High Definition Television

2 Overview Technology advancements History Why HDTV? Current TV standards HDTV specifications Timeline Application Current status Hardware requirement Conclusion

3 Technological Advancements Video Home System (VCR) & Video CD 330×480 (250 lines) Digital Versatile Discs (DVD) 9GB /210 Mbps | 720×480 (520 lines) NTSC / 720×576 (576 lines) PAL Blu-Ray (HD) 150GB / 432 Mbps | 920×1080 (1080 lines) / 1280×720 (720 lines) NTSC / PAL 30fps / 25fps High Definition Television (HDTV) progressive / interlaced

4 VHS DVD BluRay

5 History 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 countries already run HDTV broadcasts.

6 Why HDTV? Higher-resolution picture Wider picture Digital surround sound Additional data Easy to interface with computers

7 Current TV Standards NTSC: National Television Systems Committee PAL: Phase Alternation Line SECAM: Séquential Couleur Avec Mèmoire

8 Progressive vs. Interlaced 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

9 HDTVSDTV

10 HDTV Specs 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 HDTV Revisited 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 Revisited 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

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