The OpenVX Specification  a73e458
Mean and Standard Deviation

## Detailed Description

Computes the mean pixel value and the standard deviation of the pixels in the input image (which has a dimension width and height).

The mean value is computed as [R00081]:

$\mu = \frac{\left(\sum_{y=0}^h \sum_{x=0}^w src(x,y) \right)} {(width * height)}$

The standard deviation is computed as [R00082]:

$\sigma = \sqrt{\frac{\left(\sum_{y=0}^h \sum_{x=0}^w (\mu - src(x,y))^2 \right)} {(width * height)}}$

## Functions

vx_node VX_API_CALL vxMeanStdDevNode (vx_graph graph, vx_image input, vx_scalar mean, vx_scalar stddev)
[Graph] Creates a mean value and standard deviation node. More...

## ◆ vxMeanStdDevNode()

 vx_node VX_API_CALL vxMeanStdDevNode ( vx_graph graph, vx_image input, vx_scalar mean, vx_scalar stddev )

[Graph] Creates a mean value and standard deviation node.

Parameters
 [in] graph The reference to the graph [R00207]. [in] input The input image. VX_DF_IMAGE_U8 is supported [R00208]. [out] mean The VX_TYPE_FLOAT32 average pixel value [R00209]. [out] stddev The VX_TYPE_FLOAT32 standard deviation of the pixel values [R00210].
Returns
vx_node [R00211].
Return values
 vx_node A node reference. Any possible errors preventing a successful creation should be checked using vxGetStatus