7 ms·

Interesting to see the angry comments about how Digital TV fails more than Analog. I don't watch TV so I dunno how is the situation in my country, but I did no

Interesting to see the angry comments about how Digital TV fails more than Analog. I don't watch TV so I dunno how is the situation in my country, but I did noticed when seeing broadcasts on public TVs (for example in bars and restaurants showing sports) that compression issues happen, decoding issues happen, and the whole thing is laggy, most obvious when you are seeing sports, during analog TV times, I would hear the cheers and fireworks after goals, victories and so on, all at same time, now I hear it staggered, with seemly poorer people cheering first, I assume because they have analog TVs and radios.

Telemakhos 5y ago
I grew up with analog OTA TV. When you changed channels, the change was instant. We got a handful of local channels. Then, we got analog cable. When you changed channels, the change was still instant, and you used the same remote as for OTA TV (if you were rich enough for a remote) because the cable just plugged straight into the back of the TV. We got a bunch of channels, including the local ones from before, a handful of new channels worth watching, and a ton of others that were absolutely worthless. This was expensive, but at least cable channels were ad-free... until they were not. Next we got digital cable. This marked a real downturn in user experience. The signal had to be processed by a box that we had to rent instead of just plugging the cable into the TV. We needed a new box and new remote for every TV. Theoretically the new remotes could replace the old ones, but that never worked out in practice. You always needed the old remote for some function not available or not programmed properly on the new one. The boxes also took forever to switch between channels. Channels now were no longer straightforward one-channel-to-one-station mappings, but you had subchannels and HD/SD versions of the same channel. My parents never understood that while they were alive and usually ended up watching the SD channel instead of the HD because it was all they could find. In fact, for them, there was usually no increase in picture quality, just in price and inconvenience. Finally I inherited the TVs, but I never watch them, and I cancelled the cable subscription. I got a digital TV antenna, and it sometimes picks up most of the local stations, which were all that my parents ever watched, but usually it glitches or fails. Changing channels still takes forever, but at least the antenna just plugs into the back of the TV without a rented box. Of what is available on OTA television, as with what was available on cable, there isn't enough to keep my attention. Most of it is vulgar trash riddled with advertisements. I've gone back to reading books for entertainment. They don't require any cable or antenna, no rented box, no remote control. I can get whatever I want from the library (for free!) or Amazon, and I can change books without lag. The signal never drops or glitches. I can take my books with me anywhere, including outside. I'm happier now.
- bitwize 5y ago
  Well, ackshually... Cable systems in the USA took advantage of more frequencies than were available over terrestrial television to get more channels. This is because the cable signal was still RF, but not subject to radio interference in any significant way because it came through a cable. The upshot of this was that unless your TV was "cable-ready", i.e., capable of tuning the additional frequencies, in order to use even analog cable you needed a set-top box. It took a few years for cable-ready TVs to hit the US market -- but by the 90s they were ubiquitous.
- VLM 5y ago
  Latency always goes up with technology. Think of streaming or video on demand services where its now up to five seconds to change.
  - agumonkey 5y ago
    It does happen on computing too. Even on very recent machines, very recent OS kernels you can notice the layers. Very odd to see.
    - hulitu 5y ago
      Because the developers are lazy. Why do we need 20 layers of libraries to draw a rectangle ? Give a developer a library and he will use it.
      - bitwize 5y ago
        Give the developer no library and they will find a way to slam the bits into VRAM. That said, the friction among modern devs to go from zero to cross-platform app is much lower with Electron than it is any other framework. So learn to love Electron because it is here to stay.
  - dreamcompiler 5y ago
    > Latency always goes up with technology. It's certainly possible to build non-causal signal processors for broadcast TV by using multiple tuners that buffer channel N+1 while you're watching channel N. You could do it for streaming services too by using statistics (or--dare I say it--AI) to predict what movie the user is most likely to sample next. It might make the decoder cost an extra $2, and that's probably why nobody does it.
tomatocracy 5y ago
The differences in latency from the live event to people seeing it were pretty apparent in the UK during the recent Euro 2020 tournament - I was surprised how many were evidently watching on internet streaming services by the length of the delays in reaction vs what I saw via satellite (the delay for satellite vs terrestrial/cable is small by comparison, especially since both of those went digital). If you want the lowest latency to the live event, analogue radio is probably still the best for these types of things.
- buggeryorkshire 5y ago
  The BBC 4K streams were a good 70 seconds behind broadcast. Fastest/earliest stream is SD on Freeview from my testing.
  - ksec 5y ago
    I remember the standard delay for Analog or Satellite Broadcast were 3 - 5 secs due to some betting arrangement. So I really dont see why Internet Broadcasting cant be within that limit as well.
literallyaduck 5y ago
Partial success of signal mattered in rural emergencies, but with ubiquitous cell phones the need disappeared. With improving internet coverage providing on demand media, the need for over the air television is shrinking and the spectrum can be better used.
