Second Gen Cell info

[PC-Engine]

BTW wouldn't it be pretty funny if the actual realtime cutscenes looked better than that pic? Of course only PS3 would be able to accomplish that since CELL can stream MPEG2 clips very well.

Eh? Since when do "realtime cutscenes" require MPEG2 decoding?

That was sarcasm...

 

[Blazkowicz]

LOL.. Cell in TVs make sense now, it's made to accomplish what we can see in Back to the Future II (and some guy seriously proposed it )

 

[Tacitblue]

The crazy flipside of that would be hypothetically that in a replay mode while a lot of non gameplay geometry usage like calling your next play they can render in non realtime extra effects using multipass textures and geometry, encode to an mpeg file and replay it as an embedded video overlay in a stadium scoreboard for instance giving more detail than they might have otherwise.....unless i'm totally thinking in a circle here.......could that be done? Lil renderman minifarm module using temporarily unused SPU's.

 

[Blazkowicz]

Thanks one, quite impressive, so each of the 6 SPE's handled 8 streams. I'd assume this is a tech demonstration not only for Cell's power in general but specifically in the HDTV market which Sony and Toshiba have in mind. Instead of flicking through channels why not display a dozen or so at once and select the one you like.......who needs tv guide.

this was already done.
I played a bit with satellite TV (not mine, it's too expensive, I rather have bandwith). There was a "meta-channel" with 25 or so thumbnails. select one with the up/down/right/left on your remote control and you get the sound from that channel (may be enough if it's music), press OK and you switch to that channel.

 

[PC-Engine]

You would need 48 tv tuners though, unless you have a really fast channel scanning tuner.

 

[Tacitblue]

Was meta channel done on the fly in the box, or was it a seperate channel stream with embedded controls to recognize the different thumbnails? I'm still in the dark ages here, cable is all i can get on my side of the building, sats aren't in my view of the sky. Shame.

 

[Blazkowicz]

of course, it is sent by the TV provider (your second solution)
limited DVD-like interaction allows it.

The other way of doing this sounds like rendering Toy Story in real time to watch it or compiling your whole OS and apps before installing them (just kiidding on this once )

 

[PC-Engine]

Was meta channel done on the fly in the box, or was it a seperate channel stream with embedded controls to recognize the different thumbnails? I'm still in the dark ages here, cable is all i can get on my side of the building, sats aren't in my view of the sky. Shame.

They were MPEG2 files loaded from a HDD. They were not over the air broadcasts.

 

[one]

So a modern 3.4 ghz machine could probably decode at least 12 SD MPEG2 streams simultaneously.

More streams, more memory bandwidth... I don't think it can scale linearly on an ordinary PC setup.

 

[Blazkowicz]

Was meta channel done on the fly in the box, or was it a seperate channel stream with embedded controls to recognize the different thumbnails? I'm still in the dark ages here, cable is all i can get on my side of the building, sats aren't in my view of the sky. Shame.

They were MPEG2 files loaded from a HDD. They were not over the air broadcasts.

is there some confusion?
Yes, the cell demo was done from HDD; what I'm talking about is what we've had for years on sat TV, this is broadcasted over the air (and space).

 

[PC-Engine]

Was meta channel done on the fly in the box, or was it a seperate channel stream with embedded controls to recognize the different thumbnails? I'm still in the dark ages here, cable is all i can get on my side of the building, sats aren't in my view of the sky. Shame.

They were MPEG2 files loaded from a HDD. They were not over the air broadcasts.

is there some confusion?
Yes, the cell demo was done from HDD; what I'm talking about is what we've had for years on sat TV, this is broadcasted over the air (and space).

Yeah I thought he was talking about the demo.

The crazy flipside of that would be hypothetically that in a replay mode while a lot of non gameplay geometry usage like calling your next play they can render in non realtime extra effects using multipass textures and geometry, encode to an mpeg file and replay it as an embedded video overlay in a stadium scoreboard for instance giving more detail than they might have otherwise.....unless i'm totally thinking in a circle here.......could that be done? Lil renderman minifarm module using temporarily unused SPU's.

