SageTV Community  

Go Back   SageTV Community > General Discussion > General Discussion
Forum Rules FAQs Community Downloads Today's Posts Search

Notices

General Discussion General discussion about SageTV and related companies, products, and technologies.

Reply
 
Thread Tools Search this Thread Display Modes
  #21  
Old 07-13-2007, 09:36 AM
bcjenkins bcjenkins is offline
SageTVaholic
 
Join Date: Jan 2006
Posts: 3,764
If I were running a cable company..

I would un-encrypt QAM for the extended basic tier of channels and let users pull them in with service like they do today by hooking up to the QAM tuner in their spiffy digital TVs.

B
Reply With Quote
  #22  
Old 07-13-2007, 10:02 AM
wtsitmn's Avatar
wtsitmn wtsitmn is offline
Sage User
 
Join Date: May 2006
Posts: 63
Cable vs OTA

It's important to keep in mind that the digital files received OTA are not the same as those received by cable or satellite. A friend of mine was surprised when he saw the quality of my OTA HD programs. He recently upgraded to HD on his satellite subscription, thinking he would be getting the best quality HD picture available.

For those people with high quality 50+" HD sets, the difference is quite noticeable. Unfortunately, the file size of OTA programming is also larger than satellite or cable. But that's the price one pays for quality.
Reply With Quote
  #23  
Old 07-13-2007, 10:10 AM
toricred's Avatar
toricred toricred is offline
Sage Icon
 
Join Date: Jan 2006
Location: Northern New Mexico
Posts: 1,729
That's true, but there is a significantly limited content available OTA. In addition, satellite digital is not necessarily HD and would be better to compare to SD in most cases. The HD on satellite is nowhere near the quality of HD OTA, but nobody is forcing you to change to HD, only digital.
Reply With Quote
  #24  
Old 07-13-2007, 10:29 AM
wtsitmn's Avatar
wtsitmn wtsitmn is offline
Sage User
 
Join Date: May 2006
Posts: 63
Quote:
If today a person has no interest in recording HD and tomorrow starts receiving a digital signal only though their cable box it will have virtually no impact on them in comparison to their SD analog recording. A digital or analog SD recording is also trying to convey. And they could actually use the svideo out of their digital cable box to the svideo in of their analog tuner and continue recording their shows in SD.

I agree that when using satellite or cable, the difference in file size between SD and DTV won’t vary much, if at all. However, OTA isn’t the same. SD and HD files are about the same size OTA—big! So if a person is using an antenna, s/he will notice a significant difference when changing from analog to digital tuners. And as I understand it, that’s the subject of this thread.

I myself enjoy the much higher quality of OTA broadcasts, especially with giant screen HD. Furthermore, when we switched from DirecTV to an antenna, I thought everyone would miss the selection available on satellite. Surprisingly that was not how it turned out. Without satellite, the family has more TV recorded than they have time to watch. And of course it’s a whole lot cheaper. (free, that is!) And for those of you who would miss reruns and movies, there’s always a $20 subscription to Blockbuster or Netflix. That about covers it for most everyone except maybe the sports and news junkies.

And for those wondering why I ditched satellite TiVo and DirecTV for an antenna, the answer is simple. So I could afford a new giant screen HDTV. The high quality recordings were just a nice bonus.

Last edited by wtsitmn; 07-13-2007 at 11:04 AM.
Reply With Quote
  #25  
Old 07-13-2007, 10:34 AM
wtsitmn's Avatar
wtsitmn wtsitmn is offline
Sage User
 
Join Date: May 2006
Posts: 63
Quote:
Originally Posted by toricred View Post
That's true, but there is a significantly limited content available OTA. In addition, satellite digital is not necessarily HD and would be better to compare to SD in most cases. The HD on satellite is nowhere near the quality of HD OTA, but nobody is forcing you to change to HD, only digital.
Sounds to me like you're mixing apples and oranges. The only people being forced to change to digital broadcasts are OTA users. Satellite and Cable customers won't notice a thing. And when an antenna user switches from analog to digital, they have no choice but to receive programs as they're broadcast. With so many shows now in HD, people are forced to get them that way whether they want to or not.

