Subversion Repositories svnkaklik

Rev

Blame | Last modification | View Log | Download

/*
    Copyright (C) 2004    John Orlando
    
   AVRcam: a small real-time image processing engine.

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.

    You should have received a copy of the GNU General Public
    License along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

   For more information on the AVRcam, please contact:

   john@jrobot.net

   or go to www.jrobot.net for more details regarding the system.
*/
/*********************************************************
        Module Name: FrameMgr.c
        Module Date: 04/10/2004
        Module Auth: John Orlando
        
        Description: This modules is responsible for performing
        both medium and high level processing on image data.
        This is performed at both the line level as well as
        the frame level.  It controls the main flow of the
        system, adhering to all the critical timing 
        requirements (such as when serial data can be transferred,
        etc).
    
    Revision History:
    Date        Rel Ver.    Notes
    4/10/2004      0.1     Module created
    6/30/2004      1.0     Initial release for Circuit Cellar
                           contest.
    11/15/2004     1.2     Updated processLine() function so 
                           it will remove objects less than
                           a specified length/width (reduces
                           shot noise)
*********************************************************/

/*      Includes */
#include <stdlib.h>
#include <string.h>
#include <avr/io.h>
#include "Executive.h"
#include "UIMgr.h"
#include "FrameMgr.h"
#include "CamInterface.h"
#include "UartInterface.h"
#include "Utility.h"
#include "I2CInterface.h"
#include "CamConfig.h"
#include "CommonDefs.h"

/*      Local Structures and Typedefs */
enum
{
        ST_FrameMgr_idle,
        ST_FrameMgr_TrackingFrame,
        ST_FrameMgr_DumpingFrame
};

typedef unsigned char FrameMgr_State_t;

/*  Definitions */
/* The most objects that can be tracked at any one time is 8.  
This number is determined by the number of bytes that can be
sent out during a frame (one byte per line, 144 lines per frame) 
with the number of bytes in a tracked object (7) + some wiggle
room :-) ... I guess this could be increased to around 20 if
we had enough room and cycles to process objects between lines */
#define MAX_TRACKED_OBJECTS     8

/* This defines the number of bytes that make up a trackedObject_t
structure... */
#define SIZE_OF_TRACKED_OBJECT 8

/* This define is used to turn off the timer overflow interrupt
that is generated when the PCLK overflows TIMER1 */
#define DISABLE_PCLK_TIMER1_OVERFLOW_BITMASK 0xFB

/* This define is used to determine if a run length is too small
to be concerned with.  This helps to reduce the number of false
positives. */
#define MIN_OBJECT_TRACKING_WIDTH 3

/* This define is used to determine if an object has enough
height to be considered worth tracking...it is used to reduce
shot noise */
#define MIN_OBJECT_TRACKING_HEIGHT 3

/* This define is used to indicate how often the filter routine
that removes objects less than MIN_OBJECT_TRACKING_HEIGHT should
be executed.  It is measured in a number of lines (7 nominally). */
#define RUN_OBJECT_FILTER_MASK 0x07

/* This enum describes the possible colors that can
be tracked by the system.  This can't be represented as
simple color names (red, brown, etc) due to the fact that
the user sets which colors will be associated with which
bits.  Remember...after the AND operation of the indexed
color map values executes, either a single bit indicating
the color should be set, or no bits indicating that the
color isn't represented in the color map (notTracked). */
enum
{
        notTracked,
        color1,         /* bit 1 color */
        color2,         /* bit 2 color */
        color3,         /* bit 3 color */
        color4,         /* bit 4 color */
        color5,         /* bit 5 color */
        color6,         /* bit 6 color */
        color7,         /* bit 7 color */
        color8          /* bit 8 color */
};

typedef unsigned char trackedColor_t;

