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A DVB-T tuner with hardware MPEG decoder


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Anyone knows a DVB-T card which has a MPEG2 hardware decoder on board?

Hi mjrasxhti,

As far as I know there is no DVB-t PCI device with an onboard hardware MPEG decoder.

I am not sure that such a device is really necessary (or even desirable) nowadays, as PC become more and more powerful software based decoders can handle the job very effectiverly, are cheaper and more flexible.

Cheers

Renura

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There are no DVB-T cards that do this. For a number of very good reasons. Transporting the mpeg2 encoded stream from the DVB-t card => PCI Bus => Main memory => CPU => AGP Bus => Video card (which can then decode it) is a lot more efficent in terms of PCI and AGP bus bandwidth utilization, not to mention memory buffer sizes etc.

As Renura has already said there are two main approaches these days. Decoding on the video card (with DxVA which also offloads a lot of the computing required from the CPU) and fully decoding with software on the CPU.

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There is such a beast but it'll cost you and I've no idea if it's ever been used in Australia.

Technotrend's Premium T (or the Hauppauge Nexus-T): see here. You'll probably have to contact Hauppauge in Germany and I think they're about 400 Euros (they were the last time I enquired about them). They were never officially released by Hauppauge.

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There is such a beast but it'll cost you and I've no idea if it's ever been used in Australia

The last time I inquired about them, they wouldn't support HDTV.

Same as the Nexus-S, which lost a lot of ground in sales with the advent of software based DVB-s cards.

Cheers

Renura

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  • 2 weeks later...

Hi,

I think having hardware decoder does have lots merits for external tuner cards. I'm sorry to say but I believe it is a bit presumptuous to assume that modern CPU are fast enough as this doesn't really apply to laptop users. My guess is most modern laptops can't run HDTV smoothly without some hardware assistance. That is unless you have the latest Intel Pentium 755 or AMD 64bit laptop or a destop replacement (ie heavy and poor battery life). The market share for machines of those caliber wouldn't be that big at the moment. FYI whilst quite a few users still requires portability (ie not 4kg+), long battery life, powerful CPU and GPU, laptops with all these attributes are rare at the moment (if at all). Believe me I've searched the globe for something like it.

I have the Nebula DigiTV USB hooked up to my Dell D800 1.6GHz Pentium M and it can't handle smooth HDTV playback. My laptop is only 1 year old, has 1Gb or RAM, 80Gb HDD(5400rpm), 128mb ATI Radeon 9600Pro (I am aware of the Catalyst driver issue). It was top specs a year ago and still handle most application pretty well but smooth HDTV playback on the Nebula still alludes it. There is definitely a market for an external DTV decoder with built in hardware decoding. I have been searching everywhere for exactly some thing like that and honestly wouldn't mind paying 400Euro for it. Hint, hint I would be a firm buyer.

Disregarding the HDTV aspect for a moment, the Nebula DigiTV USB is not really stable for laptop use (in my case anyway). FYI even when only displaying SD channels DigiTV would often crash whenever if I start calculations on a large spreadsheet (10mb+). You don't need to channel surf or run massive multimedia apps, Excel will crash DigiTV easily enough. I've given up running the DigiTV when I do any spreadsheet work, which is quite disappointing. FYI I have tried the server trick but the crashes still presist. Guess I will have to wait till dual core CPU laptops get released before I can do the simple task of working and watching the news at the same time.

I hope DTV product will evolve and properly address the needs of laptop users soon. Either that or I'll have to gamble that laptop will be powerful enough by the time I upgrade again next year....

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No the Nebula is USB 2.0 :blink:

However hardware decoding the stream and then trying to feed it though USB would probably cause it to choke...

BillC,

It just ain't going to happen. Although alternative USB 2.0 DVB-T tuner devices that will use software that utilise DirectShow decoders with DxVA will arrive soon. And at least offload some of that CPU load to the GPU.

Unreasonable expectations IMHO. But have you tried setting the process priority of DigiTV to "Above Normal" in the TaskManager before attempting the Excel calculations.

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