#include "allheaders.h"
/* There are two methods for splitting characters: DID and greedy.
* The default method is DID. */
#define SPLIT_WITH_DID 1
/* Padding on pix1: added before correlations and removed from result */
static const l_int32 LeftRightPadding = 32;
/* Parameters for filtering and sorting connected components in splitter */
static const l_float32 MinFillFactor = 0.10;
static const l_int32 DefaultMinHeight = 15; /* min unscaled height */
static const l_int32 MinOverlap1 = 6; /* in pass 1 of boxaSort2d() */
static const l_int32 MinOverlap2 = 6; /* in pass 2 of boxaSort2d() */
static const l_int32 MinHeightPass1 = 5; /* min height to start pass 1 */
static l_int32 pixCorrelationBestShift(PIX *pix1, PIX *pix2, NUMA *nasum1,
NUMA *namoment1, l_int32 area2,
l_int32 ycent2, l_int32 maxyshift,
l_int32 *tab8, l_int32 *pdelx,
l_int32 *pdely, l_float32 *pscore,
l_int32 debugflag );
static L_RCH *rchCreate(l_int32 index, l_float32 score, char *text,
l_int32 sample, l_int32 xloc, l_int32 yloc,
l_int32 width);
static L_RCHA *rchaCreate();
static l_int32 transferRchToRcha(L_RCH *rch, L_RCHA *rcha);
static PIX *recogPreSplittingFilter(L_RECOG *recog, PIX *pixs, l_int32 minh,
l_float32 minaf, l_int32 debug);
static l_int32 recogSplittingFilter(L_RECOG *recog, PIX *pixs, l_int32 min,
l_float32 minaf, l_int32 *premove,
l_int32 debug);
static void l_showIndicatorSplitValues(NUMA *na1, NUMA *na2, NUMA *na3,
NUMA *na4, NUMA *na5, NUMA *na6);
/*------------------------------------------------------------------------*
* Identification
*------------------------------------------------------------------------*/
/*!
* \brief recogIdentifyMultiple()
*
* \param[in] recog with training finished
* \param[in] pixs containing typically a small number of characters
* \param[in] minh remove shorter components; use 0 for default
* \param[in] skipsplit 1 to skip the splitting step
* \param[out] pboxa [optional] locations of identified components
* \param[out] ppixa [optional] images of identified components
* \param[out] ppixdb [optional] debug pix: inputs and best fits
* \param[in] debugsplit 1 returns pix split debugging images
* \return 0 if OK; 1 if nothing is found; 2 for other errors.
*
*
* Notes:
* (1) This filters the input pixa and calls recogIdentifyPixa()
* (2) Splitting is relatively slow, because it tries to match all
* character templates to all locations. This step can be skipped.
* (3) An attempt is made to order the (optionally) returned images
* and boxes in 2-dimensional sorted order. These can then
* be used to aggregate identified characters into numbers or words.
* One typically wants the pixa, which contains a boxa of the
* extracted subimages.
*
*/
l_ok
recogIdentifyMultiple(L_RECOG *recog,
PIX *pixs,
l_int32 minh,
l_int32 skipsplit,
BOXA **pboxa,
PIXA **ppixa,
PIX **ppixdb,
l_int32 debugsplit)
{
l_int32 n;
BOXA *boxa;
PIX *pixb;
PIXA *pixa;
PROCNAME("recogIdentifyMultiple");
if (pboxa) *pboxa = NULL;
if (ppixa) *ppixa = NULL;
if (ppixdb) *ppixdb = NULL;
if (!recog)
return ERROR_INT("recog not defined", procName, 2);
if (!recog->train_done)
return ERROR_INT("training not finished", procName, 2);
if (!pixs)
return ERROR_INT("pixs not defined", procName, 2);
/* Binarize if necessary */
if (pixGetDepth(pixs) > 1)
pixb = pixConvertTo1(pixs, recog->threshold);
else
pixb = pixClone(pixs);
/* Noise removal and splitting of touching characters */
recogSplitIntoCharacters(recog, pixb, minh, skipsplit, &boxa, &pixa,
debugsplit);
pixDestroy(&pixb);
if (!pixa || (n = pixaGetCount(pixa)) == 0) {
pixaDestroy(&pixa);
boxaDestroy(&boxa);
L_WARNING("nothing found\n", procName);
return 1;
}
recogIdentifyPixa(recog, pixa, ppixdb);
if (pboxa)
*pboxa = boxa;
else
boxaDestroy(&boxa);
if (ppixa)
*ppixa = pixa;
else
pixaDestroy(&pixa);
return 0;
}
/*------------------------------------------------------------------------*
* Segmentation and noise removal *
*------------------------------------------------------------------------*/
/*!
