Document for Meteorology Data
Written by: Jia Li, The Pennsylvania State University, June 2010
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Data creation:
The data file DBZ_DATA_CONDITIONED.mat was created by Dr. Fuqing Zhang's
Lab
in the Department of Meteorology at Penn State University. It contains
41
cloud images generated for weather forecasting.
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1. The data file is in matlab format. To load the data, use the
following
commands in Matlab:
load DBZ_DATA_CONDITIONED;
After loading the data, 41 arrays named DBZ_FT18_EF11 to DBZ_FT18_EF51
will
be created. The value of each array element indicates the intensity of
cloud
at the corresponding pixel location.
To view the array as an image by "xv", write out the data into an image
file
in pgm format. For example in Matlab:
dat=DBZ_FT18_EF11;
[row,col]=size(dat);
f1=fopen('image.pgm','w');
fprintf(f1,'P5 %d %d 255\n',col,row);
fwrite(f1, dat', 'uchar');
fclose(f1);
Then use "xv image.pgm" to view the image under OS command.
-------------------------------------------------------------------------2. These cloud images are used to test clustering algorithms that segment
an
image into clusters of clouds. The shapes of the cloud clusters which
tend
to be perceived by human vision are highly non-elliptical. This poses
difficulty to many widely used clustering algorithms such as k-means or
mixture-model-based clustering which implicitly assume Gaussian-type
clusters.