/* This structure defines the info that needs to be
maintained for each trackedObject in the trackingTable */
typedef struct
{
        trackedColor_t  color;
        unsigned char lastLineXStart;
        unsigned char lastLineXFinish;
        unsigned char x_upperLeft;
        unsigned char y_upperLeft;
        unsigned char x_lowerRight;
        unsigned char y_lowerRight;
        unsigned char objectValid;  /* used to be a fill byte...now it is
                                     used to determine if the object is valid
                                     or not...it gets invalidated if it is
                                     determined that it is too small, or
                                     that the object is within another object */
} trackedObject_t;

/* These defines are used to index into each individual element in the
trackedObject_t structure.  This seems to be MUCH more efficient than
accessing the elements in GCC. */
#define COLOR_OFFSET                0
#define LAST_LINE_X_START_OFFSET    1
#define LAST_LINE_X_FINISH_OFFSET   2
#define X_UPPER_LEFT_OFFSET         3
#define Y_UPPER_LEFT_OFFSET         4
#define X_LOWER_RIGHT_OFFSET        5
#define Y_LOWER_RIGHT_OFFSET        6
#define VALID_OBJECT_OFFSET         7

/*  Local Variables */
/* The trackedObjectTable is used to hold up to eight tracked objects
while they are being acquired. */
static trackedObject_t trackedObjectTable[MAX_TRACKED_OBJECTS];
static trackedObject_t *pCurrentTrackedObjectTable = trackedObjectTable;
static unsigned char lineCount = 0;
static FrameMgr_State_t currentState = ST_FrameMgr_idle;
static unsigned char numCurrTrackedObjects = 0;
static unsigned char numPrevTrackedObjects = 0;
static unsigned char trackedLineCount = 0;

/*  Local Functions  */
static void FrameMgr_findConnectedness(void);

/*  Extern Functions */
/* These functions are located in assembly files, and thus
must be externed here so they can be referenced in the source below. */
extern void CamIntAsm_waitForNewTrackingFrame(unsigned char *pBuffer, unsigned char *pMemLookup);
extern void CamIntAsm_waitForNewDumpFrame(unsigned char *pCurrBuffer, unsigned char *pPrevBuffer);
extern void CamIntAsm_acquireTrackingLine(unsigned char *pBuffer, unsigned char *pMemLookup);
extern void CamIntAsm_acquireDumpLine(unsigned char *pCurrBuffer, unsigned char *pPrevBuffer);

/***********************************************************
        Function Name: FrameMgr_init
        Function Description: This function is responsible
        for initializing the FrameMgr.  This includes 
        setting up the various buffers and data needed to 
        process each frame of image data.
        Inputs:  none
        Outputs: none
***********************************************************/    
void FrameMgr_init(void)
{
        memset(trackedObjectTable,0x00,sizeof(trackedObjectTable));
}


/***********************************************************
        Function Name: FrameMgr_dispatchEvent
        Function Description: This function is responsible for
        taking an incoming event and performing the needed
        actions with it as pertains to the FrameMgr.
        Inputs:  event - the generated event
        Outputs: none
***********************************************************/    
void FrameMgr_dispatchEvent(unsigned char event)
{       
        switch(event)
        {
                case EV_DUMP_FRAME:
            /* try re-initializing the camera before we start dumping */
            
                        CamConfig_setCamReg(0x11,0x01);  /* reduce the frame rate for dumping*/
                        CamConfig_sendFifoCmds();
                        Utility_delay(1000);            /* allow the new frame rate to settle */
                        lineCount = 0;
                        currentState = ST_FrameMgr_DumpingFrame;
                        //CamIntAsm_waitForNewDumpFrame(currentLineBuffer,previousLineBuffer);
            FrameMgr_acquireLine();
                        break;
                
                case EV_ENABLE_TRACKING:
                        currentState = ST_FrameMgr_TrackingFrame;                                       
                        FrameMgr_acquireFrame();
                        break;
                        
                case EV_ACQUIRE_FRAME_COMPLETE:
                        FrameMgr_processFrame();
                        break;
                
