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Old 04-01-2008   #10
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Join Date: Jan 2008
Location: Fort Worth, TX
Posts: 161
Default Re: Blu-ray Resolution

In standard broadcast television, with interlaced video, there are two fields that make up each frame - each of these fields contain HALF the image. If first field contains all odd scan lines, then the second field contains all the even lines. The FIELD rate is 60 per second, but the FRAME rate is half that or 30 per second.

To convert interlaced video to progressive video, the two field portions are combined so that the screen is painted in a single pass. I suspect this is done by buffering the field information until enough of the data is in to begin painting the screen, timed such that last data will be available before the last of the image is to be painted, and paint it again with the same data while the new frame data come in, so that flicker is not observed. Processing could be performed on the second pass though, based upon a "history" of the data from preceding passes to either accelerate the next screen draw, or to improve its quality in some manner. If the source was truly progressive, then it could potentially contain new data on each pass.

The "pulldown" mechanism for movies works pretty much as you described for legacy content. I am unsure about what happens for new all-digital content though, since it may have no legacy compatibility requirements.
- Kloneman --
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