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I have noticed mostly on the small tv we watch from about 12" away (although I can see it in my large TV up close) that all dark/black background in films have a 'staticy' pattern in them....it's not really noticeable on normal tv programs that I can tell.


Is there some kind of video circuitry causing this or is it normal?


Sort of looks like different types of colors in a faint pattern like this"

.-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-'

.-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-'

.-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-'

.-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-' .-'


best I can do :)


These are hooked up via satellite into satellite box, RF to VCR, RF split to both TV's. The larger set uses S Video from the reciever though.


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You are seeing A/D sampling errors and video compression artifacts. There are less "relative" video samples in the lower voltage level (black) portions of the signal, which makes the digital noise more apparent.


Most video encoders only employ 8 or 10 bit sampling. If the sampling rate were increased, the A/D conversion process would have less errors, but would take up more bandwidth due to more data being created. In that case, the compression artifacts would be even more severe and begin to cause problems in the whites as well. (similar to the brief pixelation that occurs during QUICK motion scenes, etc.)


Sadly, DTV is all about compromises...
 
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