                case EV_PROCESS_FRAME_COMPLETE:
                        FrameMgr_acquireFrame();
                        break;

                case EV_SERIAL_DATA_RECEIVED:
                        if (currentState != ST_FrameMgr_idle)
                        {
                                /* we need to go back to processing line data, since
                                serial data reception interrupted us....just trash the
                                frame and act like the frame has been processed, which
                                will kick off the system to wait for the next line */
                                PUBLISH_EVENT(EV_PROCESS_FRAME_COMPLETE);
                        }
                        break;
                        
                case EV_DISABLE_TRACKING:
                        /* tracking needs to be turned off */
                        currentState = ST_FrameMgr_idle;
                        break;
        }
}

/***********************************************************
        Function Name: FrameMgr_acquireFrame
        Function Description: This function is responsible for
        beginning of the acquisition of a new frame of data
        from the camera interface. The acquisition of this line 
        depends on the current state of the FrameMgr.
        Inputs:  none
        Outputs: none
***********************************************************/    
void FrameMgr_acquireFrame(void)
{
        if (currentState == ST_FrameMgr_TrackingFrame)
        {
                trackedLineCount = 0;
                numPrevTrackedObjects = numCurrTrackedObjects;
                numCurrTrackedObjects = 0;
                
                /* clear out the tracking table, and wait for the new frame
                to start */
                memset(trackedObjectTable,0x00,sizeof(trackedObjectTable));
                //CamIntAsm_waitForNewTrackingFrame(currentLineBuffer,colorMap);
        WAIT_FOR_VSYNC_HIGH();
        CamIntAsm_acquireTrackingLine(currentLineBuffer,colorMap);
        }
}

/***********************************************************
        Function Name: FrameMgr_acquireLine
        Function Description: This function is responsible for
        acquiring a line of data from the camera interface.
        The acquisition of this line depends on the current
        state of the FrameMgr.
        Inputs:  none
        Outputs: none
***********************************************************/    
void FrameMgr_acquireLine(void)
{
        unsigned char tmpLineCount;
        
        /* clearing out the buffers takes too long...we should
        just overwrite the data here without a problem when
        we start acquiring...at no point do we check for 
        a 0x00 value in the current or previous lineBuffers,
        so it was a bit excessive :-)  */
        
        /* check which state we are in and proceed as needed */
        if (currentState == ST_FrameMgr_DumpingFrame)
        {
                tmpLineCount = lineCount*2;
        
        /* clearing out the line data in dump mode is ok, and actually
        is needed, since it is possible for the first dump line in
        a frame to come back with the last line captured of the
        last capture session...*/
        memset(currentLineBuffer,0x00,LENGTH_OF_LINE_BUFFER);
        memset(previousLineBuffer,0x00,LENGTH_OF_LINE_BUFFER);
                /* wait for another VSYNC so we know which frame to use 
                to start looking for a line to receive */
                WAIT_FOR_VSYNC_HIGH();  
                WAIT_FOR_VSYNC_LOW();
                
                /* look at lineCount to determine how many HREFs we should
                wait before we start sampling */
                while(tmpLineCount != 0)
                {
                        WAIT_FOR_HREF_HIGH(); 
                        tmpLineCount--;
                        WAIT_FOR_HREF_LOW(); 
                }
                
                /*  we should now be ready to sample our line...*/
                CamIntAsm_acquireDumpLine(currentLineBuffer,previousLineBuffer);
        }               
        else if (currentState == ST_FrameMgr_TrackingFrame)
        {
                WAIT_FOR_HREF_LOW();
                CamIntAsm_acquireTrackingLine(currentLineBuffer,colorMap);
        }
}

