HDHomeRun - Dual ATSC or QAM to Ethernet Box - Page 2

Bob,
None of the wireless protocals support streaming HD video, not enough bandwidth. The only option is to buy pre cert 802.11n gear. The downside is that you need a PCMCIA card for your laptop as the internal wireless chip is only b/g compatible. Your problem is well documented and tested many times 802.11g is not robust enough for you useage.
HTH,
GeoffQ

GeoffQ,

How do you explain the periods of time when I can a rock solid image over wireless? Those are possibly the times when my wireless gets 5 of 5 bars. When I get 3 of 5 bars, the picture often breaks up. Once I figure out the quality of signal problem, I'll verify your premise.

Bob.

if you are running an 802.11G or super-G (54M or 108M), it is certainly POSSIBLE to support HD....however, you must have a very strong signal all the time to do so.
if you assume overhead is about 50%, 802.11G transports 27M of traffic if it has a high enough signal to noise ratio.........which is possible if you are very close with few obstructions.

otherwise, don't count on it

if you have some of the 802.11N or even pre-N, you have a bit more margin but propagation can still be problematic.

Bob,

People don't realize how little of the advertised bandwidth people get with wireless technologies and how quickly the performance drops off with range/obstructions/and interference.

For example, I have a Netgear 108G which bonds two G channels together (advertised as 108Mb/sec). In my bedroom (~30f, 1 floor away), I'm lucky if I can get 1-2Mb/sec.

It was marginal streaming standard def.

I've actually just purchased a D-Link Xtreme N and am going to try it out. I suspect much better results.

In general, the D-Link Rangebooster & Xtreme N and the Belkin Pre-N have been reported to have much better range and much better bandwidth then previous wireless setups.

Keep in mind, they all require matching adapters (no mixing and matching) and for best results, you need to turn off older protocol compatibility.

Also, note that the HDHomerun is using UDP. UDP is a best effort protocol. It is nice that it has less overhead, but if packets are lost, it doesn't try to resend them. This would explain why you get picture impact when you have a less than optimal network connection.

I think when streaming of video over wireless you need to load the deck as much in your favor as possible. Get the best max-range N or pre-N router you can, matching N or pre-N card, and turn off backward compatibility.

Good luck!

-john

Finally, the "Aha!" moment. I now understand the remaining performance issues.

I now have all the ATSC and clear QAM channels working on wired Ethernet. Also, channels are either working properly or otherwise accounted for on 802.11g -- anywhere in the house.

There are several keys to understanding HDHomeRun's performance over WiFi.

1. It's not an issue of can or can't transmit HD over WiFi, it's an issue of data rate. I can receive all ATSC and some clear QAM channels without issue. These channels look and sound fabulous on my notebook. Breakups are rare even at the farthest reaches of the house. See above postings for my router and notebook configuraiton.

There are some clear QAM channels that I can't receive. That's due to their significantly higher data rate, higher than other channels. A key statistic in determining 802.11g-ability is shown in the Win32 client. It's labeled "Network Rate (pps)". If it's value is below 2,000pps (packets per second?), my 802.11g connection can handle it. At 2,500pps or above, the image starts to break up. I don't know the exact saturation point because there are no channels between 2,000pps and 2,500pps.

All ATSC channels in Chicago are below the magic 2,000pps so I'm able to obtain a solid image on all ATSC channels. The problematic QAM channels often sit at 3,600pps. For those, I get perhaps a >50% breakup with poor audio.

2. The HDHomeRun, client and VLC aren't very aware of each other. If I play a channel, then switch to a different network connection (different IP), the device continues to broadcast to the old IP. There seems to be no mechanism to say "hey, the client/player is disconnected, shut up". This causes the device to continue pumping packets needlessly, thus wasting bandwidth. It's enough of a problem that I put the HDHomeRun on a wireless router to segregate it from other traffic. That's not acceptable behavior. Connecting with a different IP doesn't necessarily stop the original broadcast. I believe this is because there can be separate streams for each of the RF ports. When this happens, your network, particularly a WiFi router, will start chocking from wayward or dual streams. I've learned to identify this issue because the device, client, or VLC start behaving erratically. Seems like the only fix is to power cycle the device.