- fomine3 5y ago
  And there's still best broadcast method for emergency: analog radio
szczys 5y ago
I still use an over-the-air antenna on a daily basis (and record from it using MythTV with ATSC tuners in a computer). The changeover from analog has been a bit of a give and take. With analog broadcast, if you were a bit too far away you would still get a fuzzy image and sounds that had some interference with it. Now if you're a bit too far away the picture breaks up and the audio sounds like auto-tune. It doesn't take much of that to make it unwatchable. On the other hand, when you get a solid signal the picture is amazing versus the standard-def of analog broadcasts. Add to this the benefit of multiple sub-channels on each broadcast channel and you get a lot more watching options. I've installed an attic antenna and a pre-amplifier that supplies great signal to all coax (CATV) outlets in the house. That hardware cost what 1-2 months of cable TV subscription would have and that was years and years ago. On balance the digital changeover has been much better in my experience.
- toast0 5y ago
  > On the other hand, when you get a solid signal the picture is amazing versus the standard-def of analog broadcasts. Add to this the benefit of multiple sub-channels on each broadcast channel and you get a lot more watching options. Subchannels is kind of nice, but junky content with junky compression is worse than a more limited set of snowy channels. Now, when they do broadcast stuff with enough bandwidth, and you're above the cliff the whole time, it's nice.
salamandersauce 5y ago
It is worse if you have poor signal. Digital either works and looks great or it's not watchable. An analog station might look kinda snowy but be completely watchable. I used to be able to get a few channels before the switchover on my bedroom TV with rabbit ears, after the switchover I got 1 or 2 on a good day because the signal strength was just not strong enough.
- yholio 5y ago
  Snowy analog with intelligible sound translates to about 40dB signal to noise ratio. That's a SNR where digital will deliver crystal clear image. When digital becomes glitchy, you will absolutely be unable to watch analogue, you will have trouble maintaining vertical and horizontal sync and the sound will be drowned in noise.
  - blendergeek 5y ago
    So that may be true, in theory. In reality, the switch from Analog to Digital means that while people in Urban areas have more clearer channels, people in rural areas (who could watch snow covered analog TV) now have fewer if any channels. Even if a mathematical calculation says that my TV should work great, I still have nothing if I can't pick up any channels.
    - uxp100 5y ago
      Even in urban areas we lost broadcasters in the transition to digital. It is just worse in a lot of ways. I don't care that my morning weather report is clearer in picture, if it stutters seemingly randomly. It's not as far as unintelligible, just fantastically irritating.
  - dkarl 5y ago
    There must be some other factor at work, then, because I had the same experience when I didn't have cable around 2010. For a few big sports events I tried to get broadcasts, and analog was watchable (by analog standards) when digital was unwatchable because of frequent glitching. Buying a fancy antenna did not help. Maybe television stations did not care enough about broadcast anymore to invest in digital broadcasting capability that matched the power of their old analog broadcasts.
unavoidable 5y ago
It probably has to do with the failure mode rather than actual rate of failure, although it may be perceived differently. When digital signals "fail" (usually just minor interference or some power fluctuation), you usually just get a black screen or a picture that cuts in and out. When analog signals "failed" (in the same interference or fluctuation) then you likely got a distorted image/sound/colour for a few seconds but it didn't really interrupt your viewing experience. It is an interesting observation that it seems in areas where there was still analog and digital transmission in parallel, that the "live" analog signal was "faster".
Robotbeat 5y ago
Yeah, I think it’s a little ironic that the analog error by necessity had lower latency because buffers were expensive. In someways the world as a whole had these brief experiences of synchronized emotion… everyone hearing the same exact thing within a second that with a long digital buffers caused by cheap memory we no longer experience… buffers can be several seconds, maybe over a minute in total even for live events. Buffer bloat killed cybernetic synchronicity. ;)
- interestica 5y ago
  > Buffer bloat killed cybernetic synchronicity. There's something very interesting about this concept of "cyber-sync" - when is now? Is your now different from mine?
raverbashing 5y ago
I'm not so sure what kind of error-correction ATSC has compared to DTB and ISTB standards, but the 8VSB modulation is not particularly great Also ISTB has the idea of a 'mobile' channel, which can be useful in low SNR conditions (it is worse for pretty much anything else, though)
- rescbr 5y ago
  ATSC has only one FEC parameter compared to DVB-T and ISDB-T, which also have more robust modulation schemes. ISDB-T includes an interleaver that makes it more resilient to impulsive noise compared to DVB-T. ISDB-T modulation scheme is very interesting. It is comprised of 13 sub-carriers ("segments"), and by spec, one of those can be the "mobile" channel (called 1seg, as it occupies one of the 13 segments and leaves 12 for the main mux). It can have different modulation parameters from the 12 main sub-carriers, so you can make it more robust with less available bandwidth and make the main mux less robust but with more bandwidth. IIRC there are other ways to distribute the ISDB-T segments but I don't remember how out of spec it would be. Most 13-segment receivers (ie, TVs, set-top boxes, some USB adapters) wouldn't care (at least 10 years ago they didn't care) and it would work, though.

