# Why No Ad-blocking for Cable TV? **URL:** \ **Category:** Factual Questions\ **Created:** [July 12, 2016, 6:09pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733 "2016-07-12T18:09:56Z")\ **Posts on this page:** 7\ **Page:** 3
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [July 13, 2016, 6:10pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/41 "2016-07-13T18:10:42Z")
No, obviously not. Unless you’re the type to assume all cars are “self-driving.” Having a flunky (or spouse or child) zap the commercials for you is not a terribly useful system for most people. ---
**Author:** ![Slash1972](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/slash1972/32/6461_2.png) [@Slash1972](https://boards.straightdope.com/u/Slash1972)\ **Post date:** [July 13, 2016, 6:36pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/42 "2016-07-13T18:36:34Z")
> [@Amateur\_Barbarian](#): > > No, obviously not. Unless you’re the type to assume all cars are “self-driving.” > > Having a flunky (or spouse or child) zap the commercials for you is not a terribly useful system for most people. Having a flunky (spouse or child) change the channel WAS a terribly useful system for most people before remote controls were invented 😃 I just want to win the nickel 🙂 ---
**Author:** ![Atamasama](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atamasama/32/12961_2.png) [@Atamasama](https://boards.straightdope.com/u/Atamasama)\ **Post date:** [July 13, 2016, 7:20pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/43 "2016-07-13T19:20:25Z")
> [@Slash1972](#): > > Does your definition of “ad-zapper” include a system that includes a human being? Only if his name is Ed Zappa. ---
**Author:** ![Terry\_Kennedy](https://avatars.discourse-cdn.com/v4/letter/t/c57346/32.png) [@Terry\_Kennedy](https://boards.straightdope.com/u/Terry_Kennedy)\ **Post date:** [July 13, 2016, 9:52pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/44 "2016-07-13T21:52:37Z")
The difference between TiVo and (for example) a satellite TV DVR is that TiVo isn’t a licensee of the program providers. So they can do whatever they want, assuming it is legal (like allowing you to download shows from your TiVo for offline viewing). On the other hand, an outfit like DirecTV _is_ a programming licensee. If they offered a TiVo-like way to download shows, a programming source (let’s pick Disney, for example) might refuse to renew DirecTV’s access to Disney programming when the contract comes up for renewal. DirecTV does go out of their way to be annoying, though. Your DVR break? Tough luck - the replacement won’t have any of your programming, even if you are using _their_ external drive and connect it to the replacement unit. Each DVR has a unique encryption key. Far better to make it a per-account key (since DirecTV allows viewing from one DVR to another already). And don’t get me started on losing all of the series managers, one-off future recording, etc. - despite the DVR having an Internet connection, a phone line, and a USB port, DirecTV doesn’t provide any way of saving that data, either. Back on the subject of commercial skips, one way to detect some (but not all) commercials is to look at the audio bitstream. My stereo has a display on the front, and much of the programming I watch is AC3 5.1. A lot of the commercials are AC3 2.0. Another clue would be the loss of the captioning bitstream - a closed-captioned show will often have un-captioned commercials. That isn’t as reliable an indicator, though, as the captioning can “run behind” the voices on screen, particularly if it is being captioned live. ---
**Author:** ![jacobsta811](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jacobsta811/32/2893_2.png) [@jacobsta811](https://boards.straightdope.com/u/jacobsta811)\ **Post date:** [July 13, 2016, 11:55pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/45 "2016-07-13T23:55:31Z")
[https://www.mythtv.org/wiki/Commercial\_detection](https://www.mythtv.org/wiki/Commercial_detection) MythTV did a pretty good job skipping commercials when I ran the box. Used a blend of methods as detailed in the link above. It was really hard to get anything but antenna HDTV into mythtv for a long time so I stopped running it and just get the shows from Hulu or the websites instead now, but it definitely worked on the vast majority of shows. ---
**Author:** ![cochrane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cochrane/32/10441_2.png) [@cochrane](https://boards.straightdope.com/u/cochrane)\ **Post date:** [July 14, 2016, 12:07am UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/46 "2016-07-14T00:07:05Z")
> [@Slash1972](#): > > Having a flunky (spouse or child) change the channel WAS a terribly useful system for most people before remote controls were invented 😃 > > I just want to win the nickel 🙂 Yup. When I was a kid, I was Dad’s “remote control” since I usually lay on the floor in front of the TV. 🙂 ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [July 14, 2016, 2:10pm UTC](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733/47 "2016-07-14T14:10:22Z")
> [@jacobsta811](#): > > [Commercial detection - MythTV Official Wiki](https://www.mythtv.org/wiki/Commercial_detection) > > MythTV did a pretty good job skipping commercials when I ran the box. Used a blend of methods as detailed in the link above. It was really hard to get anything but antenna HDTV into mythtv for a long time so I stopped running it and just get the shows from Hulu or the websites instead now, but it definitely worked on the vast majority of shows. …on OTA broadcast. Broadcasters are still held to stricter technical standards and tend to conform to “old ways” in cutting between program and commercial, so it’s likely the majority of the commercial breaks you caught had black-frame separation. I’d guess that the technique would work reasonably well on OTA channels anywhere in the US, barring a few indies run by chimpanzees. But we’re talking mostly about cable here, which is a whole 'nother ball game. Like you, I zap commercials by paying Hulu a whole $3 a month. [Previous page](https://boards.straightdope.com/t/why-no-ad-blocking-for-cable-tv/759733.md?page=2)