Video Standards

1
Video Standards

• NTSC - The Old Standard
• Digitized Video - On The Way
• MPEG - The New Standard
• Applications

2
NTSC - The Old Standard

• 1940/41 FCC forms NTSC(National Television
  System Committee)
• Field/frame rate 60/30 Hz (PAL 50/25)
• Lines 525 interlaced (7x52x3) ? 15.750 kHz
• Interlacing bandwidth/flicker/resolution
• Synchronization by H/V sync pulses
• Video bandwidth 4.2 MHz in 6 MHz channels
• Sound FM _at_ 4.5 MHz (2000/7 line rate)

3
Adding Color to NTSC

• Color encoding added to NTSC in 1953
• Separation of Luma Y and Color
• Color coded on subcarrier _at_ 455/2 line rate
• Line rate adjusted by 1001/1000
• Sound at 286 x line rate
• Drop frame time code
• Insufficient separation
• Dot crawl
• Hanging dots
• ...

4
Color Theory for Video

• Gamma
• Video operates in perceptional uniform space
• Graphics (should) operate in linear light space
• Luma not Luminance
• Y ? Y (from CIE)
• Color space YUV?
• RGB, RGB needs primaries and white point
• Y B-Y R-Y ITU Rec. 601 or Rec. 709 color
  space
• YPBPR normalized to -.5, .5
• YCBCR smaller excursion, head room
• YUV, YIQ NTSC only

5
Digitized Video

• 4fSC
• Sampling rate 14.318 MHz ( 4x subcarrier freq.)
• Samples 910 s/l, 768 s/al
• Easy reconstruction of color
• Everything is sampled
• Requires accurate phase control
• Perfect copies - used in studio
• D-2 tape standard
• No processing of video
• Different for NTSC, PAL, etc

6
Digitized Video

• ITU-R 601-4 (601)
• Sampling frequency 13.5 MHz
• Common multiple of NTSC/PAL line rate (6x 2.5
  MHz)
• Samples
• NTSC 864 s/l 720 s/al 525 l
• PAL 858 s/l 720 s/al 625 l
• YCBCR Color Space
• Color subsampling 422
• 10bit standard (8bit mode)
• Ancillary data in H/V blanking intervals
• Interface
• Parallel (SMPTE 125M)
• Serial (SDI, SMPTE 259M, 75O coax, 270 MHz)

7
Video Tape Formats

• Video tape made todays TV possible
• Non-simultaneous transmission of events
• Formats
• D1 3/4, component, 422, 10bit, R. 601, Sony
• D2 3/4, composite, 4fSC, 8bit, Sony
• D3 1/2, composite, 4fSC, 8bit, Panasonic
• D5 1/2, component, 422, 10bit, Panasonic
• D6 HDTV on D1 tape, 1.2Gb/s, 8bit, Y_at_76MHz
• DV, DVCAM digit., 411, 8bit, 51 DV, 25 Mb/s
• DVPRO-50 digit., 422, 8bit, 3.31 DV, 50 Mb/s
• Betacam SX digit., 422, 8bit, 101,
  Studio-MPEG-2
• Dig. Betacam digit., 422, 10bit, 21

8
Use of Digital Video

• Applications
• CD-I and Video-CD MPEG-1 on CD with App.
• DVD up to 17GB at UDF-filesystem, wide screen, multiple tracks, AC3
  and AAC surround audio, multiple languages, area
  codes, copy protection,
• ATSC/FCC Digital TV
• DSS/DBV 30 Mb/s, MPEG-2 ML_at_MP, 544_at_480, NTSC
  feed to Satellite with real-time MPEG encoder
• DVB(EBU) MPEG-2, Cable, etc.
• Video on Demand MPEG-2 on ATM Networks
• HDTV