Consiglio Nazionale delle Ricerche

Tipo di prodottoArticolo in rivista
TitoloCurl-Constrained Gradient Estimation for Image Recovery From Highly Incomplete Spectral Data
Anno di pubblicazione2017
Autore/iRavazzi, Chiara; Coluccia, Giulio; Magli, Enrico
Affiliazioni autoriCNR IEIIT; Politecnico Torino; Politecnico di Torino;
Autori CNR e affiliazioni
  • inglese
AbstractIn this paper, we introduce new gradient-based methods for image recovery from a small collection of spectral coefficients of the Fourier transform, which is of particular interest for several scanning technologies, such as magnetic resonance imaging. Since gradients of a medical image are much more sparse or compressible than the corresponding image, classical l(1)-minimization methods have been used to recover these relative differences. The image values can then be obtained by integration algorithms imposing boundary constraints. Compared with classical gradient recovery methods, we propose two new techniques that improve reconstruction. First, we cast the gradient recovery problem as a compressed sensing problem taking into account that the curl of the gradient field should be zero. Second, inspired by the emerging field of signal processing on graphs, we formulate the gradient recovery problem as an inverse problem on graphs. Iteratively reweighted l(1) recovery methods are proposed to recover these relative differences and the structure of the similarity graph. Once the gradient field is estimated, the image is recovered from the compressed Fourier measurements using least squares estimation. Numerical experiments show that the proposed approach outperforms the state-of- the-art image recovery methods.
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Pagine da2656
Pagine a2668
Pagine totali13
RivistaIEEE transactions on image processing
Attiva dal 1992
Editore: Institute of Electrical and Electronics Engineers, - New York, NY
Paese di pubblicazione: Stati Uniti d'America
Lingua: inglese
ISSN: 1057-7149
Titolo chiave: IEEE transactions on image processing
Titolo proprio: IEEE transactions on image processing
Titolo abbreviato: IEEE trans. image process.
Titoli alternativi:
  • Institute of Electrical and Electronics Engineers transactions on image processing
  • Image processing
Numero volume della rivista26
Fascicolo della rivista6
Verificato da refereeSì: Internazionale
Stato della pubblicazionePostprint
Indicizzazione (in banche dati controllate)
  • ISI Web of Science (WOS) (Codice:000401296100007)
Parole chiaveCompressed sensing, Fourier transform, sparse recovery, spectral graph theory, total variation
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Strutture CNR
  • IEIIT — Istituto di elettronica e di ingegneria dell'informazione e delle telecomunicazioni
Moduli CNR
    Progetti Europei
    • Curl-Constrained Gradient Estimation for Image Recovery From Highly Incomplete Spectral Data
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