Quickly implement spoofing-resistant face recognition without a Cloud connection
The sample application can provide developers with step by step debug messages describing the results associated with each event processed by the event handler (EvtHandler). For example, after the quality check completes (OASISLT_EVT_QUALITY_CHK_ COMPLETE), the system prints out debug messages describing the result, and after face recognition completes (OASISLT_EVT_REC_ COMPLETE), the system pulls the
user id and name from its database for recognized faces and prints out that information (Listing 3).
stored in the SLN-VIZNAS-IOT kit’s filesystem. As this verification sequence starts with a trusted bootloader stored in read-only memory (ROM), this process provides a chain of trust for running application firmware. Also, because code signing and verification can slow development, this verification process is designed to be bypassed during software design and debug. In fact, the SLN-VIZNAS- IOT kit comes preloaded with signed images, but code signature verification is bypassed by default. Developers can easily set options to enable full code signature
typedef enum { /*indicate the start of face detection, user can update frame data if it is needed. * all parameter in callback parameter is invalid.*/ OASISLT_EVT_DET_START, /*The end of face detection. *if a face is found, pfaceBox(OASISLTCbPara_t) indicated the rect(left,top,right,bottom point value) *info and landmark value of the face. *if no face is found,pfaceBox is NULL, following event will not be triggered for current frame. *other parameter in callback parameter is invalid */ OASISLT_EVT_DET_COMPLETE,
/*start of emotion recognition*/ OASISLT_EVT_EMO_REC_START,
Besides supporting face recognition processing requirements, the NXP SLN- VIZNAS-IOT software is
/*End of emotion recognition, emoID indicate which emotion current face is.*/ OASISLT_EVT_EMO_REC_COMPLETE,
designed to protect the operating environment. To ensure runtime security, the system is designed to verify the integrity and authenticity of each signed image loaded into the system using a certificate
/*if user set a registration flag in a call of OASISLT_ run and a face is detected, this two events will be notified * for auto registration mode, only new face(not recognized) is added(call AddNewFace callback function) * for manu registration mode, face will be added forcely. * for both cases, face ID of new added face will be set in callback function */ OASISLT_EVT_REG_START, /*when registration start, for each valid frame is handled,this event will be triggered and indicate * registration process is going forward a little. * */
typedef struct { //max input image height, width and channel, min_ face: minimum face can be detected
int height; int width;
/*callback functions provided by caller*/ InfCallbacks_t cbs;
/*Face quality check is done before face recognition*/ OASISLT_EVT_QUALITY_CHK_START, OASISLT_EVT_QUALITY_CHK_COMPLETE,
//only valid for RGB images; for IR image, always GREY888 format OASISLTImageFormat_t img_format; OASISLTImageType_t img_type;
/*what functions should be enabled in OASIS LIB*/ uint8_t enable_flags;
/*Start of face recognition*/ OASISLT_EVT_REC_START,
/*only valid when OASIS_ENABLE_EMO is activated*/ OASISLTEmoMode_t emo_mode;
OASISLT_EVT_REG_IN_PROGRESS, OASISLT_EVT_REG_COMPLETE, OASISLT_EVT_NUM
//min_face should not smaller than 40 int min_face;
/*The end of face recognition. * when face feature in current frame is gotten, GetRegisteredFaces callback will be called to get all * faces feature registered and OASIS lib will try to search this face in registered faces, if this face * is matched, a valid face ID will be set in callback parameter faceID and corresponding simularity(indicate * how confidence for the match) also will be set. * if no face match, a invalid(INVALID_FACE_ID) will be set.*/ OASISLT_EVT_REC_COMPLETE,
/*false accept rate*/ OASISLTFar_t false_accept_rate;
} OASISLTEvt_t;
/*memory pool pointer, this memory pool should only be used by OASIS LIB*/ char* mem_pool;
/*model class */ OASISLTModelClass_t mod_class;
Listing 2. The Oasis Lite runtime recognizes a series of events documented as an enumerated set in the Oasis Lite runtime header file. Code source: NXP
/*memory pool size*/ int size;
} OASISLTInitPara_t;
Listing 1. Developers can modify software execution parameters by modifying the contents of structures such as the one shown here for Oasis Lite runtime initialization. Code source: NXP
/*output parameter,indicate authenticated or not*/ int auth;
we get technical
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