720p

This chart shows the most common display resolutions, 720p being one of the 16:9 formats shown in blue.

720p (720 lines progressive) is a progressive HD signal format with 720 horizontal lines/1280 columns and an aspect ratio (AR) of 16:9, normally known as widescreen HD (1.78:1). All major HD broadcasting standards (such as SMPTE 292M) include a 720p format, which has a resolution of 1280×720p.

The number 720 stands for the 720 horizontal scan lines of image display resolution (also known as 720 pixels of vertical resolution).[1] The p stands for progressive scan, i.e. non-interlaced. When broadcast at 60[note 1] frames per second, 720p features the highest temporal resolution possible under the ATSC and DVB standards. The term assumes a widescreen aspect ratio of 16:9, thus implying a resolution of 1280×720 px (0.9 megapixels).

720i (720 lines interlaced) is an erroneous term found in numerous sources and publications. Typically, it is a typographical error in which the author is referring to the 720p HDTV format. However, in some cases it is incorrectly presented as an actual alternative format to 720p.[3] No proposed or existing broadcast standard permits 720 interlaced lines in a video frame at any frame rate.[4]

Comparison with interlace scanning

Progressive scanning reduces the need to prevent flicker by anti-aliasing single high contrast horizontal lines.[5][6] It is also easier to perform high-quality 50<->60 Hz conversion and slow-motion clips with progressive video.

S Resolution A/R
HD 960×720p 4:3
HD 1280×720p 16:9
HD 720×1280p 9:16

S=standard A/R=aspect ratio[7]

Notes

  1. ^ It is, however, more commonly broadcast at (60/1.001), or precisely 59.940059, matching the NTSC SDTV field rate; this and the 50.00 Hz of PAL are still the second and third highest standard framerates.[2]

See also

References

  1. ^ "720p – AfterDawn: Glossary of technology terms & acronyms".
  2. ^ Hoffner, Randy (2008-01-09). "Will the End of NTSC Be the End of 59.94?". TVTechnology. Retrieved 2010-10-08.
  3. ^ Briere, Daniel; Patrick Hurley (2006). HDTV for Dummies. For Dummies. p. 13. ISBN 9780470096734.
  4. ^ "ATSC Standard: Video System Characteristics of AVC in the ATSC Digital Television System" (PDF). 2008-07-29. Archived from the original (PDF) on 2012-10-04. Retrieved 2011-07-24.
  5. ^ "720p". AfterDawn. 2010-08-10. Retrieved 2010-10-08.
  6. ^ "720p". CNET Glossary. Archived from the original on 2010-09-30. Retrieved 2010-10-08.
  7. ^ encyclopedia of photography