6 ms·

To be fair, you weren't getting near-instantaneous full HD quality broadcasting with DVR support on your TV back then.

by Cyph0n 9y ago

dreamcompiler 9y ago
The problem is that there's no reason one couldn't design a TV that had both full HD and zero boot time with instantaneous channel switching. The reason such TVs don't exist is simply engineering laziness.
- Cyph0n 9y ago
  > The reason such TVs don't exist is simply engineering laziness. If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. > zero boot time That's not going to happen, ever, but I'll assume you meant "faster" boot times. Probably. Keep in mind that your average set-top box likely goes through a more complex secure boot process than most electronic devices you would ever interact with. Why? Because if people can run arbitrary firmware on a set-top box, your cable company would lose a shit ton of money. > instantaneous channel switching You are bound by the latency required to demodulate a signal being broadcast from some satellite ~30,000 km away from the receiver, decrypt the resulting stream, and finally decode it, all on the fly so you get a nice, continuous, stutter-free full HD broadcast. I am no expert, so there is probably way more stuff happening behind the scene that someone else could probably shed light on. The point of my comment was to demonstrate that things can sometimes be more complicated than they seem at first glance.
  - jimktrains2 9y ago
    When you change channels it has to wait for the next key frame before it can display video.
  - deleted 9y ago
    [deleted]
  - Yaggo 9y ago
    > If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. Simple solution: just put 10x decoders/tuners for most recently used channels. I don't think it's really an engineering problem but more about cost-effectiviness, i.e. not enough consumers are willing to pay the premium.
    - dreamcompiler 9y ago
      Exactly. Just having two decoders instead of one would drastically improve the 80% use case of consecutive channel surfing.
      - oasisbob 9y ago
        Some TVs including Samsungs have dual tuners. However, even if the read-ahead tuner was perfectly predictive you'd still need to flip through channels fairly slowly, otherwise you'll outrun it - about a second a channel.
  - averagewall 9y ago
    The distance to the satellite has nothing to do with it. You're using big numbers to exaggerate the problem. Decrypting and demodulating have be as fast as the data is coming, otherwise the delay would grow until you never saw the end of the show. So that's not the reason either.
    - oasisbob 9y ago
      Yes, the MPEG-2 decoder in your TV needs to be fast enough to keep up with the transmitted data rate, but that doesn't mean that it has instantaneous stream startup times. Your TV doesn't have the information it needs to start displaying MPEG-2+ATSC A/53 video for as long as 700ms. It needs to buffer quite a bit of timing information and at least an I-picture frame before it can start displaying anything: http://www.bretl.com/mpeghtml/startbuf.HTM http://www.bretl.com/mpeghtml/startbuf.HTM Not only that - the overall standard has tight timing tolerances to keep video arriving at the encoder/transmitter in-sync with audio/video leaving the decoder in your TV. It's not like MP3 streaming where every client has its own buffer size and time to start playing depending on network conditions, bitrate, etc. Having a reliable buffering process to keep receivers in-sync is a feature, not a bug.
      - dreamcompiler 9y ago
        And the way to solve this -- at least for the case of consecutive channel surfing -- is to have multiple decoders and multiple buffers. It's simply precaching.
        oasisbob 9y ago
        Eventually you're going to run into RF limits, especially if the signal is coming in over the air. You're sure this is engineering laziness? How much extra would you pay for a TV with faster channel changing?
        dreamcompiler 9y ago
        I'd pay extra for it. I'd pay even more for a TV that didn't spy on me and that couldn't update its firmware without my consent. But I'm probably not the target consumer.
  - dreamcompiler 9y ago
    Booting a computer doesn't have to be slow, and that's even more true for embedded computers. But making the boot process fast requires very careful engineering, which is both a rare skill and also not very well supported by management for consumer products companies.
  - TeMPOraL 9y ago
    > If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. The answer is never "engineers are lazy". The answer is, the company doesn't give a flying fuck about this problem and will actually prevent engineers from working on solving it, because they can sell you a TV perfectly well with this problem still present, and there's other work for engineers that makes TVs easier to sell than actually delivering a quality product.
- katastic 9y ago
  Mine is almost instantaneous. Except it's a lie because the TV is never actually off. It's "Standby" mode consumes a crap ton of wattage and the manual literally says "unplug it" if you intend to not use it for a long time. Not to mention the damn spyware that's included with it...
lostlogin 9y ago
Wish I could get that...
Piskvorrr 9y ago
Fair enough, but you were getting useful fallback, the image quality progressively degrading, and even with almost no image, the audio was still intelligible. With digital boradcast, it's all-or-nothing: all is fine, all is fine, until the error correction can no longer save you...and you get soundless picture, with block artifacts. Very useful for emergency broadcasts, when anything unicast will be overloaded as well.

To be fair, you weren't getting near-instantaneous full HD quality broadcasting with DVR support on your TV back then.

by Cyph0n 9y ago

To be fair, you weren't getting near-instantaneous full HD quality broadcasting with DVR support on your TV back then.