* \brief recogSplitIntoCharacters()
*
* \param[in] recog
* \param[in] pixs 1 bpp, contains only mostly deskewed text
* \param[in] minh remove shorter components; use 0 for default
* \param[in] skipsplit 1 to skip the splitting step
* \param[out] pboxa character bounding boxes
* \param[out] ppixa character images
* \param[in] debug 1 for results written to pixadb_split
* \return 0 if OK, 1 on error or if no components are returned
*
*
* Notes:
* (1) This can be given an image that has an arbitrary number
* of text characters. It optionally splits connected
* components based on document image decoding in recogDecode().
* The returned pixa includes the boxes from which the
* (possibly split) components are extracted.
* (2) After noise filtering, the resulting components are put in
* row-major (2D) order, and the smaller of overlapping
* components are removed if they satisfy conditions of
* relative size and fractional overlap.
* (3) Note that the splitting function uses unscaled templates
* and does not bother returning the class results and scores.
* These are more accurately found later using the scaled templates.
*
*/
l_ok
recogSplitIntoCharacters(L_RECOG *recog,
PIX *pixs,
l_int32 minh,
l_int32 skipsplit,
BOXA **pboxa,
PIXA **ppixa,
l_int32 debug)
{
static l_int32 ind = 0;
char buf[32];
l_int32 i, xoff, yoff, empty, maxw, bw, ncomp, scaling;
BOX *box;
BOXA *boxa1, *boxa2, *boxa3, *boxa4, *boxad;
BOXAA *baa;
PIX *pix, *pix1, *pix2, *pix3;
PIXA *pixa;
PROCNAME("recogSplitIntoCharacters");
lept_mkdir("lept/recog");
if (pboxa) *pboxa = NULL;
if (ppixa) *ppixa = NULL;
if (!pboxa || !ppixa)
return ERROR_INT("&boxa and &pixa not defined", procName, 1);
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!recog->train_done)
return ERROR_INT("training not finished", procName, 1);
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
if (minh <= 0) minh = DefaultMinHeight;
pixZero(pixs, &empty);
if (empty) return 1;
/* Small vertical close for consolidation. Don't do a horizontal
* closing, because it might join separate characters. */
pix1 = pixMorphSequence(pixs, "c1.3", 0);
/* Carefully filter out noise */
pix2 = recogPreSplittingFilter(recog, pix1, minh, MinFillFactor, debug);
pixDestroy(&pix1);
/* Get the 8-connected components to be split/identified */
boxa1 = pixConnComp(pix2, NULL, 8);
pixDestroy(&pix2);
ncomp = boxaGetCount(boxa1);
if (ncomp == 0) {
boxaDestroy(&boxa1);
L_WARNING("all components removed\n", procName);
return 1;
}
/* Save everything and split the large components */
boxa2 = boxaCreate(ncomp);
maxw = recog->maxwidth_u + 5;
scaling = (recog->scalew > 0 || recog->scaleh > 0) ? TRUE : FALSE;
pixa = (debug) ? pixaCreate(ncomp) : NULL;
for (i = 0; i < ncomp; i++) {
box = boxaGetBox(boxa1, i, L_CLONE);
boxGetGeometry(box, &xoff, &yoff, &bw, NULL);
/* Treat as one character if it is small, if the images
* have been scaled, or if splitting is not to be run. */
if (bw <= maxw || scaling || skipsplit) {