/***********************************************************
        Function Name: FrameMgr_processLine
        Function Description: This function is responsible for
        parsing the received image line and performing either
        connected region mapping (if in the Tracking state) or
        sending out the raw sampled data (if in the Dumping
        state).
        Inputs:  none
        Outputs: none
***********************************************************/    
void FrameMgr_processLine(void)
{
        unsigned char i;
        volatile unsigned char dataToSend;
        unsigned char *pTrackedObjectData = (unsigned char *)pCurrentTrackedObjectTable;
#ifdef DEBUG_TRACKED_LINE    
        unsigned char *pSendData;
    unsigned char asciiBuffer[5];
    unsigned char pixelCount = 0;
#endif    
        
        if (currentState == ST_FrameMgr_DumpingFrame)
        {
                /* we want to sit in a tight loop and send the acquired data
                sitting in current and previous line buffers out the serial
                port...it is sent out the serial port immediately instead
                of going into the UIMgr tx fifo because we can't do anything
                until its sent out anyway...may as well just get it out now     */
                
                /* currentLineBuffer is getting "g" previousLineBuffer is getting "b-r" */
                UartInt_txByte(0x0B);                   /* send the header byte */
                UartInt_txByte(lineCount);              /* send the line count */
                for (i=0; i<NUM_PIXELS_IN_A_DUMP_LINE; i+=2)
                {
                        /* when a dump line is sampled, the upper byte can potentially
                        have garbage in it...we don't have time to mask it off as we're
                        sampling, so it is done here before we send it out...we also
                        combine the samples together so we really are sending up a
                        sample for line N as well as line N+1 */
                        dataToSend = currentLineBuffer[i];
                        dataToSend &= 0x0F;
                        dataToSend <<= 4;
                        dataToSend |= (previousLineBuffer[i] & 0x0F);
                        
                        /* dataToSend should be packed now */
                        UartInt_txByte(dataToSend);
                        
                        /* flip the colors around since we are doing all G on Y and BR on UV */
                        dataToSend = previousLineBuffer[i+1];
                        dataToSend &= 0x0F;
                        dataToSend <<= 4;
                        dataToSend |= (currentLineBuffer[i+1] & 0x0F);
                        
                        /* dataToSend should be packed now */
                        UartInt_txByte(dataToSend);
                }
                UartInt_txByte(0x0F);  /* send line end */
                /* once all the data is sent, increment out line count by 2 since
                we really get 2 lines worth of pixels on each pass */
                /* Update...increment only by 1, but only send 72 double-lines */
                lineCount++;
                
                /* check to see if we have retrieved all of the needed lines */
                if (lineCount >= 72)  /* half 144, since we send two lines at a time */
                {
                        /* we're done, so send the dump complete?...nope, just change
                        states and we should be fine */
                        lineCount = 0;
                        currentState = ST_FrameMgr_idle;
                        
                        /* disable the PCLK counting overflow interrupt */
                        TIMSK &= DISABLE_PCLK_TIMER1_OVERFLOW_BITMASK;
                        
                        CamConfig_setCamReg(0x11,0x00);  /* reset the frame rate to normal*/
                        CamConfig_sendFifoCmds();
                }
                else
                {
                        /* we have more lines to acquire in this frame, so keep on truckin...*/
                        PUBLISH_FAST_EVENT(FEV_PROCESS_LINE_COMPLETE);
                }
        }
        else if (currentState == ST_FrameMgr_TrackingFrame)
        {
#ifdef DEBUG_TRACKED_LINE       
                /* send the received line over serial...this should only send
                until a pixelCount == 176 */
                pSendData = currentLineBuffer;
                itoa(trackedLineCount,asciiBuffer,10);
                UIMgr_txBuffer(asciiBuffer,3);
                UIMgr_txBuffer(" ",1);
                while(pixelCount < ACTUAL_NUM_PIXELS_IN_A_LINE)  
                {
                        memset(asciiBuffer,0x00,5);
                        itoa(*pSendData++,asciiBuffer,10);      /* color is first byte */
                        UIMgr_txBuffer(asciiBuffer,3); /* 3 ascii bytes for data */
                        UIMgr_txBuffer(" ",1);