My conclusion is that I'm delighted with the HDHomeRun's ability to reliably receive HD channels wirelessly anywhere in the house. Some QAM channels can only be received on a wired connection. The HDHomeRun software is far from robust. It needs to identify when the client is gone so it can shut up and not throttle bandwidth. It needs to have better error detection. Error processing troubles occur with weak signals (seems to have low QAM sensitivity), interrupted connections, or client shutdowns. Finally, there needs to be better documentation. There's misunderstandings about this device's abilities over wireless and general performance issues and expectations. Additional documentation and a well stocked FAQ would go a long way to assist troubleshooting.

Should you get an HDHomeRun? Well, at this time it's quirky. It's not consumer quality. It's for early adopters who have a need for an appliance that does ATSC/QAM over Ethernet. That would most definitely be me. I'm glad I have the device but look forward to improvements.

It's great that people are reporting qualified success with the HDhomerun. It has interested me since it came out, but I was afraid to put money at risk since 9thtee doesn't give any sort of money-back guarantee should the unit work, but unacceptably poorly.

However, the only reason I found this thread at all is I accidentally searched all forums, rather than the one I usually frequent: Digital Media Servers and Content Streamers. Another AVS forum that looks appropriate is the HDTV Reception Hardware. But HTPC's? Why?

TheKrell, I agree. It's not obvious which forum should handle HDHomeRun. A very similar device is the SlingBox. Both devices can only be viewed on a computer. That's the connection to this forum; a computer is essential to using the device. I'm not saying this is the correct forum, I'm giving the rational behind posting here.

Another thought, I'm not sure if the HDHomeRun should be classified any different than the DVICO HDTV USB device. They are both very similar devices except one interfaces to USB and the other to Ethernet.

I don't doubt that this is what people must be thinking but... I would hesitate to call PDAs or cell phones "a computer," however. (SlingPlayer Mobile is available for those platforms.) And in the case of the HDHomeRun, there are MythTV and VLC clients for embedded devices such as networked DVD players. At least that's what I recall, though I can't find said devices now that I'm looking for them. Must be getting old. One thing I like about the HDHomeRun is it's all digital. Correct me if I'm wrong, but it apperas that all versions of the Slingbox are basically A-to-D devices, so there is opportunity for signal degradation.

And now you've piqued my curiosity re: DVICO HDTV USB tuner.

Correct. There are no digital tuners in SlingBoxes. The resolution is VGA at best whereas the HDHomeRun is 1080i(?). The image quality is much better with a HDHomeRun. The HDHomeRun is too fast for Internet bandwidth. That is where the SlingBox shines. The SlingBox is an excellent example of a polished consumer device (router issues aside).

The DVICO HDTV USB device is a much more mature device but I do not find it consumer quality. It is quirky but less so than an HDHomeRun.

How is the recording quality? How is it compared to the Dvico? Is quality better under Myth or windows?

Recording quality should be the same across the board with digital tuners because they are not actually encoding anything. They simply capture the stream which is already encoded in MPEG2 (IIRC). What would affect quality would be your DEcoder, which is independent of these capture cards.

After reading up on this I am very intrigued by its potential with improved software support.

It's usable now, but with good MCE support (devs promise MCE support before the end of the year, the question is how complete that support will be as in QAM and guide recording support)

On their forum they have proposed a way to provide QAM support and in addition a poster there pointed the devs to some docs explaining the mechanism that CableCo's use to send channel mapping info to their STBs. If both these developments pan out in addition to the fact that is is a dual-tuner device the HDHomerun will be THE solution for an HD-HTPC.

I have two digital OTA tuners and believe me the quality is not the same. The HDWonder does not deal well with multipath where as the Fusion USB is much more tolerant. With the HDWonder I get a lot of stuttering, blocking and audio dropouts. With the Fusion I mostly don't have any of those problems.

I just installed an HDHomerun a few days ago. It was relatively easy to get up and running. I really like the fact that i can just connect it to my switch and then watch TV/HDTV on any of the computers connected to our network. All the computers on my network are running Windows XP Pro (SP2) or Vista. So I don't have any Linux/MythTV boxes. I currently only have the HDHomerun connected to my local cable service. I haven't had a chance to test OTA, but will do this after I get an antenna installed in my attic.

