very satisfactory. 
Though the KLT processing yields good results, it involves 
considerable computational effort. On the other hand the KLT is an 
optimal transform under a variety of criteria and guarantees minimum 
MSE. Instead of the KLT, other suboptimal orthogonal transforns 
which have fast algorithms [8,14] for easy implementation can be 
used, Suboptimal transforms like the discrete cosine transform 
(DCT) [19], the C-matrix transform [20] (which is a close integer 
approximation to the DCT), the Walsh Hadamard transform can be used, 
The DCT approximates very closely the KLT for a Markov-I process, 
Such  suboptimal transforms have been widely used in image 
compression as a substitute for KLT to reduce the bit rate for 
transmission or storage. 
eference 
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digital image data", IEEE Trans. Geosc. and Remote Sens., 
vol.GE-22, pp.177-191, May 1984 
2 J.C. Price, "Comparison of the information content of data from 
the LANDSAT-4 Thematic Mapper and the Multispectral Scanner", IEEE 
Trans, Geosc. and Remote Sens., vol.GE-22, pp.272-280, May 1984 
3. Special Issue on LANDSAT-4, IEEE Trans. Geosc. and Remote 
Sens., vol.GE-22, May 1984, 
4, Special LIDQA issue, Photogrammetric Engg. & Remote Sensing, 
vol.LI, Sept.1985 
5. Bernstein et al, "Analysis and processing of LANDSAT-4 sensor 
data using advanced image processing techniques and technologies", 
IEEE Trans.  Geosc. and Remote Sens., vol.GE-22, pp.192-221, May 
1981. 
6. L.: Fusco, U. Frei and A. Hsu, "Thematic Mapper:Operational 
activities and sensor performance at ESA/Ethernet", Photogrammetric 
Engg. & Remote Sensing, vol.LI, pp. 1299-1314, Sept.1985 
7. H.C. Andrews, "Introduction to mathematical tecchniques in 
pattern recognition”, Wiley-Interscience, New York, NY, 1972 
8, D.F. i Elliott and ‘K.R. Rao, "Fast transforms: Algorithms, 
Analyses and Applications", Academic Press, New York, NY, 1982. 
9. A.K. Jain, "A sinusoidal family of unitary transforms", IEEE 
Trans, Pattern Analysis and Machine Intell.,  vol.PAMI-2, 
10. K.R. Rao, ed.,"Discrete transforms and their applications", 
Van Nostrand Reinhold Company, New York, NY, 1985 
268