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[binary0110]

http://www.xboxdeveloper.net/index.php?mod...viewproj&id=245

I didn't realise that the Xbox could be used for PVR - does the Xbox have a video in? If it did then it could then PVR homebrew software could be the most useful feature of an Xbox (when coupled with a 120GB hdd  :lol: ) Considering that you can buy an Xbox for little more than 100 GB pounds, this is a lot more cost efficient.

Does anyone have any more info about Project Dreamix and whether the Xbox can take video in?

Binary0110

This post has been edited by binary0110: Jan 5 2003, 11:09 PM

[thedguy]

The Xbox gets Video and audio in thru a USB TV tuner/capture card.  Right now the group is trying to find a good USB adapter for cheap that (preferably) has linux drivers already.  right now the best done is around $200 usb adapter, and has bad reviews from most on vcdhelp.com  so it's not looking to good.

If ANYONE knows of any GOOD USB tv tuner/capture ( MUST have a TV tuner on it ) units that work on usb 1.0 please say so.  the cheaper in price the better.   From the way they are talking in their chan, they aren't gonna support multiple usb cards.   So i wouldn't jump the gun and go out and buy one right now until u know which card they are gonna support for sure.

[2000ache]

Time for the mod-guys out there (Xodus/Xecuter) to start building this thing

[merz]

that sound great!!!!!!!!!
             

[binary0110]

I know a little about video capture and I think the reason why USB TV tuners/capture cards get such bad reviews is because USB has a limited amount of bandwidth for video capture (compared with the PCI bus). However, I don't think USB tuners are all that bad and they would produce a perfectly good result given that the captured video would be viewed on a TV rather than a computer monitor (most TV card reviews consider playback only on a computer monitor which has a much higher resolution than a TV).

The Hauppauge WinTV USB (~50 GB pounds) captures at 320x240 (almost VCD resolution) and since the Xbox is also limited as a PVR device by its processor (for encoding the video), I think this would be fine as a USB TV tuner - assuming Project Dreamix goes live and it has linux drivers (I haven't checked).

Another option is WinTV Nova-T USB (~100 GB pounds) which captures digital terrestrial programs and streams the data (unchanged - MPEG2) to the computer. Presumably (of course assuming there are linux drivers) this would be a better solution because the quality is better and the Xbox isn't limited by its processor because it doesn't have to encode any of the captured video - it simply has to write it to hdd and play it back by decoding the MPEG2 stream.

The next step up is the PVR version of WinTV USB (~200 GB pounds) which captures analogue programs and encodes them to MPEG2 which is then transferred over USB to the computer. Effectively, the Xbox would receive the same kind of data as it would from the WinTV Nova-T, but I think it is less cost effective considering that you'd be able to receive more channels with WinTV Nova-T and it would be better quality.

For my 2p, I would urge Zpimpa to consider both the WinTV Nova-T USB and perhaps the analogue WinTV USB (because I'm not sure whether WinTV Nova-T USB works outside the UK). Working with Linux drivers may be a little tricky, though.

[2000ache]

I sure hope they pull this off. The box is getting better by the day

[Numpty]

I want to see how MS will go about implementing PVR..

[Zpimpa]

Xbox-scene and Members...

Thanks for the support so far, but the Dreamix team needs your help.  

Right now we are in need a coders to help speed up the software development process.  Also, those that are extremely knowledgable with both Xbox and PC hardware, we need your help as well.  Although we know video + TV capture can be done with the using Hauppauge's WinTV USB PVR device + USB Linux drivers (http://pvrusb.sf.net), we are looking for a more affordable alternative.  Remember, the alternate solution would have to include these three main features: TV tuner, USB Compatibable, capture cababilities and have USB Linux drivers (if not we can develop drivers but it will take time).  If a suitable USB device cannot be found, there is always the possibilty of modifying the Xbox in some way to put the card on-board.  However, this would most likely be too difficult for the average user.

