Focus Blur Plug-in

Top page (Japanese) Message board Focus Blur Plug-In | Japanese

## Applying depth effect

I have proposal about making depth of field and other techniques with this plug-in. also I'm explaining what is problem. if you are interested, please see below.

### Depth map

Use depth map, and do not use selection as blurring intensity, If you expect depth effect. It's easy, just make a new layer or channel.

using selection | using depth map
Could be shown tow images, blurred and clear. | It makes intensity of blur.

### Depth precedence

Use depth precedence, if depth map has separated layer clearly.

There is failing case with complicated depth map. Consider to split a layer when you couldn't get quality.

without precedence | with precedence
There is confused effect, focusing and blurring are mixed. | Objects are given independent distance by separated effect.

### Evade anti-alias

If depth map has anti-alias, it can makes dotted noise because small dots can be focused.

Evade anti-alias option is prepared as easy way for this problem.

Source image | with depth precedence | evade anti-alias
The figure drawed by ellipse selection tool is used for source and depth. | Anti-aliased pixels have been focused with medium focal distance. | It is focused normally.

## Changing blurring radius

I'm figuring what problem is caused by changing blurring radius.

First of all, I present an easy model of blurring. an image is black and white, and it has enough space around. A part of the image is sloped uniformly. Blurring radius is not changed in first time. Z axis of cube means amount of pixel, but it is constant in this condition.

Next, Try to make a changing blurring width. Blur the white and keep the black. Amount of pixel doesn't stay constant when blurring width is changed. It is normalized for returning to color, then the kept black has been eroded by the white.

Also, amount of pixel is not enough in the part of white before it is normalized. It means sample is not enough in the part. same as blurring width is narrow. that is not completely blurring.

If the area of black and white has picture, the white area will be blurred, and the black area will not be blurred, but it shows not enough blurring and little blurring about border. It is reversed, and it caused strange edge.

It might be correct, but what do you want? If the scene has a relation of before and behind, you could give some process regarding it as a rendering model.

A feature called depth precedence directs to process with a relation of before and behind for this phenomenon.

foreground covers background at first. Just focused area shuts behind completely.

It is filled by pixels that is remade with constant blurring width except foreground, in area where didn't reach to amount of pixel for one pixel.

Another case, foreground is blurred.

It is been closing in order from foreground while it doesn't reach to amount of pixel for one pixel. like a alpha composition so it shuts non-blurred area. It is cut down in where get over the one pixel. Therefore the sum total is not normalized.

It is same about filling amount of pixel for it's not enough. Background wouldn't be blurred, but this is only way because behind of foreground is empty in 2D picture.

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