eprintid: 1609 rev_number: 7 eprint_status: archive userid: 6 dir: disk0/00/00/16/09 datestamp: 2013-06-10 08:42:23 lastmod: 2013-06-10 08:42:23 status_changed: 2013-06-10 08:42:23 type: conference_item metadata_visibility: show creators_name: Rusu, Cristian creators_name: Dumitrescu, Bogdan creators_id: cristian.rusu@imtlucca.it creators_id: title: Stagewise K-SVD to Design Efficient Dictionaries for Sparse Representations ispublished: unpub subjects: QA75 divisions: CSA full_text_status: none pres_type: paper keywords: classification, coding, dataset, dictionaries, error constraint, pattern recognition, sparse representations, stagewise K-SVD abstract: The problem of training a dictionary for sparse representations from a given dataset is receiving a lot of attention mainly due to its applications in the fields of coding, classification and pattern recognition. One of the open questions is how to choose the number of atoms in the dictionary: if the dictionary is too small then the representation errors are big and if the dictionary is too big then using it becomes computationally expensive. In this letter, we solve the problem of computing efficient dictionaries of reduced size by a new design method, called Stagewise K-SVD, which is an adaptation of the popular K-SVD algorithm. Since K-SVD performs very well in practice, we use K-SVD steps to gradually build dictionaries that fulfill an imposed error constraint. The conceptual simplicity of the method makes it easy to apply, while the numerical experiments highlight its efficiency for different overcomplete dictionaries. date: 2013 date_type: published pagerange: 1-3 event_title: ICASSP 2013 event_location: Vancouver, Canada event_dates: May 26-31, 2013 event_type: conference refereed: TRUE related_url_url: http://www.icassp2013.com/Papers/AcceptedPapers.asp related_url_type: org citation: Rusu, Cristian and Dumitrescu, Bogdan Stagewise K-SVD to Design Efficient Dictionaries for Sparse Representations. In: ICASSP 2013, May 26-31, 2013, Vancouver, Canada pp. 1-3. (Unpublished) (2013)