An Example system for 422 and HD and initial experiences

[mark_calgary]

A fairly long post. Feel free to comment on or critique it.


I thought it might be useful for those looking to put together DVB card based systems to share the details of my setup and some of my initial observations of the software I've used.

I spent a couple of months trying to determine what the minimum I would need for good 422 and HD signal decoding (mainly sports feeds). My goal was to end up with a system that would be slaved to my Pansat 2500 and output via DVI @ 1080i to my Sony HDTV.

Picking the hardware was the most difficult part. Obviously one wants to spend a little as possible and still guarantee good performance. There are so many options and one could always find someone who had problems with it.

For Hardware what I ended up with was this:

DVB card : Skystar 2 (rev 2.6D)
PC : MSI Neo 4F motherboard
AMD Athlon 64 3200+
1G PC3200 CL3 ram
Gigabyte nVidia 6600GT 128M, DVI, Svideo, Component out


Selection of the DVB card was not too difficult. I was torn between the Skystar 2 (popular in Europe) and the Twinhan 102g (popular here in NA). The European in me chose the Skystar. One of my issues was availability. At the time I could find no distributor locally for DVB cards, something that has changed recently (it is fairly obvious why), so I looked for a Canadian dealer. Unfortunately what I found was that I could order one from a supplier in Germany and have it cost 25% less, including shipping/taxes, than I could get it from a distributor in Canada!? Plus they took paypal which eliminated some US suppliers, including at least one sponsor of this site - they only take paypal or credit cards from US addresses ,very narrow minded in my opinion.

In general I think choosing between the two DVB cards is really a flip of the coin although I do notice that a few people in this forum are having support issues with the Twinhan. For me I think if this card fails the cost to send it back and the time spent waiting is not worth it. I would just buy a new one and now that I can get a 102g locally I would likely just get that (although still the same price as my shipped Skystar).

The selection of the PC was a bit more worrying. One can find people claiming they get great performance from a P4 2.4 to others having problems with P4 3.2. Just as important is the graphics card so, when I found a system that met my price point, had a graphics card that was designed to drive HDTV displays, and a processor that should be more than quick enough, I finally bought my system. The worry is that you never really know if it will all work until you see your first beautiful HD feed.



Software: I have only limited experience with the various DVB packages. I haven't had much time to play as I have a 1 year old daughter who recently learned how to walk and so takes up a lot of my free time (which I'm happy to give her). I have not done much in the way of tinkering with graphs and options yet so what I report here should be taken with a grain of salt or two.

Packages that I've tried are:

DVBViewer Technisat Edition - obviously comes with the card and I used it for my initial setup just to get things working. This version does not do 422 but does do HD. Works well but has an annoying error mesage that pops up when you can't lock a signal. Looks like it's designed for those having a fixed channel list and seemed clumsy to add channels or enter a wildfeed freq and symbol rate. Perhaps if I used it more I might be able to figure it out. But with no 422 I'm not interested in pursuing it.

ProgDVB (free)- a popular program, lots of people like it and I may try and spend some more time getting used to it. I find the user interface a bit clumsy and the program seems to be unrefined (but it's free....). Sometimes video does not come up and others the user interface doesn't respond for a few seconds. Initially I tried it out on a p4 1.7 with an SD signal and when I tried to stream over the network it brought the machine to its knees. I have not yet started playing with graphs but so far I've used it to play 422 and HD smoothly.

MTheatre ($40) - I really like the user interface. Seems very easy to add new sats/transponders. Seem to be some processor usage issues though. This morning it decided peg the processor at 100% cpu when I started it up on an SD channel (BVN-TV on IA5). I'll give a few examples of processor usage below.

TSReader($99)/VLC (free) - great combination. No screwing around with graphs. This seems to be a good combination for feed viewing but not as good for regular channels you might watch (i.e. my wife may not be able to operate it). I really like VLC a lot as it is also perfect for streaming, transcoding, and viewing on other machines on our mixed network. I may even try some low bitrate streaming over the internet to my work.

I've used VLC as a local viewer for MyTheatre as well.

Here are some processor usage values I've had for different stream types on MyTheatre and TSReader/VLC. Note that I haven't played with graphs or configurations so have lots of investigation to do.

