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james_bond

Why does Cable TV & DTH offer signal in 1080i ? Why not 1080p ?

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Posted · Original PosterOP

Why does Cable TV & DTH offer signal in 1080i ? Why not 1080p ?

In comparison to Cable TV when I watch videos using the USB port of my TV the picture quality is much better.

Is OTT the only option if I want to watch in progressive instead of interlaced ?

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17 minutes ago, james_bond said:

Why does Cable TV & DTH offer signal in 1080i ? Why not 1080p ?

In comparison to Cable TV when I watch videos using the USB port of my TV the picture quality is much better.

Is OTT the only option if I want to watch in progressive instead of interlaced ?

Because of bandwidth limitations. Cable TV uses QAM frequencies that are constantly carrying a datastream, whereas IPTV is "on demand" - because of this, many cable providers (or even the studios that provide the content to the broadcasters in each region) only offer cable TV in up to 1080i quality.


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Posted · Original PosterOP

@kirashi Thanks. In your opinion what is the best way to watch HD content on TV ? We will be moving to a new house soon & I am thinking of cancelling my digital cable connection.

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5 hours ago, james_bond said:

@kirashi Thanks. In your opinion what is the best way to watch HD content on TV ?

We will be moving to a new house soon & I am thinking of cancelling my digital cable connection.

If you still need TV, some of the online TV providers have solid offerings (at the expense of your internet bandwidth) like DirectTV, Sling TV, etc.

 

If you don't really care about TV much, I'd just stick to youtube or other online streaming providers (if they have what you want to watch).

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23 minutes ago, scottyseng said:

If you still need TV, some of the online TV providers have solid offerings with better quality (at the expense of your internet bandwidth) like DirectTV, Sling TV, etc.

 

If you don't really care about TV much, I'd just stick to youtube or other online streaming providers (if they have what you want to watch).

Online TV streaming quality is considerably worse than traditional cable or satellite. Bitrates are a fraction of QAM delivery and the streams are still 1080i, just upconverted to 1080p. 720p stays 720p. 

 

For me, transitioning off of Xfinity to YTTV showed a pretty massive dip in picture quality. I also gave Hulu and Sling a shot, same thing. You can't expect much from a 6-7Mbit 1080p 60Hz feed. Even less for lower resolutions and refresh rates.


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Posted · Original PosterOP
1 hour ago, Vitamanic said:

Online TV streaming quality is considerably worse than traditional cable or satellite. Bitrates are a fraction of QAM delivery and the streams are still 1080i, just upconverted to 1080p. 720p stays 720p.

Amazon Prime video & Netflix too are up converted ?

 

Never used them so I am curious.

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2 hours ago, james_bond said:

Why does Cable TV & DTH offer signal in 1080i ? Why not 1080p ?

In comparison to Cable TV when I watch videos using the USB port of my TV the picture quality is much better.

Is OTT the only option if I want to watch in progressive instead of interlaced ?

Because 1080i was the what was decided for ASTC 1.0 introduced in 1996. There is no "official" 60p signal in that spec.

 

ASTC 3.0 only came out this year, and 2.0 never made it into hardware.

 

ASTC 3.0 has:

- h.265 codec mandatory

- MPEG-H AA audio codec

- Legacy video using Main 10 3.1 (includes 720p), 1080i (1920 or 1440) using 4.1

- 4K at 5.2 profile, rec.2020 colorspace

- Uses OFDM instead of 8VSB

- Maximum 36Mbits.

 

Which means your OTA TV equipment is obsolete again. ASTC 3.0 is only in testing markets right now. Of note, ASTC 3.0 is IP-based, which means potentially other equipment can be used to "tune" it.

 

Considering that all of analog was phased out to ASTC 1.0 between 2009 and 2015, I wouldn't hold your breath for 4K OTA broadcasts until 2040.

 

Cable has also started switching to All-IP as well, and IMO is generally a downgrade since Cable modems were only ever designed to use "one" channel space originally, up to DOCSIS 2.0, so they only have 40Mbits of downlink capacity, and many people still have these devices.  Cable requires channel bonding to achieve anything greater, and channel bonding induces additional latency and error correction. So it may also take a decade of cable modem switch overs before cable companies manage to swap out all their old QAM tuners.

 

Most Cable channels are not broadcast in anything other than 1080i or 720p, and cable systems are free to decide on what codec, encryption on a per-channel basis with the assumption that the TV on the other end can only recieve 1080i or 720p. 

 

DSL/Fiber TV systems do not have this restriction, however their "TV boxes" are the exact same boxes that Cable companies have started using for their all-IP TV systems, and come with the same issues. So usually how it works is:

- Domestic carried TV - 1080i (eg ABC, CBS, NBC, etc)

- Premium TV - 1080i

- Sports - 720p60

- News - 1080i

- Cartoon channels - 1080i

 

However things change if you use the VOD, or apps like Netflix.

 

The VOD system is not restricted to the broadcast standards, and some cable/dsl systems call this "cloud PVR", in a sense, they are actually sending the original video data to the device, instead of the transcoded (with commercials) media, and the device decides if it needs to output 720p/1080i/1080p. However these devices also tend to use "1080p24" not 1080p60 if you indicate 1080p. 

 

Computer screens do NOT support 1080p24. 

 

Your cable/dsl/fiber provider doesn't really care if the equipment they give you is old/obsolete. IPTV systems cost them a lot less money to deploy since all three ISP types end up using the exact same equipment with only some customization in the firmware to skin the program guide and menus. IPTV systems are essentially the same grade of hardware that Android boxes people use for Kodi.

