li_recognizer.c

开放源码实时操作系统源码.

li_recognizer_load_dictionary(recognizer rec,char* directory,char* name)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Dictionaries are not supported by the LI recognizer";

  return(NULL);

}

static int
li_recognizer_save_dictionary(recognizer rec,
			       char* directory,
			       char* name,
			       wordset dict)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Dictionaries are not supported by the LI recognizer";

  return(-1);

}

static int
li_recognizer_free_dictionary(recognizer rec,wordset dict)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Dictionaries are not supported by the LI recognizer";

  return(-1);

}

static int
li_recognizer_add_to_dictionary(recognizer rec,letterset* word,wordset dict)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Dictionaries are not supported by the LI recognizer";

  return(-1);

}

static int
li_recognizer_delete_from_dictionary(recognizer rec,
				      letterset* word,
				      wordset dict)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Dictionaries are not supported by the LI recognizer";

  return(-1);

}

static char*
li_recognizer_error(recognizer rec)
{
    char* ret = li_err_msg;

    /*Check for LI recognizer.*/

    if( !CHECK_LI_MAGIC(rec->recognizer_specific) ) {
	li_err_msg = "Not a LI recognizer";
	return(NULL);
    }

    li_err_msg = NULL;

    return(ret);
}

static int 
li_recognizer_clear(recognizer r,bool delete_points_p)
{
    li_recognizer* rec; 

    rec = (li_recognizer*)r->recognizer_specific;

    /*Check for LI recognizer.*/

    if( !CHECK_LI_MAGIC(rec) ) {
	li_err_msg = "Not a LI recognizer";
	return(0);
    }
  
    return(0);
}

static int 
li_recognizer_set_context(recognizer r,rc* rec_xt)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Contexts are not supported by the LI recognizer";

  return(-1);
}

static rc*
li_recognizer_get_context(recognizer r)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Contexts are not supported by the LI recognizer";

  return(NULL);
}

static int 
li_recognizer_get_buffer(recognizer r, u_int* nstrokes,pen_stroke** strokes)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Buffer get/set are not supported by the LI recognizer";

  return(-1);
}

static int 
li_recognizer_set_buffer(recognizer r,u_int nstrokes,pen_stroke* strokes)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Buffer get/set are not supported by the LI recognizer";

  return(-1);
}

static int
li_recognizer_translate(recognizer r,
			 u_int ncs,
			 pen_stroke* tps,
			 bool correlate_p,
			 int* nret,
			 rec_alternative** ret)
{
    char* clss = NULL;
    li_recognizer* rec; 
    int conf;
    rClassifier* rc;
      
    rec = (li_recognizer*)r->recognizer_specific;

    *nret = 0;
    *ret = NULL;

    /*Check for LI recognizer.*/

    if( !CHECK_LI_MAGIC(rec) ) {
	li_err_msg = "Not a LI recognizer";
	return(-1);
    }

   rc = &(rec->li_rc);

    /*Check for valid parameters.*/
    if (ncs < 1) {
	li_err_msg = "Invalid parameters: ncs";
	return(-1);
    }
    if( tps == NULL) {
	li_err_msg = "Invalid parameters: tps";
	return(-1);
    }
    if( nret == NULL) {
	li_err_msg = "Invalid parameters: nret";
	return(-1);
    }
    if( ret == NULL) {
	li_err_msg = "Invalid parameters: ret";
	return(-1);
    }

/*    if( ncs < 1 || tps == NULL || nret == NULL || ret == NULL) {
	li_err_msg = "Invalid parameters";
	return(-1);
    }
*/

    /*Check for null classifier. It must have at least one.*/
/*
    if( rec->li_rc.sc == NULL ) {
	li_err_msg = "No classifier";
	return(-1);
    }
*/

    /*
     * Go through the stroke array and recognize. Since this is a single
     *   stroke recognizer, each stroke is treated as a separate
     *   character or gesture. We allow only characters or gestures
     *   to be recognized at one time, since otherwise, handling
     *   the display of segmentation would be difficult. 
    */
    clss = recognize_internal(rc,tps,&conf);
    if (clss == NULL) {
/*
	li_err_msg = "unrecognized character";
	return(-1);
*/
	*nret = 1;
	return(0);
    }

