1
Q
What is a Sound Wave?
A
- Energy propagating through a medium
- Energy is nothing but vibrations of the particles in the medium
- A sound wave creates compressions and rarefactions in the medium
2
Q
Characteristics of Sound Wave:
A
- Frequency
- Wavelength
- Amplitude
- Speed
3
Q
Applications of audio in computer:
A
- Entertainment & multimedia
- Communication
- Education
- Music production
- Security
4
Q
Digital Audio file formats:
A
- MP3 (MPEG Audio Layer III)
- WAV (Waveform Audio file format)
- FLAC (Free Lossless Audio Codec)
- AIFF (Audio Interchange File Format)
- VOC (Creative Voice File)
5
Q
What is MP3?
A
- Lossy compression
- storing and transmitting audio like music
- Comparatively smaller audio size
- File size and audio quality are balanced
6
Q
What is WAV?
A
- Uncompressed
- Hence it retains original audio data
- File size is large as no compression technique used
7
Q
What is FLAC?
A
- Lossless compression
- as ‘Free’ -> an open source audio file format
- file size reduced without losing audio quality
- used for digital music distribution
8
Q
What is AIFF?
A
- Uncompressed and developed by Apple
- used to store high quality sound generally on PC
- File size larger as no compression
- for professional audio applications
9
Q
What is VOC?
A
- supports the use of compression technique like ADPCM
- used for speech and sound effects
- ADPCM compresses to reduce file size while maintaining audio quality
- used to store mono as well as stereo sound types
10
Q
What is Audio compression?
A
- Process of reducing the size of the audio file by removing or reducing the redundant or irrelevant data
- Goal is to reduce the file size while maintaining the quality
11
Q
Audio compression techniques:
A
- Delta modulation(DM)
- Adaptive Differential PCM (ADPCM)
- MPEG (Motion Picture Expert Group)
12
Q
What is video signal?
A
- an electronic signal that holds the video information like the images and motion, to be displayed on the screen.
- transmitted by video cameras, recorders and computer graphics devices
- via wires or wireless transmission.
13
Q
What are the video signal formats?
A
- Component Video
- Composite Video
- S - Video (Super Video)
- Analog Video
14
Q
What is Component Video?
A
- store and transmit 3 component signals
- simplest form is the collection of R,G and B
- cameras and other devices use three different connectors or wires to transmit
- RGB converted to YCbCr if same set of colors for color monitor as well as B/W
15
Q
What is Composite Video?
A
- transmits single signal over just one wire
- reduces cable/channel requirements
- luminance-chrominance format used for transmission
- Bandwidth split and allocated to luminance and chrominance
- Luminance has more bandwidth than chrominance
- transmitted via single RCA jack
- signals within the single wire interfere with each other
16
Q
What is S-Video?
A
- an analog signal format
- transmits luminance and chrominance portions over different wires
- improves picture quality as compared to composite video
- more expensive
- uses a 4 pin mini-DIN connector
17
Q
What is Analog Video?
A
- info as a continuous flow of analog data
18
Q
Enhanced Definition Television Standard(EDTV):
A
- refers to the resolution 480p
- enhancement to SDTV
- vertical and horizontal resolutions improved
- uses 4:3 aspect ratio for std. TV and 16:9 for widescreen
- 30 frames per sec
19
Q
Consultative Committee for International Radio communication(CCIR):
A
- historically related to analog TV systems
- has 2 options: NTSC and PAL
- max bandwidth for each TV channel 6MHz
- Aspect ratio -> 4:3
- Frame rate is 25fps
20
Q
A