The problem is that there's no reason one couldn't design a TV that had both full HD and zero boot time with instantaneous channel switching. The reason such TVs don't exist is simply engineering laziness.

Cyph0n 9y ago
> The reason such TVs don't exist is simply engineering laziness. If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. > zero boot time That's not going to happen, ever, but I'll assume you meant "faster" boot times. Probably. Keep in mind that your average set-top box likely goes through a more complex secure boot process than most electronic devices you would ever interact with. Why? Because if people can run arbitrary firmware on a set-top box, your cable company would lose a shit ton of money. > instantaneous channel switching You are bound by the latency required to demodulate a signal being broadcast from some satellite ~30,000 km away from the receiver, decrypt the resulting stream, and finally decode it, all on the fly so you get a nice, continuous, stutter-free full HD broadcast. I am no expert, so there is probably way more stuff happening behind the scene that someone else could probably shed light on. The point of my comment was to demonstrate that things can sometimes be more complicated than they seem at first glance.
- jimktrains2 9y ago
  When you change channels it has to wait for the next key frame before it can display video.
- deleted 9y ago
  [deleted]
- Yaggo 9y ago
  > If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. Simple solution: just put 10x decoders/tuners for most recently used channels. I don't think it's really an engineering problem but more about cost-effectiviness, i.e. not enough consumers are willing to pay the premium.
  - dreamcompiler 9y ago
    Exactly. Just having two decoders instead of one would drastically improve the 80% use case of consecutive channel surfing.
    - oasisbob 9y ago
      Some TVs including Samsungs have dual tuners. However, even if the read-ahead tuner was perfectly predictive you'd still need to flip through channels fairly slowly, otherwise you'll outrun it - about a second a channel.
- averagewall 9y ago
  The distance to the satellite has nothing to do with it. You're using big numbers to exaggerate the problem. Decrypting and demodulating have be as fast as the data is coming, otherwise the delay would grow until you never saw the end of the show. So that's not the reason either.
  - oasisbob 9y ago
    Yes, the MPEG-2 decoder in your TV needs to be fast enough to keep up with the transmitted data rate, but that doesn't mean that it has instantaneous stream startup times. Your TV doesn't have the information it needs to start displaying MPEG-2+ATSC A/53 video for as long as 700ms. It needs to buffer quite a bit of timing information and at least an I-picture frame before it can start displaying anything: http://www.bretl.com/mpeghtml/startbuf.HTM http://www.bretl.com/mpeghtml/startbuf.HTM Not only that - the overall standard has tight timing tolerances to keep video arriving at the encoder/transmitter in-sync with audio/video leaving the decoder in your TV. It's not like MP3 streaming where every client has its own buffer size and time to start playing depending on network conditions, bitrate, etc. Having a reliable buffering process to keep receivers in-sync is a feature, not a bug.
    - dreamcompiler 9y ago
      And the way to solve this -- at least for the case of consecutive channel surfing -- is to have multiple decoders and multiple buffers. It's simply precaching.
      - oasisbob 9y ago
        Eventually you're going to run into RF limits, especially if the signal is coming in over the air. You're sure this is engineering laziness? How much extra would you pay for a TV with faster channel changing?
        dreamcompiler 9y ago
        I'd pay extra for it. I'd pay even more for a TV that didn't spy on me and that couldn't update its firmware without my consent. But I'm probably not the target consumer.
- dreamcompiler 9y ago
  Booting a computer doesn't have to be slow, and that's even more true for embedded computers. But making the boot process fast requires very careful engineering, which is both a rare skill and also not very well supported by management for consumer products companies.
- TeMPOraL 9y ago
  > If your answer to the question "why can't a billion dollar industry provide me with instantaneous channel switching?" is "because they are lazy", you are severely misguided (at the very least!). There are hundreds of extremely talented engineers working full-time on these problems. If the solution were as easy as you propose, the issues would be solved. The answer is never "engineers are lazy". The answer is, the company doesn't give a flying fuck about this problem and will actually prevent engineers from working on solving it, because they can sell you a TV perfectly well with this problem still present, and there's other work for engineers that makes TVs easier to sell than actually delivering a quality product.
katastic 9y ago
Mine is almost instantaneous. Except it's a lie because the TV is never actually off. It's "Standby" mode consumes a crap ton of wattage and the manual literally says "unplug it" if you intend to not use it for a long time. Not to mention the damn spyware that's included with it...

lostlogin 9y ago

Wish I could get that...

Piskvorrr 9y ago

Fair enough, but you were getting useful fallback, the image quality progressively degrading, and even with almost no image, the audio was still intelligible. With digital boradcast, it's all-or-nothing: all is fine, all is fine, until the error correction can no longer save you...and you get soundless picture, with block artifacts. Very useful for emergency broadcasts, when anything unicast will be overloaded as well.