    /*Return values.*/
    *nret = 1;
    return(*clss);
}


static rec_fn*
li_recognizer_get_extension_functions(recognizer rec)
{
    rec_fn* ret;

    /*Check for LI recognizer.*/

    if( !CHECK_LI_MAGIC(rec->recognizer_specific) ) {
	li_err_msg = "Not a LI recognizer";
	return(NULL);
    }

    ret = make_rec_fn_array(LI_NUM_EX_FNS);

/* ari -- clearState & getClasses are mine */
    ret[LI_GET_CLASSES] = (rec_fn)recognizer_getClasses;
    ret[LI_CLEAR] = (rec_fn)recognizer_clearState;
    ret[LI_ISA_LI] = (rec_fn)isa_li;
    ret[LI_TRAIN] = (rec_fn)recognizer_train;

    return(ret);
}

static char**
li_recognizer_get_gesture_names(recognizer r)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Gestures are not supported by the LI recognizer";

  return(NULL);
}

static xgesture
li_recognizer_set_gesture_action(recognizer r,
				  char* name,
				  xgesture fn,
				  void* wsinfo)
{
  /*This operation isn't supported by the LI recognizer.*/

  li_err_msg = "Gestures are not supported by the LI recognizer";

  return(NULL);
}

/*
 * Exported Functions
*/

/*RECOGNIZER_INITIALIZE-Initialize the recognizer.*/

/* note from ari:  this expands via pre-processor to
 *
 * recognizer __recognizer_internal_initialize(rec_info* ri)
*/

RECOGNIZER_INITIALIZE(ri)
{
    recognizer r;
    li_recognizer* rec;
    int i;

    /*Check that locale matches.*/

    if( strcmp(ri->ri_locale,LI_SUPPORTED_LOCALE) != 0 ) {
	li_err_msg = "Not a supported locale";
fprintf(stderr, "Locale error.\n");
#if 0
	return(NULL);
#endif
    }

    /*
     * Check that character sets match. Note that this is only approximate,
     * since the classifier file will have more information.
    */

    if( ri->ri_subset != NULL ) {
      for(i = 0; ri->ri_subset[i] != NULL; i++ ) {

	if( strcmp(ri->ri_subset[i],UPPERCASE) != 0 &&
	    strcmp(ri->ri_subset[i],LOWERCASE) != 0  &&
	    strcmp(ri->ri_subset[i],DIGITS) != 0 &&
	    strcmp(ri->ri_subset[i],GESTURE) != 0 ) {
	  li_err_msg = "Not a supported character set";
fprintf(stderr, "charset error.\n");

	  return(NULL);
	}
      }
    }
	     
/* ari */
    r = make_recognizer(ri);
    /*fprintf(stderr, "past make_recognizer.\n");*/

    if( r == NULL ) {
	li_err_msg = "Can't allocate storage";

	return(NULL);
    }

    /*Make a LI recognizer structure.*/


    /* rec = (li_recognizer*)safe_malloc(sizeof(li_recognizer))) == NULL ); */

    rec = allocate(1, li_recognizer);

    r->recognizer_specific = rec;

    rec->li_rc.file_name = NULL;
    rec->li_rc.sc = NULL;

    /*Initialize the recognizer struct.*/

    r->recognizer_load_state = li_recognizer_load;
    r->recognizer_save_state = li_recognizer_save;
    r->recognizer_load_dictionary = li_recognizer_load_dictionary;
    r->recognizer_save_dictionary = li_recognizer_save_dictionary;
    r->recognizer_free_dictionary = li_recognizer_free_dictionary;
    r->recognizer_add_to_dictionary = li_recognizer_add_to_dictionary;
    r->recognizer_delete_from_dictionary = li_recognizer_delete_from_dictionary;
    r->recognizer_error = li_recognizer_error;
    r->recognizer_translate = li_recognizer_translate;
    r->recognizer_get_context = li_recognizer_get_context;
    r->recognizer_set_context = li_recognizer_set_context;
    r->recognizer_get_buffer = li_recognizer_get_buffer;
    r->recognizer_set_buffer = li_recognizer_set_buffer;
    r->recognizer_clear = li_recognizer_clear;
    r->recognizer_get_extension_functions = 
      li_recognizer_get_extension_functions;
    r->recognizer_get_gesture_names = li_recognizer_get_gesture_names;
    r->recognizer_set_gesture_action = 
      li_recognizer_set_gesture_action;

