In the raster editing library, we base our algorithms on raster vector conversion. Raster vector conversion algorithms.
As specific algorithms in the raster editing library:
  1. Fast labeling algorithm
    2. The fast labeling algorithm is also used in OCR. It extracts shapes from monochrome raster images and labels them. Our labeling process performs over 10 times faster than the commonly used one.

    4096×4096 pixels
    1024 blobs (connected areas subject to labeling) image
    Measured with Core i3 2.13GHx
    OpenCV labeling × 1000 times 134 seconds
    Our library's labeling with ngkocr4.dll × 1000 times 12 seconds

    Line shapes that intersect at intersections are extracted as separate labeled shapes for each line. The raster below the intersection does not disappear even with shape deletion or movement because it is shared by the intersecting line labeled shapes.
  2. Bresenham's algorithm
    3. When drawing lines, rectangles, circular arcs, or elliptical arcs of arbitrary size and shape, we use the Bresenham's algorithm.
  3. Scanline conversion
    4. We use the scanline conversion algorithm to fill the interior of polygons in various situations such as initialization or drawing.