Downsampling grain?

[CJS234]

Ok by downsampling I mean that since my TV is only 1366 x 768 (yet can still take 1080i), the PS3 does this downsampling to make the 1080p picture fit into the 1366 x 768 limitations and thus makes the grain more visible. Thats what I think. There are rumors (hope its true) that Sony is going to fix the downsampling problem for 1080i tv's on a future PS3 update along with adding 1080p upscaling for regular dvd's. Keep your fingers crossed

Thanks for all your help again,
CJS234

[Deciazulado]

As I said a couple of posts above, it's not the PS3 that's doing the downsampling. It's your 768 x 1366 display,

If the resizing is done the proper way, a 768 image would have lessgrain, as the grain pixels merged and blended into each other when the image is "shrunk".

Justt take a 1200 x 1600 grainy picture and resize it properly to 600 x 800 or whatever, if you do it the best way the grain becomes half. Of course you can do it in less than optimal ways too.

[Chad Varnadore]

I believe the problem with the PS3 is its lack of scaling to other resolutions. It should be sending BD at 1080i, scaling to 768p would be done by the display, so any noise or artifacts added in the process would be at the displays end. Most consumer displays can not properly deinterlace 1080i. So, as Deci said, what you're seeing is likely the result of bobbing to 540p and then scaling to 768p. If so, there's a lot you're missing and potentially a good deal of noise being aggravated in the process if not generated. Even good quality scaling will often generate some ringing, which looks like edge enhancement to most.

Should the PS3 implement scaling in the future, there's a good chance it won't support a resolution as esoteric as 768, opting only for the more common 720p instead. If so, should you elect to output at 720p at that time, you'll be adding duplicate processing, which also is a very lossy and potentially noise generating process. By duplicate processing, I mean the interlaced 1080i video, which is how the PS3 extracts the 1080p video on the disc, as it doesn't support full 1080p/24 - at least not at this time - will then be deinterlaced and scaled to 720p, where it'll be routed to the display to be scaled again to the panels native 768p rate.

If so, your only option to preserve more of the detail inherent to the disc and reduce some of the noise you're seeing would be to either get a new display or buy a video processor like those from DVDO or Lumagen that will perform proper inverse telecine for high definition and scale to a greater variety of resolutions like 768p. Upgrading the display would probably be the more cost effective, as the cheapest Lumagen that'll do what you need is around 2k and the cheapest DVDO is 3k. I'm not aware of anything else out that'll handle HD optimally that's any cheaper. However, there's always the chance the the PS3 could support 768p too. There's also the chance of finding an AVR later this year that supports video processing in addition to audio that'll take care of your needs as well. Denon's one manufacturer to keep an eye on for something like that - assuming you think you'll be in the market for a new AVR to take advantage of the PS3s HDMI 1.3 capability.

Sorry for throwing so much at you. I imagine it's a bit to take in. Maybe if they ever get all the kinks worked out of HDMI, one day things will be simple again.

[Deciazulado]

I think the PS3 when it gets scaling abilities it might be able to do 720p in the following signal path:

1080 x 1920 24p content -> add 3:2 repeats -> 1080 x 1920 60p -> downscale to 720 x 1280 60p

1080 x 1920 60i content -> deinterlace -> 1080 x 1920 60p -> downscale to 720 x 1280 60p


The paths in blue would be the new abilities. Right now it has be doing the "1080 x 1920 24p -> add 3:2 repeats -> 1080 x 1920 60p" part because it outputs 1080 x 1920 60p while 60i material remains 60i interlaced.


Also then it would do

720 x 1280 60p content -> upscale to 1080 x 1920 60p


same for 480 i,p content, etc etc

We'll see...


In the current situation the player sends a 1080 x 1920 60Hz interlaced output from both film and 60i content for displays that only accept 1080i, and the display has to deal (deinterlace/scale) with that.

As Chad mentioned going 1080 -> 720 -> 768, or 1080 -> 540 -> 720, or 1080 -> 540 -> 768, etc has several steps where noise/degradation could happen.
Maybe with the scaling other resolutions might be added. And Zoom for those that don't like black bars...

[CJS234]

Originally Posted by Deciazulado

Maybe with the scaling other resolutions might be added. And Zoom for those that don't like black bars...

Ya I hope so but then again the black bars are due to the aspect ratio and if you zoom it'll mess the video up and faces will look elongated and crap and thats not cool.

[Deciazulado]

No I meant a proportional 1.25x or 1.33x zoom that would make Academy 1.37 and Scope 2.39 films mostly fill the screen (without distortion) for the people that complain about black bars. I didn't mean it was proper (hence the exclamation warning) but it might make some people happy. And other zoom ratios (2x etc) would be nice to examine image details.

[JLaSoul]

I have a 40in samsung tv and am thinking of uprading to a 46 or 52, will getting a bigger tv make some of those real grainy parts in a movie seem less than on a smaller one, i know grain is a part of the movie but I was just wondering. Thanks for anyones info.