    /*Initialize LI Magic Number.*/

    rec->li_magic = LI_MAGIC;

    /*Initialize rClassifier.*/

    rec->li_rc.file_name = NULL;

    for( i = 0; i < MAXSCLASSES; i++ ) {
	rec->li_rc.ex[i] = NULL;
	rec->li_rc.cnames[i] = NULL;
    }

    lialg_initialize(&rec->li_rc);

    /*Get rid of error message. Not needed here.*/
    li_err_msg = NULL;

    return(r);
}

/*free_rClassifier-Free the rClassifier.*/

static void
free_rClassifier(rClassifier* rc)
{
    int i;

    if( rc->file_name != NULL) {
	free(rc->file_name);
    }

    for( i = 0; rc->ex[i] != NULL; i++) {
	delete_examples(rc->ex[i]);
	free(rc->cnames[i]);
    }

    if(rc->sc != NULL ) {
	sFreeClassifier(rc->sc);
    }
}

/*RECOGNIZER_FINALIZE-Deallocate the recognizer, finalize.*/

RECOGNIZER_FINALIZE(r)
{
    li_recognizer* rec = (li_recognizer*)r->recognizer_specific;

    /*Make sure this is a li_recognizer first*/

    if( !CHECK_LI_MAGIC(rec) ) {
	li_err_msg = "Not a LI recognizer";
	return(-1);
    }

    /*Deallocate rClassifier resources.*/

    free_rClassifier(&(rec->li_rc));

    /*Deallocate the li_recognizer struct.*/

    free(rec);

    /*Deallocate the recognizer*/

    delete_recognizer(r);

    return(0);
}


/* **************************************************

  Implementation of the Li/Yeung recognition algorithm

************************************************** */

/*#include <assert.h>*/
#ifdef __ECOS
#define MAXINT 0x7FFFFFFF
#else
#include <values.h>
#endif
#include <sys/time.h>

#ifdef	__ultrix
/* Ultrix doesn't have these declarations in math.h! */
extern double rint(double);
extern float expf(float);
#endif

#ifdef	ELX
extern double rint (double);
extern float expf (float);	/* N.B.  exp() appears to be broken on ELX! */
#endif

#define	WORST_SCORE	MAXINT

/* Dynamic programming parameters */
#define	DP_BAND		3
#define	MIN_SIM		0
#define	MAX_DIST	MAXINT
#define	SIM_THLD	60	/* x 100 */
#define	DIST_THLD	3200	/* x 100 */

/* Low-pass filter parameters -- empirically derived */
#define	LP_FILTER_WIDTH	6
#define	LP_FILTER_ITERS	8
#define	LP_FILTER_THLD	250	/* x 100 */
#define	LP_FILTER_MIN	5

/* Pseudo-extrema parameters -- empirically derived */
#define	PE_AL_THLD	1500	/* x 100 */
#define	PE_ATCR_THLD	135	/* x 100 */

/* Contour-angle derivation parameters */
#define	T_ONE		1
#define	T_TWO		20

/* Pre-processing and canonicalization parameters */
#define	CANONICAL_X	108
#define	CANONICAL_Y	128
#define	DIST_SQ_THRESHOLD   (3*3)	/* copied from fv.h */
#define	NCANONICAL	50

/* Tap-handling parameters */
#define	TAP_CHAR	"."
#define	TAP_TIME_THLD	150	    /* msec */
#define	TAP_DIST_THLD	75	    /* dx * dx + dy * dy */
#define	TAP_PATHLEN	1000	    /* x 100 */


/* Overload the time field of the pen_point struct with the chain-code. */
#define	chaincode   time

/* region types */
#define	RGN_CONVEX  0
#define	RGN_CONCAVE 1
#define	RGN_PLAIN   2
#define	RGN_PSEUDO  3


typedef struct RegionList {
    int start;
    int end;
    int type;
    struct RegionList *next;
} region_list;


/* direction-code table; indexed by dx, dy */
static int lialg_dctbl[3][3] = {{1, 0, 7}, {2, 0x7FFFFFFF, 6}, {3, 4, 5}};

/* low-pass filter weights */
static int lialg_lpfwts[2 * LP_FILTER_WIDTH + 1];
static int lialg_lpfconst = -1;