Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

ch3 > CH5G > Flashcards

CH5G Flashcards

1
Q

What is a pixel?

A

A pixel is a point that has no dimension, area, or visibility but can have a coordinate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is a pixel a box or a disk?

A

No, it is a point.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the main side effects of scan conversion?

A

Unequal intensity, overstrike, and aliasing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What causes unequal intensity in raster displays?

A

The human perception of light based on density and intensity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why do diagonal lines appear dimmer than horizontal or vertical lines?

A

Due to lower pixel density along diagonals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the solution to unequal intensity in diagonal lines?

A

Increase the number of pixels used.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is overstrike?

A

When the same pixel is written more than once, intensifying its brightness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How to prevent overstrike?

A

Check if a pixel has already been written before writing it again.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is aliasing?

A

A jagged appearance of curves or diagonal lines due to low screen resolution.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the visual effect of aliasing on a screen?

A

Jagged edges on diagonal or curved lines.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the goal of anti-aliasing?

A

To smooth edges and reduce jaggedness in digital images.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the two general approaches to anti-aliasing?

A

Super-sampling and area sampling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is super-sampling?

A

Sampling at a higher resolution and filtering down to display size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is another term for super-sampling?

A

Post-filtering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is area sampling?

A

Sampling using boxes or other shapes that simulate area coverage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is another term for area sampling?

A

Pre-filtering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does area sampling require?

A

Primitives with area, like lines with width.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does super-sampling reduce aliasing?

A

By taking multiple samples per pixel and averaging them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What type of anti-aliasing is most common in hardware?

A

Super-sampling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does multisampling relate to anti-aliasing?

A

It’s a form of super-sampling used in GPUs like GeForce3.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is done in multisampling?

A

Multiple subpixel samples determine pixel intensity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is a pixel treated in area sampling?

A

As a square with a measurable area.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is unweighted area sampling?

A

All covered pixel areas contribute equally to intensity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is weighted area sampling?

