# findNearestNeighbors

Find nearest neighbors of a point in point cloud

## Syntax

## Description

`[`

returns the `indices`

,`dists`

] = findNearestNeighbors(`ptCloud`

,`point`

,`K`

)`indices`

for the K-nearest neighbors of a query point in the
input point cloud. `ptCloud`

can be an unorganized or organized point
cloud. The K-nearest neighbors of the query point are computed by using the Kd-tree based
search algorithm.

`[`

returns the K-nearest neighbors of a query point in the input point cloud. The input point
cloud is an organized point cloud generated by a depth camera. The K-nearest neighbors of
the query point are determined using fast approximate K-nearest neighbor search algorithm. `indices`

,`dists`

] = findNearestNeighbors(`ptCloud`

,`point`

,`K`

,`camMatrix`

)

The function uses the camera projection matrix `camMatrix`

to know
the relationship between adjacent points and hence, speeds up the nearest neighbor search.
However, the results have lower accuracy as compared to the Kd-tree based approach.

**Note**

This syntax only supports organized point cloud data produced by RGB-D sensors.

You can use

`estimateCameraMatrix`

to estimate camera projection matrix for the given point cloud data.

`[`

specifies options using one or more name-value arguments in addition to the input arguments
in the preceding syntaxes.`indices`

,`dists`

] = findNearestNeighbors(___,`Name,Value`

)

## Examples

## Input Arguments

## Output Arguments

## References

[1] Muja, M. and David G. Lowe. "Fast
Approximate Nearest Neighbors with Automatic Algorithm Configuration". *In VISAPP
International Conference on Computer Vision Theory and Applications*. 2009. pp.
331–340.

## Extended Capabilities

## Version History

**Introduced in R2015a**