PIBIO_ENGINE_CHECK_FOR_DUPLICATE_FN回呼函式 (winbio_adapter.h)
由 Windows 生物特徵辨識架構呼叫,以判斷管線中的新範本是否複製任何已經儲存在資料庫中的範本,而不論與範本相關聯的身分識別為何。
語法
PIBIO_ENGINE_CHECK_FOR_DUPLICATE_FN PibioEngineCheckForDuplicateFn;
HRESULT PibioEngineCheckForDuplicateFn(
[in, out] PWINBIO_PIPELINE Pipeline,
[out] PWINBIO_IDENTITY Identity,
[out] PWINBIO_BIOMETRIC_SUBTYPE SubFactor,
[out] PBOOLEAN Duplicate
)
{...}
參數
[in, out] Pipeline
與執行作業之生物特徵辨識單位相關聯的 WINBIO_PIPELINE 結構的指標。
[out] Identity
WINBIO_IDENTITY 結構的指標,該結構會接收儲存在資料庫中之重複範本的 GUID 或 SID。
[out] SubFactor
WINBIO_BIOMETRIC_SUBTYPE變數的指標,該變數會接收與資料庫中重複範本相關聯的子因素。
[out] Duplicate
布爾值的指標,指定是否在資料庫中找到相符的範本。
傳回值
傳回碼 | Description |
---|---|
|
強制指標參數為 NULL。 |
|
管線引擎內容中沒有註冊範本。 |
備註
Windows 生物特徵辨識架構會先呼叫此函式,再將新的註冊範本認可至生物特徵辨識單位的資料庫。 此函式的目的是防止引擎配接器比對空間發生衝突。 衝突可能會導致誤判相符專案。
此函式應該使用記憶體配接器來執行以內容為基礎的查詢,以判斷範本是否符合資料庫中已有的任何範本。
如果這個方法在資料庫中找到重複的範本,它應該傳回相符範本的 Identity 和 SubFactor 值、將 Duplicate 參數設定為 TRUE,並傳回 hrESULT 值S_OK。
如果這個方法在資料庫中找不到相符的範本,它應該將 Duplicate 參數設定為 FALSE ,但會傳回S_OK的 HRESULT 值。
範例
下列虛擬程式代碼顯示此函式的一個可能實作。 此範例不會編譯。 您必須調整它以符合您的用途。
//////////////////////////////////////////////////////////////////////////////////////////
//
// EngineAdapterCheckForDuplicate
//
// Purpose:
// Determines whether a new template in the pipeline duplicates any
// template already saved in the database regardless of the identity
// associated with the templates.
//
// Parameters:
// Pipeline - Pointer to a WINBIO_PIPELINE structure associated
// with the biometric unit performing the operation
// Identity - GUID or SID of the duplicate template stored in the
// database
// SubFactor - sub-factor associated with the duplicate template in
// the database
// Duplicate - Boolean value that specifies whether a matching template
// was found in the database
//
static HRESULT
WINAPI
EngineAdapterCheckForDuplicate(
__inout PWINBIO_PIPELINE Pipeline,
__out PWINBIO_IDENTITY Identity,
__out PWINBIO_BIOMETRIC_SUBTYPE SubFactor,
__out PBOOLEAN Duplicate
)
{
HRESULT hr = S_OK;
WINBIO_REJECT_DETAIL rejectDetail = 0;
SIZE_T recordCount = 0;
SIZE_T index = 0;
WINBIO_STORAGE_RECORD thisRecord;
BOOLEAN match = FALSE;
DWORD indexVector[NUMBER_OF_TEMPLATE_BINS] = {0};
// Verify that pointer arguments are not NULL.
if (!ARGUMENT_PRESENT(Pipeline) ||
!ARGUMENT_PRESENT(Identity) ||
!ARGUMENT_PRESENT(SubFactor) ||
!ARGUMENT_PRESENT(Duplicate))
{
hr = E_POINTER;
goto cleanup;
}
// Retrieve the context from the pipeline.
PWINBIO_ENGINE_CONTEXT context =
(PWINBIO_ENGINE_CONTEXT)Pipeline->EngineContext;
// Return if an enrollment is not in progress. This example assumes that
// an enrollment object is part of your engine context structure.
if (context->Enrollment.InProgress != TRUE)
{
hr = WINBIO_E_INVALID_DEVICE_STATE;
goto cleanup;
}
// Zero the memory pointed to by the Identity argument and set the
// pointer to NULL.
