.TH "MPSImageGaussianPyramid" 3 "Mon Jul 9 2018" "Version MetalPerformanceShaders-119.3" "MetalPerformanceShaders.framework" \" -*- nroff -*-
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.SH NAME
MPSImageGaussianPyramid
.SH SYNOPSIS
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\fC#import <MPSImageConvolution\&.h>\fP
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Inherits \fBMPSImagePyramid\fP\&.
.SS "Additional Inherited Members"
.SH "Detailed Description"
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The Gaussian image pyramid is constructed as follows: First the zeroth level mipmap of the input image is filtered with the specified convolution kernel\&. The default the convolution filter kernel is 
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k = w w^T, where w = [ 1/16,  1/4,  3/8,  1/4,  1/16 ]^T,

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 but the user may also tweak this kernel with a \fBcenterWeight\fP parameter: 'a': 
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k = w w^T, where w = [ (1/4 - a/2),  1/4,  a,  1/4,  (1/4 - a/2) ]^T

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 or the user can provide a completely custom kernel\&. After this the image is downsampled by removing all odd rows and columns, which defines the next level in the Gaussian image pyramid\&. This procedure is continued until every mipmap level present in the image texture are filled with the pyramid levels\&.
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In case of the Gaussian pyramid the user must run the operation in-place using: \fBinPlaceTexture:fallbackCopyAllocator:\fP, where the fallback allocator is ignored\&. 

.SH "Author"
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Generated automatically by Doxygen for MetalPerformanceShaders\&.framework from the source code\&.