Every Pixel - Processing Data

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Detailed Description

Once the ground stations receive data from Landsat, there's still a lot of processing to make every pixel usable. Here's an overview of some of that work.
 

Details

Date Taken:

Length: 00:01:34

Location Taken: Sioux Falls, SD, US

Transcript

The data received by ground
stations from Landsat looks

very different from what
users download.

First, the data is received
in 1 gigabyte chunks that

are recombined to form the
long swaths of the

satellite’s path. Odd and
even Sensor Chip Assemblies

send offset and
overlapping strips.

Gain and bias adjustments
correct for differences

between assemblies, as well
as each individual detector

based on calibration data.
Each band is also brought

back into alignment and
the data is rotated to

prepare for placement
in its final scene.

From here, ancillary data
detailing the position and

orientation of Landsat 8 is
calculated with elevation

data about the ground.
This model traces each

pixel in the final scene
back to a 4 by 4 block

of pixels from the raw
data. Those 16 values are

weighted to produce a
final radiometrically

and geometrically
accurate pixel.

Finally, a library of
Ground Control Points

are compared to points
in the scene to evaluate

how accurately the pixels
align. This measurement

is the scene’s RMSE value,
the number of meters an

average pixel is off.
Landsat’s best quality

scenes, “tier 1”, are
within 12 meters, about

a third of a pixel.

meet this mark.