ZeroMemory( Identity, sizeof(WINBIO_IDENTITY));
Identity->Type = WINBIO_ID_TYPE_NULL;
// Eliminate sub-factor information.
*SubFactor = WINBIO_SUBTYPE_NO_INFORMATION;
// Initialize the Boolean Duplicate argument to FALSE.
*Duplicate = FALSE;
// If your adapter supports index vectors to place templates into buckets,
// call a custom function (_AdapterCreateIndexVector) to create an index
// vector from the template data in the feature set. In this example, the
// engine adapter context attached to the pipeline contains an Enrollment
// member that references the current template. Your implementation may
// differ.
hr = _AdapterCreateIndexVector(
context,
context->Enrollment.Template,
context->Enrollment.TemplateSize,
indexVector,
NUMBER_OF_TEMPLATE_BINS,
&rejectDetail
);
if (FAILED(hr))
{
goto cleanup;
}
// Retrieve the records in the index vector. If your adapter does not support
// index vectors (the vector length is zero), calling the WbioStorageQueryByContent
// function will retrieve all records.
// WbioStorageQueryByContent is a wrapper function in the Winbio_adapter.h
// header file.
hr = WbioStorageQueryByContent(
Pipeline,
WINBIO_SUBTYPE_ANY,
indexVector,
NUMBER_OF_TEMPLATE_BINS
);
if (FAILED(hr))
{
goto cleanup;
}
// Determine the size of the result set. WbioStorageGetRecordCount is a wrapper
// function in the Winbio_adapter.h header file.
hr = WbioStorageGetRecordCount( Pipeline, &recordCount);
if (FAILED(hr))
{
goto cleanup;
}
// Point the result set cursor at the first record. WbioStorageFirstRecord
// is a wrapper function in the Winbio_adapter.h header file.
hr = WbioStorageFirstRecord( Pipeline );
if (FAILED(hr))
{
goto cleanup;
}
// Iterate through all records in the result set and determine which record
// matches the current feature set. WbioStorageGetCurrentRecord is a wrapper
// function in the Winbio_adapter.h header file.
for (index = 0; index < recordCount; ++index)
{
hr = WbioStorageGetCurrentRecord( Pipeline, &thisRecord );
if (FAILED(hr))
{
goto cleanup;
}
// Call a custom function (_AdapterCompareTemplateToCurrentFeatureSet) to
// compare the feature set attached to the pipeline with the template
// retrieved from storage.
// If the template and feature set match, return S_OK and set the match
// argument to TRUE. If the template and feature set do not match, return
// S_OK and set the match argument to FALSE. If the function fails for some
// other reason, return a failure HRESULT.
hr = _AdapterCompareTemplateToEnrollmentTemplate(
context,
context->Enrollment.Template,
context->Enrollment.TemplateSize,
thisRecord.TemplateBlob,
thisRecord.TemplateBlobSize,
&match
);
if (FAILED(hr))
{
goto cleanup;
}
if (match)
{
break;
}
// Retrieve the next record.
hr = WbioStorageNextRecord( Pipeline );
if (FAILED(hr))
{
if (hr == WINBIO_E_DATABASE_NO_MORE_RECORDS)
{
hr = S_OK;
break;
}
else
{
goto cleanup;
}
}
}
// If there is a duplicate template in the database, return information about
// it to the caller.
if (match)
{
CopyMemory( Identity, thisRecord.Identity, sizeof(WINBIO_IDENTITY));
*SubFactor = thisRecord.SubFactor;
*Duplicate = TRUE;
hr = S_OK;
}
cleanup:
// There are no duplicates. This is an acceptable result.
if (hr == WINBIO_E_DATABASE_NO_RESULTS)
{
hr = S_OK;
}
return hr;
}
規格需求
需求 | 值 |
---|---|
最低支援的用戶端 | Windows 7 [僅限傳統型應用程式] |
最低支援的伺服器 | Windows Server 2008 R2 [僅限傳統型應用程式] |
目標平台 | Windows |
標頭 | winbio_adapter.h (包含 Winbio_adapter.h) |