Dual tuner dvb-s2 on single CI slot? (1 Viewer)

[mm1352000]

Hi again babelfish

Well, that's about "decoding" the signal from a multiplexed signal on a carrier frequnecy. We are talking about decrypting allready "decoded" data and that IS something different, not?

No. "Decoding" in that context is synonymous for decrypting. "Multichannel decoding" is the ability to decrypt more than one encrypted channel from the same transponder using a single tuner and CAM.

Besides I suspect you had a spelling error when you said the DD tuner only decrypt one channel? I guess it should have been "decode"?

No I did not mean decode in the way that you use it. Each DD tuner can only "decrypt" one channel. There can be multiple tuners on a card and those tuners can share the CAM (so the CAM can decrypt multiple channels for multiple tuners). However, each tuner can only ask the CAM to decrypt one channel. With one card like a Cine S2 that has one CAM connected you can decrypt 2 channels because each tuner can decrypt one channel. However as I said earlier, the wiki is written from the perpective of a tuner, not a card or CAM.

Without blaming or mentioning anyone in particular, the team has traditionally used "card" instead of "tuner". I don't know whether that is a German -> English translation thing but I certainly found it very confusing and I do my best to clarify when I see it.

Besides the text you quote are aslo wrong when it assume one card = one tuner. Most or all DD tuner cards have two tuners and some can be linked together on the same "main board" increasing the mumber of possible tuners to 4 or 6 with SI connected (6 or 8 without an SI)

Of course this is true. However not all cards have multiple tuners. Therefore my opinion is that we should use the lowest unit - the tuner rather than the card - for comparison.

The wiki does not take this into consideration and use outdated asumptions.

Please be reasonable. The DD cards are very good, but you have to use fair measures to compare them with other cards. In my opinion it is fairer to compare tuner vs tuner not card vs card.

So, barly able to admitt that the description was plain wrong you choose to moan about those pointing it out.

I'm not trying to moan and I'm not barely able to admit that the description was wrong. I'm *very* sorry if I came across as rude. Honestly though, you and I seem to have a different perspective. I understand where you're coming from but I don't think you had understood my point: DD multidecrypt is not the same as the MediaPortal multichannel decoding (or "decryption" if you prefer that term) feature.

No I can't comment, No I can't submit changes. I have no rights for this with my common accout.

Up at the top of the wiki is a place to log in. I link it -->here<--. Are you sure you're not able to create an account?

And Finally, No i do not consider myself knowledgefull enough to start editing such documents as I there are lots of big holes in my knowledge here ( I would just make an arse out of my self by putting in plain wrong statements).

Fair enough. In fact I had already done a very big overhaul on the page when I posted. I hope you like it.

I do contribute other places quite a lot but never, ever do pull the "I do this for free so stop complaining and start contributing yourself"

That was not my intension so I'm sorry if I came across that way. My actual intension was to raise this in a place where it won't be "lost". Typically issues with the wiki are raised -->here<-- and comments about specific pages are made at the bottom those pages "inside" the wiki.

I suspect your spelling slipped again as I assume you are talking MP's ability to do multi decoding not decrypting? Just follwing the latest updates on the Wiki here.

For me decrypt == decode. Maybe that is where we have the misunderstanding?
I'd like to further clarify that the ability to view/record multiple free channels from a single transponder with a single tuner is a similar concept to "multichannel decoding", but it is not the same. I would not call viewing/recording of free (non-encrypted) channels decoding or decrypting. I guess you could say that the signal is simply "processed" by TsWriter/TsReader and then passed on to codecs etc. Again, maybe this is where there is a misunderstanding.

I thought this section decribed software AND hardware features? I find both features most relevant for the wiki. I gues the best solution could be to add a column in the table to add MTD ability?

The page describes hardware features. However MP/TV Server must include code that enables those features. Example: DiSEqC switching would not work at all without specific code for each manufacturer (like DD or Hauppauge).

The same is true for "multichannel decoding" - we have to add specific code for tuners that support it to get single tuners to decrypt multiple channels. Other software might not do that, but it could if they added similar code.

The same is *not* true for DD's MTD. There is no special code for MTD in TV Server. We tell the tuner driver to decrypt channels, but we don't have direct control over the CAM to manage the decrypt requests for all the tuners on the card (and connected via extensions). There is no way that we could add support for MTD to any other card/tuner unless we had the driver code for that card/tuner.

In other words, MTD is a DD feature and multichannel decoding is a TV Server feature.

Dedicated PVR's have had multi tuners connected to the same CI for years. Nothing new there. But we have been drooling

And quite rightly so!
It is a truly *great* feature... but it is not a TV Server feature, which is why it is not listed in the wiki.

Is that the only reason you supose FloppyDTV is popular?

No of course not. It was one of the first DVB-S2 tuners and has proved to be reasonably stable and reliable.

This feature were hardly known when I bought my card. The choise were easy as 9 of 10 recommended it. That's how most people choose low volume items like this: word of mouth.

Definitely - I choose things that I buy in the same way. However I think multichannel decoding was very attractive when MTD was not available. It is still valued highly by some people.

Even when I was informed about the multi decoding ability several people inisited that this was a miracle machine decoding and descrambling any channel on the same satelite and provider. Not a very limitied feature where only channels on the same channel were available.

I think it is all about your expectations and perspective. Until the DD cards came along it was literally not possible to get anything better than decrypting multiple channels on a single transponder. Surely that is better than only being able to decrypt one channel per CAM?

- You say that channels on the same transponder can be decoded/descrambeld at the same time.
I have allways assumed that Transponder = LNB. a Quad LNB would be A Quad transponder ( but in my terminology still one transponder). From what you say that doesn't make much sense. Is one transponder = one frequency (and possibly some Hor/Ver polarisation shit I never came around to check out)?

