Are people able to do this compositing in HDR?
I.e., do you have the background plates in HDR, and do you access to a program that can do the blend operation on HDR images.
I'm guessing probably not
Alpha render?
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v_mulligan
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v_mulligan
- Posts: 126
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Then, do you store the colour of each pixel (based on the samples already collected) and the number of samples colouring that pixel? Sorry to keep guessing at how Indigo works on the inside 
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If you stored that information, I'd guess you'd modify the colour of a given pixel as new samples are collected by taking a weighted average of that pixel's colour and the colour of the current sample. For example, if a pixel was red based on five samples, and a sixth sample had just been taken that returned yellow, the new colour of the pixel would be 5/6*(red) + 1/6*(yellow).
If this is the case, store an alpha value with each pixel (increasing memory costs by 33%). Store the number of NON-BACKGROUND samples affecting the colour of the pixel. Modify the colour value only if the new sample is not a background sample. Modify the alpha component by taking a weighted average of the current alpha value and a boolean value representing whether the new sample is background or not.
.If you stored that information, I'd guess you'd modify the colour of a given pixel as new samples are collected by taking a weighted average of that pixel's colour and the colour of the current sample. For example, if a pixel was red based on five samples, and a sixth sample had just been taken that returned yellow, the new colour of the pixel would be 5/6*(red) + 1/6*(yellow).
If this is the case, store an alpha value with each pixel (increasing memory costs by 33%). Store the number of NON-BACKGROUND samples affecting the colour of the pixel. Modify the colour value only if the new sample is not a background sample. Modify the alpha component by taking a weighted average of the current alpha value and a boolean value representing whether the new sample is background or not.
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v_mulligan
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Some people might be. I'd probably be compositing in Photoshop CS, using 8-bit channels. While I know total physical accuracy is a major goal in Indigo, I like twiddling things in post, even if they cease to be 100% physically accurateOnoSendai wrote:So another question arises:
Are people able to do this compositing in HDR?
I.e., do you have the background plates in HDR, and do you access to a program that can do the blend operation on HDR images.
I'm guessing probably not
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ViennaLinux
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if its OPTIONAL then its okay but I think rendering beautiful scenes is already very memory intensive. Okay people are upgrading slowly to 4 gb of RAM but on some render servers there are only 1024 mb.OnoSendai wrote:Ok, I've thought of one way.
It would involve two master buffers; I wonder if using 2x the amount of memory for the buffer than usual will be alright for people?
Core2duo e6600 @ 3.1GHz watercooled at default VCore ^^
dude... please don't cry...ViennaLinux wrote:people are upgrading slowly to 4 gb of RAM but on some render servers there are only 1024 mb.
but there will always be guys in with a longer Dong... but 1024 for a server is really something to laugh about
Please don't slow development, because you won't spend 25 bucks for some Hardware...
polygonmanufaktur.de
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ViennaLinux
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he he.. I only hear from my parents, if THEY need money...ViennaLinux wrote:you mean because my linux server will still run with 32 mb of system memory or because you get a sun server with 64 GB RAM paid by your parents
and I'm not talking about buying 64GB of RAM dude... only some extra 1024MB... (thats about 1/60 of that you are proposing) this is no money... stop smoking for a week, or stay at home a weekend and don't go party... come one you can't compare this... see my system specs for details about my wealthy spenders...
polygonmanufaktur.de
Just my worthless two cents and a few personal opinions here.
First I don't like the idea of alpha compositing too much. As Ono already said, in 90 per cent of the time, it will not feel realistic because of the lack of reflections at grazing angles. Assuming you're not lighting your scene with an HDR version of your back plate, it will look even worse. This is no trivial issue. In an interior with a back plate of the sea showing through the window, you really want to see the sea reflected on the glossy table. Your eye won't believe the picture if you don't.
Another problem is that most of the time, you get screwed perspective lines. What I'm trying to say here is that if you have an image taken with a 50mm lens and try to use as backdrop to an interior scene using a 28mm lens, it will just look silly. But if you apply your image on a plane in Blender and give it a bit of emission (textured emitter), you will achieve a far better result with the ability to move your image, zoom it in or out, to get the perspective lines aligned. The overall grain will also be a lot more homogenous.
Basically, my very own personal opinion here is that I'd rather see displacement than alpha channel rendering any day. Now if you're talking about something that would eventually give us some kind of a multilight equivalent, that's a completely different story. THAT would be something.
First I don't like the idea of alpha compositing too much. As Ono already said, in 90 per cent of the time, it will not feel realistic because of the lack of reflections at grazing angles. Assuming you're not lighting your scene with an HDR version of your back plate, it will look even worse. This is no trivial issue. In an interior with a back plate of the sea showing through the window, you really want to see the sea reflected on the glossy table. Your eye won't believe the picture if you don't.
Another problem is that most of the time, you get screwed perspective lines. What I'm trying to say here is that if you have an image taken with a 50mm lens and try to use as backdrop to an interior scene using a 28mm lens, it will just look silly. But if you apply your image on a plane in Blender and give it a bit of emission (textured emitter), you will achieve a far better result with the ability to move your image, zoom it in or out, to get the perspective lines aligned. The overall grain will also be a lot more homogenous.
Basically, my very own personal opinion here is that I'd rather see displacement than alpha channel rendering any day. Now if you're talking about something that would eventually give us some kind of a multilight equivalent, that's a completely different story. THAT would be something.
Hi BbB,
I guess the kind of stuff it will be useful for is architectural work like
http://www.indigorenderer.com/joomla/in ... emId=10325
In this kind of case there may not be a lot of grazing angle specular reflections, but compositing by hand would be a pain.
I guess the kind of stuff it will be useful for is architectural work like
http://www.indigorenderer.com/joomla/in ... emId=10325
In this kind of case there may not be a lot of grazing angle specular reflections, but compositing by hand would be a pain.
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