Finally, if anyone is interested in looking into bringing USB2 to the Xbox, that would be of much help.   This would increase the capture rate which for WinTV PVR USB is currently (http://www.hauppauge.com/html/wintvpvrusb_datasheet.htm):
MPEG1 capture at 1150 Kbits/sec (Video CD data rate)
MPEG2 capture rates: 2MBit/sec, 4MBit/sec, 6Mbit/sec at full D1, plus S-VCD (standard play, long play, extra long play)

All help is welcome, but finding a better alternative to the WinTV PVR USB device right now is our main concern.  Email me or contact me on IRC with any questions or suggestions.  Website will be up soon.  Thanks

[binary0110]

Thanks for replying, Zpimpa.

I'm afraid I have absolutely no knowledge about software development so I can't really help you in that aspect. I am now beginning to see the problem regarding linux drivers. The only viable solution at the moment is the WinTV USB PVR but the cost is prohibitive.

Having just had a brief sweep around google, I can't find anyone who has currently got a project running to code linux drivers for the WinTV Nova-T USB because there is a lack of support from Hauppauge (I think they've concentrated on working on their PCI range of cards). There is a project underway for the analogue WinTV USB (http://linuxtv.org/) but I don't know how far that got and whether you were looking for a slightly better hardware solution than the analogue WinTV USB (as well as the fact that you would have to code a software MPEG encoder for the Xbox which will take a lot of time).

Of course, you've obviously researched this a lot more carefully than a brief sweep over google! If you want to save time, it looks like that the WinTV PVR USB is the best way to go, otherwise you'd have to attempt to code drivers for the other USB capture devices.

As for USB2, I'm not sure I'm convinced that it could ever be brought to the Xbox considering that to install it, it would require vast amounts of hardware modification which even the most competent modder wouldn't find easy. In addition, you'd have to code the software to run the bus which I'm guessing would be a lot more complicated than coding the drivers for the other WinTV cards.

Anyway, let us know how you get on.

[switzch]

I really dont see how this would work.

TV is captured at 3.6mb /sec for DV video, thats with fairly good compression.  Even at a lower resolution, it wouldnt be less than 2mb/sec.  

USB cannot capture at that data rate.  So if the PVR feature were ever implemented it would have to either compress the data at the streaming rate of the tv show (which i doubt that the xbox could handle), or it would just look like shit.

If someone could develop a video input into the LAN card, that would be fast enough, and would be much much better.  But good luck finding or making that.

sorry for the pesimistic view.

[rjm2k]

QUOTE (switzch @ Jan 6 2003, 03:28 PM)

I really dont see how this would work. TV is captured at 3.6mb /sec for DV video, thats with fairly good compression.  Even at a lower resolution, it wouldnt be less than 2mb/sec.   USB cannot capture at that data rate.  So if the PVR feature were ever implemented it would have to either compress the data at the streaming rate of the tv show (which i doubt that the xbox could handle), or it would just look like shit. If someone could develop a video input into the LAN card, that would be fast enough, and would be much much better.  But good luck finding or making that. sorry for the pesimistic view.

This is why I think the only real option is something like the WinTV PVR USB, which afaik sends an MPEG stream over the usb after doing all the hard work.  I guess it would be possible to have a device which uses ethernet to connect instead of USB, but afaik there isnt such a device at the moment (apart from a PC with a capture card of course).   Perhaps a hybrid approach is possible (though not cheap) - allowing a remote pc to encode and then transfer to the pc over ethernet.

As for adding usb 2 to the xbox, i doubt that would happen, I'm not sure how the usb support is implemented, but I'd expect such an upgrade to require quite a lot of soldering, and the unlikely possibility of finding usb2 chips which are pin compatible with whatever the xbox uses.

[BenJeremy]

QUOTE (switzch @ Jan 6 2003, 11:28 AM)

I really dont see how this would work. TV is captured at 3.6mb /sec for DV video, thats with fairly good compression.  Even at a lower resolution, it wouldnt be less than 2mb/sec.   USB cannot capture at that data rate.  So if the PVR feature were ever implemented it would have to either compress the data at the streaming rate of the tv show (which i doubt that the xbox could handle), or it would just look like shit. If someone could develop a video input into the LAN card, that would be fast enough, and would be much much better.  But good luck finding or making that. sorry for the pesimistic view.