This brings up another issue I've been wondering about. Since all OTA HD broadcasts are 16x9, will owners of older 4x3 sets get black bars on the top and bottom of their screens?

Last edited by wtsitmn; 07-13-2007 at 11:15 AM.
Reply With Quote
  #26  
Old 07-13-2007, 12:04 PM
GKusnick's Avatar
GKusnick GKusnick is offline
SageTVaholic
 
Join Date: Dec 2005
Posts: 5,083
It's true that a lot of OTA primetime programming is HD, so those recordings will be bigger than analog users are accustomed to, by about the factor of three I cited earlier, i.e. 6-8 GB/hr.

However it's also true, at least in my area, that some digital OTA stations broadcast some of their programming in SD, and these recordings are comparable in size to what I used to record with my analog tuners, i.e. about 2-3 GB/hr. I give the actual numbers, now and in my previous post, in the spirit of being helpful rather than pissy.

I also think it helps, when someone says "your existing system can't handle HD", to post counterexamples of systems that can and do handle it with fairly run-of-the-mill components. And again, I gave the numbers to back that up. Sorry if that came off as "mine's bigger" to you; that wasn't the intention.

If you want specific advice on how to troubleshoot your system, the first step (as I tried to imply earlier, apparently not very successfully) is to figure out where the bottleneck actually is. Windows 2000 and XP include performance monitoring tools that should help you narrow it down to disk, network, CPU, or what have you. My guess, based on the numbers and on my own experience, is that it's not your disk.
__________________
-- Greg
Reply With Quote
  #27  
Old 07-13-2007, 01:24 PM
wtsitmn's Avatar
wtsitmn wtsitmn is offline
Sage User
 
Join Date: May 2006
Posts: 63
2x2x2=8

Isn't that odd. When I recorded programs using my old analog tuner, they took just under 2GB/hr with a Sage setting of "Great". With a digital tuner, the very same programs used just under 4GB/hr. I know this because I used to record many episodes of Cheers and noticed the files were really hogging the disk space when recorded with my new digital tuner. Then I switched back to using the analog tuner to record those programs, and the size of the files was cut in half.

The other point I was making was that someone who is accustomed to recording a program which is broadcast in HD will find the size of the recording to be at least 4 times larger when they stop using an analog tuner because they will be forced into recording the HD version, which runs about 8GB/hr.

So when I first said DTV files were humungous, that's what I was talking about. Yes, HD is twice the size of SD, but SD is at least twice the size of analog. So with many new programs now being broadcast in HD, there is much to consider when converting from analog to digital tuners. At least when using an antenna.

BTW Greg, would you care to include your computer specs in your profile? Then I and others would have a basis for comparison.

Thanks for your help.

Last edited by wtsitmn; 07-13-2007 at 01:35 PM.
Reply With Quote
  #28  
Old 07-13-2007, 02:18 PM
GKusnick's Avatar
GKusnick GKusnick is offline
SageTVaholic
 
Join Date: Dec 2005
Posts: 5,083
So we've determined that DTV file sizes vary depending on the program and the broadcaster, which isn't too surprising. A factor of two either way isn't a big deal for me, since I generally delete recordings after watching them. For archival purposes, Sage V6 has built-in conversions that let you compress things down to smaller files sizes if you like.

Here's another current thread specifically about HD system specs (including mine):

http://forums.sagetv.com/forums/showthread.php?t=26297

There are also a number of current threads about HD troubleshooting.
__________________
-- Greg
Reply With Quote
  #29  
Old 07-13-2007, 02:36 PM
wtsitmn's Avatar
wtsitmn wtsitmn is offline
Sage User
 
Join Date: May 2006
Posts: 63
Thanks

Thanks Greg.