One transponder = one frequency.
Each transponder has a "bouquet" of channels.
Each LNB "receives" signal from a subset of the transponders available from a single satellite. Usually only one polarity + band is received at a time.

- I assume decoding is about getting a pure data signal off a polarized, multiplexed carrier frequnecy, is that right?

I guess it depends who you ask. As I said earlier, I treat "decode" the same as "decrypt". Also, I think of the ability to record/view multiple channels from a single transponder as different to "multichannel decoding". TV Server can use *any* DVB/ATSC tuner with a BDA driver to enable viewing/recording of multiple free channels. The same is not true for "multichannel decoding" - that is only supported by certain hardware... which is why it is specified on the supported cards page.

- Decrypting/descrambling, is that done in the actual tuner or are there dedicated circuits for this after the tuner and by lack of multituners systems it's become part of the tuner for simplicity?

I don't know much about tuner circuits and drivers - only the basics. First you have a tuner that tunes the frequency. Then you have a demodulator that takes the QPSK or 8PSK input signal (assuming a satellite tuner) and converts it to a digital MPEG 2 transport stream of 1's and 0's (binary). If a CAM is present, sometime after that the tuner driver or firmware will make all or part of the stream available to the CAM for decrypting... I think. There would certainly be dedicated circuits and driver code for that. The decrypting itself is done in the CAM - the CAM has specific-purpose software (firmware) for decrypting.

Sorry if the words seems harsh, that was no at all the intention. I started out just pointing out a more than obvious fact: The CI of the DD system does indeed decrypt more than one channel and the Wiki was plain wrong. I fail to see whats rude in that.

I think there has been a bit of a misunderstanding between you and I. It is completely unintentional from my side. Hopefully you have a better understanding of what I mean now. Yes the *CAM* can decrypt more than one channel, but each *tuner* can only decrypt one. TV Server is more focussed on tuners than CAMs or cards, which is why the wiki is written in the way that it is.

The only rude words I've seen so far is the

I must say that I get a little tired of hearing only complaints and requests. You do know that you can create an account and submit changes right? You can also comment on the bottom of each wiki page. I think either of those options would be more helpful.

Again I'm very sorry if you feel that I was being rude. My intention was:
1. To make sure that you are aware that there are better places to raise issues about the wiki content.
2. To let you know that there are ways to contribute to the wiki.

:sorry:

First of all I obviously can't neither comment or contribute as I don't have the access rights...

Hopefully you can now sign up for an account with the link I gave earlier.

...and secondly, getting barked at for pointing out obvious errors is just about as smart as yelling at alpha and beta testers reporting bugs. So pardon me, but the harsh words didn't start with me.

While doing things for free and being helpful is admirable it does not free one from neither making mistakes nor accepting faults. Being those faults are your own or others.

I fully accepted that the comment in the row was misleading, however I stand by my opinion that the description of the feature was accurate. Further, I spent 2-3 hours updating the page and I added a specific comment about MTD to the description of the multichannel decoding feature.

mm go out of his way to make me look like the rude and naughty one using all kind of irelevant arguments for a "defense" no one called for.

I really take exception to this comment. I hope you can see from this post that I have made a big effort to be polite, explain myself in full, answer your questions... I don't know what more I could do given the circumstances.

I don't know who wrote the faulty words regarding the CI but it is a fact that I've seen those same words repeated in other forums, arguing the lack of multi channel decrypting by the DD system. They also refered to the Wiki and with a "NO" in Multi Channel Decoding anyone but the specialists would assume only one channel could be decrypted and streamed from any DD system.

The misunderstanding is unfortunate but surely you can accept that it was not intentional? I have moved as quickly as I could to clarify...

The fact is that several installations run MP with no less than four simultaniously streaming channels, all from different frequencies and all from scrambeled channels. That's why I find the Wiki documentation to be of somewhat importance as this is the first system that HTPC builders can use without multiple code-cards or illegal card sharing but the documentation go a long way in trying to prove the opposite.

I think part of the problem is actually DD's documentation. I find their website *extremely* confusing. I don't say that our wiki is or was perfect and blameless - the comment *was* confusing - but I do say that it is DD's responsibility to explain *their* feature in a way that as many people as possible can understand.

A lot of users of MP tv-server are tied down with some kind of encryption systems and I feel, hell, I KNOW that a small note at the bottom is something most will miss or just add to the confusion, and mm will be stuck patiently explaining what team-MedaiPortal consider to be multi-deCoding/deCrypting/deScrambling.

We do the best we can. We're not actively trying to spread misinformation in any way - I hope you understand that. At the end of the day though, it is not our responsibility to explain a feature of somebody else's product. It is the responsibility of the manufacturer. If you have any suggestions about how I can improve the wording of the feature description then I'm very open to it. One thing I am not going to do though is make our wiki a place that advertises certain cards.

The significance and difference between multiChannelDecoding and MultiChannelDecrypting is not at all obvious and leaving it as it is in the Wiki, even after the later adjustments is not informing very well on the DD cards abilitys, allthough it does clear up the difference between multi-decoding and decrypting abilities. The problem, I feel, is that the definition of multiChannelDecoding is hard to get. With the entry of multi tuner cards those there seems to be a few definitions that need a rewrite.

Again, it is not our job to inform about the DD card abilities. *Any* software that supports decrypting with a DD card also supports MTD with DD cards.

mm

 

[DjeC64]

to come back to original topic of the post. I continued my investigation there:
https://forum.team-mediaportal.com/...i-does-not-work-102198/index2.html#post818379