This has already been done way back during the Playstation days. Anyway with regards to muliple channel thumbnails, with a really fast channel scanning tuner inside the box you could probably get low framerate thumbnails going with frame skipping.

 

[Blazkowicz]

So a modern 3.4 ghz machine could probably decode at least 12 SD MPEG2 streams simultaneously.

More streams, more memory bandwidth... I don't think it can scale linearly on an ordinary PC setup.

If the streams where interleaved so the read was fully sequential and not random access (I guess this was the case), I think a cheap RAID 0 array can cope up, perhaps even a single disk. /edit : was thinking of the 48 streams demo, and only about HDD I/O not RAM.
6.4GB/s on current PC is still quite good? you can decode one stream with old old PC with 500MB/s (66mhz fsb/sdram)

 

[one]

Was meta channel done on the fly in the box, or was it a seperate channel stream with embedded controls to recognize the different thumbnails? I'm still in the dark ages here, cable is all i can get on my side of the building, sats aren't in my view of the sky. Shame.

They were MPEG2 files loaded from a HDD. They were not over the air broadcasts.

is there some confusion?
Yes, the cell demo was done from HDD; what I'm talking about is what we've had for years on sat TV, this is broadcasted over the air (and space).

??? According to you

select one with the up/down/right/left on your remote control and you get the sound from that channel

only 1 sound channel is processed in realtime in Metachannel. Where's similarity?

 

[PC-Engine]

So a modern 3.4 ghz machine could probably decode at least 12 SD MPEG2 streams simultaneously.

More streams, more memory bandwidth... I don't think it can scale linearly on an ordinary PC setup.

If the streams where interleaved so the read was fully sequential and not random access (I guess this was the case), I think a cheap RAID 0 array can cope up, perhaps even a single disk. /edit : was thinking of the 48 streams demo, and only about HDD I/O not RAM.
6.4GB/s on current PC is still quite good? you can decode one stream with old old PC with 500MB/s (66mhz fsb/sdram)

Yeah if someone can do some simple math with estimated bitrates for these streams, I don't think any modern PC with dual channel DDR would have any problems at all. At 640x480 you can probably get away with 1Mbps bitrate for each stream which in turn is only a measely 48Mbps or 6MB/s bandwidth. Even if you increased the bitrate to DVD quality levels at say 8Mbps (1MB/s) for each stream, it still would be only 48MB/s well within the PC's bandwidth limits.

 

[Blazkowicz]

??? According to you

This is self-evident. I first saw that 6 yearish ago, I don't think there are 25 tuners and MPEG2 decoders in the small black box, plus some thing to composite all the images.

select one with the up/down/right/left on your remote control and you get the sound from that channel

only 1 sound channel is processed in realtime in Metachannel. Where's similarity?

The similarity is you still see 25 (it was maybe 20, or 30, whatever) moving images at 25fps (no 30fps NTSC junk ), and I was replying about Tacitblue's idea, which is good but has been implented more simply. could you hear anything if you heard all that crap at the same time? It's already painful when Marty junior watches six channels at the same time in 2015

if anything the Cell demo proves that the tv provider could do their fancy thing with just one Cell, and that yes, Cell will be great for video and graphics workstations.
Now we still have to see how it can be used for gaming

 

[one]

How about the overhead in thread context switches on Pentium4? Hyperthreading limits the effective size of a cache, hence less mem bandwidth...

 

[seismologist]

you nedd 48 tunner to lock every frequence of every channel

or one Cell...

 

[PC-Engine]

you nedd 48 tunner to lock every frequence of every channel

or one Cell...

Huh? Cell doesn't have a receiver/tuner...

 

[Blazkowicz]

you nedd 48 tunner to lock every frequence of every channel

or one Cell...

Huh? Cell doesn't have a receiver/tuner...

but it's a BroadBande Engine

 

[PC-Engine]

but it's a BroadBande Engine

Oh yeah that's right.