mes per second. One of these methods is known as 'inverse 3:2 pull down.'
-There are fewer pixels in a Video CD image than on a standard videotape frame (D1, for instance), so the image must be reduced in size, or subsampled. The way this is done depends on a number of factors including the picture rate (film or video), broadcast standard (NTSC or PAL), and play-back system.
-The actual process of compressing data successfully is as much an art as it is a science. Years of experience and an aesthetic sense are required to make sure that all of the appropriate 'knobs' in the process are fine tuned. For the best results, it is extremely important to have the services of an experienced video post-production house or a person with extensive post-production experience. Using all of the techniques available, it is possible for a skilled video technician to optimize the results of the encoding process.
There are some basic rules of thumb for getting the best results from the encoding process in conjunction with MPEG:
-Stay as close to the original source as you can. Each additional (analog) generation degrades the quality. This is axiomatic.
-Component source is better than composite. Digital source is better than analog. Component versus composite is a more important factor in quality than is the digital versus analog factor. Thus, the order of preference among common formats is D1, Beta SP, D2, and then any other format. Avoid letting anyone talk you into using D2 instead of Beta SP (if the Beta system is a high quality component one.) Here's a summary chart:
Digital Analog
Component D1
Digital Betacam Beta SP
Composite D2 1', 3/4', VHS
-Garbage in╤worse compressed garbage out! Remember that VHS, Umatic, Beta, etc., are all forms of compression when the original medium was film. Compression magnifies any artifacts in the source; it doesn't conceal them. If you have a compressed intermed
