Syntax
Visual Basic
C#
Managed Extensions for C++
C++/CLI
Parameters
- page
- Image to reduce bit depth.
- colorSpace
- Color space to reduce image to.
- channelDepths
- Channel depths to reduce image to.
- reductionMethod
- Method to use for reducing bit depth.
- options
- Options to use for reduction, or set to null to use defaults.
Remarks
All methods except for ImGearReductionMethods.SCALE change the color space of the image to Indexed.
ImGearReductionMethods.SCALE does not change the image's color space, but only scales the channel depths. Different reduction methods have their own options, which can be set using the options parameter.
For more information about a particular method, see its options. The following reduction methods are available in ImGearReductionMethods:
| Method | Input color spaces and bit depths | Output color spaces and bit depths | Options |
|---|---|---|---|
| BAYER | RGB (24)Grayscale (8)Indexed (>1) | Indexed (1 or 4) | ImGearBayerReductionOptions |
| BITONAL | RGB (24)Grayscale (8)Indexed (>1) | Indexed (1) | ImGearBitonalReductionOptions |
| DIFFUSE | RGB (24)Grayscale (8)Indexed (>1) | Indexed (1 or 4) | ImGearDiffuseReductionOptions |
| HALFTONE | RGB (24)Grayscale (8)Indexed (>1) | Indexed (1) | ImGearHalftoneReductionOptions |
| MEDIAN | RGB (24)Grayscale (8) | Indexed (8) | ImGearMedianCutReductionOptions |
| OCTREE | RGB (24)Grayscale (8) | Indexed (4 or 8) | ImGearOctreeReductionOptions |
| POPULARITY | RGB (24)Grayscale (8) | Indexed (8) | ImGearPopularityReductionOptions |
| SCALE | Any color space except Indexed | Same color space as input | ImGearScaleReductionOptions |
Example
| C# |  Copy Code |
|---|---|
// Reduce the bit depth of an image to 4 bit // Create reduction options object and setup a few values for a 16 color 4-bit reduction. ImGearReductionOptions igReductionOptions = new ImGearReductionOptions(); igReductionOptions.Octree.MaxColors = 16; igReductionOptions.Octree.FastRemap = false; igReductionOptions.Octree.ErrorDiffusion = true; //Apply the reduction using Octree to get a 4-bit index image. ImGearRasterProcessing.Reduce(igRasterPage, new ImGearColorSpace(ImGearColorSpaceIDs.I), new int[] { 4 }, ImGearReductionMethods.OCTREE, igReductionOptions); | |
| Visual Basic | Copy Code |
|---|---|
' Reduce the bit depth of an image to 4 bit ' Create reduction options object and setup a few values for a 16 color 4-bit reduction. Dim igReductionOptions As New ImGearReductionOptions() igReductionOptions.Octree.MaxColors = 16 igReductionOptions.Octree.FastRemap = False igReductionOptions.Octree.ErrorDiffusion = True 'Apply the reduction using Octree to get a 4-bit index image. ImGearRasterProcessing.Reduce(igRasterPage, New ImGearColorSpace(ImGearColorSpaceIDs.I), New Integer() {4}, _ ImGearReductionMethods.OCTREE, igReductionOptions) | |
