Challa Subrahmanya Sastry
Department of Mathematics,
IIT Hyderabad, Pin: 502285.
(AT) math (DOT) iith (DOT) ac (DOT) in
Office: 503, Academic C-Block
Phone (Office): +91 40 2301 6602
BROAD RESEARCH INTERESTS
Sparse Optimization Theory and Inverse Problems
(popularly known as Compressive Sensing) is an interface area
between Algebra and Optimization, which aims at providing some
classes of linear systems with sparse (or economical) descriptions. Applications of this research area are
far and wide in diverse fields including medical imaging.
current research interests lie in Finite frames, Sparsity-seeking
optimization techniques and their applications involving Data-driven
learning methods and Inverse problems. My previous research,
nevertheless, was directed toward Wavelets, Reconstruction in Tomography.
Mathematics Behind Machine Learning
Wavelets & Applications
Theory of Frames
Sparse Representation Theory
Numerical Linear Algebra
Digital Signal Processing
Compressive Sensing (1 credit)
Several UG (B.Tech) level core Math
RESEARCH SCHOLARS/POST-DOCTORAL FELLOWS (Present
Ramunaidu (Currently on
faculty at IIPE
Dr. P. Sasmal (Currently on faculty at IIT
by Dr. Phanindra)
Dr. Prasad Theeda (Currently
on faculty at VIT
by Dr. Phanindra)
Dr. Munnu Sonkar (Currently
PostDoc Fellow at University of Houston, USA)
Dr. K. Z. Najiya (Currently a
PostDoc Fellow at IIT Hyderabad)
Mr. Shantam Gulati (Pursuing
PhD, Co-advised by Dr.
Mr. Akash Sen (Pursuing PhD)
Dr. Praveen Kumar (Former Post
Doc Fellow, Currently a senior
technical architect in IT industry)
Dr. M. P. Ranjan (Former
Post-Doc Felllow, Currently on faculty at IIT (BHU) Varanasi)
Guided 8 M.Sc students and Co-guided 2
M.Tech students for their project works
- “Analysis of general
weights in weighted l1-2- minimization through
applications,” Digital Signal Processing, Vol. 133, 3, 2023
(with K. Z. Najiya)
- “Interior reconstruction
in tomography via prior support constrained compressed sensing,”
Journal of Inverse and Ill-posed Problems, Vol. 31, No. 1,
2023, pp. 77-90 (with M. Sonkar and K. Z. Najiya).
deterministic sampling strategy for coded aperture X-ray computed
tomography,” Measurement Science
and Technology, IoP, Vol. 33, 2022, (with M. Sonkar, P. Sasmal and
- “Local recovery bounds
for prior support constrained compressed sensing,” Mathematical Notes, Springer,
Vol. 111, pp: 93-102, 2022, (with K. Z. Najiya and M. Sonkar).
- “Null space property for
optimality of minimum frame angle under invertible linear operators,” IEEE Signal Processing Letters,
Vol. 28, 1928-1932, 2021 (with P. Sasmal, P. Theeda and P.V. Jampana).
- “Construction of binary
matrices as a union of orthogonal blocks via generalized Euler squares,”
IEEE Signal Processing Letters,
Vol. 28, 882-886, 2021 (with P.
Sasmal, P.V. Jampana).
- “A novel low-complexity
compressed data aggregation method for energy-constrained IoT networks,”
Transactions on Green Communications and Networking, 3, 717-730, 2020.
Amaralingam, P. K. Mishra, P Rajalakshmi, S. S. Channappayya).
- “Ternary matrices
compliant with Restricted Isometry Property: Construction and
Application to image retrieval,” J.
of Combinatorics, Information & System Sciences, Vol. 44, No.
1-4, pages 285-298, 2019. (with R. Naidu and M. Srinivas)
- “Construction of highly
redundant incoherent unit norm tight frames as a union of orthonormal
bases,” Journal of Complexity,
Vol. 54, Oct, 2019 (with P. Sasmal and P. Jampana).
