1. Which of the following is a receptor in the retina of the human eye?
a) Rods
b) Cones
c) Rods and Cones
d) Neither Rods nor Cones
Answer: c
Rods are long slender receptors while cones are shorter and thicker receptors.
2. How is image formation in the eye differ from that in a photographic camera
a) No difference
b) Variable focal length
c) Varying distance between lens and imaging plane
d) Fixed focal length
Answer: b
Fibers in the ciliary body vary the shape of the lens thereby varying its focal length.
3. Range of light intensity levels to which the human eye can adapt (in Log of Intensity-mL)
a) 10-6 to 10-4
b) 104 to 106
c) 10-6 to 104
d) 10-5 to 105
Answer: c
The range of light intensity to which the human eye can adapt is enormous and about the order 1010 from 10-6 to 104.
4. What is subjective brightness?
a) Related to intensity
b) Related to the brightness
c) Related to image perception
d) Related to image formation
Answer: a
Subjective brightness means intensity as preserved by the human visual system. Brightness adaptation means the human visual system can operate only from scotopic to glare limit. It cannot operate over the range simultaneously. It accomplishes this large variation by changes in its overall intensity.
5. What is brightness adaptation?
a) Changing the eye’s overall sensitivity
b) Changing the eye’s imaging ability
c) Adjusting the focal length
d) Transition from scotopic to photopic vision
Answer: a
The human eye has a wide dynamic range by changing the eye’s overall sensitivity and this is called brightness adaptation.
Brightness adaptation means the human visual system can operate only from scotopic to glare limit. It cannot operate over the range simultaneously. It accomplishes this large variation by changes in its overall intensity.
6. The innermost membrane of the human eye is
a) Blind Spot
b) Sclera
c) Choroid
d) Retina
Answer: d
The retina is the innermost membrane of the human eye. This is the layer of nerve cells lining the back of the eye. The retina has a layer of photoreceptor cells that helps in processing light.
7. What is the function of Iris?
a) Source of nutrition
b) Detect color
c) Varies focal length
d) Control the amount of light
Answer: d
Iris is responsible for controlling the amount of light that enters the human eye. The iris allows more light into the eye (enlarging or dilating the pupil) when the environment is dark and allows less light into the eye (shrinking or constricting the pupil) when the environment is bright.
8. ________ serve a general, overall picture of the field of view.
a) Cones
b) Rods
c) Retina
d) All of the Mentioned
Answer: b
Rods produce an overall picture of the field of view. Rod cells function as specialized neurons that convert visual stimuli in the form of photons (particles of light) into chemical and electrical stimuli that can be processed by the central nervous system.
9. Ratio of number of rods to the number of cones is _______
a) 1:20
b) 1:2
c) 1:1
d) 1:5
Answer: a
The ratio of the number of rods to the number of cones is 1:20.
No of rods: 6 to 7 million, No of rods: 75 to 150.
10. The absence of receptors is in the retinal area called _____________
a) Lens
b) Ciliary body
c) Blindspot
d) Fovea
Answer: c
The absence of receptors is in the retinal area called Blindspot.
Except for the blind spot, receptors are radially distributed. In the optic disk, there are no receptor cells. Axons of the retinal ganglion cells gather at the optic disk and form the optic nerve, which carries the neural signal into the brain. Because there are no receptors at the site of the optic disk, this location is also called the blind spot.
11. In 4-neighbors of a pixel p, how far are each neighbor located from p?
a) one pixel apart
b) four pixels apart
c) alternating pixels
d) none of the Mentioned
Answer: a
Each pixel is a unit distance apart from the pixel p.
12. If S is a subset of pixels, pixels p and q are said to be ____________ if there exists a path between them consisting of pixels entirely in S.
a) continuous
b) ambiguous
c) connected
d) none of the Mentioned
Answer: c
If S is a subset of pixels, Pixels p and q are said to be connected if there exists a path between them consisting of pixels entirely in S.
13. If R is a subset of pixels, we call R a _________ of the image if R is a connected set.
a) Disjoint
b) Region
c) Closed
d) Adjacent
Answer: b
If R is a subset of pixels, R is called a Region of the image if R is a connected set. A region in an image is a group of connected pixels with similar properties. Regions are important for the interpretation of an image because they may correspond to objects in a scene.
14. Two regions are said to be ___________ if their union forms a connected set.
a) Adjacent
b) Disjoint
c) Closed
d) None of the Mentioned
Answer: a
Two regions are said to be Adjacent to each other if their union forms a connected set.
or
Two regions are said to be adjacent if their union forms connected set boundaries region image
15. If an image contains K disjoint regions, what does the union of all the regions represent?
a) Background
b) Foreground
c) Outer Border
d) Inner Border
Answer: b
The union of all regions is called Foreground and its complement is called the Background.
16. For a region R, the set of points that are adjacent to the complement of R is called ________
a) Boundary
b) Border
c) Contour
d) All of the Mentioned
Answer: d
For a region R, the set of points that are adjacent to the complement of R is called boundary, border, and contour.
The words boundary, border, and contour mean the same set.
17. The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r centered at (x,y) is called :
a) Euclidean distance
b) City-Block distance
c) Chessboard distance
d) None of the Mentioned
Answer: a
The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r centered at (x,y) is called Euclidean distance.
Euclidean distance is measured using a radius from a defined center.
18. The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r, form a diamond centered at (x,y) is called :
a) Euclidean distance
b) Chessboard distance
c) City-Block distance
d) None of the Mentioned
Answer: c
The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r, form a diamond centered at (x,y) is called City-Block distance.
The formation of a diamond is measured as City-Block distance.
19. The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r, form a square centered at (x,y) is called :
a) Euclidean distance
b) Chessboard distance
c) City-Block distance
d) None of the Mentioned
Answer: b
The distance between pixels p and q, the pixels have a distance less than or equal to some value of radius r, form a square centered at (x,y) is called Chessboard distance.
20. Which of the following is NOT a type of Adjacency?
a) 4-Adjacency
b) 8-Adjacency
c) m-Adjacency
d) None of the Mentioned
Answer: d
We consider three types of adjacency:
a) 4-adjacency: Two pixels p and q with values from V are 4-adjacent if q is in the set N4(p).
b) 8-adjacency: Two pixels p and q with values from V are 8-adjacent if q is in the set N8(p).
c) m-adjacency(mixed adjacency): Two pixels p and q with values from V are m-adjacent if
q is in N4(p), or
2) q is in ND(p) and the set N4(p)∩N4(q) has no pixels whose values are from V.
