points processed by the WNR algorithm once
channel	Channel number, support mono and stereo.
sample_rate	Sampling rate

Return Value	Result
Non-NULL	Successful
NULL	Failed

Return Value	Result
0	Successful
Non-zero	Failed, refer to Error code

Return Value	Result
0	Successful
Non-zero	Failed, refer to Error code

Return Value	Result
0	Successful
Non-zero	Failed, refer to Error code