Keyphrases
- sparse representation
- inverse halftoning
- gray scale
- dictionary learning
- image quality
- sparse coding
- face recognition
- gray scale images
- error diffusion
- image classification
- signal processing
- joint optimization
- compressed sensing
- image patches
- compressive sensing
- binary images
- sparse approximations
- dimensionality reduction
- halftone images
- high dimensional data
- image representation
- high quality
- test images
- gray level
- color images
- pattern recognition