PROJEK INDIVIDUASAS AUDIO VIDEO DALAM MULTIMEDIA

(DDZ2533)

BAB 5.0 UNDERSTANDING DIGITAL VIDEO TECHNOLOGY

ERNIE YUSNIZA BINTI AB MAJID900721-03-5742

10 FEBRUARY 2010

KOLEJ TEKNOLOGI DARULNAIMJLN PDG GOLF, PENGKALAN CHEPA

KELANTAN DARULNAIM.

1- The Digital Age

The world as we know it is changing, it’s going to digital.

The Digital Video Disc We can rent a movie on DVD This is new a storage medium that will hold

gigabyte of information on a single disc.

It’s enough space to include an entire feature-

length film with superior picture and sound. This is the latest series of advances in digital

video technology.

2- Digital Video (dv)

On your TV, you can surf the internet, or use a computerized DVR to record hours and hours of programming without videotape.

Video has evolved into digital video, DV. Video cameras use CCD’s (Charge-coupled devices), which are

computer chips that convert the optical images into electrical

impulses. Traditional video – use an analog signal. Digital video converts the analog signal into binary form, which

is represented by a series of zeroes and ones.

Digital Video

Digital Video Charge Coupled

3 – HISTORY OF DIGITAL VIDEO

Digital video technology explode in the 1990s. In 1970s, for special effects frames of analog video were converted

into :• Digital film • Altered

Digital Video Effect systems : Were pass through devices and the frames were not actually stored in memory.

Early 1980s, Digital Still Store devices were capable of storing and recalling individual video frames.

Mid 1980s, digital disc recorder were able playback and record images at the same time.

Digital

Video Effect

4 - Linear & Nonlinear Editing

4.1 Linear Editing Traditional video editing is called linear editing. The video program is edited consecutively from beginning to end. Is nonconsecutive in nature. Differences between linear and nonlinear editing :

It can be clearly illustrated by using the analog of an audio cassette tape (linear) and an audio compact disc, CD (nonlinear).

Cassette Tape Compact Disc

(linear) (nonlinear)

4.2 Nonlinear Editing Avid technology was the company that pioneered the digital video, or

nonlinear editing system. This new style of editing video on the computer in the professional

arena. It was known as desktop video when it original in the consumer

realm. As computer technology continued to evolved, the gap between

nonlinear editing and desktop video began to decrease. The term digital video was coined.

5 - Advantages of digital video It is commonly called today. Has several distinct advantages over linear editing. It’s faster, changes are easier to make. Editors have more creative freedom in arranging their shots. Easily change the editing order of their shots to see which

arrangement they like best. It does not suffer from generation loss because the video signal is

digital.

6 - THE VIDEO SIGNAL AND STANDARD

6.1 Video Signal :

1. Chrominance – the color portion of the video signal.

2. Luminance - the black-and-white portion of the video signal. Primary color – RGB (red, green, blue). Hue – the actual shade of color being displayed

while the saturation refers to the intensity of the color.

RGB Color: Luminance Color:

The video signal

Consumer Prosumer Professional

Composite S-Video Component

1 Cable 1 Cable 4 Cable

Chrominance and luminance are

blended

Chrominance and luminance kept

separate

Chrominance (3)Red

GreenBlue

Luminance (1)

VIDEO CABLE

S-VIDEO CABLE

6.2 The NTSC Video Signal

Video Signal that broadcast in the United States must adhere to a set of standards that was forth by NTSC.

NTSC – video standard requires that the video signal be broadcast at 525 horizontal lines of resolution and at 30 (29.97) frames per second.

Video images is produce on the TV screen by scanning these lines of resolution in two separate passes – each pass is referred to as a field.

Interlaced video - combine of two fields to form a frame. exp : TV. Non interlaced – exp : computer monitor.

7 – FILE SIZE IN DIGITAL VIDEO

Every pixel in a frame of digital video, contains information. Standard – 660 x 480 frame = 300,000 pixels. Compared the size of word processing document, digital video files

are enormous. Three primary factors in digital video :

1. Resolution

2. Frame rate

3. Color depth Resolution - size of video frame (measured in pixel). Frame rate – amount of frame that display in one second

(measured in frame per second). Color depth – number of color represent in video images

(measured in bit).

8 – video standard for broadcast, multimedia & internet

8.1 Broadcast Resolution :-

Analog video camera = 640 x 480 pixel. Digital video camera = 720 x 480 pixel. Full screen video. HDTV 2 resolution = 1280 x 720 pixel (progressive) or

1920 x 1080 pixel (interlaced). Frame rate = digital video 30(29.97) fps Full motion video Color depth = 32 bits Broadcast quality audio is either 48kHz (digital) or 44kHz (analog)

16 bit stereo.

8.2 Multimedia

Multimedia are more flexible than they are for broadcast. Depend upon the configuration of the computer. Computer with faster processor, faster CD-ROM drives and a lot of

RAM will play larger digital video files more smoothly than slower systems.

Resolution = 320 x 240 pixel (analog) or 360 x 260 pixel (digital). Frame rate = 15 fps. Color depth = 16 bits, but sometimes increased to 24 bits Audio = 48kHz or 32kHz (digital) or 44kHz or 22kHz (analog)

16 bits stereo .

8.3 Internet

Two basic methods for transmitting video over the internet :-

1. Can make digital video available as a downloadable movie – a copy of the entire digital video could be downloaded to the users computer.

o Advantage – the user would have a copy of the digital video movie, remain on the users computer.

2. Stream the video over the internet – video streaming temporarily loads the video into the users computer, frame by frame, either it plays.

o The movie cannot be replayed or saved.

Resolution – 160 x 120 pixels (analog) or 180 x 120 pixels (digital). Frame rate – seldom more that 10 fps. Color depth – usually 8 bit color. Audio – 11kHz, 8 bit mono, but could also be 22kHz (analog) or

32kHz (digital), 16 bit stereo or higher (if audio quality is a priority).