Point Cloud Library (PCL)  1.7.0
/tmp/buildd/pcl-1.7-1.7.0/filters/include/pcl/filters/median_filter.h
00001 /*
00002  * Software License Agreement (BSD License)
00003  *
00004  * Point Cloud Library (PCL) - www.pointclouds.org
00005  * Copyright (c) 2012-, Open Perception, Inc.
00006 
00007  * All rights reserved.
00008 
00009  * Redistribution and use in source and binary forms, with or without
00010  * modification, are permitted provided that the following conditions
00011  * are met:
00012  *
00013  *  * Redistributions of source code must retain the above copyright
00014  *    notice, this list of conditions and the following disclaimer.
00015  *  * Redistributions in binary form must reproduce the above
00016  *    copyright notice, this list of conditions and the following
00017  *    disclaimer in the documentation and/or other materials provided
00018  *    with the distribution.
00019  * * Neither the name of the copyright holder(s) nor the names of its
00020  *    contributors may be used to endorse or promote products derived
00021  *    from this software without specific prior written permission.
00022  *
00023  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00024  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00025  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
00026  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
00027  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00028  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00029  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00030  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
00031  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
00032  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
00033  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00034  * POSSIBILITY OF SUCH DAMAGE.
00035  *
00036  * $Id$
00037  *
00038  */
00039 
00040 
00041 #ifndef PCL_FILTERS_MEDIAN_FILTER_H_
00042 #define PCL_FILTERS_MEDIAN_FILTER_H_
00043 
00044 #include <pcl/filters/filter.h>
00045 
00046 namespace pcl
00047 {
00048   /** \brief Implementation of the median filter.
00049     * The median filter is one of the simplest and wide-spread image processing filters. It is known to perform well
00050     * with "shot"/impulse noise (some individual pixels having extreme values), it does not reduce contrast across steps
00051     * in the function (as compared to filters based on averaging), and it is robust to outliers. Furthermore, it is
00052     * simple to implement and efficient, as it requires a single pass over the image. It consists of a moving window of
00053     * fixed size that replaces the pixel in the center with the median inside the window.
00054     *
00055     * \note This algorithm filters only the depth (z-component) of _organized_ and untransformed (i.e., in camera coordinates)
00056     * point clouds. An error will be outputted if an unorganized cloud is given to the class instance.
00057     *
00058     * \author Alexandru E. Ichim
00059     * \ingroup filters
00060     */
00061   template <typename PointT>
00062   class MedianFilter : public pcl::Filter<PointT>
00063   {
00064       using pcl::Filter<PointT>::input_;
00065       typedef typename pcl::Filter<PointT>::PointCloud PointCloud;
00066 
00067     public:
00068       /** \brief Empty constructor. */
00069       MedianFilter ()
00070         : window_size_ (5)
00071         , max_allowed_movement_ (std::numeric_limits<float>::max ())
00072       { }
00073 
00074       /** \brief Set the window size of the filter.
00075         * \param[in] window_size the new window size
00076         */
00077       inline void
00078       setWindowSize (int window_size)
00079       { window_size_ = window_size; }
00080 
00081       /** \brief Get the window size of the filter.
00082         * \returns the window size of the filter
00083         */
00084       inline int
00085       getWindowSize () const
00086       { return window_size_; }
00087 
00088       /** \brief Set the largest value one dexel is allowed to move
00089         * \param[in] max_allowed_movement maximum value a dexel is allowed to move during filtering
00090         */
00091       inline void
00092       setMaxAllowedMovement (float max_allowed_movement)
00093       { max_allowed_movement_ = max_allowed_movement; }
00094 
00095       /** \brief Get the maximum distance one point is allowed to move along the z-axis.
00096         * \returns the maximum distance a dexel is allowed to move
00097         */
00098       inline float
00099       getMaxAllowedMovement () const
00100       { return max_allowed_movement_; }
00101 
00102       /** \brief Filter the input data and store the results into output.
00103         * \param[out] output the result point cloud
00104         */
00105       void
00106       applyFilter (PointCloud &output);
00107 
00108     protected:
00109       int window_size_;
00110       float max_allowed_movement_;
00111   };
00112 }
00113 
00114 #ifdef PCL_NO_PRECOMPILE
00115 #include <pcl/filters/impl/median_filter.hpp>
00116 #else
00117 #define PCL_INSTANTIATE_MedianFilter(T) template class PCL_EXPORTS pcl::MedianFilter<T>;
00118 #endif
00119 #endif /* PCL_FILTERS_MEDIAN_FILTER_H_ */