Telemakhos 5y ago

I grew up with analog OTA TV. When you changed channels, the change was instant. We got a handful of local channels. Then, we got analog cable. When you changed channels, the change was still instant, and you used the same remote as for OTA TV (if you were rich enough for a remote) because the cable just plugged straight into the back of the TV. We got a bunch of channels, including the local ones from before, a handful of new channels worth watching, and a ton of others that were absolutely worthless. This was expensive, but at least cable channels were ad-free... until they were not. Next we got digital cable. This marked a real downturn in user experience. The signal had to be processed by a box that we had to rent instead of just plugging the cable into the TV. We needed a new box and new remote for every TV. Theoretically the new remotes could replace the old ones, but that never worked out in practice. You always needed the old remote for some function not available or not programmed properly on the new one. The boxes also took forever to switch between channels. Channels now were no longer straightforward one-channel-to-one-station mappings, but you had subchannels and HD/SD versions of the same channel. My parents never understood that while they were alive and usually ended up watching the SD channel instead of the HD because it was all they could find. In fact, for them, there was usually no increase in picture quality, just in price and inconvenience. Finally I inherited the TVs, but I never watch them, and I cancelled the cable subscription. I got a digital TV antenna, and it sometimes picks up most of the local stations, which were all that my parents ever watched, but usually it glitches or fails. Changing channels still takes forever, but at least the antenna just plugs into the back of the TV without a rented box. Of what is available on OTA television, as with what was available on cable, there isn't enough to keep my attention. Most of it is vulgar trash riddled with advertisements. I've gone back to reading books for entertainment. They don't require any cable or antenna, no rented box, no remote control. I can get whatever I want from the library (for free!) or Amazon, and I can change books without lag. The signal never drops or glitches. I can take my books with me anywhere, including outside. I'm happier now.

