Section 4 Flashcards
What is a radiometric issue?
An issue involving the sensor
Random noise is the ________ noise of a sensor. This tends to be ______ in an image
Background, white
How do you remove background noise?
Take an image with the shutter closed, any values recorded you later subtract with the image
What is striping?
When the detectors on a sensor are not properly calibrated and as a result stripes will appear on the image.
In a MSS sensor how many detectors are there per band?
6
What are the methods for getting rid of striping called and how many are there?
Pass, 2
What is a drop line correction?
If a recorder fails there will be a missing line of data
What is a random bit error?
Errors on individual pixels. They are replaced by an average of the surrounding pixel or employing a median filter
What does atmospheric correction get rid of?
Different illumination effects and changes in atmospheric composition
What is a common reason for atmospheric disturbances?
Suspended particles in the atmosphere making an image hazy
Where will the most atmospheric distortions occur according to Rayleigh and Mie scattering?
Where the wavelengths will be shortest. Green and blue.
What two situations do you need to take into account bidirectional reflectance?
Data with high spacial resolution in respect to the object being scanned and data taken at different times of the year with changing sun angles
When scattering is increased with an increase in path radiance what happens?
Contrast decreases
Name four radiometric issues.
Instrument noise
Striping
Dropline
Bit errors
