Image Scope

1. Usages of Image Scope

When handle image, scope can be used to select pixels to be operated. It is set of conditions to manufacture part of image.

2. Define Scope

Scope is determined by both "Shape Constraints" and "Match Colors List".

2.1 Shape Constraints

  1. "Shape" limits coordinates of pixels.
  2. Option "Shape exclude" means pixels outside the shape.

2.1.1 Whole Image

All pixels of the image.

2.1.2 Rectangle, Circle, Ellipse, Polygon

  1. Drag anchors to adjust shape.
  2. Drag shape to translate it.
  3. Right click image to pop menu of shape.
  4. For polygon, left click image to add points for the polygon.

2.1.3 Matting

  1. Click image to add points into start points for matting.
  2. There are Eight-neighbor Matting and Four-neighbor Matting.

2.1.4 Outline

  1. Select a picture with transparent background and its outline is fetched as "Shape".
  2. Width and height of the outline can be adjusted.

2.2 Match Colors List

  1. Pixels selected by "Shape Constraints" are matched to the colors list.
  2. Option "Color exclude" means not matching any color of the list.

2.2.1 Define Colors List

  1. If colors list is empty, then the result of matching is always true.
  2. To add colors, click button Color to pop palette, or check "Pick color" and click image.

2.2.2 Algorithms of Matching Colors

  1. When difference of two colors, that is called "Color Distance", is less than the threshold, the colors are "matched"
  2. Multiple algorithms can be selected to calculate color distance. Some are more accurate while some are less costed.
  3. Weights can be set for some algorithms. Notice whether they are positive or negative.
  4. When compare an image pixel with colors list, their relationship is "OR", which means result is TRUE when the pixel matches any color in the list.

2.3 Other Options

  1. Background image. Can be any image or empty.
    It does not affect usage of scope. That is, scope defined against an image can be applied to any other image.
  2. Option "Scope exclude" means pixels outside the scope.
  3. Option "Handle transparent".

3. Display Scope

To indicate selected pixels obviously, "masked image" is displayed:

  1. Selected pixels are displayed as their orignial colors.
  2. Unselected pixels are displayed as blending colors in orignial colors, mask color, and mask opacity.
  3. For image mostly in dark colors, suggest light color as mask color.
  4. For image mostly in light colors, suggest dark color as mask color.
  5. Click button "Pop"(CTRL+P) to show source image, selected pixels, and masked image.

4. Manage Scopes

  1. When handle image, conditions of selecting pixels can be saved as scope.
  2. When handle image, saved scope can be applied as conditions to select pixels.
  3. Scopes are saved and managed in tree.