10 ms·

There are many other things that are broken too. My fancy expensive name-brand digital TV takes a full minute to boot up from a cold start, longer than it took

• stinkytaco 15y ago
  >We won't even get into how 720 screens don't really have 720 display pixels so even perfect size matches are resampled and interpolated, or how often I find I have to manually change the aspect ratio because it wasn't able to figure it out on its own. This drives me crazy. I have a computer hooked up to my TV (for the same reason as the OP, we basically watch just streaming or my digitized DVD collection) and every time I upgrade the display drivers, and sometimes just randomly, the display goes wonky and I have to fix it by hand. I don't have to do that with my computer monitor...
  • Danieru 15y ago
    For those curious; kernel hacker Matthew Garrett wrote a great post on this subject: http://mjg59.dreamwidth.org/8705.html http://mjg59.dreamwidth.org/8705.html
  • Raphael 15y ago
    Yeah, I don't know why AMD decided thought digital TVs would be susceptible to under-scan or over-scan.
• jpdoctor 15y ago
  > We won't even get into how 720 screens don't really have 720 display pixels so even perfect size matches are resampled and interpolated Since there's nowhere near 720 pixels x 60 frames/sec worth of information being sent to your TV, who cares?
  • dpark 15y ago
    Maybe because resampling and interpolation are more damaging to lower-resolution streams? Also, depending on the video source, there might very well be a 720p x 60Hz signal being sent to the TV.
    • jpdoctor 15y ago
      > 720p x 60Hz signal being sent to the TV. Let's do the arithmetic: 720p is 1280x720 pixels RGB = 24 bits/pixel 60 frames/sec 1280x720x24x60 = 1.3 Gbps For comparison: Full broadcast HD is around 15 Mbps Why people think they can see full 720p worth of information is beyond me. EDIT: Pay attention to the last sentence and the posts above. Of course I don't think people can see 1.3G worth of info. Again: Why people think they can see full 720p worth (=1.3G) of information is beyond me.
      • agscala 15y ago
        If you don't think it's compressed, you're kidding yourself
      • dpark 15y ago
        > 1280x720x24x60 = 1.3 Gbps So your argument is that compression doesn't exist? Do you also listen to 128kb WAV files and argue that they are equivalent to 128kb MP3s? > Why people think they can see full 720p worth of information is beyond me. From a distance of about 8 feet on a TV about 50 inches in size, the difference between 720p and 1080p is visible to a person with 20/20 vision. The eye cannot perceive 720p worth of pixels at once, but in the small spot the center of a person's vision is on, pixel density matters a lot.
  • mbell 15y ago
    I'm not really sure what your trying to say but the stream is decompressed at the cable box or at the the over the air HD receiver. HDMI 1.3 and 1.4 support up to 10.2Gb/sec bandwidth. The video is not compressed, the audio may or may not be. So why would you think that there isn't 720p x 60fps being sent to the tv? The max video you can get through HDMI is 4096×2160p24 @ 24bit color completely uncompressed which is several times the bandwidth needed for 1280x720p60 @ 24bit color.
• potatolicious 15y ago
  And this is why I groan when Samsung easily dismisses rumors that Apple is about to enter the TV space. The UX around TVs is horrific right now, and people put up with it because that's how it is. There's enormous room for a dramatic UX improvement and it doesn't seem like the incumbents realize this.
  • blogimus 15y ago
    Like climate control in your house
    • larrik 15y ago
      I know what you are referring to, but I would say no. Not like that at all. The ideal climate control interface should never even have to be looked at. It should just know what to do with your heating/cooling equipment to make your house comfortable. A ideal TV interface should help you do a lot of things, and ideally be fast in the process. (The article was down while I was writing this comment, but cable equipment and TVs drive me nuts.)
      • Karunamon 15y ago
        >A ideal TV interface should help you do a lot of things, That's kind of a judgement call - there's nothing wrong with a minimal interface that does what you want it to and nothing more. Kind of like Chrome as a browser - Google's big thing with its design was minimal and out of your way, so you can focus on the web page (the reason you're running the browser in the first place).
