5.4 Histogram
This menu groups operations for finding and transforming
image histograms. nip2 represents histograms and
lookup tables as images with Type set to Histogram.
Histograms may have pixels in any format and any number
of bands. You can only find histograms of unsigned 8- and
16-bit images.
-
New Histogram
- This makes a new ramp histogram.
A set of sliders let you adjust the shape. Use Map
Histogram to apply your ramp to an image.
-
Build LUT from Scatter
- Make a histogram
from a set of (x,y) values.
-
Tag Image as Histogram
- Mark an image as
actually being a histogram after all.
-
Find Histogram
- A one dimensional histogram
treats each band as an independent variable. An
n-dimensional histogram treats each pixel as a
vector of n elements, where n is the number of
bands in the image.
-
Map Histogram
- Looks up each pixel in the input
in the histogram and send the found value to the
output.
-
Equalise Histogram
- Find the global or locally
histogram equalised image.
-
Cumulative Histogram
- Use this and friends to
calculate a cumulative histogram, normalise a
histogram and match two histograms.
-
Find Profile
- Searches from the edges of an image
for the first non-zero pixel and returns a profile
histogram.
-
Find Projections
- Sum columns and rows.
-
Plot Slice
- Mark a guide on an image (drag from
the image rulers, or click File / New / Guide)
and click Plot Slice to make a histogram
which is a horizontal or vertical slice through an
image. Use Extract Arrow to extract the area
around an arrow or guide. Use Plot Object to
make a plot of any object.