TEST YOURSELF -VECTOR AND RASTER IMAGES

What is a coordinate value, a geographic identifier value, and an attribute value?

What are the five principal drawing objects?

What are nodes and vertices?

How would a triangular polygon drawing object be defined in 1) an IDRISI, 2) an ARC/INFO, vector image file?

What is the function of the .VAL file in the case of a vector image?

In what form is data stored in a raster image file?

Other than the attribute value of the pixel to be plotted, what other information must be supplied to enable the computer to draw a raster image? Where in IDRISI is that information stored?

What parameters are common to both vector and raster image files?

What is a palette file, and how does it relate to a) a vector file;b) a raster file?

How can you vary the attributes of a line?

A green line is drawn from coordinate postion 0, 0 to position 1,1. What would the file look like in a) vector format; b) raster format.

What does the term resolution mean with respect to raster images?

If you were use a palette of 256 colours to colour an image with only four classes of drawing objects, what difference would choosing autoscaling or not during display make to the colours exhibited in the image?

What is a document .DOC or .DVC file?

A raster image type may be ascii, binary, or packed binary. What do these terms mean?

Is it possible to have a packed binary type in the case of a vector image?

An image data type may be integer, real, or byte. What do these terms mean?

Is it possible to have a byte image data type in the case of a vector image?

An image needs to have defined a reference system and reference units? Discuss this.

Columns and rows in a raster related to Min-Max X and Y values by what parameter?

What do the Min-Max X-Y values determine (define, show) in a vector image?

Is it possible to display lines and polygons on the same layer in 1) Idrisi?; 2) Autocad?