5. •Color Television Transmission breakthrough in 1940
GC Camarena of Mexico
•MPEG is born at NASA’s Video Pattern Recognition entre
MPEG has since been used for standardization of video formats.
•MPEG-1 standard provided the foundation for DTV
But was not popular due to popularity and wide acceptance of ATV
•DTV via DTH services took off in late 1990s
Popular ones in India are Zee’s DishTV and Tata’s TataSKY
•MPEG-2 standard finalized in ‘93 and implemented in 2004
18 countries already run HDTV broadcasts.
7. NTSC: National Television Systems Committee
PAL: Phase Alternation Line
SECAM: Séquential Couleur Avec Mèmoire
TV Standards NTSC PAL ATSC
Regions North Asia, Europe, World
America South America Standard
Channel Bandwidth 6MHz 8MHz 6MHz
Aspect ratio 4:3 4:3 16:9
8. •Progressive scan rewrites whole screen at one pass
Interlaced scan rewrites half the screen
•P-scan draws all the lines of moving pictures in a
sequence
Interlaced draws odd or even lines at a time
•Flickering is more common in interlaced display
But anti-aliasing and interpolation techniques have helped reduce
flickering
•Progressive scan has higher vertical res.
Consequently requires higher bandwidth for same no. of frames as interlaced
10. •System outlined in the ATSC standard is based on the
MPEG-2 Main Profile and MPEG-4 AVC Profile
•Video formats span the range of Main Level to High Level
•Audio Compression is based on the Dolby AC-3 system with
sampling rate 48kHz and perceptually coded
•5.1 Channels of surround-sound audio
•Transport subsystem based on MPEG-2 Transport Stream
•Packets consist of 188 bytes
•RF subsystem is 8 VSB
11. •System outlined in the ATSC standard is based on the
MPEG-2 Main Profile and MPEG-4 AVC Profile
•Video formats span the range of Main Level to High Level
•Audio Compression is based on the Dolby AC-3 system with
sampling rate 48kHz and perceptually coded
•5.1 Channels of surround-sound audio
•Transport subsystem based on MPEG-2 Transport Stream
•Packets consist of 188 bytes
•RF subsystem is 8 VSB
12. •HDTV image size of 1050 by 600 at 30 frames per sec, the
bandwidth required to carry that image quality using the
analog transmission system is 18MHz. However, it will
require more bandwidth to transmit it in digital format.
•With the MPEG-2 compression, the bit rate is compressed
from more than 1 Gbps to about 20 Mbps, which transmit
digitally only require bandwidth 6MHz