boxaAddBox(boxa2, box, L_INSERT);
} else {
pix = pixClipRectangle(pixs, box, NULL);
#if SPLIT_WITH_DID
if (!debug) {
boxa3 = recogDecode(recog, pix, 2, NULL);
} else {
boxa3 = recogDecode(recog, pix, 2, &pix2);
pixaAddPix(pixa, pix2, L_INSERT);
}
#else /* use greedy splitting */
recogCorrelationBestRow(recog, pix, &boxa3, NULL, NULL,
NULL, debug);
if (debug) {
pix2 = pixConvertTo32(pix);
pixRenderBoxaArb(pix2, boxa3, 2, 255, 0, 0);
pixaAddPix(pixa, pix2, L_INSERT);
}
#endif /* SPLIT_WITH_DID */
pixDestroy(&pix);
boxDestroy(&box);
if (!boxa3) {
L_ERROR("boxa3 not found for component %d\n", procName, i);
} else {
boxa4 = boxaTransform(boxa3, xoff, yoff, 1.0, 1.0);
boxaJoin(boxa2, boxa4, 0, -1);
boxaDestroy(&boxa3);
boxaDestroy(&boxa4);
}
}
}
boxaDestroy(&boxa1);
if (pixa) { /* debug */
pix3 = pixaDisplayTiledInColumns(pixa, 1, 1.0, 20, 2);
snprintf(buf, sizeof(buf), "/tmp/lept/recog/decode-%d.png", ind++);
pixWrite(buf, pix3, IFF_PNG);
pixaDestroy(&pixa);
pixDestroy(&pix3);
}
/* Do a 2D sort on the bounding boxes, and flatten the result to 1D.
* For the 2D sort, to add a box to an existing boxa, we require
* specified minimum vertical overlaps for the first two passes
* of the 2D sort. In pass 1, only components with sufficient
* height can start a new boxa. */
baa = boxaSort2d(boxa2, NULL, MinOverlap1, MinOverlap2, MinHeightPass1);
boxa3 = boxaaFlattenToBoxa(baa, NULL, L_CLONE);
boxaaDestroy(&baa);
boxaDestroy(&boxa2);
/* Remove smaller components of overlapping pairs.
* We only remove the small component if the overlap is
* at least half its area and if its area is no more
* than 30% of the area of the large component. Because the
* components are in a flattened 2D sort, we don't need to
* look far ahead in the array to find all overlapping boxes;
* 10 boxes is plenty. */
boxad = boxaHandleOverlaps(boxa3, L_COMBINE, 10, 0.5, 0.3, NULL);
boxaDestroy(&boxa3);
/* Extract and save the image pieces from the input image. */
*ppixa = pixClipRectangles(pixs, boxad);
*pboxa = boxad;
return 0;
}
/*------------------------------------------------------------------------*
* Greedy character splitting *
*------------------------------------------------------------------------*/
/*!
* \brief recogCorrelationBestRow()
*
* \param[in] recog with LUT's pre-computed
* \param[in] pixs typically of multiple touching characters, 1 bpp
* \param[out] pboxa bounding boxs of best fit character
* \param[out] pnascore [optional] correlation scores
* \param[out] pnaindex [optional] indices of classes
* \param[out] psachar [optional] array of character strings
* \param[in] debug 1 for results written to pixadb_split
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) Supervises character matching for (in general) a c.c with
* multiple touching characters. Finds the best match greedily.
* Rejects small parts that are left over after splitting.
* (2) Matching is to the average, and without character scaling.
