TY - GEN
T1 - Learning doubly sparse transforms for image representation
AU - Ravishankar, Saiprasad
AU - Bresler, Yoram
PY - 2012
Y1 - 2012
N2 - The sparsity of images in a fixed analytic transform domain or dictionary such as DCT or Wavelets has been exploited in many applications in image processing including image compression. Recently, synthesis sparsifying dictionaries that are directly adapted to the data have become popular in image processing. However, the idea of learning sparsifying transforms has received only little attention. We propose a novel problem formulation for learning doubly sparse transforms for signals or image patches. These transforms are a product of a fixed, fast analytic transform such as the DCT, and an adaptive matrix constrained to be sparse. Such transforms can be learnt, stored, and implemented efficiently. We show the superior promise of our approach as compared to analytical sparsifying transforms such as DCT for image representation.
AB - The sparsity of images in a fixed analytic transform domain or dictionary such as DCT or Wavelets has been exploited in many applications in image processing including image compression. Recently, synthesis sparsifying dictionaries that are directly adapted to the data have become popular in image processing. However, the idea of learning sparsifying transforms has received only little attention. We propose a novel problem formulation for learning doubly sparse transforms for signals or image patches. These transforms are a product of a fixed, fast analytic transform such as the DCT, and an adaptive matrix constrained to be sparse. Such transforms can be learnt, stored, and implemented efficiently. We show the superior promise of our approach as compared to analytical sparsifying transforms such as DCT for image representation.
KW - Analysis transforms
KW - Dictionary learning
KW - Image representation
KW - Sparse representation
KW - Structured transforms
UR - http://www.scopus.com/inward/record.url?scp=84875861443&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875861443&partnerID=8YFLogxK
U2 - 10.1109/ICIP.2012.6466952
DO - 10.1109/ICIP.2012.6466952
M3 - Conference contribution
AN - SCOPUS:84875861443
SN - 9781467325332
T3 - Proceedings - International Conference on Image Processing, ICIP
SP - 685
EP - 688
BT - 2012 IEEE International Conference on Image Processing, ICIP 2012 - Proceedings
T2 - 2012 19th IEEE International Conference on Image Processing, ICIP 2012
Y2 - 30 September 2012 through 3 October 2012
ER -