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Have you ever observed digital compression artifacts in HD?
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Shane
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Have you ever observed digital compression artifacts in HD?
Have you ever observed digital compression artifacts such as macroblocking and mosquito noise when watching an HD program?
(This question is among a batch of questions that were asked at the DisplaySearch HDTV Conference 2005. For more information, you can click the logo below.)
(This question is among a batch of questions that were asked at the DisplaySearch HDTV Conference 2005. For more information, you can click the logo below.)
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gn2
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YES!
The biggest single downfall of HD broadcasts is the broadcasters who squeeze the bandwidth to the point where they introduce all kinds of MPEG artifacting. It is TERRIBLE. I have seen bitrates so low that ANY motion at all sets off the macroblocking.
I capped the new "Dr.Who" from HD cable, and the macroblocking from too low bitrate MPEG2 encoding is so bad they can't even broadcast the intro to the show without it cropping up. On still shots, it looks great, but ANY movement destroys the image.
I have a very old cap of "Gladiator" where the bitrate is almost 19Mbs, and the quality of the image, as a result, is phenomenal. It is almost like looking out a window at reality, instead of watching a movie.
I can't stress enough how important adequate MPEG encoding bitrates are. Without them, HD is not really HD.
The biggest single downfall of HD broadcasts is the broadcasters who squeeze the bandwidth to the point where they introduce all kinds of MPEG artifacting. It is TERRIBLE. I have seen bitrates so low that ANY motion at all sets off the macroblocking.
I capped the new "Dr.Who" from HD cable, and the macroblocking from too low bitrate MPEG2 encoding is so bad they can't even broadcast the intro to the show without it cropping up. On still shots, it looks great, but ANY movement destroys the image.
I have a very old cap of "Gladiator" where the bitrate is almost 19Mbs, and the quality of the image, as a result, is phenomenal. It is almost like looking out a window at reality, instead of watching a movie.
I can't stress enough how important adequate MPEG encoding bitrates are. Without them, HD is not really HD.
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raycar
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Follow-up Question
First off- what is mosquito noise?
Yes, I have definately seen motion artifacts due to compression. But occassionally I see what I call micro blocking unretlated to motion.
I get local HD channels from both OTA and Dish Network.
While an OTA channel can be perfect, the Sat picture sometimes goes in to spasms of micro, large, and picture freezes. Signal strength in the 80s.
Yes, I have definately seen motion artifacts due to compression. But occassionally I see what I call micro blocking unretlated to motion.
I get local HD channels from both OTA and Dish Network.
While an OTA channel can be perfect, the Sat picture sometimes goes in to spasms of micro, large, and picture freezes. Signal strength in the 80s.
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Richard
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Hi Ray,
Mosquito noise is the tiny little cloudy trash that appears around text and is the best example. The text is laid over the image and should not be changing anything in the image. Imagine taking a drawing, putting some fonts on it and then taking your pencil and scribbling all around the edges of the font into the image.
Mosquito noise is the tiny little cloudy trash that appears around text and is the best example. The text is laid over the image and should not be changing anything in the image. Imagine taking a drawing, putting some fonts on it and then taking your pencil and scribbling all around the edges of the font into the image.