Tv Signal Formats - DirecTV LSS-3200A Owner's Manual

2-2. TV Signal Formats

Standard Comparison Table
Signal Format
Active Lines
Sound
Aspect Ratio
Resolution
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, that's a total
of 345,600 pixels. HD digital signals can have a maximum resolution of 1920 x 1080, that's
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.
Analog
SD/ED
480
Dolby Digital
Stereo (2 ch)
MPEG Audio (2 ch)
4 : 3 4 : 3 or 16 : 9
640 x 480
720 x 480
704 x 480
Digital
HD
480 720 or 1080
® (5.1 ch) Dolby Digital (5.1 ch)
16 : 9
1280 x 720
1920 x 1080
10