Fullscreen overlay mode

[dirkdeftly]

fullscreen works...overlay has that same mesh of dots :wierd:

[pure-krypton]

wtf's a bpp? Beat per pixel???


The only difference i could pick up was the colours. Fullscrean overlay, duller colours.
Without fullscrean overlay, brighter colours and sharper viewing but it's a few FPS's slower though

[Zevensoft]

Atero, you're using a 16 bit (or lower ) resolution. Try 24/32 bit instead.

[pure-krypton]

Is it posible to edit someone elses message?

[Magic.X]

Use the Button to edit your posts (should work for 3 hours after the post has been made). Of course you can NOT edit others Messages.

[pure-krypton]

I know ho to edit my messages, but I wasn't sure if you could edit someone elses messages. I would had some fun if that was possible. Oh well

[Deamon]

*sigh*, the misunderstandings afterwards would be so extremely big, you could have figured that out yourself, right?

[Magic.X]

Originally posted by Zevensoft
Atero, try 24/32 bit

Did this help?

[Deamon]

I guess 24 won't. Though 32 might, since AVS is originally calculated in 32bit. Every other setting has to be recalculated and therefor slower.

[UnConeD]

In case you're wondering what overlays are, here's the deal... when you're playing video on the screen, it has to be updated a lot. But in effect, it's only one small area that is updated, and it's located somewhere in the center of the screen (windowed) or all over the place (full-screen). That's quite memory/cache intensive.

So someone thought of overlay mode: rather than doing all the copying in software, just put the video in a separate buffer, and let the videocard draw it as it sends the image to your monitor. After all, a video card is continuously scanning over the image anyway as it sends it to your monitor, so doing a simple switch between video and regular screen at the appropriate pixels is no big deal. On top of that, the video-card can scale/stretch the image very fast, because that sort of stuff can be put into silicon at no cost.

Unfortunately, there's the problem that in a windowed system, the video-area can be partially (or wholly) occluded. There's no easy way to get this info from windows, and even if you could, building support for irregularly shaped viewports for overlay would defeat the whole point because then the videocard would need a lot of extra logic too.

So, they use colorkeying: the video-area is filled with an uncommon, unique color, and the overlay is only drawn inside the designated viewport and when the color in the framebuffer (the 'screen') matches the color-key.

Now fullscreen overlay mode. Normally, going fullscreen required a resolution change, because otherwise the stretching would be done in software, which is either slow (bilinear) or ugly (point). Plus it wouldn't be able to handle arbitrary sizes anyway. So mediaplayers use the overlay functionality for the entire screen. This has some advantages:

- Bilinear filtering is done for free
- No resolution change is required
- Arbitrary sizes are allowed (though not in AVS)

Unfortunately, the overlay buffer's format is not RGB I believe, but YUV or a similar one. YUV or YCrCb stores the color as a brightness 'Y' plus a redness/blueness factor. It's halfway between HSL and RGB.
Interpolating in YUV gives you great results for natural photos and film, but looks like crap for computer generated stuff because the color can bleed at sharp edges.

As far as grabbing the image from the hDC, that would be very slow on Windows. I'm pretty sure AVS just creates a 32-bit DIBs (CreateDIBSection) and uses the returned pointer to directly read/write to the bitmap's pixels.

[dirkdeftly]

d00d...that is so not cool...one of my m$ games musta set my mon to 16 bit while i was looking >_< yea it did help get rid of that mesh, thanks

[Deamon]

Now that certainly cleared some things up over here, thanks UnConeD.

[Magic.X]

UnConeD = Computer Encyclopedia

Thank ya!

[Deamon]

lol, yep, that's a pretty accurate description.