ATI AVIVO desirable? or not?

[three_jeeps]

Hi:
I am looking to get an ATI AIW card as part of creating a video capture setup primarly to convert VHS tapes to DVDs. In looking at the ATI AIW history in Wikipedia, a small set of AIWs (x1900, x1800XL, AIW2006) have AVIVO capabilities. AVIVO is a capability designed to offload video decoding, encoding, and post-processing from a computer's CPU to a compatible GPU on the AIW card. On the surface, this sounds like a good thing - essentially signal processing done by a specially designed chip to alleviate using functionally equivalent software algorithms being run on the CPU.

So my question is, in reality, is it desirable to have a capture card with this functionality? What are the pros and cons of having a card with VIVO if my intention is to use it in a system that has a 2.8GHz single core, hyperthreaded CPU, 4GB of memory, running windows XP and the card sitting on the PCIe bus? I plan on experimenting captures with lossless and lossy algorithms, using VirtualDub.
Thank you for your input.

-John

[msgohan]

This functionality will never be used if you capture using VirtualDub.

[three_jeeps]

Quote:

Originally Posted by msgohan

This functionality will never be used if you capture using VirtualDub.

OK, ty.
If I don't use virtualdub, is there a capture scenario that would make use of the capability and if so, is it advantageous vs virtualdub?

Thanks
J

[sanlyn]

Quote:

Originally Posted by three_jeeps

I plan on experimenting captures with lossless and lossy algorithms, using VirtualDub.

Why use VirtualDub to record VHS to lossy codecs? If your priority is the best quality capture for further work, archiving, and unlimited choices for final encoding, go with VirtualDub and lossless. If your priority is quick lossy encodes and you're willing to live with lower quality and lossy final delivery formats not designed for further work or editing, you're wasting time and money with AIW and VirtualDub. Why not get a DVD recorder or PVR?

[three_jeeps]

Quote:

Originally Posted by sanlyn

Why use VirtualDub to record VHS to lossy codecs? If your priority is the best quality capture for further work, archiving, and unlimited choices for final encoding, go with VirtualDub and lossless. If your priority is quick lossy encodes and you're willing to live with lower quality and lossy final delivery formats not designed for further work or editing, you're wasting time and money with AIW and VirtualDub. Why not get a DVD recorder or PVR?

Thank you. As my post indicated, I would be doing some experimentation and was wondering about alternative approaches. Yes, my ultimate goal is getting the best quality capture for down stream processing. I do know a bit about signal processing (from the mathematical perspective) what I don't know is what functionality is present in what hardware. I do understand about various signal processing approaches and how that functionality is implemented in both HW and SW. I don't know specifically about the video processor on the ATI card and equally important, if VirtualDub configures the ATI card to bypass the special video chip (from your comment, it apparently does). I thought that perhaps the video processor chip would perform such functions as: h and v sync shaping, jitter adjustment, hf filtering to reduce noise, any attempt at luminance & chrominance equalization/auto correction, etc.
Yes, I could try to find the data sheets for the video chips, a block diagram of the signal flow on the board, etc. but my guess is most of the stuff is proprietary. Textual descriptions might help, if detailed enough. So instead of going down that road initially, I thought I'd ask about experiences and insight from ppl that have done this sort of thing before. I appreciate you comments.
J

[sanlyn]

It's been a while since I used ATI's AVIVO, but it does work some automated image enhancement, auto gain, primitive blurry noise reduction, and a great many of the things that no one would ever recommend for VHS capture, much less for most other video processing -- unless you want to get involved in a genuine professional shop product that requires training plus additional support hardware, software, money, and carefully calibrated setup. GPU encoding is not that great, so there's no advantage to that. In the past there are complaints about advertised features with only spotty driver support, deinterlacing that makes garbage out of once decent video, poor color processing, and a host of nasties that no one ever expected, usually because you pretty much have to get into headachy detail about setup, settings, and operation. Many people mistakenly think that VHS sources are good candidates for HD ; some are happy with AVIVO doing that, some just uninstall AVIVO and use better methods, many forget about making low resolution look like high resolution. Other users write praise as if AVIVO led them through out of body experiences into video nirvana, others just say it works "great" and that they enjoy the results, others just say it's OK.

What's stopping you? Have you consulted an AVIVO manual? There must be a ton of internet posts concerning AVIVO, things that work and don't work, and user experiences. Years ago when I used it, in the Pleistocene Era of Standard Def and CRTs with more accurate imaging than LCDs, I was completely underwhelmed. Your mileage might differ.

Must be someone around here who uses AVIVO currently.

[msgohan]

^ I pretty much agree with sanlyn's entire post.