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<<TableOfContents(3)>>

== Users ==
=== Extract Indices ===
The `ExtractIndices` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_extract_indices.html|pcl::ExtractIndices]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/extract_indices.html#extract-indices|tutorial]]).

The following [[dynamic_reconfigure]] parameters are used:
{{{
#!clearsilver CS/NodeAPI
# Autogenerated param section. Do not hand edit.
param {
group.0 {
name=Dynamically Reconfigurable Parameters
desc=See the [[dynamic_reconfigure]] package for details on dynamically reconfigurable parameters.
0.name= ~negative
0.default= False
0.type= bool
0.desc=Extract indices or the negative (all-indices)
}
}
# End of autogenerated section. You may edit below.
}}}

=== PassThrough ===
The `PassThrough` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_pass_through.html|pcl::PassThrough]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/passthrough.html|PassThrough tutorial]]).

The following [[dynamic_reconfigure]] parameters are used:
{{{
#!clearsilver CS/NodeAPI
# Autogenerated param section. Do not hand edit.
param {
group.0 {
name=Dynamically Reconfigurable Parameters
desc=See the [[dynamic_reconfigure]] package for details on dynamically reconfigurable parameters.
0.name= ~filter_field_name
0.default= z
0.type= str
0.desc=The field name used for filtering
1.name= ~filter_limit_min
1.default= 0.0
1.type= double
1.desc=The minimum allowed field value a point will be considered from Range: -1000.0 to 1000.0
2.name= ~filter_limit_max
2.default= 1.0
2.type= double
2.desc=The maximum allowed field value a point will be considered from Range: -1000.0 to 1000.0
3.name= ~filter_limit_negative
3.default= False
3.type= bool
3.desc=Set to true if we want to return the data outside [filter_limit_min; filter_limit_max].
4.name= ~input_frame
4.default=
4.type= str
4.desc=The input TF frame the data should be transformed into before processing, if input.header.frame_id is different.
5.name= ~output_frame
5.default=
5.type= str
5.desc=The output TF frame the data should be transformed into after processing, if input.header.frame_id is different.
}
}
# End of autogenerated section. You may edit below.
}}}

=== ProjectInliers ===
The `ProjectInliers` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_project_inliers.html|pcl::ProjectInliers]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/project_inliers.html|Projection tutorial]]).

=== RadiusOutlierRemoval ===
The `RadiusOutlierRemoval` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_radius_outlier_removal.html|pcl::RadiusOutlierRemoval]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/remove_outliers.html|Outlier removal tutorial]]).


=== StatisticalOutlierRemoval ===
The `StatisticalOutlierRemoval` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_statistical_outlier_removal.html|pcl::StatisticalOutlierRemoval]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/statistical_outlier.html|Statistical outlier removal tutorial]]).

The following [[dynamic_reconfigure]] parameters are used:
{{{
#!clearsilver CS/NodeAPI
# Autogenerated param section. Do not hand edit.
param {
group.0 {
name=Dynamically Reconfigurable Parameters
desc=See the [[dynamic_reconfigure]] package for details on dynamically reconfigurable parameters.
0.name= ~mean_k
0.default= 2
0.type= int
0.desc=The number of points (k) to use for mean distance estimation Range: 2 to 100
1.name= ~stddev
1.default= 0.0
1.type= double
1.desc=The standard deviation multiplier threshold. All points outside the mean +- sigma * std_mul will be considered outliers. Range: 0.0 to 5.0
2.name= ~negative
2.default= False
2.type= bool
2.desc=Set whether the inliers should be returned (true) or the outliers (false)
}
}
# End of autogenerated section. You may edit below.
}}}

=== VoxelGrid ===
The `VoxelGrid` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_voxel_grid.html|pcl::VoxelGrid]] filter (also see [[https://pcl.readthedocs.io/projects/tutorials/en/latest/voxel_grid.html|Downsampling tutorial]]).

The following [[dynamic_reconfigure]] parameters are used:
{{{
#!clearsilver CS/NodeAPI
# Autogenerated param section. Do not hand edit.
param {
group.0 {
name=Dynamically Reconfigurable Parameters
desc=See the [[dynamic_reconfigure]] package for details on dynamically reconfigurable parameters.
0.name= ~leaf_size
0.default= 0.01
0.type= double
0.desc=The size of a leaf (on x,y,z) used for downsampling. Range: 0.0 to 1.0
1.name= ~filter_field_name
1.default= z
1.type= str
1.desc=The field name used for filtering
2.name= ~filter_limit_min
2.default= 0.0
2.type= double
2.desc=The minimum allowed field value a point will be considered from Range: -1000.0 to 1000.0
3.name= ~filter_limit_max
3.default= 1.0
3.type= double
3.desc=The maximum allowed field value a point will be considered from Range: -1000.0 to 1000.0
4.name= ~filter_limit_negative
4.default= False
4.type= bool
4.desc=Set to true if we want to return the data outside [filter_limit_min; filter_limit_max].
5.name= ~input_frame
5.default=
5.type= str
5.desc=The input TF frame the data should be transformed into before processing, if input.header.frame_id is different.
6.name= ~output_frame
6.default=
6.type= str
6.desc=The output TF frame the data should be transformed into after processing, if input.header.frame_id is different.
}
}
# End of autogenerated section. You may edit below.
}}}