I see you have a rather robust system, to say the least. Clearly superior to what I'm using now. No wonder you're not experiencing performance issues. The 1000MHz FSB alone should help your throughput considerably. That added to your dual core 64 bit processor would significantly outperform older machines.

BTW, in all this discussion perhaps I didn't make clear that when my system has problems is when it's simultanously recording three HD programs and playing another HD program. Have you ever tried doing this particular combination? It would be much more stressful on a system than recording SD 4GB/hr programming. But with your particular configuration you may have no trouble.
Reply With Quote
  #30  
Old 07-13-2007, 03:13 PM
stanger89's Avatar
stanger89 stanger89 is offline
SageTVaholic
 
Join Date: May 2003
Location: Marion, IA
Posts: 15,188
Quote:
Originally Posted by wtsitmn View Post
I agree that when using satellite or cable, the difference in file size between SD and DTV won’t vary much, if at all.


Whoah there, back up a bit, you're mixing terminology there and that can lead to confusion.

There are basically two "format" categories, SD (480i/525i) and HD (720p+). In the strictest technical sense, these are independent of the transmission scheme. Ie they can be analog or digital (I believe Japan had analog "HiVision" for a while).

Separately, there are two categories of transmission scheme, Analog (NTSC/PAL) or Digital (ATSC, Digital Cable, Digital Satellite). But the video format is independent of transmission scheme.

Now in practice, if we're talking analog here, we mean SD because nobody broadcasts analog HD and there are no tuners available. When we're talking digital, we have to be careful because it can be either.

Now regarding file sizes for "digital" Cable/Sat, that's not a simple answer as you make out. For digital SD, file sizes will generally be quite small, usually on the order of 1GB/hr, maybe 1.5GB/hr. For Digital HD from Cable/Sat it will be significantly larger, but probably only on the order of 5-6GB/hr*.

What you should note is that you can't use size to directly compare quality between our analog recorders and the cable/sat digital feeds. Why? Because the cable/sat companies have multi-thousand-dollar realtime encoders that are far more efficient than even the best hardware PC encoders. You'll find that the cable/sat companies can get roughly the same quality at probably 1/2-1/3 the size our encoders can.

*With the move to MPEG-4 HD, HD from Satellite will proably be on the order of 2-3GB/hr due the significantly higher encoding efficiency of the codec+encoder.

Quote:
However, OTA isn’t the same. SD and HD files are about the same size OTA—big!
The same thing is true of SD, except since individual operators are given fixed bandwidth, there is less motivation to reduce the bandwidth used so compression is generally lighter on OTA than on Cable or Satellite. The theoretical size of an OTA capture is just under 9GB/hr based on the 19.4Mbps bandwidth allotted. However when you actually go look into it, you'll find that most providers multicast HD and SD channels, and that the HD ones range in the area of 12-16Mbps or 6-8GB/hr and the SD ones are again in the 1-2GB/hr area.

Again, note that size depends on format (HD or SD).

Now, the complication with "HD" broadcasts. Most OTA channels broadcast their HD sub as HD all the time, regardless of whether the source content is HD or not. They will upconvert the majority of their non-primetime programming.

To summarize, size is tied mostly to broadcast format (HD or SD), that will determine the general magnitude of the size, though there is a general tendency for OTA to be slightly larger than Cable/Sat due to the later's bandwidth restrictions.

But you just can't say OTA is bigger than Digital Cable/Sat.

Quote:
So if a person is using an antenna, s/he will notice a significant difference when changing from analog to digital tuners.
Size will probably double when recording HD broadcasts, maybe triple.

Quote:
And as I understand it, that’s the subject of this thread.
Quote:

I myself enjoy the much higher quality of OTA broadcasts, especially with giant screen HD.


