Btukfyl

My friend asked me to write a simple program that captures a fingerprint from the built-in reader on a computer and prints out some kind of identifier. I can choose operating system myself, like a laptop with Windows or Linux, or an Android phone.

I thought that would be simple, surely there are many API:s for this, and I noticed that Microsoft themselves actually provides an API for it. Since I can log into my win10 laptop with the fingerprint reader, I know that the reader works.

For some reason the example that Microsoft themselves provide in their documention does not work for me. https://docs.microsoft.com/en-us/windows/desktop/api/Winbio/nf-winbio-winbiocapturesample

I suppose that the people writing those pages forgot to mention some important aspect or step, perhaps there is a way to add permission somewhere in Visual Studio.

After rewriting and trying many things, at least I get ONE step further in the process, but it still fails.

Here is the current version

#include "pch.h"

#include <iostream>

#include "Windows.h"

#include "Stdio.h"

#include "Conio.h"

#include "Winbio.h"

HRESULT CaptureSample();

void capture(WINBIO_SESSION_HANDLE sessionHandle, int flag);



int main()

{

    std::cout << "Hello World!n";

    HRESULT x = CaptureSample();

}



HRESULT CaptureSample()

{

    HRESULT hr = S_OK;

    WINBIO_SESSION_HANDLE sessionHandle = NULL;

    WINBIO_REJECT_DETAIL rejectDetail = 0;

    // Connect to the system pool. 

    hr = WinBioOpenSession(

        WINBIO_TYPE_FINGERPRINT,    // Service provider

        WINBIO_POOL_SYSTEM,         // Pool type

        WINBIO_FLAG_DEFAULT,            // Access: Capture raw data

        NULL,                       // Array of biometric unit IDs

        0,                          // Count of biometric unit IDs

        WINBIO_DB_DEFAULT,          // Default database

        &sessionHandle              // [out] Session handle

    );

    if (FAILED(hr))

    {

        wprintf_s(L"WinBioOpenSession failed. hr = 0x%xn", hr);

        goto e_Exit;

    }



    wprintf_s(L"Start my fingerprint capturing...n");

    capture(sessionHandle, WINBIO_DATA_FLAG_INTEGRITY);

    capture(sessionHandle, WINBIO_DATA_FLAG_PRIVACY);

    capture(sessionHandle, WINBIO_DATA_FLAG_SIGNED);

    capture(sessionHandle, WINBIO_DATA_FLAG_OPTION_MASK_PRESENT);

    capture(sessionHandle, WINBIO_DATA_FLAG_RAW);

    capture(sessionHandle, WINBIO_DATA_FLAG_INTERMEDIATE);

    capture(sessionHandle, WINBIO_DATA_FLAG_PROCESSED);

    hr = WinBioEnrollCapture(sessionHandle, &rejectDetail);

    wprintf_s(L"WinBioEnrollCapture hr=%x rejection = %dn", hr, rejectDetail);



    if (sessionHandle != NULL)

    {

        WinBioCloseSession(sessionHandle);

        sessionHandle = NULL;

    }



e_Exit:

    wprintf_s(L"n Press any key to exit...");

    _getch();



    return hr;



}



void capture(WINBIO_SESSION_HANDLE sessionHandle, int flag) {

    WINBIO_UNIT_ID unitId = 0;

    WINBIO_REJECT_DETAIL rejectDetail = 0;

    PWINBIO_BIR sample = NULL;

    SIZE_T sampleSize = 0;

    wprintf_s(L"n Calling WinBioCaptureSample. Flag = %d.n", flag);

    HRESULT hr = WinBioCaptureSample(

        sessionHandle,

        WINBIO_PURPOSE_IDENTIFY,

        flag,

        &unitId,

        &sample,

        &sampleSize,

        &rejectDetail

    );

    if (FAILED(hr))

    {

        if (hr == WINBIO_E_BAD_CAPTURE)

        {

            wprintf_s(L"n Bad capture; reason: %dn", rejectDetail);

        }

        else if (hr == E_ACCESSDENIED)

        {

            wprintf_s(L"n WinBioCaptureSample failed, access denied.");

        }

        else

        {

            wprintf_s(L"n WinBioCaptureSample failed. hr = 0x%xn", hr);

        }

        goto e_Exit;

    }



    wprintf_s(L"n Swipe processed - Unit ID: %dn", unitId);

    wprintf_s(L"n Captured %d bytes.n", sampleSize);



e_Exit:

    if (sample != NULL)

    {

        WinBioFree(sample);

        sample = NULL;

    }





}

and here is the result of running it:

Hello World!

Start my fingerprint capturing...



 Calling WinBioCaptureSample. Flag = 1.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 2.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 4.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 8.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 32.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 64.



 WinBioCaptureSample failed, access denied.

 Calling WinBioCaptureSample. Flag = 128.



 WinBioCaptureSample failed, access denied.WinBioEnrollCapture hr=8009802c rejection = 0



 Press any key to exit...

What am I missing?

I think you should try using another API, though your objective is not clear here. You can check the CloudABIS™ which is superscalar, biometrics-as-a-service (BaaS) matching system for fast deployment at lower costs. The API is provided by M2SYS TEchnology and they have an vast array of hardware also.