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Flash Ahhh · 12-13-2002, 06:01 AM

mgsooner,

A layer change happens because a disk isn't a single layer, it's dual layer. Different players handle layer changes differently.

Progressive scan has nothing to do with layer changes.

Progressive scan is a video component or signal that processes or displays every scan line of a video frame in sequence rather than cutting part of the scan lines out.

To better understand this, the opposite of a progressive scan is an interlaced scan. Interlaced scan takes a video component or signal and assigns (inserts) alternating scan lines in a video frame which helps reduce flicker without the transmission of extra video information.

Basically an interlaced scan is one that takes an image, and erases every other line and would have a black line in it's place. The video information is the same for every black line. So say you are watching an image with 480 lines of resolution. With the interlaced scan, you'd have 240 signals of actual video, and 240 signals of black lines, but only 241 of total lines had to be sent to the video display source since the black line is repeated. With the progresive scan, you'd get the full 480 lines of actual video image.

Why bother? Well, if you just sent 1/2 the video signal, the picture would be all choppy.

Hope that helps.

-Flash

12-13-2002, 06:01 AM	#2 (permalink)
Flash Ahhh Moderator Emeritus Well Worth the Double Dip! Join Date: Feb 2001 Location: 8.4 Miles from the newest Hooters Restaurant	mgsooner, A layer change happens because a disk isn't a single layer, it's dual layer. Different players handle layer changes differently. Progressive scan has nothing to do with layer changes. Progressive scan is a video component or signal that processes or displays every scan line of a video frame in sequence rather than cutting part of the scan lines out. To better understand this, the opposite of a progressive scan is an interlaced scan. Interlaced scan takes a video component or signal and assigns (inserts) alternating scan lines in a video frame which helps reduce flicker without the transmission of extra video information. Basically an interlaced scan is one that takes an image, and erases every other line and would have a black line in it's place. The video information is the same for every black line. So say you are watching an image with 480 lines of resolution. With the interlaced scan, you'd have 240 signals of actual video, and 240 signals of black lines, but only 241 of total lines had to be sent to the video display source since the black line is repeated. With the progresive scan, you'd get the full 480 lines of actual video image. Why bother? Well, if you just sent 1/2 the video signal, the picture would be all choppy. Hope that helps. -Flash __________________ Flash - Moderator Emeritus - Savior of the Universe Criterion (krî´tir´èæn) Greek [kritËreon], *Noun.* (circa 1622) - Definitiveness. Set standard. Principle, rule or test upon which value or decision can be based. Characterization in which all others are judged. Last edited by Flash Ahhh : 12-13-2002 at 06:08 AM.