*
*/
l_ok
recogCorrelationBestRow(L_RECOG *recog,
PIX *pixs,
BOXA **pboxa,
NUMA **pnascore,
NUMA **pnaindex,
SARRAY **psachar,
l_int32 debug)
{
char *charstr;
l_int32 index, remove, w, h, bx, bw, bxc, bwc, w1, w2, w3;
l_float32 score;
BOX *box, *boxc, *boxtrans, *boxl, *boxr, *boxlt, *boxrt;
BOXA *boxat;
NUMA *nascoret, *naindext, *nasort;
PIX *pixb, *pixc, *pixl, *pixr, *pixdb, *pixd;
PIXA *pixar, *pixadb;
SARRAY *sachart;
l_int32 iter;
PROCNAME("recogCorrelationBestRow");
if (pnascore) *pnascore = NULL;
if (pnaindex) *pnaindex = NULL;
if (psachar) *psachar = NULL;
if (!pboxa)
return ERROR_INT("&boxa not defined", procName, 1);
*pboxa = NULL;
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
if (pixGetWidth(pixs) < recog->minwidth_u - 4)
return ERROR_INT("pixs too narrow", procName, 1);
if (!recog->train_done)
return ERROR_INT("training not finished", procName, 1);
/* Binarize and crop to foreground if necessary */
pixb = recogProcessToIdentify(recog, pixs, 0);
/* Initialize the arrays */
boxat = boxaCreate(4);
nascoret = numaCreate(4);
naindext = numaCreate(4);
sachart = sarrayCreate(4);
pixadb = (debug) ? pixaCreate(4) : NULL;
/* Initialize the images remaining to be processed with the input.
* These are stored in pixar, which is used here as a queue,
* on which we only put image fragments that are large enough to
* contain at least one character. */
pixar = pixaCreate(1);
pixGetDimensions(pixb, &w, &h, NULL);
box = boxCreate(0, 0, w, h);
pixaAddPix(pixar, pixb, L_INSERT);
pixaAddBox(pixar, box, L_INSERT);
/* Successively split on the best match until nothing is left.
* To be safe, we limit the search to 10 characters. */
for (iter = 0; iter < 11; iter++) {
if (pixaGetCount(pixar) == 0)
break;
if (iter == 10) {
L_WARNING("more than 10 chars; ending search\n", procName);
break;
}
/* Pop one from the queue */
pixaRemovePixAndSave(pixar, 0, &pixc, &boxc);
boxGetGeometry(boxc, &bxc, NULL, &bwc, NULL);
/* This is a single component; if noise, remove it */
recogSplittingFilter(recog, pixc, 0, MinFillFactor, &remove, debug);
if (debug)
lept_stderr("iter = %d, removed = %d\n", iter, remove);
if (remove) {
pixDestroy(&pixc);
boxDestroy(&boxc);
continue;
}
/* Find the best character match */
if (debug) {
recogCorrelationBestChar(recog, pixc, &box, &score,
&index, &charstr, &pixdb);
pixaAddPix(pixadb, pixdb, L_INSERT);
} else {
recogCorrelationBestChar(recog, pixc, &box, &score,
&index, &charstr, NULL);
}
/* Find the box in original coordinates, and append
* the results to the arrays. */
boxtrans = boxTransform(box, bxc, 0, 1.0, 1.0);
boxaAddBox(boxat, boxtrans, L_INSERT);
numaAddNumber(nascoret, score);
numaAddNumber(naindext, index);
sarrayAddString(sachart, charstr, L_INSERT);
/* Split the current pixc into three regions and save
* each region if it is large enough. */
boxGetGeometry(box, &bx, NULL, &bw, NULL);
w1 = bx;
w2 = bw;
w3 = bwc - bx - bw;
if (debug)
lept_stderr(" w1 = %d, w2 = %d, w3 = %d\n", w1, w2, w3);
if (w1 < recog->minwidth_u - 4) {
if (debug) L_INFO("discarding width %d on left\n", procName, w1);
} else { /* extract and save left region */
boxl = boxCreate(0, 0, bx + 1, h);
pixl = pixClipRectangle(pixc, boxl, NULL);
boxlt = boxTransform(boxl, bxc, 0, 1.0, 1.0);
pixaAddPix(pixar, pixl, L_INSERT);
pixaAddBox(pixar, boxlt, L_INSERT);
boxDestroy(&boxl);
}
if (w3 < recog->minwidth_u - 4) {
if (debug) L_INFO("discarding width %d on right\n", procName, w3);
} else { /* extract and save left region */
boxr = boxCreate(bx + bw - 1, 0, w3 + 1, h);
pixr = pixClipRectangle(pixc, boxr, NULL);
boxrt = boxTransform(boxr, bxc, 0, 1.0, 1.0);
pixaAddPix(pixar, pixr, L_INSERT);
pixaAddBox(pixar, boxrt, L_INSERT);
boxDestroy(&boxr);
}
pixDestroy(&pixc);
boxDestroy(&box);
boxDestroy(&boxc);
}
pixaDestroy(&pixar);
/* Sort the output results by left-to-right in the boxa */
*pboxa = boxaSort(boxat, L_SORT_BY_X, L_SORT_INCREASING, &nasort);
if (pnascore)
*pnascore = numaSortByIndex(nascoret, nasort);
if (pnaindex)
*pnaindex = numaSortByIndex(naindext, nasort);
if (psachar)
*psachar = sarraySortByIndex(sachart, nasort);
numaDestroy(&nasort);
boxaDestroy(&boxat);
numaDestroy(&nascoret);
numaDestroy(&naindext);
sarrayDestroy(&sachart);
/* Final debug output */
if (debug) {
pixd = pixaDisplayTiledInRows(pixadb, 32, 2000, 1.0, 0, 15, 2);
pixDisplay(pixd, 400, 400);
pixaAddPix(recog->pixadb_split, pixd, L_INSERT);
pixaDestroy(&pixadb);
}
return 0;
}
/*!