bitwize 5y ago
Well, ackshually... Cable systems in the USA took advantage of more frequencies than were available over terrestrial television to get more channels. This is because the cable signal was still RF, but not subject to radio interference in any significant way because it came through a cable. The upshot of this was that unless your TV was "cable-ready", i.e., capable of tuning the additional frequencies, in order to use even analog cable you needed a set-top box. It took a few years for cable-ready TVs to hit the US market -- but by the 90s they were ubiquitous.
VLM 5y ago
Latency always goes up with technology. Think of streaming or video on demand services where its now up to five seconds to change.
- agumonkey 5y ago
  It does happen on computing too. Even on very recent machines, very recent OS kernels you can notice the layers. Very odd to see.
  - hulitu 5y ago
    Because the developers are lazy. Why do we need 20 layers of libraries to draw a rectangle ? Give a developer a library and he will use it.
    - bitwize 5y ago
      Give the developer no library and they will find a way to slam the bits into VRAM. That said, the friction among modern devs to go from zero to cross-platform app is much lower with Electron than it is any other framework. So learn to love Electron because it is here to stay.
- dreamcompiler 5y ago
  > Latency always goes up with technology. It's certainly possible to build non-causal signal processors for broadcast TV by using multiple tuners that buffer channel N+1 while you're watching channel N. You could do it for streaming services too by using statistics (or--dare I say it--AI) to predict what movie the user is most likely to sample next. It might make the decoder cost an extra $2, and that's probably why nobody does it.

tomatocracy 5y ago

The differences in latency from the live event to people seeing it were pretty apparent in the UK during the recent Euro 2020 tournament - I was surprised how many were evidently watching on internet streaming services by the length of the delays in reaction vs what I saw via satellite (the delay for satellite vs terrestrial/cable is small by comparison, especially since both of those went digital). If you want the lowest latency to the live event, analogue radio is probably still the best for these types of things.

buggeryorkshire 5y ago
The BBC 4K streams were a good 70 seconds behind broadcast. Fastest/earliest stream is SD on Freeview from my testing.
- ksec 5y ago
  I remember the standard delay for Analog or Satellite Broadcast were 3 - 5 secs due to some betting arrangement. So I really dont see why Internet Broadcasting cant be within that limit as well.

literallyaduck 5y ago

Partial success of signal mattered in rural emergencies, but with ubiquitous cell phones the need disappeared. With improving internet coverage providing on demand media, the need for over the air television is shrinking and the spectrum can be better used.

fomine3 5y ago
And there's still best broadcast method for emergency: analog radio

szczys 5y ago

I still use an over-the-air antenna on a daily basis (and record from it using MythTV with ATSC tuners in a computer). The changeover from analog has been a bit of a give and take. With analog broadcast, if you were a bit too far away you would still get a fuzzy image and sounds that had some interference with it. Now if you're a bit too far away the picture breaks up and the audio sounds like auto-tune. It doesn't take much of that to make it unwatchable. On the other hand, when you get a solid signal the picture is amazing versus the standard-def of analog broadcasts. Add to this the benefit of multiple sub-channels on each broadcast channel and you get a lot more watching options. I've installed an attic antenna and a pre-amplifier that supplies great signal to all coax (CATV) outlets in the house. That hardware cost what 1-2 months of cable TV subscription would have and that was years and years ago. On balance the digital changeover has been much better in my experience.

toast0 5y ago
> On the other hand, when you get a solid signal the picture is amazing versus the standard-def of analog broadcasts. Add to this the benefit of multiple sub-channels on each broadcast channel and you get a lot more watching options. Subchannels is kind of nice, but junky content with junky compression is worse than a more limited set of snowy channels. Now, when they do broadcast stuff with enough bandwidth, and you're above the cliff the whole time, it's nice.

