Keyphrases
- sparse representation
- face recognition
- dictionary learning
- sparse coding
- image patches
- compressed sensing
- subspace learning
- face images
- sparse approximations
- compressive sensing
- sparse reconstruction
- image classification
- sample size
- object tracking
- joint optimization
- reconstruction error
- regularized least squares
- piecewise smooth
- facial expressions
- norm minimization
- linear discriminant analysis
- random projections
- image representation
- feature extraction
- high dimensional data
- negative matrix factorization
- feature space
- image processing
- human faces
- sparse codes
- data sets
- illumination variations
- knn
- principal component analysis
- face recognition systems
- test images
- natural images
- sparse representation based classification
- sparse coefficients