Assignment

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Kingdom of Saudi Arabia ةيدوعسلا ةيبرعلا ةكلمملا Ministry of Education ميلعتلا ةرازو

Umm AlQura University مأ ةعماج

ىرقلا

Adham University College مضأب ةيعماجلا ةيلكلا

Computer Science Department للآا بساحلا مسق

First Semester of 2018-1439/1440H Academic Year

Assignment

-Solutions-

Last Delivery Date: Monday, 07 / 11 / 2018 – 29 / 02 / 1440 H

Question One:

3 Marks

Choose the best answer:

1.Which one of the following is considered to be a prototyping tool that can be used in the design phase of a multimedia project.

a) Sketch

b) Photoshop c) Final Cut Pro d) a and b

2.The size of the 210 × 530 8-bit color image requires...of storage.

a) 0.1 MB b) 111 KB c) a and b d) 111300

KB

3.If Dr.Maryam is preparing a presentation for one of her lectures, she have chosen the color (253, 73, 141) for the text, what’s the prefect background color for her presentation based on the

complementary principle?

a) (2, 182, 114) b) (252, 72, 140) c) (254, 74, 142) d) None of the above

Multimedia Systems Course, 6803316-3

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Question Two: 1 Mark (1 Optional)

True/ False, with the correction of false statements.

1.If the Sampling Frequency is 1.5 times the True Frequency, then the Alias Frequency would be 3 times the True Frequency. ( False )

Alias Frequency would be half of the True Frequency which means it would be 0.5 times the True Frequency.

2.The more compression is done on a JPEG image the less quality factor Q the image will have. ( True )

Question Three: 2 Marks

Explain why we need to be able to have less than 24-bit color and why this makes for a problem.

Generally, what do we need to do to adaptively transform 24-bit color values to 8-bit ones?

Answer of Question Three:

May not be able to handle such large file sizes or not have 24-bit displays.

The colors will be somewhat wrong, however.

We need to cluster color pixels so as to best use the bits available to be as accurate as possible for the colors in an image. In more detail: variance minimization quantization–vmquant.m Minimum variance quantization allocates more of the available colormap entries to colors that appear frequently in the input image and allocates fewer entries to colors that appear infrequently. Therefore if there are for example many reds, as in a red apple, there will be more resolution in the red part of the color cube. An excellent implementation of this idea is Wu’s Color Quantizer (see Graphics Gems vol. II, pp. 126-133).

Question Four:

1 Mark

Match the color-related terms in the first column with characteristics in the second column.

First Column Second Column

A

wavelength

^C

luminance

B

color level

A

hue

C

brightness

^D

saturation

D

whiteness

B

chrominance

Question Five: 1 Mark

We don’t see flicker on a workstation screen when displaying video at NTSC frame rate.

Why do you think this might be?

Answer of Question Five:

NTSC video is displayed at 30 frames per sec, so flicker is possibly present. Nonetheless, when video is displayed on a workstation screen the video buffer is read and then rendered on the screen at a much higher rate, typically the refresh rate — 60 to 90 Hz — so no flicker is perceived. (And in fact most display systems have double buffers, completely removing flicker: since main memory is much faster than video memory, keep a copy of the screen in main memory and then when we this buffer update is complete, the whole buffer is copied to the video buffer.)

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Question Six:

(1 Mark Optional)

How many numbers of bits needed to be used to compress the word “EDUCATION” using Huffman algorithm?

Answer of Question Six:

P8:(9)

0 1

E:(1) P7:(8) 0 1

D:(1) P6:(7) 0 1

U:(1) P5:(6) 0 1

C:(1) P4:(5) 0 1

A:(1) P3:(4) 0 1

T:(1) P2:(3) 0 1

I:(1) P1:(2) 0 1 O:(1) N:(1)

The number of bits used:

E D U C A T I O N

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 8 = 44 bits.

Remember, “Success is 1% inspiration and 99% perspiration”😉 If you have any questions, feel free to ask me through my email

T.Mariah Sami Ahmed Khayat Teacher Assistant @ Adam University College

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