 

All-IP TV also allows people to use their iphone/ipad and third party Android boxes with the carriers system, though usually the software is janky (I tried to watch Star Trek Picard on my iPhone and it was window-boxed the entire time, despite the aspect ratio fitting the phone.)

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15 minutes ago, james_bond said:

Amazon Prime video & Netflix too are up converted ?

 

Never used them so I am curious.

No, I think he was referring to things like DirectTV. Here TV streams at 1080i are converted to 1080p for online video compatibility, whereas AP and Netflix use source recordings that are already in some progressive format and therefore don't do that.

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5 hours ago, Vitamanic said:

Online TV streaming quality is considerably worse than traditional cable or satellite. Bitrates are a fraction of QAM delivery and the streams are still 1080i, just upconverted to 1080p. 720p stays 720p. 

 

For me, transitioning off of Xfinity to YTTV showed a pretty massive dip in picture quality. I also gave Hulu and Sling a shot, same thing. You can't expect much from a 6-7Mbit 1080p 60Hz feed. Even less for lower resolutions and refresh rates.

Thank you for that information. That stings because I was considering internet TV as a replacement myself. I'm sort of self streaming TV by using my Home Run Prime with a Cable Card and emby.

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6 minutes ago, scottyseng said:

Thank you for that information. That stings because I was considering internet TV as a replacement myself. I'm sort of self streaming TV by using my Home Run Prime with a Cable Card and emby.

Most Internet TV implementations are not mature, except for a few edge cases outside the US where Fiber is the predominate internet connection.

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9 hours ago, james_bond said:

@kirashi Thanks. In your opinion what is the best way to watch HD content on TV ? We will be moving to a new house soon & I am thinking of cancelling my digital cable connection.

Over the Air TV is still a thing. I use a antenna connected in to an HD Homerun that feeds in to my network. My Plex server takes that signal and pushes the Live TV out to any device that can connect to Plex. The HD Homerun I have has 4 tuners, so I can watch/record up to 4 shows at a time. Part of the reason I have this setup is A) Its pretty much free, though you have to pay for the equpiment to get OTA TV, but honestly its better than paying for cable. B) I have a data cap, so for the bigger networks like ABC, Fox, NBC, and CBS I can record and watch those shows without having to use any internet data. 

 

The other way to get TV if you want more channels is to sub to a streaming service. Hulu Live, Youtube TV, Sling TV, and a few others exist. We used to use PSVue (Sony pulled the plug on the service) and then jumped to Hulu Live. But they kept rasing the rates, so we now have the Hulu no add plan, which doesnt do Live TV. 

 

Our setup is OTA TV via Plex. We also sub to Hulu No ads, Netflix, Prime (mainly for shipping), and currently we have Starz. But we have in the past subbed to Disney Plus and CBS All Access. The thing about streaming services is its easy to drop one and change to another when the shows you want to watch end. The Madolarian ended, so we went from Disney to CBS for Picard. Once that ended we dropped CBS and went to Starz because they had a $25 for 6 months deal. When that 6 months is up, we will probably dropped then and pick up another depending on how shows are. Will be doing Disney and CBS again when those corrisponding shows return. 

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On 5/24/2020 at 10:19 AM, Donut417 said:

Over the Air TV is still a thing. I use a antenna connected in to an HD Homerun that feeds in to my network. My Plex server takes that signal and pushes the Live TV out to any device that can connect to Plex. The HD Homerun I have has 4 tuners, so I can watch/record up to 4 shows at a time. Part of the reason I have this setup is A) Its pretty much free, though you have to pay for the equpiment to get OTA TV, but honestly its better than paying for cable. B) I have a data cap, so for the bigger networks like ABC, Fox, NBC, and CBS I can record and watch those shows without having to use any internet data. 

 

The other way to get TV if you want more channels is to sub to a streaming service. Hulu Live, Youtube TV, Sling TV, and a few others exist. We used to use PSVue (Sony pulled the plug on the service) and then jumped to Hulu Live. But they kept rasing the rates, so we now have the Hulu no add plan, which doesnt do Live TV. 

 

Our setup is OTA TV via Plex. We also sub to Hulu No ads, Netflix, Prime (mainly for shipping), and currently we have Starz. But we have in the past subbed to Disney Plus and CBS All Access. The thing about streaming services is its easy to drop one and change to another when the shows you want to watch end. The Madolarian ended, so we went from Disney to CBS for Picard. Once that ended we dropped CBS and went to Starz because they had a $25 for 6 months deal. When that 6 months is up, we will probably dropped then and pick up another depending on how shows are. Will be doing Disney and CBS again when those corrisponding shows return. 

I find people arguing for the quality of TV streams to be rather amusing. It’s probably due to the real-time codec being used, but I remember cable TV not being very impressive from a visual quality standpoint. Definitely recommend streaming services over cable. 
 

I’d definitely look into OTA if it was available. Sadly, not the case for me. 


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Welcome to the less than amusing world of broadcast standards. As a matter of fact, you can blame the Japanese for bringing 1080i to the world, at least somewhat. Early HD video tests by them (both tested in private and broadcasted to a more general public) were done in an 1125-line space, with 1035 or so of those lines being visible to the end viewer. From there, as it became more clear that digital broadcasting would be the way to go, 1920x1080i ended up being chosen, basically because it was a good enough resolution to future-proof on, while also working with existing analog HD standards decently enough. 

There's a reason you can capture MUSE Hi-Vision content competently using modern 1080i hardware when it's not 1080i.


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