Realize that most content is still not HD, and that satellite, while digital (and generally better than NTSC), is not usually HD, so of course OTA HD will be better.

Quote:
Furthermore, when we switched from DirecTV to an antenna, I thought everyone would miss the selection available on satellite. Surprisingly that was not how it turned out. Without satellite, the family has more TV recorded than they have time to watch.
That's definitely a individual determination. I know I rarely use my ATSC tuner, there's just nothing on the big networks I want to watch.

Quote:
And of course it’s a whole lot cheaper. (free, that is!) And for those of you who would miss reruns and movies, there’s always a $20 subscription to Blockbuster or Netflix. That about covers it for most everyone except maybe the sports and news junkies.
Quote:

And for those wondering why I ditched satellite TiVo and DirecTV for an antenna, the answer is simple. So I could afford a new giant screen HDTV. The high quality recordings were just a nice bonus.
I kind of wish I could do that, but like I said, 90% of my favorites are not on broadcast TV, many aren't out in DVD, and most of the remaining ones are far behind broadcast as far as DVD releases go.

Quote:
Sounds to me like you're mixing apples and oranges. The only people being forced to change to digital broadcasts are OTA users. Satellite and Cable customers won't notice a thing.
OTA is the only thing being forced to abandon analog, and no, Cable users won't notice anything right away. However cable is rapidly pushing to go all digital as dropping their analog service will free up a LOT of bandwidth (you can cram 6-8 digital SD channels in the space of one analog SD channel).

Cable companies are also moving to "Switched Digital" to free up more bandwidth as well. As analog "dies". I think the cable companies are going to be bolder and bolder WRT forcing STBs on people. Of course as they do it, they'll risk losing a significant number to satellite as I think many shy away from Sat due to the STB requirement.

As for sat users, well, nothing will change as Sat is already all digital and everybody already needs boxes.

Quote:
And when an antenna user switches from analog to digital, they have no choice but to receive programs as they're broadcast. With so many shows now in HD, people are forced to get them that way whether they want to or not.
Some channels simulcast in HD and SD so people could choose to receive/record the SD version instead.

Quote:
This brings up another issue I've been wondering about. Since all OTA HD broadcasts are 16x9, will owners of older 4x3 sets get black bars on the top and bottom of their screens?
Yes they will.

Quote:
wtsitmn Isn't that odd. When I recorded programs using my old analog tuner, they took just under 2GB/hr with a Sage setting of "Great". With a digital tuner, the very same programs used just under 4GB/hr. I know this because I used to record many episodes of Cheers and noticed the files were really hogging the disk space when recorded with my new digital tuner. Then I switched back to using the analog tuner to record those programs, and the size of the files was cut in half.

The other point I was making was that someone who is accustomed to recording a program which is broadcast in HD will find the size of the recording to be at least 4 times larger when they stop using an analog tuner because they will be forced into recording the HD version, which runs about 8GB/hr.


As you noted in the previous paragraph, the difference is closer to 2x ratio. And that depends on what analog quality setting you were using. Many record at closer to 3GB/hr.

Quote:
So when I first said DTV files were humungous, that's what I was talking about. Yes, HD is twice the size of SD, but SD is at least twice the size of analog.


No, actually digital SD, if actually broadcast in SD, is on the order of 1/2 to 1/3 the size of analog SD. When I've recorded SD off digital cable or Dish, they end up right about 1GB/hr, sometimes a bit less, sometimes a bit more. They're actually so small, that for some of the ones I've pondered archiving, I'm having a tough time justifying the effort to compress them as they'd only be 30% smaller.

