Video StandardsVideo Standards

• NTSC - The Old Standard

• Digitized Video - On The Way

• MPEG - The New Standard

• Applications

NTSC - The Old StandardNTSC - 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 @ 4.5 MHz (=2000/7 line rate)

Adding Color to NTSCAdding Color to NTSC• Color encoding added to NTSC in 1953

• Separation of Luma Y’ and Color

• Color coded on subcarrier @ 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• ...

Color Theory for VideoColor 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, R’G’B’ needs primaries and white point• Y’ B’-Y’ R’-Y’ ITU Rec. 601 or Rec. 709 color space• Y’PBPR normalized to [-.5, .5]• Y’CBCR smaller excursion, head room• Y’UV, Y’IQ NTSC only

Digitized VideoDigitized 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

Digitized VideoDigitized 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/al525 l• PAL: 858 s/l 720 s/al625 l

• YCBCR Color Space• Color subsampling 4:2:2• 10bit standard (8bit mode)• Ancillary data in H/V blanking intervals• Interface:

• Parallel (SMPTE 125M)• Serial (SDI, SMPTE 259M, 75Ω coax, 270 MHz)

Video Tape FormatsVideo Tape Formats• Video tape made today’s TV possible

• Non-simultaneous transmission of events

• Formats:• D1 3/4”, component, 4:2:2, 10bit, R. 601, Sony• D2 3/4”, composite, 4fSC, 8bit, Sony• D3 1/2”, composite, 4fSC, 8bit, Panasonic• D5 1/2”, component, 4:2:2, 10bit, Panasonic• D6 HDTV on D1 tape, 1.2Gb/s, 8bit, Y’@76MHz• DV, DVCAM digit., 4:1:1, 8bit, 5:1 DV, 25 Mb/s• DVPRO-50 digit., 4:2:2, 8bit, 3.3:1 DV, 50 Mb/s• Betacam SX digit., 4:2:2, 8bit, 10:1, Studio-MPEG-2• Dig. Betacam digit., 4:2:2, 10bit, 2:1

Use of Digital VideoUse of Digital Video• Applications:

• CD-I and Video-CD: MPEG-1 on CD with App.• DVD: up to 17GB at <10Mb/s, MPEG-2 streams on

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@MP, 544@480,

NTSC feed to Satellite with real-time MPEG encoder• DVB(EBU): MPEG-2, <15 Mb/s, AAC, Satellite,

Cable, etc.• Video on Demand: MPEG-2 on ATM Networks• HDTV