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2. TV
DVD Internet
VCD Streaming VDO
VDO on- Chat
demand
e-Learning
Mobile
It’s everywhere!!!
Phone
Cinema
...and Many
MORE...

3. Agenda
VDO Digital VDO
Fundamental Production
Record
Properties of Edit
VDO
Digital VDO Capture
Formats

4. Properties of VDO

5. Analog VDO
• Motion VDO was originally created and
stored in analog form.

6. Digital VDO
• A means of reproducing the continuous VDO
waveform as a stream of digital numbers.
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Interlacing embrace the
explanation!!
• Interlacing was originally conceived as a way to
achieve good visual quality within a limitations
of a narrow bandwidth.
odd field even field

8. Progressive Scanning
(non-interlaced scanning)
• A method of representing
moving images on a display
screen, in which every pixel is
represented in each frame.
• Computer monitors use a progressive scan.
• The standard refresh rate for a flicker-free
display is a vertical scan rate of 75 Hz or higher.
• It’s used to project movies in theaters.

9. Note
in digital TV terminology:
interlaced scan is denoted
by a lowercase i
progressive scan is
denoted by a lowercase p
frame rate: (60i, 24p)
resolution: (1080i, 720p)

10. Frame Rate
• Frame frequency is a measure of how quickly
an image device can produce unique
consecutive images called frames.
(expressed in frames per second - fps)
• Typically, the human eye can interpret motion at
10 fps, but this rate causes a flicker effect that’s
distract.
• Increasing the frame rate reduces flickering.

11. Frame Rate
• Movies - 14 fps
• Television:
• NTSC - 29.97 fps
• HDTV - 60 fps
• VDO games (frame rate is very important):
• action-oriented games - 20-30 fps
• 3D-heavy games - 90-100 fps

12. Aspect Ratios
• The ratio of the width of the image to its
height (w:h)
• motion-picture - 1.85:1 and 2.35:1
• tv screens - 1.33:1 (aka 4:3)
• HDTV - 1.78:1 (aka 16:9)
16:9 4:3 letterbox

13. Compression
• VDO is huge - one sec of analog VDO stored
in an uncompressed digital format takes up 1
MB of disk space
• thus, 5-min VDO ~ 300 MB
• not practical
• VDO compression is a MUST
• VDO contains many spatial and temporal
redundancies
• Codecs are needed for creating and viewing

14. VDO Compression
• Spatial compression (intra-frame)
• Temporal compression (inter-frame)
• Video compression is a tradeoff between disk
space, video quality, and the cost of hardware
required to decompress the video in a
reasonable time.

15. Spatial Compression
• Just image compression applied to a sequence
of images.

16. Temporal Compression
• Make key frames, say every 6 frames and do the
spatial compression on these frames.
• Between key frames, each one of them will be
replaced by a difference frame.

17. ที่มา: http://www.trustedreviews.com/camcorders/review/2007/12/22/The-Codec-Primer-Part-1/p1

18. Digital VDO File Formats

19. AVI
• Most common AV data on Windows
• Can be saved in a variety of compression
schemes - full frames (uncompressed), Radius’s
Cinepak, Intel Video, and Indeo.

20. MOV
• Quicktime Movie was developed by Apple
Computer
• MPEG-4
• Qt 7 (and later) use H.264

21. MPG
• The compressed VDO file format for standard
DVD using the MPEG-2 encoding standard
• A large file can be transferred to MPEG with
little loss of quality while dropping the bit rate
a great deal

22. • The MPEG group develops the standards for
encoding VDO and audio
• MPEG standards:
• MPEG-1: used as VCD standard (MP3 is the
popular compression)
• MPEG-2: use in many things such as DVD,
digital satellite TV and so on
• MPEG-4: support 3D content, low bit-rate
encoding, support for Digital Right
Management

23. Others
• WMV
• a part of Windows Media framework
• used for streaming VDO over the internet
• uses MPEG-4 standard
• RM
• a multimedia container with RealVideo and
RealAudio codecs in a single file
• is used to stream AV over the internet

24. VDO Production

25. Equipments
• Digital tapeless (D)
• HDV (D)
• DV (formerly DVC)
• 8mm (A)
• VHS (A)

26. Connecting Recorder to
Computer

27. Analog Camcorder

28. Coaxial
• VDO and audio signals are both carries in one
cable
• Poorest transfer

29. A/V
• Use RCA connectors
• Yellow is (composite) video
• Red is right audio & White is left audio

30. S-Video
• Separate video - transmit VDO
signals over a cable by dividing
the VDO info into 2 separate
signals: color (chrominance)
and brightness (luminance)
• Sharper than composite VDO
• must be used in conjunction
with audio cables

31. Digital Camcorder

32. USB
• USB 2.0 are common
• 480 Mbps

33. FireWire
• Developed by Apple
Computer
• IEEE-1394 standard
• 400 Mbps
• higher transfer rates are
available (800, 1600, and
up to 3100 Mbps)

34. Transferring from
Recorder to Computer
• Calculate disk space (uncompressed):
• (pixel width) x (pixel height) x (color bit
depth) x (fps) x (duration in secs) / 8,000,000
• say, 3-min VDO @ 15 fps, 24-bit depth,
320x240 pixels will take:
• (320) x (240) x (24) x (15) x (180) /
8,000,000 = 622 MB

35. VDO Editing
• Editing:
• cut and paste sections
• add special effects
• add transitions
• add titles