The Cheers example you use above is almost certainly of upconverted SD. So what you're recording is actually an HD broadcast, HD file, but the content is SD sourced.
Reply With Quote
  #31  
Old 07-19-2007, 08:09 AM
tawd1992 tawd1992 is offline
Sage User
 
Join Date: Apr 2006
Posts: 56
Stanger89 - Thanks for the explanation, that answered a lot of my questions.
I always wondered why some HD channels looked so bad, now I know it's because they are upconverted & not true HD. You're also right on that the cable company's equipment is far superior to anything we can get. I rented a DVR from the cable company about 2 years ago & I couldn't believe not only how much better the pq was of the analog channels, but that the recordings were only 1GB/hr. I really don't like paying a cable tax (renting a stb), but the quality is so much better I'm tempted to give in.

BTW, do you own an '89 Stang?
Reply With Quote
  #32  
Old 07-19-2007, 09:59 AM
stanger89's Avatar
stanger89 stanger89 is offline
SageTVaholic
 
Join Date: May 2003
Location: Marion, IA
Posts: 15,188
Quote:
Originally Posted by tawd1992 View Post
Stanger89 - Thanks for the explanation, that answered a lot of my questions.
I always wondered why some HD channels looked so bad, now I know it's because they are upconverted & not true HD. You're also right on that the cable company's equipment is far superior to anything we can get. I rented a DVR from the cable company about 2 years ago & I couldn't believe not only how much better the pq was of the analog channels, but that the recordings were only 1GB/hr.
Analog channels shouldn't be appreciably different, especially not in a DVR. They're probably using encoders on par with what we have. What I was talking about was the broadcast encoders the providers use to encode the channels they broadcast digitally.

Quote:
I really don't like paying a cable tax (renting a stb), but the quality is so much better I'm tempted to give in.
It's quite likely it's a playback difference you're seeing, not a recording difference, many think the SD output of CE devices is better than PC playback of SD.

Quote:
BTW, do you own an '89 Stang?
GT, 60k on it about.
Reply With Quote
  #33  
Old 07-19-2007, 10:18 AM
dotheDVDeed dotheDVDeed is offline
Sage Advanced User
 
Join Date: Mar 2007
Posts: 84
Quote:
Originally Posted by stanger89 View Post
As for sat users, well, nothing will change
..snip

Well not quite. Sats going through a big change as well. To also increase bandwidth (more HD channels) they are switching over from MPEG2 to MPEG4. It means subscribers will have get new dishes and new equipment to receive these newly offered HD channels.

TIM
Reply With Quote
  #34  
Old 07-24-2007, 07:44 PM
tipstir tipstir is offline
Sage Advanced User
 
Join Date: Jan 2006
Posts: 82
Wink

For me it's going to change the way I get the cabletv now by the end of the year that project will be finish. All digital no more analog... Does SAGETV 5.9x support HVR1600 if I would need to buy one since 4x analog PVR150s won't work and I need to get my media on 5x MediaMVP.
Reply With Quote
  #35  
Old 07-24-2007, 08:54 PM
Ryokurin's Avatar
Ryokurin Ryokurin is offline
Sage Aficionado
 
Join Date: May 2004
Posts: 455
Send a message via ICQ to Ryokurin Send a message via AIM to Ryokurin Send a message via Yahoo to Ryokurin
The biggest thing to remember is that the digital change over date only applies to over the air broadcasts. Cable does not have to change a thing and in most cases wont. When more HD channels come on line I expect them to require cable boxes since it won't be feasible to do it all over analog but hopefully by then solutions similar to HD homeruns only internal will be available.
Reply With Quote
  #36  
Old 07-24-2007, 11:13 PM
ke6guj ke6guj is offline
Sage Icon
 
Join Date: Jan 2005
Posts: 2,355
Quote:
Originally Posted by tipstir View Post
Does SAGETV 5.9x support HVR1600 if I would need to buy one since 4x analog PVR150s won't work and I need to get my media on 5x MediaMVP.
the HVR1600 was not officially supported by Sage until V6.1
Quote:
The main updates to V6.1 over V6.0 are as follows:

