An engine of the digital signal type

[IIfx]

A photo-engine to be exact. I at last got my hands on a Radius Photoengine DSP card on ebay for the sum of 41 dollars. I don't care if it cost a little more than I wanted, I have wanted one for about 2 years.

All I need now is a good video card to go with it in my Quadra 800. Currently I have a VideoVision Studio in it, but that does not output the resolutions I want. (Although I am using a 640x480 apple monitor, so I don't think it matters until I get a flat panel LCD.)

 

[Unknown_K]

The built in Q800 video isn't that bad, max res is 1152x870 4bit or 8bit depending on stock 512K VRAM or 1MB VRAM(upgraded).

 

[IIfx]

Unknown_K, you have reminded me that the built in video is actually decent. (I have not used it for a long time, and I remember color options topping out at thousands, but it was fast)

 

[Unknown_K]

Built in video is faster then anything that has to go over the Nubus bus (on Quadras anyway). The problem is people want more color depth and/or higher resolution and better quickdraw acceleration so they get a fancy Nubus card.

I have a bunch of Supermac Thunder/24's some with Gworld RAM and some with the DSP add-on for doing 1024x768@24bit. Those cards are a decent compromise for speed, resolution, DSP, and color depth. There are newer and faster cards out there, but you will pay a decent amount for them.

 

[IIfx]

I do tend to forget that nubus is about as constrained in data speed as ISA. Nubus90 is better sure, but still is inferior to PDS.

(Going by memory, I think most macs have built in video hooked into the system on PDS)

Why weren't there PDS video cards for the Quadra 800? It looks like the PDS slot is lined up with the 3rd slot perfectly.

 

[CelGen]

I sourced my second PhotoEngine about two weeks ago. Fun.

It seems to be happy in Photoshop 3 but not so much in anything newer.

 

[IIfx]

Its a shame support is limited for it, but its a cool historical relic.

If only the DSPs could be used for more than that. 4x66mhz DSP in any 68k is a great boost.

 

[trag]

Why weren't there PDS video cards for the Quadra 800? It looks like the PDS slot is lined up with the 3rd slot perfectly.

NuBus was already a fairly small market. If you then limit your market to just one specific Mac model, your NRE costs per unit go out the window.

Of course, a PDS video card for the Q800 would have worked in the Q650 and C650 as well and perhaps in the C/Q610, but that's still a pretty small market compared to all NuBus Macs.

 

[IIfx]

The PDS of the 800 was common to a lot of 040 macs. I know the 950 also uses the same PDS. Actually all 040s may share the same PDS bus, as the PPC Upgrade card worked in all of them. (Excluding LC based 040s)

 

[Unknown_K]

The only things sold for the 040 PDS slot were CPU/Cache upgrades and some very rare SCSI cards, none of which were cheap.

 

[IIfx]

Ok! I got it in the mail, and I am actually a bit disappointed in it. Sure its cool, but once you see the operational flaws with it, it becomes an expensive toy.

For one thing, it only accelerates some of Photoshop 3's filters and functions. A lot of stuff is still done on the CPU only.

I am confident that if someone wrote plugins, you could use the DSP for more than just some Photoshop functions. Perhaps to decode an MP3, or encode video taken with a capture card. The possibilities are limitless until you realize that information to accomplish this is long gone.

Coolness factor is a 5/5. 4 60mhz DSPs? That just sounds and looks cool. It has blinkenlights.

Actual review score is a 2/5. Without extra plugins that work with it, and the limit to only accelerating Photoshop when it could in theory do so much more, it gets a C. But, it is a good slot filler to put in those extra nubus slots. If all photoshop render actions were offloaded to the DSP it would get a 4/5. Sadly not.

The box is propaganda.

 

[trag]

I am confident that if someone wrote plugins, you could use the DSP for more than just some Photoshop functions. Perhaps to decode an MP3, or encode video taken with a capture card. The possibilities are limitless until you realize that information to accomplish this is long gone.

Welllll....

The datasheet for the AT&T DSPs can probably still be obtained. So writing code for them can be done. The tricky part would be figuring out how the Mac transfers data to the card and receives the results. However, disassembly of the existing plug-ins might shed light on that subject. You know pretty specifically what the card does. It shouldn't be too horribly difficult to reverse engineer at least some of how the card gets data off of the NuBus.

 

[Unknown_K]

If you look at the Audiomedia I and II Nubus sound cards you will find it does have an onboard DSP to do sound encoding, and all of the Nubus era Video editing systems also had DSPs. The problem you run into is stand alone cards are too slow for some functions because you are dumping the data back and forth over the Nubus BUS. The best DSP card for photoshop were the last Radius cards with the DSP on the card itself. The last AVID Nubus editing systems had a data cable tied directly from the capture card to the DSP card so they didn't have to use the Nubus BUS.

The very first Quickdraw accelerators were nothing more then a couple DSP's on a Nubus card with some RAM, and those died out quick because they were too slow (I have a couple Rasterops cards in use and they do speed things up, but also bog down the Nubus BUS).

Another early use for DSPs were JPEG compression and decompression cards, I think Picturepress was one of the apps that used them. Early 68K processors were not optimized for that kind of work. They also did a specialized DSP chip/card for HD data compression.

All in all they are fun cards to mess with on Nubus Macs, I have quite a few, but I would not spend too much money on them since they are very specialized.

 

[CelGen]

I believe the photoshop plugin that came with Avid Videoshop 3 allowed for coupled filter acceleration so long as what you were doing in Videoshop was something that the Photoengine accelerated in Photoshop.