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DifferenceImage_Flex

Computes the non-negative distances between corresponding pixel values using tiles.

Name	Type	Range	Description
inImage1	Image		First input image
inImage2	Image		Second input image
inTileWidth	Integer	1 -
inTileHeight	Integer *	1 -
inTileTranslationMode	TileTranslationMode
outImage	Image		Output image

Applications

Useful for things like comparing an image against a template or for detecting differences between consecutive video frames.

Description

The operation computes the absolute difference between images. First the input images are divided into tiles. Each tile is then considered separately. It is translated by a minimal vector in one of the number of directions (depending on inTileTranslationMode, 4 or 8) and the translation with minimum overall difference between input images in this tile is considered to be the proper one. Finally, the output image values in the tile are computed using the so computed translation and the same formula like in DifferenceImage_Shifted.

In multichannel (color) images each pixel channel is processed separately.

The operation requires that the images being processed have equal format and dimensions, otherwise an error with appropriate description occurs. To obtain an image of desired dimensions one can use ResizeImage or CropImage filter. To alter the pixel type of an image one can use ConvertPixelType filter. ConvertToMultichannel and AverageChannels filters allow to alter the number of image channels.

Examples

DifferenceImage_Flex performed on the sample images with inTileWidth = inTileHeight = 16 and inTileTranslationMode = EightDirections.

Errors

This filter can throw an exception to report error. Read how to deal with errors here: Error Handling

Error type	Description
DomainError	Image sizes are not equal in DifferenceImage_Flex.
DomainError	Image formats are not the same in DifferenceImage_Flex.

Complexity Level