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In: Wagner W., Szekely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010, IAPRS, Vol. XXXVIII, Part 7B
tuation: We
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. Our aim is
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I | Actions performed from first cycle and on.
Figure 1. Flow chart of the proposed generalized super
resolving approach.
EXPERIMENTAL VERIFICATION
In this section the authors present two types of experimental
results, both coming from airborne camera capturing urban
area. In Figures 2(a) and 2(b) we present two experimental
results. In both, the upper row contains from left to right: a high
resolution image, the same image taken at a quarter of the
resolution and the obtained reconstruction. The cross section is
seen in the lower row. Red corresponds to the reconstruction
image, green is the quarter resolution image, and blue is the half
resolution image used for comparison. The reconstructed image
obtained from the multiplexing of the high resolution image and
the quarter resolution image follows the cross section of the half
resolution image very well while having an improved contrast
by 16.7% in Figure 2(a) and by 12.3% in Figure 2(b). The
correlation between the reconstructed image and the HR image
is 98.2% and the mean square error is less than 0.8%, for the
later test case.
In the second experiment presented in Figure 3, we obtain the
photograph of the same scenery using two different
wavelengths. We assume that in the shorter wavelength image
we succeeded to obtain only the lower right quarter of the
image. By the same iterative procedure (but using different
parameters) we generate a new image (result) containing high
resolution data even outside the imposed data region. In the
lower row of Figure 3 one may see the reconstructed result
(left) and its cross section (right). An improvement of more than
10% in the contrast is obtained when comparing the
reconstruction results (red) and the original image at low
resolution (longer wavelength).
High resolution
Quarter
resolution
reconstructed
16.7% improvement in contrast Zoom of cross
Note that the
reconstruction follows
the half-resolution
image quite well (with
improved contrast)
especially when
compared to quarter
resolution image.
High resolution
Quarter
resolution
reconstructed
12.3% improvement in contrast Zoom of cross section
Again the reconstruction
follows the half-resolution
image quite well (with
improved contrast)
especially when
compared to quarter
resolution image.
Figure 2. Experimental results using airborne camera images,
(a). Captured image #1. (b). Captured image #2. In both cases,
the upper row contains from left to right: a high resolution
image, same image at quarter of resolution, and the
reconstruction results. The cross section is seen in the lower
row. Red is the reconstruction, green is the quarter resolution
image, and blue is the half resolution image used for
comparison. The reconstructed image obtained from
multiplexing of the high resolution image and quarter resolution
image follows the cross section of the half resolution image
very well while having an improved contrast (improvement by
16.7% in (a), and 12.3% in (b)).