The greatest DTV detail level currently available is 1080i, which is a 1920x1080 interlaced widescreen format. Interlacing is done to reduce the image bandwidth to one-half of full-frame quality, which gives better frame update speed for quick-changing scenes such as sports, but at the same time reduces the overall image quality and introduces image flickering and "crawling scanlines" because of the alternating field refresh.
Full-frame progressive-scan 1920x1080 (1080p) requires up to twice the data bandwidth currently available in the DTV channel specification. 1080p may become an option in the future, as image compression algorithms improve, allowing more detail to be sent via the same channel bandwidth allocations to be used now.
The limitations of interlacing can be partially overcome through the use of advanced image processors in the consumer display device, such as the use of Faroudja DCDi and using internal framebuffers to eliminate scanline crawling.
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