The most critical aspect of global crisis of missing persons is time since the possibility of successful recovery is higher. reduces significantly during thefirst24to48hours. Sincetheissueislargeandurgent, conventionalmethods of investigation that are used are inadequate. mainly dependent on the manual examination of colossal quantities of visual proofs in the types of CCTV recordings andcitizenleads-areessentiallyinsufficient. Theseprocessesaretediousinnature, subject to humanerrorandexhaustion, and they lead to significant operation. bottlenecks stressing law enforcement forces and increasing the misery offamilies.Thisstudy directly deals with this. urgent requirement creating an integrated, machine learning-based pipeline in order to detect and identify missed persons. The proposed modelisnotjustameretool official recognition, butisamulti-algorithmsframeworkwhichisunified. works as a complete detection system. To start with, a detailed analysis of the face is conducted with the help of the mediapipe Face Mesh that is able to. detection of 468 3D face landmarks in real-time. To abstract a face image of a raw array of pixels into a structured/geometricimage.representation,itshouldbe capable of surviving the real world differences in pose, light and image quality. The core of our system uses a hybrid approach to feature extraction, in which geometric features based onfaciallandmarksare extracted using a bespoke, lightweight model. Convolutional Neural Network (CNN). The design allows acquisition of highly discriminative features of landmark spatial. relationships, creating compact, high-fidelity embedding vectors which in a unique way describe the facial geometry of an individual. This approach has high accuracy and computational efficiency needed in resource constrained environments. For identificationisamatchingenginebasedonK-NearestNeighbours(KNN)whichindexesallregistered embeddings into a feature which can be searched. space. When a new query is processed, a similarity search is conducted at a high speed with the help of the algorithm. An adjustable distance. threshold approves the possible matches, which guarantees high confidence and reduces false positives. An efficient and efficient identification. The output of the landmark detection, deep feature extraction, and efficient similarity search are a combination of workflow. This work provides an effective resource to bolstercommunityandlawenforcementworkbytransformingaconventionalsearchprocessintoa. Memberof the automated and data-driven procedure. It aims at speeding up the most important job of finding missing persons, reducing thetimeofinvestigations, and increase success rates.
Introduction
The text addresses the urgent global issue of missing persons, emphasizing that the first 48–72 hours are critical for recovery. Traditional investigation methods, such as manual analysis of CCTV footage, are slow, inefficient, and prone to human error, creating a need for automated, intelligent systems.
To address this, the study proposes a machine learning–based facial recognition system that automates identification using deep learning and geometric facial features. Unlike heavy models like FaceNet, the system balances accuracy and efficiency by combining MediaPipe Face Mesh (for extracting 468 facial landmarks) with a lightweight CNN to generate feature embeddings, and a K-Nearest Neighbors (KNN) algorithm with a dynamic threshold for accurate matching.
The methodology involves preprocessing images, extracting landmarks, generating embeddings, and performing fast similarity searches using Ball Tree indexing. The system is implemented using tools like TensorFlow, OpenCV, and Streamlit, enabling real-time, scalable, and low-cost deployment.
Results show that the system significantly reduces identification time from days to minutes, while maintaining high accuracy with low computational cost. Key advantages include efficiency, scalability, robustness to real-world variations, privacy preservation, and explainability.
However, limitations include reduced performance with heavy occlusion, lack of age progression handling, and reliance on frontal images. Future improvements include adding multimodal biometrics, GAN-based age adaptation, federated learning, and real-time CCTV integration.
Conclusion
This paper introduces a new hybrid machine learning pipeline to identify missing persons automatically, whichcan be effective in terms of accuracy, computational efficiency,andprivacyprotection.Thesystemcanbetrained with MediaPipe Face Mesh to extract geometric landmarks and a small CNN to generate discriminative embeddings in order to reach competitiveaccuracyandstillbedeployedon resource-constrained devices. The K-Nearest Neighbors matching engine is matched with Ball Tree indexing that guarantees identifying large databases in real time that are scalable. [14]
The suggested framework addresses the most important constraints of the current solutions namely: the computational complexity of contemporary deep learning models and the ineffectiveness of traditional manual investigation methods. This system can significantly reduce the length of time usedininvestigations,increasetherateof recoveries and provide law enforcement agencies with a powerful tool to combat the problem of missing persons around the globe as byturningatime-sensitivesearchintoa data-driven and automated process.It is placed as a modular, morally responsible contribution to the applied machine learning discipline in the area of public safety due toitsexplainablegeometricrepresentationsand privacy-sensitive design. [4].
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