Codecs to upscale DVD, DivX and Live TV (1 Viewer)

Spragleknas

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    ^ Indeed!
    You should always (if possible) use the native resolution of the LCD, to avoid scaling.
    Also: Upscaling to a higher resolution than your LCD can handle is just silly, as it will (ofc) be downscaled (by TV or vid. card) resulting in even lower quality.

    The goal is do do as few scaling operations as possible, and make the sure the scalings that are done is of the best possible quality.
     

    hulkhaugen

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    Unless you are sending a picture 1:1, you are doing scaling.
    IOW, if you are playing SD material on a HD screen, then scaling is done (if it covers >50 % of the screen). Since it makes scales to a bigger resolution, it is upscaling.

    Conclusion: You are probably always upscaling (unless playing 1080p material on a "HD-ready" screen - in which case you are downscaling). The question is what the quality of the scaling is, and if it is done by CPU/software or only videocard. For normal STB users, scaling is done by STB or TV, depending in input and TV resolution.

    ok, so what i'm doing is upscaling to 720p with software (windows/ati?), and then upscaling it to 1080p with my LCD?

    Why are you running at 1280 x 720 when you have a full-HD resolution (1920 x 1080p) TV ? - this will result in SD material being upscaled by the video card to 1280 x 720, then upscaled a second time by the TV to 1920 x 1080 (the LCD panel resolution).

    High-quality FFDshow upscaling takes a lot of CPU power (particularly if you need de-interlacing as well), and putting FFDshow in the path will also break DXVA hardware acceleration.

    Tony

    Well, the obvious reason is that i'm not able to read what's on the tv (internet sites etc), my desktop look like crap, and even worse if i try to rise the dpi. Is there more tweaks to the dpi settings to make it look like it does with a lower resolution? Sittin' 3 meters away from a 52", but 1080 makes tings too small, 720 feels about right....

    Isn't DXVA only used for HD material, like H.264?

    ^ Indeed!
    You should always (if possible) use the native resolution of the LCD, to avoid scaling.
    Also: Upscaling to a higher resolution than your LCD can handle is just silly, as it will (ofc) be downscaled (by TV or vid. card) resulting in even lower quality.

    The goal is do do as few scaling operations as possible, and make the sure the scalings that are done is of the best possible quality.

    Well, the reason why i'm asking about this is because it's recommended in the "official guide", explaining that the result will be a smoother look after downscaling the overupscaled picture... I also feel skeptical about this one, considering unnecessary use of cpu/gpu power...

    And where does ATI AVIVO fit in to this picture?
     

    Spragleknas

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    ok, so what i'm doing is upscaling to 720p with software (windows/ati?), and then upscaling it to 1080p with my LCD?
    Correct :)

    Isn't DXVA only used for HD material, like H.264?
    Nope, also for SD.

    Well, the reason why i'm asking about this is because it's recommended in the "official guide", explaining that the result will be a smoother look after downscaling the overupscaled picture... I also feel skeptical about this one, considering unnecessary use of cpu/gpu power...

    And where does ATI AVIVO fit in to this picture?
    Well, I'm quite certain that a correctly scaled picture would be best if no scaling is done after the upscaling.

    Logically, I think the best would be:
    Video w/resolution-X ---- PC upscaling to 1920x1080p ---> TV w/resolution 1080p === ONE scaling processes

    The way you have it now, best is probably:
    Video w/resolution-X ---- PC upscaling to 1280x720p ----> TV upscaling to 1920x1080 === TWO scaling processes

    What you are doing now:
    Video w/resolution-X ---- PC upscaling to 2880x1620 + gfx downscaling to 1280x720p --> TV upscaling to 1920x1080 === THREE scaling processes

    Now, I sincerely think your "hunt for best PQ" is somewhat waste of time unless you set the output to 1920x1080.
    :sorry:

    And where does ATI AVIVO fit in to this picture?
    HUH?


    PS:

    Unscaled image:
    bridge.jpg

    Same image, but after scaling (here due to lack of 1:1)
    bridge-scaled-2.jpg

    Source: http://pixelmapping.wikispaces.com/Pixel+mapping+explained
     

    hulkhaugen

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    Ok, thanks for good reply. I want to use my native resolution which is 1920x1080, but as i mentioned earlier, it's impossible to read from websites then. icons, menubars, text in general looks so small. And if i increase the dpi, they look like they're on steroides, bold and ugly. Ppl would think i've bad eyes.

    You wouldn't happen to know about a guide on how to make 144(or 120)dpi look like 96dpi, just zoomed in?

    And yeah, ATI AVIVO, it's something similar to Nvidia PureVideo afaik. Don't know what it does, but i think it has something to do with gpu acceleration and adding some filters to increase the image quality. I've never got myself around to fiddle with it...
     

    rtv

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    Ok, thanks for good reply. I want to use my native resolution which is 1920x1080, but as i mentioned earlier, it's impossible to read from websites then. icons, menubars, text in general looks so small.

    What you realize is that FullHD doesn't make any sense on common TVs or even less than 32" LCDs (from a normal viewing distance).

    With my projector at > 100" everything is just big enough for a comfortable reading - go figure...

    Here's a nice chart for a better orientation:
    CarltonBale.com 1080p Does Matter - Here's When (Screen Size vs. Viewing Distance vs. Resolution)

    P.S. of course it makes perfectly sense to buy e.g. a 22" LCD capable of FullHD if you want to use it as "control device" in clone mode.
     

    hulkhaugen

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    Ok, thanks for good reply. I want to use my native resolution which is 1920x1080, but as i mentioned earlier, it's impossible to read from websites then. icons, menubars, text in general looks so small.

    What you realize is that FullHD doesn't make any sense on common TVs or even less than 32" LCDs (from a normal viewing distance).

    With my projector at > 100" everything is just big enough for a comfortable reading - go figure...

    Here's a nice chart for a better orientation:
    CarltonBale.com 1080p Does Matter - Here's When (Screen Size vs. Viewing Distance vs. Resolution)

    P.S. of course it makes perfectly sense to buy e.g. a 22" LCD capable of FullHD if you want to use it as "control device" in clone mode.

    Well, i have a 52" at ~3m distance. But 720p won't look as good as 1080p, mainly because of the scaling, not the resolution itself imo. But let's say i stick to 720p, should i then upscale the image with ffdshow to 720p or 1080p? Does windows scale the image to output resolution before or after the postprocessing by ffdshow?
     

    Owlsroost

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    For video, the scaling is done by the video card hardware - so it's the last thing in the processing chain.

    Why not run MP via a batch file, with a command preceeding the MP command to change the screen resolution to 1920 x 1080 ?

    Tony
     

    tourettes

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    Well, i have a 52" at ~3m distance. But 720p won't look as good as 1080p, mainly because of the scaling, not the resolution itself imo. But let's say i stick to 720p, should i then upscale the image with ffdshow to 720p or 1080p? Does windows scale the image to output resolution before or after the postprocessing by ffdshow?

    If you are ignoring the native resolution of the display you are already messing up the picture so badly that it doesn't matter if you scale the picture on PC side with ffdshow or let the GPU handle it. Actually the best results might be in that case to downscale to the half of the original 1080p resolution.
     

    tourettes

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    Why not run MP via a batch file, with a command preceeding the MP command to change the screen resolution to 1920 x 1080?

    That would be the best sollution. I.e. text would be readable in desktop and videos would be scaled only once.
     

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