IT 380 A+: EXAM 2 ENGAGING THE LATEST UPDATE OF
QUESTIONS AND ANSWERS.
Reasons for using video; additional requirements
-Video is an excellent tool for delivering multimedia.
- Video places the highest performance demands on a computer and its memory and
storage
How does video work?
-Light reflected from an object through the
camera's lens is converted into an electronic signal by a charge-coupled device (CCD).
- This electronic signal contains three
channels of color information (RGB) and
synchronization pulses (sync).
-Several video standards exist that deal with the amount of separation between the
components of the signal.
How does Analog recording work?
- Video is recorded onto magnetic tapes
- Helical scan: head is tilted at an angle
- Each stripe is a video frame; interlaced.
- Audio is recorded in straight-line track at top
- Tracking provides fine adjustment and alignment
helical scanning
head is tilted at an angle
Issues with different display standards
- Multiple HDTV formats exist.
- Resolutions and frame rates vary
o NTSC
o PAL
o SECAM
o ATSC
Other display issues/techniques
, Overscan: image or video is cut off by the screen's physical frame
Underscan: image or video is not big enough for the screen so is surrounded by a black
boarder.
safe title area: the image will not be affected by overscanning, even in the worst
condition.
Interlacing vs progressive scanning
Interlacing - process of building a single frame from two fields that helps to prevent
flicker on CRT screens.
Interlacing is used to provide good visual quality with a narrow bandwidth.
Horizontal scan lines of interlaced frame are numbered consecutively and divided into
two fields: odd and even
Odd scan lines are displayed first, followed by even scan lines
Half of screen is updated with each refresh
Progressive - draw the lines of an entire frame in a single pass, without interlacing them
and without flicker.
Each refresh updates the entire screen
Each line is drawn sequentially
de-interlacing- Used to convert interlaced to progressive. Not same quality as pure
progressive
Interlacing
Is used to provide good visual quality with a narrow bandwidth
Progressive-scan
QUESTIONS AND ANSWERS.
Reasons for using video; additional requirements
-Video is an excellent tool for delivering multimedia.
- Video places the highest performance demands on a computer and its memory and
storage
How does video work?
-Light reflected from an object through the
camera's lens is converted into an electronic signal by a charge-coupled device (CCD).
- This electronic signal contains three
channels of color information (RGB) and
synchronization pulses (sync).
-Several video standards exist that deal with the amount of separation between the
components of the signal.
How does Analog recording work?
- Video is recorded onto magnetic tapes
- Helical scan: head is tilted at an angle
- Each stripe is a video frame; interlaced.
- Audio is recorded in straight-line track at top
- Tracking provides fine adjustment and alignment
helical scanning
head is tilted at an angle
Issues with different display standards
- Multiple HDTV formats exist.
- Resolutions and frame rates vary
o NTSC
o PAL
o SECAM
o ATSC
Other display issues/techniques
, Overscan: image or video is cut off by the screen's physical frame
Underscan: image or video is not big enough for the screen so is surrounded by a black
boarder.
safe title area: the image will not be affected by overscanning, even in the worst
condition.
Interlacing vs progressive scanning
Interlacing - process of building a single frame from two fields that helps to prevent
flicker on CRT screens.
Interlacing is used to provide good visual quality with a narrow bandwidth.
Horizontal scan lines of interlaced frame are numbered consecutively and divided into
two fields: odd and even
Odd scan lines are displayed first, followed by even scan lines
Half of screen is updated with each refresh
Progressive - draw the lines of an entire frame in a single pass, without interlacing them
and without flicker.
Each refresh updates the entire screen
Each line is drawn sequentially
de-interlacing- Used to convert interlaced to progressive. Not same quality as pure
progressive
Interlacing
Is used to provide good visual quality with a narrow bandwidth
Progressive-scan