Soon I will choose between purchasing MyTheatre or TSReader. I have some playing to do yet though. I also have yet to check out Alt-DVB and RitzDVB.

TSReader/VLC: HD (sports 1080i) 30%, 422 (sports) 20%, 420 5-10% (non sport).
MyTheatre(video off)/VLC: HD not tried, 422 20%, 420 5-10%.
MyTheatre(Video on): HD 80%!!!, 422 30%, 420 10-20%
VLC playback of MyTheatre recorded HD: 30%

All viewed fullscreen. HD is wonderful.....

I have not looked at processor usage on ProgDVB. Obviously there are some configuration issues with MyTheatre I will need to sort out.

In general I'm very happy with the performance of this system.

I hope all this info is of use to someone. I've certiainly learned lots from reading the posts of others.

 

[vj9999]

Very nicely summarized. TSReader/VLC is my preffered choice. SInce i consider this more as a hobby than for casual viewing, all the extra info you ge with TSReader is added bonus. Also Rod H. has always been great with supporting TSReader and releasing updates to clients. Probably the best $99 I ever spent on a piece of software.

Plus added bonus is ability to stream the video directly to Roku and avoid any video processing on the computer.

 

[digiblur]

On some HD broadcasts I was recording them and then letting MyHD play them back later. I decided to take the plunge and put in a AGP 6600GT DDR3-128 card. Love the card, uses the silent pipe technology so there's no added fan. I hooked up the DVI cable and it instantly detected the TV and few seconds later I had a desktop fit to my 57 inch screen. I fired up VLC and played a few 1080i broadcasts from MyHD and they played perfectly with around 40-50% CPU usage. I was stoked! That evening I moved the Twinhan card to the PC in hopes of Nascar being FTA the next day. Next thing I had to figure out was how to hook up all the dolby digital cables and other high def components to the TV & Receiver. XBox, Fortec, Dish811, MyHD, digital sound from QAM tuner in the TV, and now the DVI from the 6600GT.

I found the HD feed of the race the next day. I fired of TSReader and let it kick off VLC, but the video was choppy as all can be. VLC was hitting 100% usage. So I moved the Twinhan card back to other PC and decided to stream the HD across the network. The framerate picked up a bit but was still choppy. VLC was again at 100%. I have no problems streaming the PBS HD FTA feed across the network, I guess the PC can't handle the high bit rate of 26000 vs the 14000 or so. This is running on a P4/2.6ghz PC with 512mb or RAM.

I then tried the Twinhan back in the HTPC with MyTheatre with the elecard codecs for 4:2:2. The playback was a little better but the colors were all off. Not sure where to go at this point. With Xmas coming up I don't have the money to splurge for a new 3.2ghz PC, then I bet my AGP card don't fit on the new MB then I'm stuck buying another video card. This HD/FTA addiction is getting expensive!!

 

[mark_calgary]

Were you trying to watch a 4:2:2 HD feed on AMC-1 last Sunday?

That may require even more horsepower than the regular 4:2:0 HD. I was going to try and see if I could decode it with one of the many programs I've been trying out but I couldn't find the signal. My dish also wasn't very well aligned, something I spent a few hours doing on Sunday before I hibernate for the winter. Further investigation suggested that AMC-1 has a unique skew setting and I have no wish to change the skew on my motorized dish. I may have to mount a second LNB next to my primary one with the correct skew just for that satellite.

There are a couple HD hockey feeds I should be able to view this week. I'll play around while watching them and report on the performance I get. Perhaps you might try them out on your system and compare your performance with mine. One is on C band the other Ku.

In regards to my search for the "best" DVB program for me I've now come full circle.

I've found that TSReader performs poorly on weak signals. I would get heavy pixelation on a static HD image on G-11 C band tp7 but a perfect picture using DVBViewer (late last Saturday night/Sunday morning I fooled myself into thinking it might be a 4:2:2 HD signal - lack of sleep does that). MyTheatre sometimes now pegs the processor at 100% usage right after program launch. I can't justify purchasing it until it becomes more stable or I figure out what I'm doing wrong.... So I have been looking at DVBViewer again. Today I purchased a license for the "Pro" version (15 Euro) which has much more funtionality than the Technisat edition and will try and get 422 up and running on it tonight. It already seems to do HD quite well and is what I've been mostly using to view HD. It had the second best UI of the programs I tried.