=== CropBox ===
The `CropBox` nodelet wraps the [[https://pointclouds.org/documentation/classpcl_1_1_crop_box.html|pcl::CropBox]] filter.

The following [[dynamic_reconfigure]] parameters are used:
{{{
#!clearsilver CS/NodeAPI
# Autogenerated param section. Do not hand edit.
param {
group.0 {
name=Dynamically Reconfigurable Parameters
0.name= ~min_x
0.default= -1.0
0.type= double
0.desc=The minimum allowed x value a point will be considered from. Range: -1000.0 to 1000.0
1.name= ~max_x
1.default= 1.0
1.type= double
1.desc=The maximum allowed x value a point will be considered from. Range: -1000.0 to 1000.0
2.name= ~min_y
2.default= -1.0
2.type= double
2.desc=The minimum allowed y value a point will be considered from. Range: -1000.0 to 1000.0
3.name= ~max_y
3.default= 1.0
3.type= double
3.desc=The maximum allowed y value a point will be considered from. Range: -1000.0 to 1000.0
4.name= ~min_z
4.default= -1.0
4.type= double
4.desc=The minimum allowed z value a point will be considered from. Range: -1000.0 to 1000.0
5.name= ~max_z
5.default= 1.0
5.type= double
5.desc=The maximum allowed z value a point will be considered from. Range: -1000.0 to 1000.0
6.name= ~keep_organized
6.default= False
6.type= bool
6.desc=If true, the pointcloud shape (width, height) will be retained and filtered-out points will be set to nan. If false, pointcloud is reshaped to height 1 and filtered-out points are removed. Please not this is broken in Melodic and the pointcloud is always unorganized. In Noetic, it works correctly.
7.name= ~negative
7.default= False
7.type= bool
7.desc=Set to true if we want to return the data outside the limiting box. If false, data inside the box are returned.
8.name= ~input_frame
8.default=
8.type= str
8.desc=The input TF frame the data should be transformed into before processing, if input.header.frame_id is different.
9.name= ~output_frame
9.default=
9.type= str
9.desc=The output TF frame the data should be transformed into after processing, if input.header.frame_id is different.
}
}
# End of autogenerated section. You may edit below.
}}}


== Developers ==

All [[pcl_ros]] nodelet filters inherit from `pcl_ros::Filter`, which requires that any class inheriting from it implement the following interface:

 * `child_init()`, `filter()`, `onInit()` and `config_callback()` are all virtual and can be overridden

 * `filter (PointCloud2 &output)` is pure abstract and must be implemented

 * if `child_init (ros::NodeHandle &nh, bool &has_service)` is implemented, and `has_service` is set to '''true''', the `Filter` base class `dynamic_reconfigure` service will not be created


=== Common ROS parameters ===

The following ROS parameters are usually read on startup for any [[pcl_ros]] nodelet.

 * '''max_queue_size''', ''int'' : defines the maximum queue size the ROS subscribers and publishers in the nodelet should use (see [[http://www.ros.org/doc/api/roscpp/html/classros_1_1NodeHandle.html#a0b8398fd50b8f7b3cc44f642252e4fea|ros::NodeHandle::subscribe]] for more information).

 * '''use_indices''', ''bool'' : usually indicates whether the nodelet should listen for incoming data on '''~indices'''. This data represents a subset of point indices (`pcl::PointIndices` message) that should be used from the input dataset.

 * '''approximate_sync''', ''bool'' : indicates whether the input topics that the nodelet listens to, should synchronize with an `ApproximateTimeSynchronizer` (their `header.stamp` can differ) or an `ExactTimeSynchronizer` (their `header.stamp` must be identical)

=== Input/Output topics ===

The following list of ROS topics are used by all [[pcl_ros]] filters:

 * '''input''',  in, [[sensor_msgs/PointCloud2]] : input point cloud data to filter.
 * '''indices''', in, [[pcl/PointIndices]] : input point cloud data indices to use from '''input'''.

 * '''output''', out, [[sensor_msgs/PointCloud2]] : the resultant filtered point cloud data.