ImageMagick – MagickCore, C API: Paint on an Image
Author: ImageMagick Studio LLC
Description: ImageMagick is a powerful, open-source software suite for creating, editing, converting, and manipulating images in over 200 formats. Ideal for web developers, graphic designers, and researchers, it offers versatile tools for image processing, including batch processing, format conversion, and complex image transformations.
Keywords: MagickCore, C API: Paint on an Image, Image Processing, Digital Image Editing, Image Conversion, Open-Source Software, Image Manipulation, Command-Line Image Tools

# Paint

## FloodfillPaintImage

FloodfillPaintImage() changes the color value of any pixel that matches target and is an immediate neighbor. If the method FillToBorderMethod is specified, the color value is changed for any neighbor pixel that does not match the bordercolor member of image.

By default target must match a particular pixel color exactly. However, in many cases two colors may differ by a small amount. The fuzz member of image defines how much tolerance is acceptable to consider two colors as the same. For example, set fuzz to 10 and the color red at intensities of 100 and 102 respectively are now interpreted as the same color for the purposes of the floodfill.

The format of the FloodfillPaintImage method is:

    MagickBooleanType FloodfillPaintImage(Image *image,
      const ChannelType channel,const DrawInfo *draw_info,
      const MagickPixelPacket target,const ssize_t x_offset,
      const ssize_t y_offset,const MagickBooleanType invert)

A description of each parameter follows:

image
  the image.
channel
  the channel(s).
draw_info
  the draw info.
target
  the RGB value of the target color.
x_offset,y_offset
  the starting location of the operation.
invert
  paint any pixel that does not match the target color.

## OilPaintImage

OilPaintImage() applies a special effect filter that simulates an oil painting. Each pixel is replaced by the most frequent color occurring in a circular region defined by radius.

The format of the OilPaintImage method is:

    Image *OilPaintImage(const Image *image,const double radius,
      ExceptionInfo *exception)

A description of each parameter follows:

image
  the image.
radius
  the radius of the circular neighborhood.
exception
  return any errors or warnings in this structure.

## OpaquePaintImage

OpaquePaintImage() changes any pixel that matches color with the color defined by fill.

By default color must match a particular pixel color exactly. However, in many cases two colors may differ by a small amount. Fuzz defines how much tolerance is acceptable to consider two colors as the same. For example, set fuzz to 10 and the color red at intensities of 100 and 102 respectively are now interpreted as the same color.

The format of the OpaquePaintImage method is:

    MagickBooleanType OpaquePaintImage(Image *image,
      const PixelPacket *target,const PixelPacket *fill,
      const MagickBooleanType invert)
    MagickBooleanType OpaquePaintImageChannel(Image *image,
      const ChannelType channel,const PixelPacket *target,
      const PixelPacket *fill,const MagickBooleanType invert)

A description of each parameter follows:

image
  the image.
channel
  the channel(s).
target
  the RGB value of the target color.
fill
  the replacement color.
invert
  paint any pixel that does not match the target color.

## TransparentPaintImage

TransparentPaintImage() changes the opacity value associated with any pixel that matches color to the value defined by opacity.

By default color must match a particular pixel color exactly. However, in many cases two colors may differ by a small amount. Fuzz defines how much tolerance is acceptable to consider two colors as the same. For example, set fuzz to 10 and the color red at intensities of 100 and 102 respectively are now interpreted as the same color.

The format of the TransparentPaintImage method is:

    MagickBooleanType TransparentPaintImage(Image *image,
      const MagickPixelPacket *target,const Quantum opacity,
      const MagickBooleanType invert)

A description of each parameter follows:

image
  the image.
target
  the target color.
opacity
  the replacement opacity value.
invert
  paint any pixel that does not match the target color.

## TransparentPaintImageChroma

TransparentPaintImageChroma() changes the opacity value associated with any pixel that matches color to the value defined by opacity.

As there is one fuzz value for the all the channels, the TransparentPaintImage() API is not suitable for the operations like chroma, where the tolerance for similarity of two color component (RGB) can be different, Thus we define this method take two target pixels (one low and one hight) and all the pixels of an image which are lying between these two pixels are made transparent.

The format of the TransparentPaintImage method is:

    MagickBooleanType TransparentPaintImage(Image *image,
      const MagickPixelPacket *low,const MagickPixelPacket *hight,
      const Quantum opacity,const MagickBooleanType invert)

A description of each parameter follows:

image
  the image.
low
  the low target color.
high
  the high target color.
opacity
  the replacement opacity value.
invert
  paint any pixel that does not match the target color.