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Old 11-09-2020, 01:01 PM
 
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When I watch my cable TV with HD, and there is an explosion or a lot of bright lights, I can see the image breaking into large pixels. I saw some articles saying it's because the signal isn't strong enough. It's the typical HD cable box and I was watching TNT HD.

I think it is more visible with explosions because large areas are the same color so you'll notice the blocking more. It doesn't happen when watching other things like Jeopardy or the news.

Would you expect this to happen when you watch cable TV? I think it doesn't happen when watching a Bluray or DVD. I haven't tried it.
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Old 11-09-2020, 01:47 PM
Status: "Enjoying the winter" (set 27 days ago)
 
Location: East of Seattle since 1992, originally from SF Bay Area
34,080 posts, read 61,975,311 times
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We had that problem with several local stations (Comcast box) about a year ago. I replaced the 8 year old cheap HDMI cable between the box and the TV with a higher quality one, and that solved it until a few weeks ago, when the problem returned. This time I noticed that the coax coming in from outside had a splitter on it before going into the cable box, but the other "out" connector had nothing on it. I took the splitter off and connected directly from the wall to the box, and problem solved.


Not to say that this is your problem, but things to check.
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Old 11-09-2020, 02:06 PM
 
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Sounds to me like compression on the video stream.

Things that are moving fast with a lot of action and color take up more bandwidth, so they are more visibly compressed to fit the available "pipe" for the channel.

It should not be a HDMI or other issue, as this seems like a source problem rather than at the TV. However, I'm aware of one type of compression artifact that is due to transmission errors (looks like ghost images) which could be due to something in-between.

https://www.howtogeek.com/428815/why...cture-quality/

"The problem is the extra bandwidth is only used to host more channels. While OTA TV places just one channel on each 6 MHz band, cable companies use aggressive compression algorithms (like MPEG-4) to shove around 20 channels on each 6 MHz band. As you’d expect, this aggressive compression leads to a dramatic loss in quality. It’s kind of like shoving 20 movies on a single DVD."

The fact that it doesn't seem to happen during slow moving/little changing shows tells me it's likely the provider.

You might find this interesting as well.

https://en.wikipedia.org/wiki/Compression_artifact
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Old 11-09-2020, 04:57 PM
 
19,703 posts, read 59,606,057 times
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Quote:
Originally Posted by markjames68 View Post
Sounds to me like compression on the video stream.

Things that are moving fast with a lot of action and color take up more bandwidth, so they are more visibly compressed to fit the available "pipe" for the channel.

It should not be a HDMI or other issue, as this seems like a source problem rather than at the TV. However, I'm aware of one type of compression artifact that is due to transmission errors (looks like ghost images) which could be due to something in-between.

https://www.howtogeek.com/428815/why...cture-quality/

"The problem is the extra bandwidth is only used to host more channels. While OTA TV places just one channel on each 6 MHz band, cable companies use aggressive compression algorithms (like MPEG-4) to shove around 20 channels on each 6 MHz band. As you’d expect, this aggressive compression leads to a dramatic loss in quality. It’s kind of like shoving 20 movies on a single DVD."

The fact that it doesn't seem to happen during slow moving/little changing shows tells me it's likely the provider.

You might find this interesting as well.

https://en.wikipedia.org/wiki/Compression_artifact
^^^ Bingo!

Digital HD can require a lot of data being pushed during certain scenes. The problem with providers trying to minimize bandwidth usage to add the "Portuguese puppy shopping channel" or some other questionable revenue stream is not new. Back at least twenty years ago I had a discussion with a CSR at the old DirectTV, because Turner Classic Movies, which are for the most part black and white and take up little bandwidth, were blocking and becoming unwatchable. DTV had reduced the allotted bandwidth over the satellite feed, in favor of better resolution for football games and the like. There was a minor improvement after that, but TCM lovers were still getting shortchanged.
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Old 11-12-2020, 10:32 AM
 
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This might be an advantage of watching IPTV via Hulu Live TV - every feed is individual so it doesn't have to size the video to fit the feed.
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