@jahc

It's not just a matter of wanting to do this or that, it's also a matter of how much work it is, whether there is any info available on it, and for most devs in the Amiga world, it's a matter of priorities, e.g. what efforts are worth spending more time with. There is far more to do than developers available, but if people keep complaining and putting pressure on the already overloaded devs they will just chase them away...

@COBRA

Okay, sorry.

@jahc

Quote:

Can the Radeon be used to make DVD playback smooth on Sam?

Basically it's a question of putting the right code in the right place.

From what I understand the process of decoding mpeg2 consists of:
Variable length bitstream decoding (huffman decompressor or something?)
Inverse quantization (variable bit lengths used depending on importance of information)
Inverse Discrete Cosine Transform (this is where most CPU time is normally used)
Motion Compensation
Final image reconstruction
Color space conversion (YUV to RGB)

I hope the CSC is already done inside the graphics card, using an YUV overlay buffer.
If not, pixel shaders can be used to do this.
But if the pixel shaders could be used to do the motion compensation and final reconstruction, then there are some really good possibilities.
If the pixel shaders can be used to do IDCT as well, then we're talking a 50% reduction in CPU use here
GPUs are REALLY good at matrix transformations, so the IQ stage is a very good candidate...

Problem is, you can't pass data twice over the PCI bus, so you can't use the GPU to do IQ followed by IDCT in the CPU.

But I would pay real money to see the pixel shaders put to some use here. If someone buys the flex board and puts a Radeon HD2400 card in there, it really would be nice to use that processing power to offload the CPU.

This was rather informative, actually:
http://www.graphicshardware.org/previous/www_2006/presentations/han-VideoDecodingOnGPU-gh06.pdf

There is a lot of information out there, but unfortunately there are a few very generic patents...

Another interesting article, mentioning the 2D capabilities of the pixel shaders in the M9:
http://ati.amd.com/developer/shaderx/shaderx_imageprocessing.pdf

_________________
This weeks pet peeve:
Using "voltage" instead of "potential", which leads to inventing new words like "amperage" instead of "current" (I, measured in A) or possible "charge" (amperehours, Ah or Coulomb, C). Sometimes I don't even know what people mean.

@olegil

Of course YUV overlay has been used for a while now. The huffman and dequantization part is very fast, even an old 68k could more than handle that part without issues. The IDCT and motion compensation/reconstruction part is the most CPU-hungry.

@COBRA

Yeah, figures. But I honestly do suspect that feeding the pixel shaders the output of the IDCT and the macroblocks and let the GPU do the rest is possible.

And a PCI Radeon x1550 or HD2400 could even do IDCT. The trick is of course piping the output of one block directly into the next block without needed to go in to PCI

_________________
This weeks pet peeve:
Using "voltage" instead of "potential", which leads to inventing new words like "amperage" instead of "current" (I, measured in A) or possible "charge" (amperehours, Ah or Coulomb, C). Sometimes I don't even know what people mean.

@COBRA

Let me thank all you developers for all your hard work so far.I'm sure it is done as much for the love of the Amiga platform as any other reason.

Still, I think we should be honest in recognizing whether the weakness of a function is hardware or software related.Only then can we decide how best to correct,accept, or work around those weaknesses.
An OS can be almost as complex as a person;some people are successful at many things ,yet still have tasks they find difficult.We still value those people.We still value the Amiga.

In response to customer suggestions, we have now added an option to configure this product with hard disk pre-installed with OS 4.1:

http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=869#configure

Hard disk will be fully prepped/formatted and OS 4.1 installed. Customers will also receive OS 4.1 CD and license code.

Here is a picture of the new 600Mhz boards:
http://amigakit.leamancomputing.com/catalog/images/sam440-600mhz.jpg

Last edited by amigakit on 07-Mar-2009 at 05:19 PM.

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@anyone

Has anyone heard of why the SAM power connector is in vertical position on some SAM boards and in horisontal position on some other.


AND it seems that the Lattice expansion connector is back!
At least on the 600Mhz board.

Last edited by KimmoK on 07-Mar-2009 at 07:19 PM.

_________________
- KimmoK
// For freedom, for honor, for AMIGA
//
// Thing that I should find more time for: CC64 - 64bit Community Computer?