salamandersauce 5y ago

It is worse if you have poor signal. Digital either works and looks great or it's not watchable. An analog station might look kinda snowy but be completely watchable. I used to be able to get a few channels before the switchover on my bedroom TV with rabbit ears, after the switchover I got 1 or 2 on a good day because the signal strength was just not strong enough.

yholio 5y ago
Snowy analog with intelligible sound translates to about 40dB signal to noise ratio. That's a SNR where digital will deliver crystal clear image. When digital becomes glitchy, you will absolutely be unable to watch analogue, you will have trouble maintaining vertical and horizontal sync and the sound will be drowned in noise.
- blendergeek 5y ago
  So that may be true, in theory. In reality, the switch from Analog to Digital means that while people in Urban areas have more clearer channels, people in rural areas (who could watch snow covered analog TV) now have fewer if any channels. Even if a mathematical calculation says that my TV should work great, I still have nothing if I can't pick up any channels.
  - uxp100 5y ago
    Even in urban areas we lost broadcasters in the transition to digital. It is just worse in a lot of ways. I don't care that my morning weather report is clearer in picture, if it stutters seemingly randomly. It's not as far as unintelligible, just fantastically irritating.
- dkarl 5y ago
  There must be some other factor at work, then, because I had the same experience when I didn't have cable around 2010. For a few big sports events I tried to get broadcasts, and analog was watchable (by analog standards) when digital was unwatchable because of frequent glitching. Buying a fancy antenna did not help. Maybe television stations did not care enough about broadcast anymore to invest in digital broadcasting capability that matched the power of their old analog broadcasts.

unavoidable 5y ago

It probably has to do with the failure mode rather than actual rate of failure, although it may be perceived differently. When digital signals "fail" (usually just minor interference or some power fluctuation), you usually just get a black screen or a picture that cuts in and out. When analog signals "failed" (in the same interference or fluctuation) then you likely got a distorted image/sound/colour for a few seconds but it didn't really interrupt your viewing experience. It is an interesting observation that it seems in areas where there was still analog and digital transmission in parallel, that the "live" analog signal was "faster".

Robotbeat 5y ago

Yeah, I think it’s a little ironic that the analog error by necessity had lower latency because buffers were expensive. In someways the world as a whole had these brief experiences of synchronized emotion… everyone hearing the same exact thing within a second that with a long digital buffers caused by cheap memory we no longer experience… buffers can be several seconds, maybe over a minute in total even for live events. Buffer bloat killed cybernetic synchronicity. ;)

interestica 5y ago
> Buffer bloat killed cybernetic synchronicity. There's something very interesting about this concept of "cyber-sync" - when is now? Is your now different from mine?

raverbashing 5y ago

I'm not so sure what kind of error-correction ATSC has compared to DTB and ISTB standards, but the 8VSB modulation is not particularly great Also ISTB has the idea of a 'mobile' channel, which can be useful in low SNR conditions (it is worse for pretty much anything else, though)

rescbr 5y ago
ATSC has only one FEC parameter compared to DVB-T and ISDB-T, which also have more robust modulation schemes. ISDB-T includes an interleaver that makes it more resilient to impulsive noise compared to DVB-T. ISDB-T modulation scheme is very interesting. It is comprised of 13 sub-carriers ("segments"), and by spec, one of those can be the "mobile" channel (called 1seg, as it occupies one of the 13 segments and leaves 12 for the main mux). It can have different modulation parameters from the 12 main sub-carriers, so you can make it more robust with less available bandwidth and make the main mux less robust but with more bandwidth. IIRC there are other ways to distribute the ISDB-T segments but I don't remember how out of spec it would be. Most 13-segment receivers (ie, TVs, set-top boxes, some USB adapters) wouldn't care (at least 10 years ago they didn't care) and it would work, though.