                        pixelCount += *pSendData;       /* run-length is second byte */
                        memset(asciiBuffer,0x00,5);
                        itoa(*pSendData++,asciiBuffer,10);
                        UIMgr_txBuffer(asciiBuffer,3);
                        UIMgr_txBuffer(" ",1);
                }
                UIMgr_txBuffer("\n\r",2);

                trackedLineCount++;
                if (trackedLineCount == 144)
                {
                        UIMgr_txBuffer("  FC  \n\r",8);
                        trackedLineCount = 0;
                        PUBLISH_EVENT(EV_PROCESS_FRAME_COMPLETE);
                }
                else
                {
                        PUBLISH_EVENT(EV_PROCESS_LINE_COMPLETE);
                }       
#else
        /* determine if any of the RLE blocks overlap */
                FrameMgr_findConnectedness();
        
        /* we also want to remove any objects that are less than
        a minimum height...we already removed portions of the 
        run-length that are less than MIN_PIXEL_WIDTH in the
        findConnectedness() routine...doing it here instead of 
        a function to speed things up...this may end up slowing down the
        frame rate slightly, and can be removed if this isn't needed */
  
        /* run this routine once every 8 lines */       
        if ( (trackedLineCount & RUN_OBJECT_FILTER_MASK) == RUN_OBJECT_FILTER_MASK)
        {
            for (i=0; i<MAX_TRACKED_OBJECTS; i++)
            {
                if ( *(pTrackedObjectData + VALID_OBJECT_OFFSET) == TRUE)
                {
                    /* check to see if the object is already in
                    our past...i.e., its last */
                    if ( (*(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET) - 
                          *(pTrackedObjectData + Y_UPPER_LEFT_OFFSET)) < MIN_OBJECT_TRACKING_HEIGHT)
                    {
                        /* the object is less than the minimum height...see if it is adjacent
                        to the current line we just processed...if so, leave it here...otherwise,
                        it needs to be invalidated since its too small */
                        if ( trackedLineCount - *(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET) > 2)
                        {
                            /* invalidate the object */
                            *(pTrackedObjectData + VALID_OBJECT_OFFSET) = FALSE;
                            numCurrTrackedObjects--;
                        }
                    }
                }
                pTrackedObjectData += SIZE_OF_TRACKED_OBJECT;
            }
        }     
 
                trackedLineCount++;
                if (trackedLineCount == ACTUAL_NUM_LINES_IN_A_FRAME)
                {
                        /* an entire frame of tracking data has been acquired, so
                        publish an event letting the system know this fact */
                        PUBLISH_EVENT(EV_ACQUIRE_FRAME_COMPLETE);
                        /* disable the PCLK counting overflow interrupt */
                        TIMSK &= DISABLE_PCLK_TIMER1_OVERFLOW_BITMASK;
                        trackedLineCount = 0;
                }
                else
                {
                        PUBLISH_FAST_EVENT(FEV_PROCESS_LINE_COMPLETE);
                }
#endif          
        }
        else
        {
                /* ...and here? */
        }
}

/***********************************************************
        Function Name: FrameMgr_processFrame
        Function Description: This function is responsible for
        parsing the completed frame and performing all actions
        needed at this level.
        Inputs:  none
        Outputs: none
***********************************************************/    
void FrameMgr_processFrame(void)
{
        unsigned char i,k,color;
#if DEBUG_FRAME_DATA    
        unsigned char asciiBuffer[5];
    unsigned char j;
#endif    
        unsigned char *pTableData = (unsigned char *)pCurrentTrackedObjectTable;
        unsigned char tmpUpperLeftX,tmpUpperLeftY,tmpLowerRightX,tmpLowerRightY;
        