I have a few questions about channel assignments. Using VLC, the only channels that have a usable signal are 83, 84, 85, 86, 87, 88, 89, 90, 91, 104, 106 and 113. Each of these channels have several programs. So, for example with channel 86, there are 10 programs (numbers 1 - 10), which are actually ESPN Classic, A&E, ABC Family, AMCtv, History Channel, Fox News, Oxygen, Spike, Travel Channel, VH1 and the Cartoon Network. All the other channels also have up to 10 programs. There are other channels that have a signal, but they don't appear to have any program material that I can view. I'm assuming that they are the encrypted channels. Oh, and I can also get the cable services radio on channel 111, but that doesn't interest me.

To watch a show, I first use the 'HDHomeRun Config' applet to set the channel. then in VLC I can navigate to one of the ten programs listed under this channel. To switch to another channel/program combination, I have to toggle to 'HDHomeRun Config' applet and select another channel and then back to VLC to set the program number. Is there a better way? Obviously this is a little clumsy.

I tried the SageTV beta and it is even worse. I'm sure I haven't spent enough time with SageTV, because I read comments from many people who claim that it is a great program. The beta with HDHomeRun isn't very good. SageTV doesn't find any of the channels during a scan. And after manually adding a channel, you cannot get it to recognize any of the 'programs'.

So, my questions are...

Do all of the TV services use this Channel/Program method of assigning channels? Or, is this something unique to cable or my local cable provider (Charter)?


Am I missing something with VLC or SageTV with regard to channel assignments?

Is there any way to record broadcasts using VLC?

I will probably post these question in both the forums for HDHomeRun/SageTV beta and VLC.

He said RECORDING quality is the same.... reception/tuning issues are another ball of wax...

Gregg,

My cable service does the same as yours. Multiple sub-channels must be tuned in VLC, while regular channels are tuned in the client, it's inconvenient at best. HDHR client is a minimal implementation, certainly behind the DVICO HDTV tuner that I also have. However, I'm sure you will agree, it is presently very useful, wonderful video quality but needs considerable client improvement. It's no SlingBox, that's for sure.

I hope their client problems are circumvented by using MythTV, BeyondTV, Sage or whatever. It will take months for a better solution to emerge.

Exactly.

"So is there currently a way to record with this critter aside from MythTV? "

One could use TSReader to record the transport stream.
One could use Elecard Mpeg Player to play the network UDP stream (an alternative to vlc)

Bob-

I agree, it is very useful. I really like it that it is a network device. I think this is a much better solution than taking up a slot in the PC or connecting to a single machine via USB. The video quality is pretty good. Except that on many SD channels there is a band of noise flickering at the top of the screen. The band is very narrow, maybe only a few pixels wide, but it is still a little annoying. I wish there was some way to shift the image or mask it out.

Have you tried the SageTV beta for HDHomeRun? They supposedly have subchannels working, but I haven't been able to figure out how to get it working yet. I also haven't been able to get the channel scan to work for QAM256. It doesn't go beyond channel 100.

Gregg,

I also get the flickering at the top on some channels. It's another example of an immature product. It is automatically tuning QAM upto 135 here.

I have one of these, the client stuff will come in time. Some advantages to this box- 2 hd tuners, any combination of cable/air for both inputs, no drivers to deal with, box can be remotely located (put in basement/attic- where cable/antenna located), developers of the box seem to listen to suggestions on the forum and make firmware/software changes accordingly.

Its a little clunky to operate right now, but it looks like they will be able to make it work with various software- mythtv/beyondtv/mce/sage. I'm sure there's a bunch of smart people working on applications for this since there is no drivers to deal with and there's no secret to how it works.

I had a dvico fusion tuner- for qam recording, it was their application or nothing (ok, mythtv would work I guess), and was about 70% reliable for me.

