Hardware Deinterlacing

[minolta]

To pre or post deinterlace your truly-interlaced content? When using Divx, Xvid, or WME9 I've always chosen the latter to preserve the original; so I was happy when I found this on the microsoft site:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/directx9_c/directx/htm/settingdeinterlacepreferences.asp

Basicly, it says the video renderer can hardware deinterlace if VIDEOINFOHEADER2 specifies interlaced content. Both Divx and WME9 (sorry Xvid) correctly set the VIDEOINFOHEADER2 if "interlaced" is checkmarked in encoder.

So, I tested myself using some capped tv stuff and GraphEdit. The Divx clip plays weaved (as usual) even though VIDEOINFOHEADER2 tells renderer the clip is interlaced. The WME9 clip plays with weave or blend, depending upon its mood (honestly, it plays weaved first time through, but sometimes switches to blend later).

I think my older video card isn't so great (probably in software mode). Anyone with a newer ATI board willing to run a few tests? In future I'm hoping MPC will allow setting a preference (bob, blend, weave, hardware, etc).

Thanks,
Minolta

[avih]

eventhough dshow may support deinterlacing (hardware/software), i doubt it will outperform dscaler's deinterlacing. and u can use dscaler's code with ffdshow on arbitrary clips. cheap HW deinterlacers will never do as good as dscaler, and dscaler is relatively 'cheap' on cpu cycles with newer cpus.

so imho, it's better to stick to dscaler code because:
1. it performs better and it's more controlled.
2. your code will not depend on MS api, and therefore, will be easier to port to other platforms should this need arrise.