 

[digiblur]

Were you trying to watch a 4:2:2 HD feed on AMC-1 last Sunday?

That may require even more horsepower than the regular 4:2:0 HD. I was going to try and see if I could decode it with one of the many programs I've been trying out but I couldn't find the signal. My dish also wasn't very well aligned, something I spent a few hours doing on Sunday before I hibernate for the winter. Further investigation suggested that AMC-1 has a unique skew setting and I have no wish to change the skew on my motorized dish. I may have to mount a second LNB next to my primary one with the correct skew just for that satellite.

There are a couple HD hockey feeds I should be able to view this week. I'll play around while watching them and report on the performance I get. Perhaps you might try them out on your system and compare your performance with mine. One is on C band the other Ku.

In regards to my search for the "best" DVB program for me I've now come full circle.

I've found that TSReader performs poorly on weak signals. I would get heavy pixelation on a static HD image on G-11 C band tp7 but a perfect picture using DVBViewer (late last Saturday night/Sunday morning I fooled myself into thinking it might be a 4:2:2 HD signal - lack of sleep does that). MyTheatre sometimes now pegs the processor at 100% usage right after program launch. I can't justify purchasing it until it becomes more stable or I figure out what I'm doing wrong.... So I have been looking at DVBViewer again. Today I purchased a license for the "Pro" version (15 Euro) which has much more funtionality than the Technisat edition and will try and get 422 up and running on it tonight. It already seems to do HD quite well and is what I've been mostly using to view HD. It had the second best UI of the programs I tried.

The only thing I've really tried HD besides the PBS HD feed was the 4:2:2 feed of Nascar. I don't think I have enough horsepower to handle these 25.000+ rates. I'll keep digging.

If I can get this thing nailed I'm going to look for one of those Creative USB sound cards. I've run out of room in the HTPC already so I need something external and preferably coaxial SPDIF out. Any ideas?

 

[mark_calgary]

Here are some results of my playing around last night.

I still haven't used Mytheatre again. It still has the 100% CPU utilization problem on startup. I may be able to fix it based on some reading over at the Mytheatre forum. There is also a new update to the 3.33 version that I currently have installed that is supposed to fix some CPU issues. Tonight I'll see if I can run it properly.

Last night I was using the HD OLN NHL game off of Galaxy 11 as a test. It is a ~17.5Mb/s 1920 by 1080i signal. (It is listed on Lyngsat so there should be no complaints about mentioning it in a public forum.... Later I scanned IA-8 and found a basketball game feed. HD is so much fun. I'm even watching sports I'm not interested in!!) My quality on G-11 was only 45% as I am crippled by a tree for this satellite. TSReader would not properly lock to it. The picture was heavily pixelated. DVBViewer, on the other hand, was rock solid - not a single dropout. I wonder if it is a TSreader problem with this particular signal as I have had 15% HD signals that TSreader could lock to with a viewable picture.

On DVBViewer there are a few options for video/audio decoders that I can easily play with so I flipped between them to see what effect on the CPU usage they had.

Forgive me if the names are not quite right. I'm going by memory.

Elecard 2.0 55-60%
Nero DVD 55-60%
Sonic Cinemaster 25-30%

I also recorded a few minutes and played it back through VLC - 50-60%

I did not play with the settings of the decoders so there is some optimization that is certainly possible.

One thing that did come to the forefront relates to deinterlacing and that may be your culprit. I noticed major interlacing artefacts on the Elecard, Nero, and VLC decoders but nothing on the Sonic. It may be that Sonic decoder handles the interlaced frames better or just differently than the others. The first thing that came to mind was that it was discarding half the frames. I would have to say that the picture was very smooth and crisp, even during fast action so I find that hard to believe. When I set the deinterlace option in VLC to discard, the artefacts went away but the action was not smooth and the CPU usage did not drop from 60%. As well the picture was not as crisp as the Sonic decoder.

I may work out how to change some of the settings of the Elecard and Nero decoders to see I can get them to operate any better.

My suggestion is that you try other decoders. I'm a bit surprised about the poor performance of VLC as that is the one that had the best CPU usage when I first got things running.