This class has no public fields and methods and is used to identify average interpolation by itself in image processing functions.

ImGearInterpolationOptions

A Bayer dithering algorithm is used to reduce the number of colors (or shades of gray) in the image. Note that setting the output channel depth to 1 will reduce the image to monochrome or black-and-white. Also, the output channel depth must be less than the input channel depth, or an error will result.

ImGearBilinearInterpolationOptions

ImGearBicubicInterpolationOptions

Bitonal reduction reduces an image to black and white by comparing each pixel to a threshold value. Several modes, defined in ImGearBitonalReductionModes, are available for determining how the red, green, and blue color components of a pixel contribute to its brightness when compared to the threshold value.

If you set Mode to ImGearBitonalReductionModes.WEIGHTED, you may also set the values of Weight1, Weight2, and Weight3. These "weights" are used to determine how much influence the values of the red, green, or blue pixels will have on the reduction. For example, if Weight1 (red) = 255, Weight2 (green) = 0, Weight3 (blue) = 0, the whole reduction will depend on the value of the red pixels. The green and blue pixel values will have "no weight."

Setting Mode to ImGearBitonalReductionModes.GRAYSCALE gives the most weight to the value of green. This optimizes for the perception of the human eye, in which blue is the hardest color to see, and therefore requires the least weight.

A Mode of ImGearBitonalReductionModes.AVERAGE gives equal weight to all three pixel values.

Here are the formulas used by the three different reduction methods:

• GRAYSCALE: value = (red*77 + green*151 + blue*28)/256;
• AVERAGE: value = (red + green + blue)/3;
• WEIGHTED: value = (red*w1 + green*w2 + blue*w3)/(w1 + w2 + w3);

Use the Threshold option to set the threshold value for converting pixels to black or white. If the value, as calculated by one of the above reduction methods, is less than Threshold, the pixels will be set to black; if it is greater than or equal to Threshold, the pixels will be set to white.

ImGearInterpolationOptions

Diffuse reduction reduces an image to either black and white or 4bpp color by performing dithering according to a threshold. The type of dithering used is known as error diffusion, which attempts to spread out error (the difference in color between input and output pixels) across a two dimensional space in the output image.

A threshold value of 128 will produce an output image in which black and white are in equal proportion. A value greater than 128 would mean more bright than dark, and a value less than 128 would mean more dark than bright.

When reducing to 4bpp, a palette containing colors to use for the output image can optionally be specified. If this palette is not supplied, a default palette will be used.

This class defines interpolation options for scale-to-gray interpolation.

ImGearInterpolationOptions

Halftone reduction reduces an image to black and white in such a way that it is suitable for half-toning. The resulting image will consist of small squares of varying sizes that will give the appearance of varying shades of gray.

Use the base class for interpolation modes that do not need additional options. Use derived classes to pass specific options. If a base class is passed for a mode that has a derived class, the default option values are used.

Median cut reduction reduces an image to 8bpp by dividing it into a number of equally sized squares. The number of squares is equal to the number of desired output colors. The colors of the pixels in each square will be averaged to produce a resulting color. The resulting image will contain only these colors.

This class has no public fields and methods and is used to identify nearest neighborhood interpolation by itself in image processing functions.

ImGearInterpolationOptions

This class has no public fields and methods and is used to identify interpolation by itself in image processing functions.

ImGearInterpolationOptions

Octree reduction reduces an image to 4bpp or 8bpp by repeatedly subdividing cubic representations of the RGB color space according to image content.

Popularity reduction reduces an image to 8bpp while retaining its most popular, or prevalent, colors. Use the maxColors field option to specify the maximum number of colors wanted in the result.

ImGearInterpolationOptions

ImGearInterpolationOptions

This class does not have a public constructor because all its functionality is implemented through static members.

ImGearProcessingVerifier

These methods should be used to distinguish a sub-set of pages for which a particular filter is applicable.

ImGearProcessing

This is the main class for all image raster processing operations.

Note: These methods should be used to distinguish a sub-set of pages for which particular filter is applicable; e.g., canApplyGaussianBlur method returns true only if incoming page image is not binary, that is BitDepth > 1. Parameters of all IP functions are checked separately.

The only options used by the ImGearRasterProcessing.reduce method are the ones which correspond to the type of reduction as specified by the reductionMethod parameter of the ImGearRasterProcessing.reduce method.

This class defines reduction options for scale reduction. Scale reduction can be performed on an image whose color space is anything but indexed. The output image will always have the same color space as the input image. It works by linearly scaling the component values for each pixel to the desired output depths. For example, you could reduce a 24bpp (8-8-8) RGB image to 16bpp (5-6-5) RGB. Simply specify the desired output channel depths (and color space) in the parameters for the reduce method.

Note: You can set dontScalePixels option to true to avoid scaling the pixel values. In this case, the component values of each pixel will be preserved (within the limits of precision) even though their effective ranges may be different.

This interface declares one method processPixel which must be implemented by the user.

Please, see ImGearBitonalReductionOptions class reference.

These values are passed to the com.accusoft.imagegear.core.ImGearChannelRange structure constructor.

See ImGearHalftoneReductionOptions class description for more details.

For example, if you set ARITH_ADD merge method, the resulting pixel values (of those pixels that intersected from the two images) equal the sum of the value of the pixel in the original image and the value of pixel in the image being merged.