DV is 720x480@30fps.

NTSC is 320x240@30fps.

DV is not MPEG, it's barely compressed.

NTSC, via a USB adapter, is sent as MPEG1 streams.

Should work fine at VCD quality, which, BTW, is marginally better than VHS tape. Depending on the quality of the MPEG encoding, it may even do a decent job removing the compression artifacts.

[binary0110]

QUOTE (rjm2k @ Jan 6 2003, 04:55 PM)

Perhaps a hybrid approach is possible (though not cheap) - allowing a remote pc to encode and then transfer to the pc over ethernet.

http://www.snapstream.com/

AFAIK, it is now possible to stream TV onto a Windows CE handheld device over a wireless network. It wouldn't be difficult to do the same with the Xbox over ethernet, but it requires the use of a video server (just like a "relax" server). The beauty of using a USB TV tuner with the Xbox is that it is a self sufficient, standalone system

As for the hardware options, if we were to use the 50 pound WinTV USB which has a limited resolution, I'm still confident the quality would be adequate given that it will be played back on a TV rather than a computer monitor....however, I'm not sure whether the Xbox processor could cope with the MPEG 1 encoding demands (I'm pretty sure a hardware MPEG1 encoder isn't part of the WinTV USB's specs.) and it doesn't (yet) have linux drivers. On the other hand, the WinTV PVR costs a lot of money (almost twice as much as buying an Xbox in the first place). However, I'm sure that team Dreamix will look at all possibilities and I wish them the best of luck as they take on this difficult project.

[BenJeremy]

QUOTE (binary0110 @ Jan 6 2003, 02:26 PM)

QUOTE (rjm2k @ Jan 6 2003, 04:55 PM) Perhaps a hybrid approach is possible (though not cheap) - allowing a remote pc to encode and then transfer to the pc over ethernet. http://www.snapstream.com/ AFAIK, it is now possible to stream TV onto a Windows CE handheld device over a wireless network. It wouldn't be difficult to do the same with the Xbox over ethernet, but it requires the use of a video server (just like a "relax" server). The beauty of using a USB TV tuner with the Xbox is that it is a self sufficient, standalone system As for the hardware options, if we were to use the 50 pound WinTV USB which has a limited resolution, I'm still confident the quality would be adequate given that it will be played back on a TV rather than a computer monitor....however, I'm not sure whether the Xbox processor could cope with the MPEG 1 encoding demands (I'm pretty sure a hardware MPEG1 encoder isn't part of the WinTV USB's specs.) and it doesn't (yet) have linux drivers. On the other hand, the WinTV PVR costs a lot of money (almost twice as much as buying an Xbox in the first place). However, I'm sure that team Dreamix will look at all possibilities and I wish them the best of luck as they take on this difficult project.

Well, heh heh, it might be twice the price of an Xbox in the UK or Oz land, but here in the US, those devices are usually pretty reasonable.

[konfoo]

You don't need snapstream to stream over a network to a CE device. Just download windows media server and encoder from M$'s site.

As for the digital TV - forget it. DTV comes in at 4-19Mbits on average. Terrestrial DTV tuner boards receive broadcasts from broadcasters that send a small amount of SD material but will all eventually switch over to HD bandwidth in the long term (2-3 years). So the development effort on this type of PVR isnt even worth it because even though the DTV USB boxes can support DTV, they can only support a DTV program stream <6Mbits. Anything more cannot be passed through the USB1 bus.

The only PVR you will be able to use on the Xbox over USB1 is one that can handle <6Mbit. Of the boxes out there (like the hauppage, which sucks BTW - total hack job), these that fit the bill are in the MPEG1 320x240 range. I doubt the xbox hardware can cope with encoding D1 in realtime with audio via USB1 feed into MPEG2 or MPEG4 (a 700mhz P3 barely can do live MP4 encoding @ 320x240). This kind of quality is acceptable for watching on a TV but if I were working on a PVR for a PC (which I am), I wouldn't even waste effort coding something to create VCD quality material.

Just my 2c.

This post has been edited by konfoo: Jan 6 2003, 10:23 PM