Class/Function Glossary

File Input/Output

Class/Function Description
AsterDatabase Create/Query a spectral database generated from the ASTER Spectral Library
aviris.open Open an AVIRIS image file
aviris.read_aviris_bands Read an AVIRIS band calibration file
envi.open Open a data file (image, classification, or spectral library) that has an ENVI header
envi.create_image Open a new (empty) image file with an ENVI header
envi.save_classification Save classification labels to a file with a corresponding ENVI header
envi.save_image Save image data to a file with a corresponding ENVI header
envi.SpectralLibrary Class to create/save spectral libraries in ENVI format
erdas.open Open an Erdas LAN image file
open_image Generic function for opening multiple hyperspectral image file formats

Display/Visualization

Class/Function Description
ColorScale Create color scales for use with data display functions
get_rgb Produce RGB array suitable for display from image data
ImageView Class for interacting with image displays (returned by imshow)
imshow Primary function for displaying raster views of image data (an extension of matplotlib’s imshow providing overlays and interactivity)
ppi Display Pixel Purity Index values while ppi function executes.
save_rgb Saves image data in common RGB image formats (e.g., JPEG, PNG)
view_cube View an interactive 3D image cube
view_nd Display an interactive N-D visualization of image pixel data

Dimensionality Reduction

Class/Function Description
linear_discriminant Computes Fisher’s Linear Discriminant for a set of classes
mnf Minimum Noise Fraction
ppi Calculates Pixel Purity Index (PPI)
principal_components Calculates principal components of an image

Target Detection

Class/Function Description
ace Adaptive Coherence/Cosine Estimator
matched_filter Applies a linear matched filter detector for a given target
msam Modified Spectral Angle Mapper (MSAM)
rx RX anomaly detector
spectral_angles Spectral Angle Mapper (SAM)

Classification

Class/Function Description
create_training_classes Creates a TrainingClassSet object from image data and ground truth
GaussianClassifier Gaussian Maximum Likelihood Classifier (GMLC)
kmeans Unsupervised image classification via k-means clustering
MahalanobisDistanceClassifier A classifier using Mahalanobis distance
map_class_ids Create a mapping between class labels in two classification images
map_classes Modifies class indices according to a class index mapping
msam Modified Spectral Angle Mapper (MSAM)
PerceptronClassifier A Multi-Layer Perceptron (MLP) Artificial Neural Network (ANN) classifier
spectral_angles Spectral Angle Mapper (SAM)
TrainingClassSet Object returned from spectral.create_training_classes (used by some classifiers)

Spectral Transforms

Class/Function Description
BandInfo Container for spectral band discretization/calibration data
BandResampler Class for performing band resampling
FisherLinearDiscriminant Object returned by linear_discriminant to transform image data into linear discriminant space.
LinearTransform A callable linear transform that can be applied to image data
MNFResult Object returned by mnf to reduce dimensionality via Minimum Noise Fraction (MNF)
ndvi Normalized Difference Vegetation Index (NDVI)
PrincipalComponents Object returned by principal_components. Transforms data into PCA space and - optionally - reduces dimensionality.

Math/Statistics

Class/Function Description
bdist Bhattacharyya distance
calc_stats Calculates Gaussian statistics for image data
covariance Calculates image data covariance
cov_avg Calculates covariance averaged over a set of ground truth classes
noise_from_diffs Estimate image noise statistics from a homogeneous region
orthogonalize Performs Gram-Schmidt orthogonalization on a set of vectors
principal_components Calculates principal components of an image
transform_image Applies a linear transform to image data

Miscellaneous

Class/Function Description
settings Object for controlling SPy configuration options
algorithms.algorithms.iterator Function returning an iterator over image pixels