5.13. Razširi vrednost

5.13.1. Pregled

Slika 17.78. Example for the Value Propagate filter

Example for the Value Propagate filter

Izvirnik

Example for the Value Propagate filter

Filter Value Propagate applied


This filter works on color borders. It spreads pixels that differ in a specified way from their neighboring pixels.

5.13.2. Aktiviranje filtra

This filter is found in the image window menu under FiltersDistortsValue Propagate….

5.13.3. Možnosti

Slika 17.79. Value propagate filter options

“Value propagate” filter options

Presets, Preview, Split view
[Opomba] Opomba

These options are described in Razdelek 2, “Common Features”.

Način

The examples will be about the following image:

Več beline (večja vrednost)

Pixels will be propagated from upper value pixels towards lower value pixels. So bright areas will enlarge.

Slika 17.80. Več beline

Več beline

Bright pixels have been propagated to dark pixels in the four directions : top, bottom, right and left. Filter applied several times to increase effect.


Več črnine (manjša vrednost)

Pixels will be propagated from lower value pixels towards upper value pixels. So dark areas will enlarge.

Slika 17.81. Več črnine

Več črnine

Slika 17.82. To bottom only

To bottom only

The same as above with To bottom direction only checked.


Srednja vrednost v vrhove

On a border between the selected thresholds, the average of both values is propagated.

Slika 17.83. Srednja vrednost v vrhove

Srednja vrednost v vrhove

A thin border with a transitional color has been added to objects. It is not visible around objects with smoothed borders.

Srednja vrednost v vrhove

Green area zoomed x800. A thin border (one pixel wide) has been added. Its value is the average between grey (90%) and green (78%) : (90 + 78) / 2 = 84.


Color to peaks

The propagated areas will be filled with the foreground color of the toolbox.

A color selector opens, with a color picker.

Slika 17.84. Color to peaks

Color to peaks

In this example, the selected color is Red. A thin border, one pixel wide, red, is added around objects. With smoothed objects, this border is located at the furthest limit of smoothing. Here, another border appears inside. This is an artifact due to the small size of the object which makes the smoothing area of opposite sides to overlap.


Only color

Only areas with the selected color will propagate. With this option, soft and fuzzy edges don't propagate well.

Slika 17.85. Only color

Only color

In this example, the selected color is that of the green object. After applying filter several times, the green area is clearly enlarged.


Bolj prekrivno, Bolj prosojno

These commands work like More white and More black. Opaque (transparent) areas will be propagated over less opaque (transparent) areas. These commands need an image with an alpha channel.

Slika 17.86. Bolj prekrivno

Bolj prekrivno

Original layer, with a transparent background.

Bolj prekrivno

Filter applied several times: the green, opaque, area got increased.


Nižji prag, Višji prag

A pixel will be propagated (spread) if the difference in value between the pixel and its neighbour is no smaller than the lower threshold and no larger than the upper threshold.

Hitrost razširjanja

That's the propagating amount. The higher it will be the more colored the propagation will be.

Na vrh, Na levo, Na desno, Na dno

You can select one or more directions.

Razširjanje kanala vrednosti

If checked, the pixel's color channels (gray channel on grayscaled images) will be propagated. The option is checked by default, of course.

Razširjanje kanala alfa

If checked, the pixel alpha value will be propagated, otherwise the pixel will get the alpha of the neighboring pixels.

Clipping

The result of this filter can be larger than the original image. With the default Adjust option, the layer will be automatically resized as necessary when the filter is applied. With the Clip option the result will be clipped to the layer boundary.

5.13.4. Using Value Propagate

Left: Original........Middle: More white........Right: More black