#if DEBUG_FRAME_DATA    
        /* we want to send all of the currently tracked table out
        the serial port for debugging */
        for (i=0; i<numCurrTrackedObjects; i++)
        {
                UIMgr_txBuffer("----------\r\n",12);
                for (j=0; j<SIZE_OF_TRACKED_OBJECT; j++)
                {
                        memset(asciiBuffer,0x00,5);
                        itoa(*pTableData++,asciiBuffer,10);
                        UIMgr_txBuffer(asciiBuffer,3); /* 3 ascii bytes for data
                                                                                                                + 1 space */
                        UIMgr_txBuffer("\r\n",2);
                }
        }
        
        /* finally, send a new line */
        UIMgr_txBuffer("\r\n",2);
        
        memset(asciiBuffer,0x00,5);
        itoa(numCurrTrackedObjects,asciiBuffer,10);
        UIMgr_txBuffer(asciiBuffer,3);
        UIMgr_txBuffer(" PFC\r\n",5);

#else   
        /* we only send tracking packets if there are tracked objects */                
    
        if (numCurrTrackedObjects > 0)
        {               
                UIMgr_writeTxFifo(0x0A);                                        /* header byte for a tracking packet */
        /* reset the pointer */
        pTableData = (unsigned char *)pCurrentTrackedObjectTable;
        
                UIMgr_writeTxFifo(numCurrTrackedObjects);       /* num of objects tracked */
                for (i=0; i<MAX_TRACKED_OBJECTS; i++)
                {
            /* we only want to process objects that have their objectValid flag
            set to TRUE */
            if ( *(pTableData + VALID_OBJECT_OFFSET) == TRUE)
            {
                /* the object is valid...convert the color from bit position to value...remember, 
                each bit in the "color" byte corresponds to a color */
                k=0;
                color = *(pTableData + COLOR_OFFSET);
                if (color == 128) k=0;
                else if (color == 64) k=1;
                else if (color == 32) k=2;
                else if (color == 16) k=3;
                else if (color == 8)  k=4;
                else if (color == 4)  k=5;
                else if (color == 2)  k=6;
                else if (color == 1)  k=7;
                
                tmpUpperLeftX = *(pTableData + X_UPPER_LEFT_OFFSET);        /* get the upper left X */
                tmpUpperLeftY = *(pTableData + Y_UPPER_LEFT_OFFSET);            /* get the upper left Y */              
                tmpLowerRightX = *(pTableData + X_LOWER_RIGHT_OFFSET);          /* get the lower right X */
                tmpLowerRightY = *(pTableData + Y_LOWER_RIGHT_OFFSET);          /* get the lower right Y */                     
                
                UIMgr_writeTxFifo(k);                                   /* send the color first */
                UIMgr_writeTxFifo(tmpUpperLeftX);
                UIMgr_writeTxFifo(tmpUpperLeftY);
                UIMgr_writeTxFifo(tmpLowerRightX);
                UIMgr_writeTxFifo(tmpLowerRightY);                      
            }

            /* move our pointer up to the beginning of the next object */
            pTableData += SIZE_OF_TRACKED_OBJECT;
        }
                
                /* all done...send the end of tracking packets char */
                UIMgr_writeTxFifo(0xFF);
        }       
#endif  

    /* the tracked object table will be cleared out right before we start
    to wait for VSYNC to indicate a new frame...so it doesn't need to be
    done now */
    
        /* schedule the next action to acquire a new frame */   
        PUBLISH_EVENT(EV_PROCESS_FRAME_COMPLETE);
}

/***********************************************************
        Function Name: FrameMgr_findConnectedness
        Function Description: This function is responsible for
        finding the connectedness between two particular run-
        length encoded lines of pixel data.  It updates the
        trackingTable as needed.
        Inputs:  none
        Outputs: none
***********************************************************/    
static void FrameMgr_findConnectedness(void)
{
        trackedColor_t currColor;
        unsigned char *pCurrLineColorInfo = currentLineBuffer;
        unsigned char *pTrackedObjectData;
        register unsigned char currPixelRunStart=0;
        register unsigned char currPixelRunFinish=0; 
        register unsigned char lastLineXStart=0;
        register unsigned char lastLineXFinish=0;  
        register unsigned char runLength=1;
        unsigned char i;
        bool_t colorConnected;  
        
        do
        {
                /* grab both the current color and the number of pixels
                in the run...remember, pixels start at 1, not 0! */
                colorConnected = FALSE;
                currColor = *pCurrLineColorInfo++;
                currPixelRunStart += runLength;
                runLength = *pCurrLineColorInfo++;
                currPixelRunFinish += runLength;
      
