Video Standards NTSC The Old Standard Digitized Video

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Video Standards • NTSC - The Old Standard • Digitized Video - On The

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

NTSC - The Old Standard • 1940/41: FCC forms NTSC (National Television System Committee)

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 (7 x 52 x 3) 15. 750 k. Hz • 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 NTSC • Color encoding added to NTSC in 1953 • Separation

Adding 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 Video • Gamma: • Video operates in perceptional uniform space •

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

Digitized Video • 4 f. SC: • • • Sampling rate 14. 318 MHz

Digitized Video • 4 f. SC: • • • Sampling rate 14. 318 MHz (= 4 x 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 Video • ITU-R 601 -4 (601): • Sampling frequency: 13. 5 MHz •

Digitized Video • ITU-R 601 -4 (601): • Sampling frequency: 13. 5 MHz • Common multiple of NTSC/PAL line rate (6 x 2. 5 MHz) • Samples: • NTSC: • PAL: • • • 864 s/l 720 s/al 525 l 858 s/l 720 s/al 625 l YCBCR Color Space Color subsampling 4: 2: 2 10 bit standard (8 bit mode) Ancillary data in H/V blanking intervals Interface: • Parallel (SMPTE 125 M) • Serial (SDI, SMPTE 259 M, 75Ω coax, 270 MHz)

Video Tape Formats • Video tape made today’s TV possible • Non-simultaneous transmission of

Video Tape Formats • Video tape made today’s TV possible • Non-simultaneous transmission of events • Formats: • • • D 1 3/4”, component, 4: 2: 2, 10 bit, R. 601, Sony D 2 3/4”, composite, 4 f. SC, 8 bit, Sony D 3 1/2”, composite, 4 f. SC, 8 bit, Panasonic D 5 1/2”, component, 4: 2: 2, 10 bit, Panasonic D 6 HDTV on D 1 tape, 1. 2 Gb/s, 8 bit, Y’@76 MHz DV, DVCAM digit. , 4: 1: 1, 8 bit, 5: 1 DV, 25 Mb/s DVPRO-50 digit. , 4: 2: 2, 8 bit, 3. 3: 1 DV, 50 Mb/s Betacam SX digit. , 4: 2: 2, 8 bit, 10: 1, Studio-MPEG-2 Dig. Betacam digit. , 4: 2: 2, 10 bit, 2: 1

Use of Digital Video • Applications: • CD-I and Video-CD: MPEG-1 on CD with

Use of Digital Video • Applications: • CD-I and Video-CD: MPEG-1 on CD with App. • DVD: up to 17 GB at <10 Mb/s, MPEG-2 streams on UDF-filesystem, wide screen, multiple tracks, AC 3 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