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RLEGenerator.h Go to the documentation of this file. //-*-c++-*- #ifndef INCLUDED_RLEGenerator_h_ #define INCLUDED_RLEGenerator_h_ #include "Vision/FilterBankGenerator.h" #include "Vision/cmvision.h" #include <ext/hash_map> #include <vector> //! Generates RLE compressed FilterBankEvents (generally from indexed color images from, say, SegmentedColorGenerator) /*! Uses the CMVision library for main processing. * * getImage() will return the first run, from the upper left hand * corner. The type is RLEGenerator::run. * * The RLE produced isn't quite optimal in terms of size. To make it * easier to directly process the RLE for recognition tasks, each run * will be broken at the end of the row. So a solid image will still * contain <var>height</var> runs instead of just one. * * Also, the run structures contain extra fields to be used for * region connecting. These fields aren't sent over wireless, and * are filled in by the RegionGenerator. I don't necessarily like * the tight coupling between the RLE and Region Generators that this * requires, but it saves a copy of the data and allows us to use * CMVision instead of rewriting. * * Note that since the amount of data for each row is variable * (depends on the complexity of that row) the row stride and skip * are useless. You'll have to process the RLE yourself to find a * given index. * * If the incoming events is a SegmentedColorFilterBankEvents, then * it will post a SegmentedColorFilterBank to retain additional color * information. If the event is of a different format, it will post * a regular FilterBankEvent. * * Note that although you could hook this class up to a raw intensity * image, it is primarily of use with segmented color images because * it doesn't handle gradients or noise well at all - this type of * encoding/compression assumes cartoonish images of large blocks of * flat color. However, if you have some kind of other preprocessing * that also provides suitable data, this can encode it for you. * * The format used for serialization is: (code is in SaveBuffer()) * - <@c FilterBankGenerator: superclass header> <i>(First saves the superclass's info)</i> * - <@c string: "RLEImage"> <i>(remember a 'string' is len+str+0; so this is the literal "\010\0\0\0RLEImage\0"; also remember "\010" is octal for 8)</i> * - <@c unsigned @c int: num_runs> <i>(how many runs will follow)</i> * - for each of num_runs: * - <@c char: color> <i>(index value of color of run)</i> * - <@c short: x> <i>(x position of start of run ("unknown" runs are skipped - assume index 0 for pixels which are jumped))</i> * - <@c short: width> <i>(length of run, will not exceed remaining width of image)</i> * * Note that the RLEGenerator doesn't save the color infomation * regarding what each index value "means". This is just a * compression stage, pure and simple. You'll need to look at the * RLEGenerator's source (@e probably SegmentedColorGenerator, but * doesn't @e have to be) to determine how to interpret the indicies. * * @see SegCamBehavior for information on transmission over wireless. * * @see FilterBankGenerator more information on serialization */ class RLEGenerator : public FilterBankGenerator { public: typedef uchar cmap_t; //!< the type to use for a color index typedef CMVision::run<cmap_t> run; //!< use the CMVision library's run structure //! constructor RLEGenerator(EventBase::EventGeneratorID_t gid, unsigned int sid, unsigned int mysid); //! destructor virtual ~RLEGenerator(); static std::string getClassDescription() { return "Compresses a FilterBankGenerator's channels using run length encoding"; } //! should receive FilterBankEvents from any standard format FilterBankGenerator (like RawCameraGenerator) virtual void processEvent(const EventBase& event); virtual unsigned int getBinSize() const; virtual unsigned int LoadBuffer(const char buf[], unsigned int len); virtual unsigned int SaveBuffer(char buf[], unsigned int len) const; //! returns the number of runs for the image virtual unsigned int getNumRuns(unsigned int layer, unsigned int chan) const { if(!imageValids[layer][chan]) getImage(layer,chan); return numRuns[layer][chan]; } //! returns the actual runs of the specified image virtual const run * getRuns(unsigned int layer, unsigned int chan) const { return reinterpret_cast<const run*>(getImage(layer,chan)); } //! returns a specific run of the specified image virtual const run& getRun(unsigned int layer, unsigned int chan, unsigned int i) const { return reinterpret_cast<const run*>(getImage(layer,chan))[i]; } //! returns the generator this is receiving its events from (or the last one anyway) virtual FilterBankGenerator * getSourceGenerator() const { return src; } protected: static const unsigned int MIN_EXP_RUN_LENGTH=8; //!< The expected minimum average length of each run static const unsigned int XMIT_BYTES_PER_RUN=sizeof(cmap_t)+sizeof(short)+sizeof(short); //!< number of bytes needed to send each run virtual void setDimensions(); //!< sets the width, height, skip and stride, as well as #maxRuns virtual void setNumImages(unsigned int nLayers, unsigned int nChannels); virtual unsigned char * createImageCache(unsigned int layer, unsigned int chan) const; virtual void calcImage(unsigned int layer, unsigned int chan) const; virtual void destruct(); //! uses a heuristic to predict the maximum number of runs expected per layer unsigned int calcExpMaxRuns(unsigned int layer) const { return getWidth(layer)*getHeight(layer)/MIN_EXP_RUN_LENGTH; } FilterBankGenerator * src; //!< the generator of the last FilterBankEvent received unsigned int ** numRuns; //!< a matrix of ints, holds the number of used runs for each image unsigned int * maxRuns; //!< the maximum number of runs possible for each layer private: RLEGenerator(const RLEGenerator& fbk); //!< don't call const RLEGenerator& operator=(const RLEGenerator& fbk); //!< don't call }; /*! @file * @brief Describes RLEGenerator, which generates RLE compressed FilterBankEvents (generally from indexed color images from, say, SegmentedColorGenerator) * @author alokl (Creator) * @author ejt (reorganized) * * $Author: ejt $ * $Name: tekkotsu-2_0_1+Doc $ * $Revision: 1.6 $ * $State: Exp $ * $Date: 2004/02/05 23:33:48 $ */ #endif

Tekkotsu v2.0.1+Doc

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