        /* make sure that the run-length is at least as wide as
        the minimum horizontal tracking width, and we care about the color */ 
        
                if ( (currColor != notTracked) && (runLength > MIN_OBJECT_TRACKING_WIDTH) )
                {                       
            /* this run contains a color we care about, so 
                        either it will begin a new tracked object, or it
                        is connected to a currently tracked object...
                        compare it with each object in the tracking
                        table...we can't just look at the numTrackedObjects because
            it is entirely possible that the first couple of objects could
            be invalid...

            NOTE: Instead of accessing each element in the trackedObjectTable
            through the 'i' index, and then accessing the fields in each structure,
            a pointer to each entry is established each time through the loop, followed
            by accessing the elements through specified offsets.  GCC seems to be
            able to optimize this code much better than simply accessing the elements
            of each structure in the array the more normal way...*/
            
            pTrackedObjectData = (unsigned char *)pCurrentTrackedObjectTable;
                        for (i=0; i<MAX_TRACKED_OBJECTS; i++)
                        {
                                if ( (currColor == *(pTrackedObjectData + COLOR_OFFSET)) && 
                     (*(pTrackedObjectData + VALID_OBJECT_OFFSET) == TRUE) &&
                     (*(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET) == trackedLineCount - 1) &&
                    /* add a check to limit the vertical size of object to 18 pixels...this will help segment the
                       image for the purpose of tracking a line for the Chibots contest */
                     ( (*(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET) - (*(pTrackedObjectData + Y_UPPER_LEFT_OFFSET) ) ) < 18) )                       
                                {
                                        /* found a color match and the object is valid...check to see if there is
                                        connectedness */
                                        lastLineXStart = *(pTrackedObjectData + LAST_LINE_X_START_OFFSET);
                                        lastLineXFinish = *(pTrackedObjectData + LAST_LINE_X_FINISH_OFFSET);
                                        
                                        /* Check for the 5 following types of line connectedness:
                                        ---------------------
                                        |                   |
                                        ---------------------
                                                 -------------------------
                                                         |                       |
                                                         -------------------------  */
                                        if ( (  (currPixelRunStart >= lastLineXStart) &&
                                                        (currPixelRunStart <= lastLineXFinish) )  ||
                                                        
                                        /*               ---------------------
                                                         |                   |
                                                                         ---------------------
                                                -------------------
                                                |                 |
                                                -------------------  
                                                                   OR
                                                     ------------------------------
                                                         |                            |
                                                         ------------------------------
                                                                      ---------
                                                                                  |       |
                                                                                  ---------  */
                                                 (      (currPixelRunFinish >= lastLineXStart) && 
                                                        (currPixelRunFinish <= lastLineXFinish) ) ||
                                                        
                                                        
                                        /*     -------------------------------
                                               |                             |
                                                   -------------------------------
                                                   -------------------------------
                                                   |                             |
                                                   -------------------------------
                                                                  OR
                                                                     -------------
                                                                         |           |
                                                                         -------------
                                                        -------------------------------
                                                        |                             |
                                                        -------------------------------   */
                                                 (  (currPixelRunStart <= lastLineXStart) &&
                                                        (currPixelRunFinish >= lastLineXFinish) ) )
                                        {
                                                /* THERE IS CONNECTEDNESS...update the lastLineXStart and lastLineXFinish
                                                data pointed to by pTrackedObjectData */
                                                *(pTrackedObjectData + LAST_LINE_X_START_OFFSET) = currPixelRunStart;
                                                *(pTrackedObjectData + LAST_LINE_X_FINISH_OFFSET) = currPixelRunFinish;
                                                
