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DownsampleImage

Module:	FoundationBasic

Shrinks an image by the factor of two along each axis.

Applications

Usually used to speed-up image analysis at the cost of reduced precision. It is internally used to implement the pyramid strategy in template matching filters.

Name	Type	Range	Description
inImage	Image		Input image
inScaleStep	Integer	0 - 12	Defines how many times the image size is divided by 2
inFunction	DownsampleFunction
outImage	Image		Output image

Description

The operation shrinks the inImage reducing its dimensions by a factor of two inScaleStep times.

Remarks

The operation produces a new image by averaging four neighboring pixels from the source image repeatedly. New width and height of image are always rounded up, thus pixels from source image at last row or column are averaged in pairs or copied when corresponding dimension is odd.

This operation can be used as faster replacement for ShrinkImageNTimes.

Hardware Acceleration

This operation is optimized for SSE2 technology for pixels of types: UINT8, SINT8, UINT16, SINT16, SINT32, REAL.

This operation is optimized for AVX2 technology for pixels of types: UINT8, SINT8, UINT16, SINT16, SINT32, REAL.

This operation is optimized for NEON technology for pixels of types: UINT8, SINT8, UINT16, SINT16, SINT32, REAL.

This operation supports automatic parallelization for multicore and multiprocessor systems.

Complexity Level