Table 1 Summary of literature review.

From: A hybrid CNN-transformer framework optimized by Grey Wolf Algorithm for accurate sign language recognition

Study

Algorithm(s) used

Problem addressed

Key features

Limitations

15

CNNSa-LSTM

Spatial–temporal gesture recognition

Attention-based CNN, LSTM for sequences

Risk of overfitting on small datasets

17

AEGWO-Net (Autoencoder + GWO)

Dimensionality reduction and feature optimization in ASLR

High accuracy, adaptive GWO parameters, validated on 6 datasets

Still face challenges in real-time applications

18

Lightweight CNN

Real-time gesture recognition

Low computational cost, embedded deployment

Limited temporal modeling

20

Dual-view Transformer

Occlusion-aware SLR with multi-view inputs

Pose integration, egocentric data capture

Needs extensive training data

23

Ego-SLD (CNN-LSTM)

Egocentric dynamic SLR

Realistic dataset, wearable capture

Requires synchronization and noise control

25

Skeleton + Self-attention

Manual and non-manual gesture modeling

High accuracy on AUTSL, multi-modal

Complex model integration

40

GWO for CNN tuning

CNN architecture optimization

Faster training, improved generalization

Parameter sensitivity