Linearment Mapping in Remote Sensing

Figure 1: Outcome of Linearment Mapping

Figure 2: DEM file

Question in regarding this topics:

Q1: what is grayscale image?

Greyscale image is image that consist of only 2 colour, black and white. But with different value, hue and chroma. Example of greyscale image in remote sensing is those panchromatic image with one band. Greyscale image must first generated in lineament mapping as it is best to be viewed and compare in grayscale.

Q2: What is false colour composite image

False composite colour image used in interpretation of the map which involve spectral reflectance signature. False colour composite image normally involve in using multi spectral image that are nearly infrared, red and or green spectral band. Different attribute of  colour represent different reflectance value.

Q3:which is the best colour composite for lineament mapping.

The convert of RGB to either intensity or hue or saturation. This is because it helps in preserving the original colour through high pass filtering.

Q4: What is the difference between .ers and .alg

.ers format	.alg format
Data file	Data set
Example: contour.ers,road .ers	Example: 1990.alg
Cannot be open with ermapper staright forward. Only can be used as data layer.	Finish work were saved in .alg form and open to continue editing using ermapper
When we finish editing the .alg were saved as .ers	Unfinish work were saved in .alg in order to continue. Multiple .ers can be used to create .alg

Q5: compare the two  imagery  and describe the landuse change that had occurred between 1990 and 2002.

It is obviously that colour between the map is different. For example, if green color represent the vegetation. It can be noticed that vegetation in 1990  is lighter than 2002. This can be due to regrowth or plantation of new vegetation at the site. The river in 2002 also show obvious lighter colour, we assume that the landuse of the site improved over the year.

Q6: Describe the difference noticed in terms  of spatial resolution..

In term of spatial resolution, by turning on the intensity, we see clearer image with darker colour.

Q7: which one is the best to digitize road? Polyline, polygon or rectangle?

Polyline. Polyline appear are used to digitize line whereas polygon and rectangle used to digitize shaped objects.

Q8: Describe the procedure of changing the colour and thickness of the polyline/

After the we digitize the polyline, line table appear, from there we change their properties.

Q9: what is DEM?

Digital elevation model. It is 3D representation and common input data for any terrain mapping and analysis. It is common in slope and aspect analysis. Contour line created represent the angle of declination of the slope.

Q10: What is the lowest and highest elevation in the study area?

The range is between 800m and 1800m.