- “Reconstruction of
sparse-view tomography via preconditioned Radon sensing matrix,” J.
of Applied Maths & Comp. Vol. 58, 91-104, 2019 (with P.
Theeda, P. Kumar and P. Jampana).
- “Robust heartbeat detection from
multimodal data via CNN-based generalizable information fusion,” IEEE Transactions on Biomedical
Engineering, Vol. 66, 710 – 717, 2019. (with S. Chandra and S.
- “Novel light weight
compressed data aggregation using sparse measurements for IoT
networks,” Journal of Networks
and Computer Applications, Vol. 121, 119-134, 2018 (with M.
Amaralingam, P. K. Mishra, P Rajalakshmi, S. S. Channappayya).
monitoring of premature ventricular contractions: An ultra-low-cost
point-of-care service,” Artificial Intelligence in Medicine,
Vol. 87, 91-104, 2018 (with B.S. Chandra, L. Anumandla and S. Jana).
- "Composition of
binary compressed sensing matrices," IEEE Signal Processing Letters, Vol. 23, 1096-1100, August
2016, (with P. Sasmal, R. R. Naidu,
Compressed Sensing matrices: Construction via Euler squares and
Transactions on Signal Processing, Vol. 64, 3566-3575, July 2016,
(with R. R.
Naidu, P.V. Jampana)
- "Reliable resource-constrained
Telecardiology via Compressive detection of anomalous ECG signals," Computers in Biology and Medicine, Volume 66, 144-153,
2015 (with S.
Chandra and S. Jana).
- "Content based
medical image retrieval using dictionary learning," Neurocomputing,
Vol. 168, 880-895, 2015 (with M. Srinivas, R. Naidu and C. K. Mohan)
- "In-plane rotation
and scale invariant simultaneous dictionary learning and
clustering," IEEE Transactions on Image
Processing, 22(6), 2013, (with Y. Chen, V. Patel, J. Philips and R. Chellappa)
- "Spectral dynamics and regularization of incompletely and
irregularly measured data," Differential
Equations and Dynamical Systems, Vol. 19(3), pp: 181-197, 2011.
- “Network traffic analysis using singular value decomposition and
multiscale transforms," Information Sciences, Vol. 177,
pp: 5275-5291, December, 2007
(with S. Rawat, A. K. Pujari and V.P. Gulati)
- “A modified Gabor
function for content based image retrieval," Pattern Recognition Letters, Vol. 28, 2, pp: 293-300, 2007 (with M.
Ravindranath, A.K. Pujari, B.L. Deekshatulu).
- “Wavelet based multilevel back
projection algorithm for parallel and fan beam scanning geometries,” Int. J. of Wavelets,
Multiresolution and Information Processing, Vol. 4, N0. 3, pp:
523-545, 2006 (with P.C. Das)
- “A Fourier-Radial
descriptor algorithm for invariant feature extraction,” Int. J. of Wavelets,
Multiresolution and Information processing, Vol. 4, No. 1, pp: 197-212,
2006 (with A. K. Pujari and B. L. Deekshatulu)
- “A convolution
backprojection algorithm for local tomography,” ANZIAM Applied Mathematics, Vol. 46, pp: 341-360, 2005
(with P.C. Das)
- “A wavelet based
multiresolution algorithm for rotation invariant feature extraction,” Pattern Recognition Letters,
Vol. 25, Issue 16, pp: 1845-1855, 2004 (with A.K. Pujari, B.L.
Deekshatulu, C. Bhagvati)
tomography using a composite Fourier-Wavelet algorithm,” Numerical Functional Analysis &
Optimization, Vol. 23, pp:
757-777, 2002 (with P.C. Das)
- “Magnetic resonance
imaging via weighted l1-p minimization” To appear in the
proceedings of 9th PReMI,
ISI Calcutta, 2022, (with K. Z. Najiya).
- “Kernels for incoherent
projection and orthogonal matching pursuit,” To appear in Springer Conf Proceedings, 6th
CVIP, IIT Ropar, 2021 (with Himanshu Kandiyal).