Lots of Bug Fixes
New Logo + UI Enhancements
YouTube Videos
DVB-T/QAM on Linux
New Cards on Windows: Hauppauge HVR-1600 (supports dual ATSC + NTSC)
IIRC, the card may have worked in V6, but with only single tuner support. No idea on V5
__________________
- Jack
__________________________________________
Server: AMD Phenom 9750, 2GB RAM, 2 Hauppauge PVR500, 1 Firewired DCT6200, 1 HDHomerun tuning 2 QAM channels, Vizio 37" HDTV LCD, 1 USB-UIRT

Clients: 1 MediaMVP, 1 Placeshifter Client, & 1 SageTV Client.
Reply With Quote
  #37  
Old 07-25-2007, 08:00 AM
stanger89's Avatar
stanger89 stanger89 is offline
SageTVaholic
 
Join Date: May 2003
Location: Marion, IA
Posts: 15,188
Quote:
Originally Posted by Ryokurin View Post
The biggest thing to remember is that the digital change over date only applies to over the air broadcasts. Cable does not have to change a thing and in most cases wont.
Actually they will. No they don't have to, but going to digital frees lots of bandwidth, and bandwidth is money. The second they can abandon analog, and it's "wasted" bandwidth they will.

Remember, the bandwidth required by one SD analog channel can carry at least 2 digital HD channels, or upwards of 16 digital SD channels.

Oh, and as for analog HD, well, that would take probably 6 analog channels worth of bandwidth, and there's no standard for analog HD broadcast.
Reply With Quote
  #38  
Old 07-25-2007, 09:58 AM
lobosrul's Avatar
lobosrul lobosrul is offline
Sage Expert
 
Join Date: Aug 2005
Location: Albuquerque, NM
Posts: 573
Remember, you will still be able to use an analog tuner from a cable box (via S-video). The digital switch over applies from the cable co to your house.
Reply With Quote
  #39  
Old 07-25-2007, 01:22 PM
stanger89's Avatar
stanger89 stanger89 is offline
SageTVaholic
 
Join Date: May 2003
Location: Marion, IA
Posts: 15,188
Quote:
Originally Posted by lobosrul View Post
Remember, you will still be able to use an analog tuner from a cable box (via S-video).
As you will from satellite, or even from an ATSC tuner box (not that you'd want to do it for the later).

Quote:
The digital switch over applies from the cable co to your house.
As far as the law goes, the mandatory switch only applies to local broadcast (OTA). Cable can still use analog to your house, and probably will for some time. But there's definitely motivation there for them to convert everyone to digital.

There is perhaps, a bit of hope though, that the current "clear" analog channels with transition to "clear" digital channels, maintaining the current status quo of not needing to rent anything to receive the "basic" or "expanded basic" tier. Slim hope of that though.
Reply With Quote
  #40  
Old 07-26-2007, 11:34 AM
lobosrul's Avatar
lobosrul lobosrul is offline
Sage Expert
 
Join Date: Aug 2005
Location: Albuquerque, NM
Posts: 573
Stanger, I was just trying to make the point that no one should be panicking that their analog tuners will suddenly become useless.

With h.264 encoding a cable co can cram about 3 times as many digital HD channels as analog SD. So there's the motivation right there. If cable doesnt move to all digital there's no way theyd be able to offer nearly as many HD chans as satellite.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Analog channel 44 not showing in guide? snoopy SageTV Software 1 07-13-2007 01:51 PM
Can HDHomeRun be used as standard analog tuner? LehighBri Hardware Support 1 04-18-2007 08:40 AM
My EPG Experience... Azam SageTV EPG Service 6 04-10-2007 10:21 AM
Prefer SD digital source over SD analog dwalton22 SageTV Software 5 02-21-2007 07:36 AM
Digital and analog tuners on one lineup? gmanning SageTV Software 1 12-24-2006 01:59 AM


All times are GMT -6. The time now is 01:01 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.
Copyright 2003-2005 SageTV, LLC. All rights reserved.