720p vs 1080i with Hauppauge HD PVR

[mces97]

I just received this today and I have to say, when watching tv when the tuner is set to output 720p video the picture looks amazing. I am disappointed however on how 1080i looks. It looks like frames blend together and are not as crisp. I know progressive is better however when I watch 1080i on the tv directly from my cable box it does look better than 720p. Does anyone have any suggestions how to get the quality of 1080i videos more up to par. Thanks

[autoboy]

what resolution is your TV?

[mces97]

my tv is 720p. I am not sure why that would make the video look the way it does. I have played 1080i video before and it looks good. 720p from the hd pvr looks as smooth as it did on my tv before, but like I said 1080i looks much worse on the hauppauge then when I viewed it straight from the tv. You have not noticed 720p videos running better. Maybe it is my setup. I wonder if I got a gpu that was hardware accelerated if that might make it perform better.

[Fuzzy]

It sounds like the videos are not being deinterlaced properly in your decoder. If you don't have hardware accelleration, then I'm pretty certain you don't have the CPU to do the actual deinterlacing of the already hard to decompress H.264 files that the HD-PVR creates. Either way, the non-deinterlaced images are keeping their interlaced image, which is then getting scaled to 1280x720, which is how the two fields are being blended together (poorly).

If you don't want to get a new vid card, you should be able to lock your STB to 720p, and the deinterlacing will be done there. If you can't view the vids at 1920x1080 anyways (as your tv is only 720p), you might as well keep it lower.

[autoboy]

If your TV is 720p then you should probably set your STB to output 720p or you end up double scaling a lot of content. If you get better results with 720p then all the more reason to use 720p. Also, make sure your computer or hd extender is set to 720p as well.

IMO, only people who have 1080p TVs should set the output of their STB to 1080i and even then most of your content will then be double scaled and double deinterlaced. Contrary to popular belief, upscaling / deinterlacing reduces the quality of the original content rather than improving it. You are better off with less scaling steps than more.

[mces97]

Well eventually I plan on getting a 1080p tv, so I wanted to archive movies in 1080i. How many of you think a new videocard would with hardware acceleration would be able to properly deinterlace 1080i video? I would definitely look into that.
Thanks

[autoboy]

what are your system specs?

[mces97]

Windows xp sp2, core 2 duo 6420 running at 2.6ghz, ati x1650xt. 2gb gskill ddr 800. I have no problem playing 1080p h264 videos, so I know the system is capable of handling the videos produced by the hd pvr. I might try next getting a gpu that does hardware acceleration. Maybe arcsoft with get a better encoder to deinterlace the 1080i streams, or maybe eventually they will support 1080p even.