        • seabee 15y ago
          I think there's room for both. Firefox is pretty popular precisely because of all the things it can do. In any case, modern TVs suck at doing either of these things. I wouldn't mind which way they go as long as they do one of them.
  • r00fus 15y ago
• SiVal 15y ago
  Here's a question for my fellow amateur economists: What happens to the quality of broadcast television when you increase the supply of broadcast channel-hours by a factor of 50 and you don't increase the supply of viewers at all? I used to watch TV, like most people. Then, in the 1990's, the number of channels started increasing. More options, great. Twice as many channels did allow for more specialization, so maybe there were twice as many things I wanted to watch. When it reached four times as many channels, though, there were still only twice as many things I wanted to watch. Ten times as many channels, and now I wasn't sure if there were even twice as many as in the old days, because the budgets for the good shows were being spread among more shows to provide vehicles for more ads in all those new broadcast channel-hours. Then, along came TiVo. Ah, TV was fun again. I could skim the cream. Couldn't imagine life without it. But as the years passed, the things I grabbed with TiVo were losing quality, too, seemingly bleeding budget to the shows "out there" that my TiVo and I ignored. Then, my TV set broke. I assumed I'd have to get a new one quickly because, of course, everyone had to have a TV, right? I was sure I'd go crazy without it. But I didn't. As time passed, I found I grew less motivated to get a new one, not more. Well, after years of no TV, we finally got one a few weeks ago, so we wouldn't have to gather 'round the laptop for Netflix and slide shows of family vacations. The image is spectacular. But I can't believe what I'm so clearly seeing. They may call themselves The Travel Channel, Discovery Channel, History Channel, Food Network, Science Channel, or whatever, but they're all "Paid Programming", reality for rednecks, and pseudoscience for suckers, punctuated by screaming ads. Even the islands of quality have clearly suffered extreme beach erosion. But at least DVR technology has improved. Sorry, JUST KIDDING. You'd think that after years of Moore's Law, Comcast could make a cable box that didn't act as though I was waking it from a nap with each key press. You'd think that a product called an "HD DVR" would have an HD interface (wouldn't you?), instead of one with the display resolution of the lower half of a Nintendo DS. You'd think with so few needles hidden in the haystack of broadcasting, their interface would help you navigate the guide and find shows to watch, but apparently nobody at Comcast HQ has ever used Amazon to find a book. Either that or they never watch TV.
  • rdtsc 15y ago
    I have a TV but I am not using it to watch cable broadcast. I have cable but just because it came in a stupid bundle with the internet. So the TV is there but it is used to watch Netflix, Youtube, Amazon and Hulu videos. It is used for games, skype (there is a camera attached to it), also used to browse pictures (since it has a better resolution and color profile than my laptop). And I have noticed the same effect in respect to commercials. I cannot stand watching them and refuse to watch anything that suddenly interrupts and starts showing commercials (so I stopped using Hulu eventually as well because of it). Extended family members think I am crazy for being so "fussy" and I think they are crazy for putting up with annoying commercials.
• WiseWeasel 15y ago
  For the latter issue (and possibly slightly helping the first issue as well), switch your TV to 'game' mode. This is a low-latency mode that eliminates certain image processing in order to reduce the lag between signal and display. That should allow you to change channels faster.
  • TylerE 15y ago
    No, it won't. Game mode reduces latency on the order of 2-3 frames, so a 0.1sec or less. The issue is that the tuner has to consume a complete data frame before it can start displaying, since it needs to get a keyframe for the codec to start working.
    • WiseWeasel 15y ago
      Hmm, I think I may have noticed that issue switching between HD channels at times, but SD channels maybe don't have the same issue? I guess the time before a key frame appears can vary from up to a second to as low as 0, depending on when you happen to switch. It could be that a few frames, or 0.1 seconds becomes significant at that point, though you're right that it's likely to make little difference. I was not aware of the key frame issue until now, though; thanks for enlightening.
