TECHNICAL HIGHLIGHTS

LD100 TECHNICAL HIGHLIGHTS – The LD100 is far more than simply a “line doubler”. It is a truly unique product in the world of high performance video. The LD100 is actually a complex image processor that consists of three distinct components – all utilizing patented Faroudja technologies and engineered into one chassis; the SuperNTSC decoder , the Faroudja proprietary line doubler, and Faroudja’s innovative bandwidth expansion circuit that allows for the sharpening of image details. Line doubling by itself is simple and inexpensive to achieve. But simply doubling the lines of information is worse than doing nothing at all because the visual result is a picture of lesser quality. To achieve film-like quality, a great deal more is required than just doubling the lines. The block diagram below provides a sim- ple view of Faroudja’s multi-faceted solution for perfect pictures. The technical and visual benefits of each of these special circuits are explained more fully below.

SECTION A – The LD100 SuperNTSC Decoder: Elimi- nates COLOR BLURRING – The engineers of the 1940’s (and the 1950’s, before and during the development of color broadcasting), had no idea that video images would one day be blown up as large as they are today. They therefore designed the color section of the NTSC standard with severe bandwidth restrictions. This causes colors in various video images to “blur” and “smear”. These effects are further aggravated by storage media, such as VHS tapes, that further degrade the chroma or color signal. e.g.

– note how deep reds smear on VHS tape images.

The Faroudja LD100 utilizes proprietary circuitry to recre- ate and further correct color details. Technically, this is accomplished by making use of the sharper black and white transitions to develop a correction signal that is then used to sharpen the color transitions. The result is colors that are restored with sharp details and video images that retain their original crisp look.

RAINBOW PATTERNS – When you notice the fine detail of a striped referees shirt rippling with colored rainbows as the camera pans by, you’ve seen video cross-color inter- ference.

This annoying artifact is caused by imperfect separation of the color (chroma), and black and white (luminance) sig- nals by the color decoder circuitry. Simple techniques used commonly to separate the two signals can be effec- tive most of the time, but occasionally are fooled by finer pitch detail areas like the referees shirt. The decoder in the LD100 has patented digital adaptive comb filter cir- cuitry that eliminates decoding errors of this type and enables the reproduction of sharper, cleaner color images.

DOT CRAWL and HANGING DOTS – This phenomena is easily seen with large, highly colored, stationary graphics like titles and credits. Dot crawl is a rapid upwards move- ment of colored dots on sharp vertical transitions. Hanging dots lie underneath all the colored horizontal transitions. Both of these color aberrations are artifacts that appear due to an imperfect color decoding process. The LD100 has two separate and patented correction circuits that work to eliminate both of these distortions. The impact is color transitions that are clear, sharp and natural.

SECTION B – THE LD100 Patented Line Doubler: elimi- nates VISIBLE SCAN LINES – The secret of the LD100’s uncanny ability to double the lines of information without adding digital artifacts is in its unique ability to detect motion and interpolate correctly to “fill in the blank lines”. The Faroudja LD100 does this better than any other line doubler thanks to its proprietary, patented circuitry. It is the only line doubler in existence that can detect the dif- ference between a film image that has been transferred to video or video image that emanates from a video camera. After detecting the image type, the LD100 adjusts its algorithm to compensate accordingly.

This is critical because today’s home theaters are primarily used to show films that were transferred to video whether on tape, laserdisc or off the air (virtually all prime time pro- grams are film transferred to video). The inability of other line doublers to detect motion correctly is what causes most of them to be unwatchable due to digital artifacts. The LD100 offers sharper, uniquely clean, artifact-free film-like images without visible scanning lines.

Historically speaking again, electrical engineers back in the 1940’s knew the resolution of a picture tube depends

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Meridian Audio LD100/LD100U manual Technical Highlights