                                                /* check if the bounding box needs to be updated */
                                                if (*(pTrackedObjectData + X_UPPER_LEFT_OFFSET) > currPixelRunStart)
                                                {
                                                        /* need to update the bounding box for the upper left point to 
                                                        enclose this new left-most point...we never have to update the
                                                        upper left Y point, since each scan line we process moves from
                                                        top to bottom */
                                                        *(pTrackedObjectData + X_UPPER_LEFT_OFFSET) = currPixelRunStart;
                                                }

                                                if ( *(pTrackedObjectData + X_LOWER_RIGHT_OFFSET) < currPixelRunFinish)
                                                {
                                                        /* need to update the bounding box for the lower right X point to
                                                        enclose this new right-most point */
                                                        *(pTrackedObjectData + X_LOWER_RIGHT_OFFSET) = currPixelRunFinish;
                                                }
                                                
                                                /* the lower right 'y' point always gets updated when connectedness is found */
                                                *(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET) = trackedLineCount;
                                                
                                                /* set a flag indicating that that color run is part of another
                                                object and thus doesn't need to be added as a new entry into the
                                                tracking table */
                                                colorConnected = TRUE;
                                                break;
                                        }
                                }
                
                /* go to the next object */
                pTrackedObjectData += SIZE_OF_TRACKED_OBJECT;
                        }
                        
                        if (colorConnected == FALSE)
                        {
                                /* a new entry needs to be made to the tracking table, since we have
                                a run-length with a color, and it isn't connected to anything...but we
                                can only do this if there is space left in the trackedObject table */
                                if (numCurrTrackedObjects < MAX_TRACKED_OBJECTS)
                                {                
                    /* space is available...add the object...but first we need to find an
                    invalid object in the object tracking table */
                    pTrackedObjectData = (unsigned char *)pCurrentTrackedObjectTable;
                    for (i=0; i<MAX_TRACKED_OBJECTS; i++)
                    {
                        if ( *(pTrackedObjectData + VALID_OBJECT_OFFSET) == FALSE)  break;
                        
                        /* if we haven't broken above, then the object must have been valid...
                        go ahead and move the pointer to the next object to check it */
                        pTrackedObjectData += SIZE_OF_TRACKED_OBJECT;
                    }
                    
                                        
                                        /* now that we have a pointer to the tracked object to be updated, update all
                                        the fields */
                                        *(pTrackedObjectData + COLOR_OFFSET)                = currColor;                        /* color */
                                        *(pTrackedObjectData + LAST_LINE_X_START_OFFSET)    = currPixelRunStart;        /* lastLineXStart */
                                        *(pTrackedObjectData + LAST_LINE_X_FINISH_OFFSET)   = currPixelRunFinish;       /* lastLineXFinish */
                                        *(pTrackedObjectData + X_UPPER_LEFT_OFFSET)         = currPixelRunStart;        /* x_upperLeft */
                                        *(pTrackedObjectData + Y_UPPER_LEFT_OFFSET)         = trackedLineCount; /* y_upperLeft */
                                        *(pTrackedObjectData + X_LOWER_RIGHT_OFFSET)        = currPixelRunFinish;       /* x_lowerRight */
                                        *(pTrackedObjectData + Y_LOWER_RIGHT_OFFSET)        = trackedLineCount; /* y_lowerRight */
                    *(pTrackedObjectData + VALID_OBJECT_OFFSET)         = TRUE;                /* objectValid flag */
                                                
                                        numCurrTrackedObjects++;
                                }
                        }
            
            /* move the pointer to the beginning of the next tracked object */
            pTrackedObjectData += SIZE_OF_TRACKED_OBJECT;
                }
        } while(currPixelRunFinish < ACTUAL_NUM_PIXELS_IN_A_LINE);
}