DirecTV LSS-3200A Satellite TV System User Manual


 
10
Signal Format Analog
Digital
SD/ED HD
2-2. TV Signal Formats
The digital TV standards allow several different formats. Broadcasters can choose between
four formats:
480p - The picture is 704 x 480 pixels, sent at 60 complete frames per second (480i is
also possible, sent at 60 interlaced frames per second).
720p - The picture is 1280 x 720 pixels, sent at 60 complete frames per second.
1080i - The picture is 1920 x 1080 pixels, sent at 60 interlaced frames per second (30
complete frames per second).
(The p and i designations stand for progressive and interlaced. In a progressive for-
mat, the full picture updates every sixtieth of a second. In an interlaced format, half of the pic-
ture updates every sixtieth of a second.)
The 480i format is called SD. 480p format is called the ED format. 480i is roughly equivalent to
a normal analog TV picture. The 720p and 1080i formats are called the HD formats.
Some analog televisions can display a picture 720 pixels wide by 480 pixels high, thats a total
of 345,600 pixels. HD digital signals can have a maximum resolution of 1920 x 1080, thats
2,073,600 pixels, or six times more pixels than the older resolution. Pictures will be crisper and
cleaner, with more detail in every close-up and every panorama.
Standard Comparison Table
Active Lines 480 480 720 or 1080
Sound Stereo (2 ch)
Dolby Digital
®
(5.1 ch) Dolby Digital (5.1 ch)
MPEG Audio (2 ch)
Aspect Ratio 4 : 3 4 : 3 or 16 : 9 16 : 9
Resolution 720 x 480
640 x 480 1280 x 720
704 x 480 1920 x 1080