1
Different Video Properties
 Video Standards
 Different countries use different video
standards for broadcasting
Video standard
Countries
PAL
The United Kingdom, most
countries in Europe, Hong
Kong, China, Singapore,
Australia
NTSC
The United States, Japan,
Taiwan
SECAM
France, Russia
TV display standards in different countries
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Different Video Properties
 Frames
 Digitized video consists of a number of
frames
 Slightly different frames are displayed
successively at high speed → continuous
motion
Frame 1
Frame 9
Frame 2
Frame 3
Frame 4
Frame 5
Frame 6
Frame 7
Frame 8
Frame 10 Frame 11 Frame 12 Frame 13 Frame 14 Frame 15 Frame 16
A video actually consists of individual frames
1
Different Video Properties
 Frame Size
 The width and height of individual frames
 Larger frame size → higher video quality →
larger file size
Frame size
Aspect ratio
Application
720 × 576
5:4
PAL DVD
480 × 576
5:6
PAL SVCD
352 × 288
11 : 9
PAL VCD
240 × 180
4:3
Web video
160 × 120
4:3
Web video or video
mail
Common video frame sizes
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Different Video Properties
 Frame Rate
 The number of video frames displayed on
the screen in one second
 Measured in frames per second (fps)
 Higher frame rate (above 24 fps) →
smoother motion
Frame rate (fps)
Multimedia system
30
NTSC TV
25
PAL TV
24
Movie films
15
Computer video or animation
(such as Flash movies)
12
Some common video frame rates and corresponding
multimedia systems
1
Different Video Properties
 Codec (Compressor and
Decompressor)
 The software used to compress and
decompress video files
 Compression reduces the storage space and
the video access time
Original
video
Compressed
video
Compression
Decompression
Storage
This step requires the
appropriate codec installed
on user’s computer
Decompressed
video
(playback)
1
Different Video Properties
 Codec
 Different codecs use different methods to
compress video
 Some common codecs
 MPEG-1, MPEG-2, MPEG-4
 Windows Media Video (WMV)
 DivX
2 Capture Digital Video
 Concept
 To capture digital video, it is necessary to
have
A capturing device (a camcorder)
A storage medium
Video encoding hardware and software
Video encoding
hardware and
software
Video capturing
device
Storage
medium
2 Capture Digital Video
 Examples
 Video capturing devices
DV camcorder
Digital camera
Webcam
 Video encoding hardware / Software
Video capture card
May use USB connection to the computer
and encoded by a software
2 Capture Digital Video
 Examples
A video capture card (top left) and an external video capturing
device (bottom left). VideoStudio, the video capturing and editing
software (right).
3 Common Video File Formats
 Audio Video Interleave (AVI)
 Windows video format developed by
Microsoft
 Large file size in uncompressed format
AVI (MPEG-4 codec)
File size: 3.28 MB
AVI (Cinepak Codec by
Radius)
File size: 13.1 MB
AVI (uncompressed)
File size: 111 MB
The same 15-second AVI video in 3 formats
3 Common Video File Formats
 Motion Picture Experts Group
(MPEG, MPG)
 A compression file format
 Preserves video quality yet supports high
compression ratio
3 Common Video File Formats
 Motion Picture Experts Group
(MPEG, MPG)
 A family of compression standards
Standard
Maximum
resolution
Application
MPEG-1
(1992)
352 × 288 (PAL) Video CDs, interactive
352 × 240 (NTSC) CD-ROMs and MPEG-1
MP3 music
MPEG-2
(1994)
720 × 576 (PAL) DVDs and digital TV
720 × 480 (NTSC) broadcast
MPEG-4
(1998)
-
Video in digital camera
mobile phone and iPod
 MPEG-4 can be as good as MPEG-2, but an
MPEG-4 video is of a smaller file size
3 Common Video File Formats
 Windows Media Video (WMV, ASF)
 A streaming compressed video format
developed by Microsoft
 Can be played by Windows Media Player
Windows Media Player
3 Common Video File Formats
 RealVideo (RV, RM)
 A compressed streaming audio format
developed by RealNetworks
 Can be played by RealPlayer
3 Common Video File Formats
 QuickTime (MOV)
 A streaming compressed multimedia file
format on Macintosh computers
 Can be played with QuickTime Player
QuickTime Player
4 Simple Video Editing
 Editing Movies
 Common video editing skills include
Adding titles
and
background
music
Applying
video filters
Applying
transition
effects
between video
clips