Full Screen Resolution?

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Can someone please tell me what is full screen resolution on a TV screen (when making VCD's).....is it 352 x 240 or 640 x 480? I am extremely confused as to what is the truth. The Dazzle says it is full screen but yet it only captures at 352 x 240. Plase help. Thanks

-- Cale Ferguson (5150@onramp.net), March 10, 2000


352x240 is the only possible dimension for a legal NTSC-VCD. And it's showed full screen in a TV. Analog media such as VHS is 320x480 (interlaced), DVD is 720x480 (interlaced also). All the 3 formats are seen full screen on the TV, so resolution actually doesn't care much (to the TV!) because the signals transmitted to it are already adapted by the player to fit the whole screen, no matter the resolution.

-- Matias (mpetrel@fi.uba.ar), March 11, 2000.

The normal analogue 4:3 NTSC is an effective 480 horizontal lines with an effective 640 samples per line in the width.

The 352 x 288 VCD is expanded in the process by, in layman's terms, doubling the number of lines and taking the 352 and turning them back into 640 samples, with some loss in detail in the process. You can use the same approach with Matias's other sizes except for the 720 wide DV format, in NTSC it only contains the 640 effective samples. In PAL the 720 contains the effective 768 samples.

In terms of stills we deal in pixels in both directions so a horizontal row of pixels becomes a line and each pixel in it a sample.

-- Ross McL (rmclennan@esc.net.au), March 12, 2000.

oopps read 352 x 240 NTSC for 352 x 288 PAL - sorry!

-- Ross McL (rmclennan@esc.net.au), March 12, 2000.

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