- “Improved performance
guarantees for Orthogonal Matching Pursuit and application to
dimensionality reduction,” In Machine
Vision and Augmented Intelligence—Theory and Applications, Proceedings
of 6th MAI, 2021, (with M. Sonkar and L. Tiwari).
- “Sufficient conditions
for the uniqueness of solution of
the weighted norm minimization problem,” To appear in LNCS, Proc. of 7th
ICMC, 2021 (with K.Z. Najiya and M. Sonkar).
- “Minimally scaled and
incoherent frames,” In Proc. of
IEEE-ICSIP, 2018, China (with P. Theeda, P. Sasmal and P.
- “Reconstruction of
sparse-view tomography via banded matrices, In LNCS, Vol. 10481, In proc. of ICVGIP, IIT
Guwahati, 2016 (with P. Theeda, Praveen Kumar and P. Jampana).
- "On the existence
of equivalence class of RIP compliant matrices, " In Proc. of 11th SampTA,
Washington, May 2015, with P. Sasmal and P. Jampana).
- "Optimization of
low-dose tomography via binary sensing matrices, " In Proc. of 17th IWCIA, ISI
9448, 337-351, Lecture Notes in Computer Science] (with T. Prasad, P.
Kumar and P. Jampana).
- "Reliable Low-Cost
Telecardiology: High-Sensitivity Detection of Ventricular Beats using
Dictionaries, " In Proc.
16th IEEE Healthcom, Natal, Brazil, 2014.," (with B. Chandra
and S. Jana)
- "Multivariable polynomials
for the construction of binary sensing matrices," In Proc. of CMCGS, Singapore,
February 2014 (with R. Naidu and P.V.Jampana)
Hurst exponent based anomaly detection in compressively sampled ECG
Signals," In Proc. of 15th IEEE HealthCom, Lisbon,
Portugal, 2013 (with S. Chandra and S. Jana)
from divergent ray projections," In Proc. of SPIE Imaging, San Francisco, USA, 2012, (with
- "Rotation invariant
simultaneous clustering and dictionary learning for image
retrieval," In Proc. of
IEEE-ICASSP, Kyoto, Japan, 2012 (with Y.Chen, V.Patel, J. Philips,
of ECG signals using multiscale approach," In Proc. of IEEE-SPCOM, 2012, IISc Bangalore, (with K.S.
Veena, P.Gupta, M. Amarnath)
- ‘’Compressed sensing for
reconstruction of reflectance spectra from tristimulus values, In
IEEE-Vcon Proceedings, 2010, (with M. Ravindranath).
- “Detection of edges in CT images
directly projection data,” In Proceedings
of Advances in Recent Technologies in Communication and Computing 2009, (with Amit Mishra and
- “Application of l1-norm
minimization technique to image retrieval,” Conference Proceedings in I. J. of Electronics and Communication
Engg, Vol. 3, No. 8, 1646-1649, 2009 (with S. Jain and A. Mishra).
- “Regularization of
incompletely, irregularly and randomly sampled data,” In 6th IEEE-ICVGIP Proceedings,
Bhubaneswar, December, 2008.
- “Signal reconstruction
from incomplete and misplaced measurements,” In Proc. of 69th EAGE, London, 2007, (with G. Hennenfent,
F. J. Herrmann)
- “Application of wavelets
in network security,” in “Enhancing
computer security with smart technology,” pp: 209-228, CRC
Press, 2005 (with S. Rawat)
- “Network intrusion
detection using wavelet analysis,” Lecture
Notes in Computer Science, 3356, pp: 224-232, Springer, 2004 (with
- Local image
reconstruction from localized projections via multiresolution approach,
In Combinatorial and Computational
(with P. C. Das).
- “Impact of windowing on
wavelet based reconstruction in tomograpgy,” Proc. of EMB-Int. Conf. on Biomedical Engineering, IISc,
Bangalore, 2001 (with P.C. Das)