2D Matrix Data

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2D Matrix Data
2D Matrix Data
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Two-dimensional data has two location indicators
for each data point
If the location indicators are evenly spaced, the
data can easily be stored as a 2D Matrix file.
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Two-dimensional data has two location indicators
for each data point
X Y speed 0.5 0.5 0.0350 0.5 1.0 0.0714 0.5
1.5 0.3853 1.0 0.5 0.4911 1.0 1.0 0.2422 1.0
1.5 0.9207 1.5 0.5 0.5744 1.5 1.0 0.3305 1.
5 1.5 0.8485
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Two-dimensional data has two location indicators
for each data point
X
0.5 1.0 1.5 0.5 0.0350 0.0714 0.3853
1.0 0.4911 0.2422 0.9207 1.5 0.5744 0.3305 0.84
85
Y
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Organization of 2D Matrix files
There is no standard layout for 2D matrix files
Some standard file formats which use binary
storage of data HDF netCDF FITS TIFF
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Images as 2D Matrix files
The most common form of 2D matrix file is the
digital image.

• Remember that the pixel values or intensities in
  an image may represent
• intensity
• density
• temperature
• pressure
• some other measurement taken on a
• regular grid.

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Common Enhancement Techniques for Images
- look up table transformations - histogram
modifications - geometric transformations -
filtering
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Identity Transformation
TRANSFORMATION FUNCTION
transformed pixel value
original pixel value
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Photographic Negatives
TRANSFORMATION FUNCTION
transformed pixel value
original pixel value
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Photographic Negatives
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Thresholding
TRANSFORMATION FUNCTION
transformed pixel value
original pixel value
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Thresholding
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Contrast Stretching
TRANSFORMATION FUNCTION
transformed pixel value
LO
HI
original pixel value
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Contrast Stretching
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Grey level Distribution plotted as a Histogram
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Grey level Distribution plotted as a Histogram
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Grey level Distribution plotted as a Histogram
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