      • TylerE 15y ago
        Basically the way modern video codecs work is that they only fully encode every Nth frame, where N is some smallish integer - 15 or 30 is common. From one keyframe to the next, they essentially encode a diff from the prior frame. The idea is that most of the regions of the frame have very little change over short timescales. It's a tradeoff. More keyframes means faster seeking (when you seek in a video, it has to start from a keyframe too, for the same reasons), but larger data rates for the same image quality.
• brigade 15y ago
  >have to manually change the aspect ratio because it wasn't able to figure it out on its own. For HDMI connections, this isn't the TV's fault (actually I think my TV doesn't even let you change the aspect ratio for HDMI inputs.) For SD component/composite, there is no aspect ratio information in the signal so the TV cannot determine it correctly and generally defaults to assuming 16:9 because most people stupidly prefer 4:3 content to be stretched to 16:9.
• naner 15y ago
  or how often I find I have to manually change the aspect ratio because it wasn't able to figure it out on its own. This is a feature not a bug. Most people don't understand aspect ration and in fact will get upset if a standard def video doesn't fill the HD screen. Actually, it is probably just laziness on the manufacturers part but it works out well for most consumers.
  • julian37 15y ago
    I think you're right, and it makes me sad. Who would prefer a distorted image over a non-distorted one, black bars or not? The only explanation I have for this is sense of entitlement: "I paid dearly for each of these pixels so you better use all of them, no matter how bad the picture looks like!"
  • justincormack 15y ago
    Also because there were no standards for widescreen in analogue times. Even broadcast TV sometimes mixes aspect ratios incorrectly.
  • llamalife 15y ago
    My TV has six different aspect ratio modes. My satellite box has several more on top of that, in addition to choices about what resolutions it'll output in, in different situations. Personally, I'd like that to drop that down to two options: 'black bars' or 'fill the screen', and use sensible defaults for everything else.
• mbell 15y ago
  This is generally not an issue with your TV (unless you using an internal OTA HD tuner) but rather a poorly made cable box. Generally the cable box is responsible for channel changing, buffering for decode and other things. The stream is sent, uncompressed, to the TV over HDMI. Now your TV may be trying to do some processing on the HDMI signal but that should not effect channel changing at all as the TV isn't changing channels, its just processing a stream. If the cable box borks the stream in the process of changing channels, that is the cable box's fault. This really stems from relative non-existent competition in the cable box industry. The consumer doesn't usually get to choose, its just whoever got the deal with Comcast or whoever. The solution to this, which has been and will continue to be fought adamantly by cable providers, is allowing CableCARD/M-CARD support. It lets you plug in a little card that will allow any device to decode the cable stream. Its not a full solution though, most people just don't care and the cablebox is usually 'free', why pay for something better?
  • dmoo 15y ago
    I'm guessing that most of the lag is in decrypting the broadcast stream on the fly from nagra 3 or whatever the current version is. For sure in Ireland there was a big business in selling 'dodgy' boxes which could decrypt all channels when you had paid for only a basic subscription to cable. The encryption upgrade a few years ago killed all of them but made the cable boxes run as slowly as treacle when it came to epg or channel switching
    • demallien 15y ago
      Well, encryption is certainly part of the story. DVB encryption uses messages called ECMs to distribute the key that is used from the receipt of the ECM through to the receipt of the next ECM. The time between two ECMs is called the crypto period and is generally in the order of a few seconds. The average wait time to get an ECM on changing channels is of course half a crypto period. The other major source of delay is video compression, as defined by MPEG. MPEG uses bi-directional compression in the time domain, which means that frames are sent out of order, which in turn means that they have to be buffered. Furthermore, a complete frame, known as an I frame, is only sent every 10 or so frames (it depends on the profile of the transmission channel - is it lossy or not for example). As the P and B frames are basically diffs from the base I frame, you can't decode an image until you have received an I frame. This too introduces a delay of typically 0.25 seconds, and is the reason why even unencrypted digital is slower for changing channels than analog.
• mjwalshe 15y ago
  realy my sony takes < 3 seconds