The source fault consists of the asperity and the remaining area is called the background area.
The noisy area at the borders of the image is called the background area.
The signal intensity in the background area is usually low.
It can be seen that most of the background areas are encoded with inter coding without redundant version, because these areas are relatively static, and with the temporal replacement concealment algorithm, losing these areas will not lead to huge distortion.
The parts that we want to discard from the final result would show very low values given by those two equations, because most of the nodes in those sub-meshes would be residing over a background area.
Background area used for each species in the background similarity test.
Thus, the values for X and M were calculated in the following way: Value for X=SI (Xs)− SI (background) (area (Xs)/area (background)); Value for M=SI (M − SI (background) (area (M /area (background)).
Somerville and Dorchester contained both near-highway (<400 m) and urban background (>1000 m) areas; Chinatown (near-highway) and Malden (urban background) were paired because they have demographically similar populations and Chinatown was too small to contain a background area.
However, this assumption may cause halo artifacts around strong edges, because the background illumination is not always smooth and may change sharply in some areas.
That might be because the background conditions were not conducive.