I setup a batch file for recording/viewing, which takes takes several commandline arguments- 'view'/'record'/'view-record' channel name (ABC CBS etc) and if recording, the length in minutes to record. It simply starts vlc with appropriate options, tells hdhomerun to tune to channel, sets up filter so hdhomerun only transmits 1 program stream(very nice), tells hdhomerun which ip/port to broadcast to, then I have a simple little cscript that waits for recording time to finish and then sends keystrokes to vlc to stop/quit. I'm sure there's a better way, but this only took me a couple hours (including the usual batch file programming quirks I always have to re-live every time I do it).

I can see where someone could make a nice little stand-alone application for this. Integrate vlc (open source) or some other ts decoder/player with Titan TV (tvpi format no longer encrypted). There is nothing stopping anybody from doing this- no super secret drivers to deal with, just simple commands sent to a box on the network.

I can see many possibilities with this type of device.

That's not really an "example of an immature product" so much as it's your cable company broadcasting it that way figuring that the overscan on your tv will compensate for the band at the top. If you want to blame someone, blame your cable company.

It's not the cable company, but all TV sources. TVs by convention overscan, which is why that area of the frame is used for DATA (e.g., "Line 21" closed captions).

I see problems on top/bottom of picture on various sources- dish hd/cable/etc. Usually the overscan of a tv hides it. It's the originator of the signal that should get the blame. The hdhomerun has a 'simple' job of just decoding a digital stream- it doesn't know or care where the top/bottom/left/right of your screen is.

VLC has a crop filter- I haven't tried it, but that may help.

I'm not sure why the 'signal originators' need to screw up the edges on a digital signal- I can understand it with analog as there is no other 'location' to transmit data. I guess tv makers will have to continue to overscan (which they do) even though the signal is digital and the display is digital .The tv knows where the corners of the display are at- why do they have to throw away pixels. I guess because broadcasters can't be trusted around the edges.

curtvm, the additional benefits you mention are points well taken.

There is much work remaining to be done with the firmware and client software. Right now it is nowhere near consumer quality as in "Best Buy ready". It is a useful and interesting gadget for AVS type people. SlingMedia has set a high bar for their marketplace.

I see SiliconDust in a race between their efforts to mature their HDHR product and competitors entering the market with polished products. The market window for them is open now. Their success requires ramping up their technical skills as well as making the right business decisions. They need to be a very different company a year from now.

As far as the top twinkling scan line, it's not a matter of who is at fault, it's a matter of fixing the problem. It's all about the consumer experience. Who's at fault is a distraction from the real issue which is improving the consumer experience.

I think that there are going to be serious limitations under MCE. Silicondust plans on mapping the QAM channels to ATSC channels, since MCE doesn't support QAM. MCE guide information for ATSC channels is for OTA signals. Therefor, I suspect that one will only be able to receive QAM channels that have an OTA ATSC equivalent, i.e., major-network broadcasts. Using your digital cable guide data probably isn't going to work, because MCE will use the ATSC guide data for the virtual ATSC tuner. This doesn't bother me because most digital channels are encrypted anyway; at least I'll be able to receive major-network shows in DTV/HDTV if Slicondust can write a functional MCE driver.

Have you heard if they are working on compatibility with Vista's Media Center? From what I understand Media Center within Vista does support QAM. I've been running the HDHomeRun on a network with both XP and Vista and it works fine on either OS using the VLC player.

I agree this thing is not for the Best Buy shelves and probably never will be either, but that doesn't matter to me (i'm not a silicondust investor). We need more companies that target me, the oddball consumer.

If I can get clear qam to work with Vista MCE, that will make me happy. They may be the first ones to make it happen. In my case I just get the locals in the clear, but then at least I don't have to put up an antenna.

I recorded the USC football game last night (cable qam). Setup a batch file to record at 7pm for 210 minutes. Worked perfectly. If I can setup batch files to record cable qam, that means it has the right programming interface (in my opinion). If nothing else, at least I can 'program' this thing to record, and use MCE for playback.

I got the information on the virtual ATSC tuner from Silicondust's support/development forum. As far as I know, Vista only supports QAM in the context of an OCUR. The HDHomeRun can't emulate an OCUR because most cable systems are analog/digital hybrids and the HDHomeRun doesn't have an NTSC tuner. If it did, emulating an external OCUR without a CableCARD would be the best way to support it (Vista would be able to record all unencrypted QAM channels).