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Hi Andreas
maybe you should just hang in there until Q1 2009 when, hopefully, Cyberlink will announce the ATI patch, and with luck that will have more functionality than the current CUDA patch.
I think the fact of the matter is that it's still early days for gpu encoding, even though the technology has existed for a while.
It's interesting to consider an AVCHD camcorder. The onboard image processor has to encode the video to AVCHD "on the fly" - and clearly there isn't the room or power available for it to use a Q6600 or even a QX9770. Besides which, neither of those processors would manage to do the encoding quickly enough anyway.
So, using a dedicated hardware encoder, the camcorder can do the task using much less power and with a far simpler and smaller processor. I suspect there is a certain amount of parallel processing used, though the manufacturers never seem to release much in the way of technical details.
When you compare the performance of the current generation of AVCHD camcorders with the previous ones, it's also clear that important developments and advances in image processing technology are being made - and still need to be made. That will hopefully reduce motion artefacts, for example.
Returning to encoding on a pc, when you consider the potential speed gains, there just has to be an increasing head of steam pressing for development, and the first software to feature proper implementation of GPU encoding will have a huge advantage over all the others. The encouraging thing is that thus far, Cyberlink seem to be ahead of the mainstream pack.
I think many people don't appreciate the scale of the speed gains possible. Whilst you might reduce your encoding time by a factor of maybe two or even three by opting for a very expensive top of the line cpu, the potential is for a tenfold or more speed gain simply by using a mid range gpu.
It's entirely possible that some owners of Extreme Edition processors will be mightily peeved if a "lesser" pc equipped with a relatively low-priced video card can encode video at many times the speed of their own system.
I'm all about "bang for your buck" myself, so I'm as anxious as you to see what Cyberlink can do with ATI AVT support, and hope that AMD work with them to bring it about.
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It's frustrating, isn't it!
The CUDA patch has been available for some time now. There must be PD7 users with suitable NVIDIA graphics cards in their pc's, but nobody seems interested in running some simple tests to properly evaluate the effect of CUDA support. I've only read the vaguest references to CUDA usage, generally in the form of complaints that it didn't seem to do much.
I would perform tests myself - but don't have a suitable video card. Since I anticipate upgrading my pc in the near future, I'm very interested in the benefits of CUDA or AVT support.
Certainly from the publicity material that Cyberlink have put out, CUDA should speed up video encoding, and by several times the speed at which even the fastest cpu can do it. It's not clear to me if that speed increase will only be gained when encoding to h.264, or if it will occur when, say, transcoding to mpeg2.
AVT support seems to have even more promise. AMD demonstrated a pc encoding four HD video streams to h.264 in real time. Compare that with a top of the range Intel Quad taking ten hours for a single stream, and you can see the potential benefit.
A glimpse of the performance benefit of CUDA is demonstrated by the otherwise poorly featured "Badaboom" program.
I believe the ATI 4800 series video cards, having many more stream processors than even the latest NVIDIA ones, have greater potential as parallel processors used to offload video encoding from the cpu.
If AVT support is or can be properly implemented, it should change everything. Instead of paying top dollar for the fastest cpu, the optimum system for video editing might comprise a lower-end cpu paired with a mid-range to upper mid-range video card.
There's also the possible additional benefit of having multiple video cards.
The kind of parallel processing that GPU's can perform is well suited to video encoding, which is a relatively simple process readily divided up into smaller "chunks", so you would expect video encoding to be just about the first pc task taken on by video cards.
If it turns out that the benefit is limited to h.264 encoding only, the principal benefit may be to HDV users, if they wish to target their projects to AVCHD. It should also show a benefit to AVCHD users, however, if they are making much use of video filters, transitions, and so on, and anything else that would prevent SVRT from functioning. Of course in that case, however, you need to have a video editing program that actually can edit AVCHD satisfactorily in the first place, and I think we're some way off that at the moment. 
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On December 11th, AMD have promised to release their own GPU-accelerated H.264 transcoder. Compared with the CUDA "Bababoom" program, AMD claim it will be significantly faster - perhaps reflecting the increased number of stream processors in ATI video cards such as the 4800 series.
Check out this Anandtech article:
http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3457&p=3
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Hi Andreas,
for all our sakes, I hope it's not true!
I have some encouraging news, however.
After bandying emails with Cyberlink support, I finally bullied the following response from them:
"Thank you for contacting CyberLink Technical Support.
We understand your concern related with PowerDirector software.
We can very well understand your concern and the implication of this situation as a user and apologize for any inconvenience faced by you.
In regards to your concern, we would like to inform you that PowerDirector 7 will supports ATI AVT on 2009 Q1. We will keep to cowork with ATI. And we also want to inform you that we need ATI to share this technology to us for integration."
That will be very good news indeed, and if the improvement in transcoding speed bears a meaningful relationship to the number of available stream processors in a graphics card, the ATI series should be a VERY good card to have!
Interesting also that the imlication seems that AMD are dragging their feet on this one.
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Although it's a totally different product, there might be some relevance in the test results of various NVIDIA video cards with "Badaboom", a CUDA enabled program. You can see some figures in this article, which I believe may have been mentioned by a previous poster.
http://www.anandtech.com/video/showdoc.aspx?i=3374
Now whilst it would be impossible to make any direct comparisons, it could be that similar ratios of performance gain from different cards might apply to PD7. That might suggest the 8800GT as a reasonable candidate, at around $140, or the 9800GTX at around $180. If CUDA works in PD7, it would mean you could use a lesser cpu. If you're wanting quad core anyway, that might logically be a Q6600, giving a good balance of non CUDA performance and cost.
Of course if the promised ATI hardware acceleration works with the HD4800 series, it makes a Phenom cpu with a 4800 series video card look like a nice machine to me, since the Phenoms can be had at pretty competitive prices and AMD motherboards also tend to cost less than Intel ones.
I've emailed CyberLink to see if there is any info on GPU encoding with the HD4800 series. As I see it, that feature could easily be a deal maker for an increasing number of people struggling to edit AVCHD.
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So now the patch has been released - do any users have any practical experience of using it?
I'd be very interested to see the speed gains with a range of different cpu/gpu combinations. After all, not everyone can hope to have a top-end GPU, and maybe there will prove to be an optimum combination of a moderately fast cpu paired with a mid to high-end gpu.
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