A

Contribution varies depending on the location within the pixel.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is W(x,y) in weighted area sampling?
A weighting function based on position.
26
Where are higher weights given in weighted sampling?
Toward the center of the pixel.
27
What is a filter function?
A function applied to calculate weighted average intensity across a pixel.
28
What does the filter function integrate?
The weighted contribution over the pixel surface.
29
What are three common filter types?
Box, cone, and Gaussian.
30
What is the Box filter?
Equal weights for all surrounding pixels.
31
What does zero padding do in filtering?
Adds extra zero pixels to accommodate filtering at edges.
32
What is convolution in filtering?
The process of combining the filter with the pixel values.
33
What is the Cone filter?
Uses linear decreasing weights with distance.
34
What is the Gaussian filter?
Uses exponential/logarithmic weight decrease with distance.
35
What is the purpose of the weighting function Ws?
To scale the maximum intensity Imax.
36
What is the formula for intensity using Ws?
I = Imax • Ws
37
How are pixel contributions determined in unweighted area sampling?
By the proportion of the pixel area covered by the primitive.
38
Are all parts of the pixel considered equally in unweighted area sampling?
Yes.
39
What shape is usually assumed for pixels in area sampling?
Square.
40
What is the benefit of unweighted area sampling?
Simplicity and ease of implementation.
41
What does 'primitive' refer to in sampling?
A basic graphical element like a line or shape.
42
In unweighted area sampling, what is the result when half of a pixel is covered?
The pixel is displayed with 50% of the full intensity.
43
Can unweighted sampling still produce aliasing artifacts?
Yes, though reduced compared to no anti-aliasing.
44
What is the goal of weighted area sampling?
To give more importance to the center of the pixel during intensity calculation.
45
How does position affect weights in weighted sampling?
The closer to the center, the higher the weight.
46
What does the weighting function W(x,y) determine?
The contribution of a primitive passing through pixel position (x,y).
47
Why is weighted sampling more accurate?
It models human visual sensitivity better by focusing on pixel centers.
48
What is the trade-off of weighted sampling?
Higher computational cost.
49
How are weights assigned in the box filter?
Equally.
50
What is the shape of a box filter kernel?
Rectangular.
51
How many pixels are typically used in a simple box filter?
Three or more.
52
What is the formula representation of a box filter (example)?
[1 1 1]
53
Why use zero-padding in filtering?
To handle boundary conditions during convolution.
54
What is a pixel?
A pixel is a point that has no dimension, area, or visibility but can have a coordinate.
55
Is a pixel a box or a disk?
No, it is a point.
56
What are the main side effects of scan conversion?
Unequal intensity, overstrike, and aliasing.
57
What causes unequal intensity in raster displays?
The human perception of light based on density and intensity.
58
Why do diagonal lines appear dimmer than horizontal or vertical lines?
Due to lower pixel density along diagonals.
59
What is the solution to unequal intensity in diagonal lines?
Increase the number of pixels used.
60
What is overstrike?
When the same pixel is written more than once, intensifying its brightness.
61
How to prevent overstrike?
Check if a pixel has already been written before writing it again.
62
What is aliasing?
A jagged appearance of curves or diagonal lines due to low screen resolution.
63
What is the visual effect of aliasing on a screen?
Jagged edges on diagonal or curved lines.
64
What is the goal of anti-aliasing?
To smooth edges and reduce jaggedness in digital images.
65
What are the two general approaches to anti-aliasing?
Super-sampling and area sampling.
66
What is super-sampling?
Sampling at a higher resolution and filtering down to display size.
67
What is another term for super-sampling?
Post-filtering.
68
What is area sampling?
Sampling using boxes or other shapes that simulate area coverage.
69
What is another term for area sampling?
Pre-filtering.
70
What does area sampling require?
Primitives with area, like lines with width.
71
How does super-sampling reduce aliasing?
By taking multiple samples per pixel and averaging them.
72
What type of anti-aliasing is most common in hardware?
Super-sampling.
73
How does multisampling relate to anti-aliasing?
It’s a form of super-sampling used in GPUs like GeForce3.
74
What is done in multisampling?
Multiple subpixel samples determine pixel intensity.
75
How is a pixel treated in area sampling?
As a square with a measurable area.
76
What is unweighted area sampling?
All covered pixel areas contribute equally to intensity.
77
What is weighted area sampling?
Contribution varies depending on the location within the pixel.
78
What is W(x,y) in weighted area sampling?
A weighting function based on position.
79
Where are higher weights given in weighted sampling?
Toward the center of the pixel.
80
What is a filter function?
A function applied to calculate weighted average intensity across a pixel.
81
What does the filter function integrate?
The weighted contribution over the pixel surface.
82
What are three common filter types?
Box, cone, and Gaussian.
83
What is the Box filter?
Equal weights for all surrounding pixels.
84
What does zero padding do in filtering?
Adds extra zero pixels to accommodate filtering at edges.
85
What is convolution in filtering?
The process of combining the filter with the pixel values.
86
What is the Cone filter?
Uses linear decreasing weights with distance.
87
What is the Gaussian filter?
Uses exponential/logarithmic weight decrease with distance.
88
What is the purpose of the weighting function Ws?
To scale the maximum intensity Imax.
89
What is the formula for intensity using Ws?
I = Imax • Ws
90
How are pixel contributions determined in unweighted area sampling?
By the proportion of the pixel area covered by the primitive.
91
Are all parts of the pixel considered equally in unweighted area sampling?
Yes.
92
What shape is usually assumed for pixels in area sampling?
Square.
93
What is the benefit of unweighted area sampling?
Simplicity and ease of implementation.
94
What does 'primitive' refer to in sampling?
A basic graphical element like a line or shape.
95
In unweighted area sampling, what is the result when half of a pixel is covered?
The pixel is displayed with 50% of the full intensity.
96
Can unweighted sampling still produce aliasing artifacts?
Yes, though reduced compared to no anti-aliasing.
97
What is the goal of weighted area sampling?
To give more importance to the center of the pixel during intensity calculation.
98
How does position affect weights in weighted sampling?
The closer to the center, the higher the weight.
99
What does the weighting function W(x,y) determine?
The contribution of a primitive passing through pixel position (x,y).
100
Why is weighted sampling more accurate?
It models human visual sensitivity better by focusing on pixel centers.

ch3 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions