Video integration squashes cost, artifacts

-- EDN, 12/7/2000

As the high-definition TV (HDTV) continues its frustratingly slow emergence, the interest in interim technologies that optimize the quality of today's video sources is on the rise. "HDTV-ready" televisions lack the necessary digital tuner and other circuitry but provide a direct-connection from an external decoder to their higher quality picture tubes. Until HDTV arrives, they take advantage of line-doubling, progressive-scan, and other enhancement technologies for lower resolution NTSC, DSS, DVD, Hi-8, S-VHS, and similar formats.

The name Faroudja is doubtlessly familiar to any of you who have dreamt of obtaining—or actually taken the plunge and purchased—a line doubler for use with a projection screen in a home-theater setting. Faroudja's no-holds-barred corporate edict produced image processors with outstanding quality. Unfortunately, the resultant cost kept the company's products out of the reaches of all but the video-lunatic fringe.

Faroudja is now a division of Sage, and the company's latest line doubler and deinterlacer, the $29 (10,000) FLI2200, is an impressive integration achievement (Picture). Sage squeezed all the circuitry previously housed in a five-device, 0.8-µm-fabricated chip set into one 0.25-µm-manufactured, 176-pin TQFP device. Sage claims that it took no technological short cuts to achieve this consolidation. In fact, the chip is more flexible than its predecessor, operating either in a low-cost, no-external-memory mode with a line-interpolation algorithm or in conjunction with 4 Mbytes of external-SDRAM frame buffer to implement the highest quality adaptive de-interlacing algorithm. You can also run the FLI2200 in either a 10-bit or a lower cost, 8-bit configuration.

Sage's stated goal with the FLI2200 is to deliver HDTV-like picture quality having no artifacts, cross-color, feathering, line flicker, or "jaggies," at affordable prices. Features include motion-adaptive cross-color suppression to remove NTSC and PAL color artifacts and per-pixel, motion-adaptive deinterlacing. Directional, co-relational deinterlacing with per-pixel selection of edge direction produces a smooth picture free of aliasing effects (see "Display technology's results are compelling, but legacy is un'clear,'" EDN, Oct 26, 2000, pg 63). The 3-to-2 and 2-to-2 frame-drop-down modes adjust for film- and video-derived material.

Applications for the FLI200 include inside the display itself (in conjunction with uncorrected video sources), inside a video source such as a progressive-scan DVD player (in conjunction with an HDTV-ready TV), or between the video sources and the destination display. FLI2200 interlaced input options include 8- or 10-bit D1 (CCIR656), 16- or 20-bit YUV (CCIR601), and 24- or 30-bit RGB or YCrCb. The chip supports both autodetected, 525-line, 60-Hz NTSC and 625-line, 50-Hz PAL and SECAM sources and as many as 1100 pixels per line. Progressive-scan output alternatives include 8-, 10-, 16-, and 20-bit YUV, and 24 or 30-bit RGB or YCrCb. The FLI2200 interfaces gluelessly to most standard video and MPEG DVD decoders, as well as to Sage's FLI2000 video decoder and FLI2220 luma/chroma enhancer and OSD generator.

Sage, 1-408-383-5300, www.sageinc.com.

—by Brian Dipert