Quickly implement spoofing-resistant face recognition without a Cloud connection
VIZN_RecognizeEvent(gApiHandle, face_info); } break;
static void EvtHandler(ImageFrame_t *frames[], OASISLTEvt_t evt, OASISLTCbPara_t *para, void *user_ data) { [code redacted for simplification] case OASISLT_EVT_QUALITY_CHK_COMPLETE: { UsbShell_Printf(“[OASIS]:quality chk res:%d\ r\n”, para->qualityResult); pQMsg->msg.info.irLive = para->reserved[5]; pQMsg->msg.info.front = para->reserved[1]; pQMsg->msg.info.blur = para->reserved[3]; pQMsg->msg.info.rgbLive = para->reserved[8];
{ UsbShell_DbgPrintf(VERBOSE_MODE_L2,
if (diff > 1000000 / PIT_TIMER_UNIT) { // update fps pQMsg->msg.info.recognize_fps = timeState-
“[EVT]: Blurry Face!\r\n”); }
else if (para->qualityResult == OASIS_QUALITY_
>rec_fps * 1000.0f / diff;
Listing 3. As shown in this snippet from a sample application in the NXP software distribution, an event handler processes events encountered during the face recognition sequence. Code source: NXP
RESULT_FAIL_LIVENESS_IR) {
timeState->rec_fps = 0; timeState->rec_fps_start = timeState-
UsbShell_DbgPrintf(VERBOSE_MODE_L2,
>rec_comp; } #endif
“[EVT]: IR Fake Face!\r\n”); }
verification for production.
else if (para->qualityResult == OASIS_QUALITY_
Along with the runtime environment and associated sample application code, NXP provides Android mobile apps with full java source code. One app, the VIZNAS FaceRec Manager, provides a simple interface for registering faces and managing users. Another app, the VIZNAS Companion app, allows users to provision the kit with Wi-Fi credentials using an existing Wi-Fi or BLE connection. Conclusion Face recognition offers an effective approach for authenticating access to smart products, but implementing it has typically required local high- performance computing or always-on high-bandwidth connectivity for rapid responses. It has also been a target of spoofing and is subject to concerns about user privacy. As shown, a specialized processor and software library from NXP Semiconductors offer an alternative approach that can accurately perform offline face recognition in less than a second without a Cloud connection, while mitigating spoofing attempts.
memset(pQMsg->msg.info.name, 0x0,
RESULT_FAIL_LIVENESS_RGB) {
sizeof(pQMsg->msg.info.name));
UsbShell_DbgPrintf(VERBOSE_MODE_L2,
if (recResult == OASIS_REC_RESULT_KNOWN_
“[EVT]: RGB Fake Face!\r\n”); } } break; [code redacted for simplification]
FACE)
{
if (para->qualityResult == OASIS_QUALITY_
RESULT_FACE_OK_WITHOUT_GLASSES ||
std::string name; UsbShell_DbgPrintf(VERBOSE_MODE_L2,
para->qualityResult == OASIS_QUALITY_
RESULT_FACE_OK_WITH_GLASSES) {
“[OASIS]:face id:%d\r\n”, id);
case OASISLT_EVT_REC_COMPLETE: { int diff; unsigned id = para->faceID; OASISLTRecognizeRes_t recResult = para- >recResult;
DB_GetName(id, name); memcpy(pQMsg->msg.info.name, name.c_
UsbShell_DbgPrintf(VERBOSE_MODE_L2,
“[EVT]:ok!\r\n”); }
str(), name.size());
face_info.recognize = true; face_info.name = std::string(name); UsbShell_DbgPrintf(VERBOSE_MODE_L2, “[OASIS]:face id:%d name:%s\r\n”, id, pQMsg->msg. info.name); } else { // face is not recognized, do nothing UsbShell_DbgPrintf(VERBOSE_MODE_L2, “[OASIS]:face unrecognized\r\n”); face_info.recognize = false; }
else if (OASIS_QUALITY_RESULT_FACE_SIDE_
FACE == para->qualityResult) {
UsbShell_DbgPrintf(VERBOSE_MODE_L2,
timeState->rec_comp = Time_Now(); pQMsg->msg.info.rt = timeState->rec_start -
“[EVT]:side face!\r\n”); }
timeState->rec_comp; face_info.rt
else if (para->qualityResult == OASIS_QUALITY_
= pQMsg->msg.info.rt;
RESULT_FACE_TOO_SMALL) {
#ifdef SHOW_FPS
/*pit timer unit is us*/ timeState->rec_fps++; diff = abs(timeState->rec_fps_start - timeState-
UsbShell_DbgPrintf(VERBOSE_MODE_L2,
“[EVT]:Small Face!\r\n”); }
>rec_comp);
else if (para->qualityResult == OASIS_QUALITY_
RESULT_FACE_BLUR)
we get technical
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