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/*

    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) )

				{

					/* 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);

}