com.sun.jna.platform
Class RasterRangesUtils

java.lang.Object
  com.sun.jna.platform.RasterRangesUtils

public class RasterRangesUtils
extends Object

Methods that are useful to decompose a raster into a set of rectangles. An occupied pixel has two possible meanings, depending on the raster :

• if the raster has an alpha layer, occupied means with alpha not null
• if the raster doesn't have any alpha layer, occupied means not completely black

Author:

Olivier Chafik

RasterRangesUtils

public RasterRangesUtils()

outputOccupiedRanges

public static boolean outputOccupiedRanges(Raster raster,
                                           RasterRangesUtils.RangesOutput out)

Outputs ranges of occupied pixels. In a raster that has an alpha layer, a pixel is occupied if its alpha value is not null. In a raster without alpha layer, a pixel is occupied if it is not completely black.

Parameters:

raster - image to be segmented in non black or non-transparent ranges

out - destination of the non null ranges

Returns:

true if the output succeeded, false otherwise

outputOccupiedRangesOfBinaryPixels

public static boolean outputOccupiedRangesOfBinaryPixels(byte[] binaryBits,
                                                         int w,
                                                         int h,
                                                         RasterRangesUtils.RangesOutput out)

Output the non-null values of a binary image as ranges of contiguous values.

Parameters:

binaryBits - byte-packed binary bits of an image

w - width of the image (in pixels)

h - height of the image

out -

Returns:

true if the output succeeded, false otherwise

outputOccupiedRanges

public static boolean outputOccupiedRanges(int[] pixels,
                                           int w,
                                           int h,
                                           int occupationMask,
                                           RasterRangesUtils.RangesOutput out)

Output the occupied values of an integer-pixels image as ranges of contiguous values. A pixel is considered occupied if the bitwise AND of its integer value with the provided occupationMask is not null.

Parameters:

pixels - integer values of the pixels of an image

w - width of the image (in pixels)

h - height of the image

occupationMask - mask used to select which bits are used in a pixel to check its occupied status. 0xff000000 would only take the alpha layer into account, for instance.

out - where to output all the contiguous ranges of non occupied pixels

Returns:

true if the output succeeded, false otherwise