* \brief recogCorrelationBestChar()
*
* \param[in] recog with LUT's pre-computed
* \param[in] pixs can be of multiple touching characters, 1 bpp
* \param[out] pbox bounding box of best fit character
* \param[out] pscore correlation score
* \param[out] pindex [optional] index of class
* \param[out] pcharstr [optional] character string of class
* \param[out] ppixdb [optional] debug pix showing input and best fit
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) Basic matching character splitter. Finds the best match among
* all templates to some region of the image. This can result
* in splitting the image into two parts. This is "image decoding"
* without dynamic programming, because we don't use a setwidth
* and compute the best matching score for the entire image.
* (2) Matching is to the average templates, without character scaling.
*
*/
l_ok
recogCorrelationBestChar(L_RECOG *recog,
PIX *pixs,
BOX **pbox,
l_float32 *pscore,
l_int32 *pindex,
char **pcharstr,
PIX **ppixdb)
{
l_int32 i, n, w1, h1, w2, area2, ycent2, delx, dely;
l_int32 bestdelx, bestdely, bestindex;
l_float32 score, bestscore;
BOX *box;
BOXA *boxa;
NUMA *nasum, *namoment;
PIX *pix1, *pix2;
PROCNAME("recogCorrelationBestChar");
if (pindex) *pindex = 0;
if (pcharstr) *pcharstr = NULL;
if (ppixdb) *ppixdb = NULL;
if (pbox) *pbox = NULL;
if (pscore) *pscore = 0.0;
if (!pbox || !pscore)
return ERROR_INT("&box and &score not both defined", procName, 1);
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
if (!recog->train_done)
return ERROR_INT("training not finished", procName, 1);
/* Binarize and crop to foreground if necessary. Add padding
* to both the left and right side; this is compensated for
* when reporting the bounding box of the best matched character. */
pix1 = recogProcessToIdentify(recog, pixs, LeftRightPadding);
pixGetDimensions(pix1, &w1, &h1, NULL);
/* Compute vertical sum and moment arrays */
nasum = pixCountPixelsByColumn(pix1);
namoment = pixGetMomentByColumn(pix1, 1);
/* Do shifted correlation against all averaged templates. */
n = recog->setsize;
boxa = boxaCreate(n); /* location of best fits for each character */
bestscore = 0.0;
bestindex = bestdelx = bestdely = 0;
for (i = 0; i < n; i++) {
pix2 = pixaGetPix(recog->pixa_u, i, L_CLONE);
w2 = pixGetWidth(pix2);
/* Note that the slightly expended w1 is typically larger
* than w2 (the template). */
if (w1 >= w2) {
numaGetIValue(recog->nasum_u, i, &area2);
ptaGetIPt(recog->pta_u, i, NULL, &ycent2);
pixCorrelationBestShift(pix1, pix2, nasum, namoment, area2, ycent2,
recog->maxyshift, recog->sumtab, &delx,
&dely, &score, 1);
if (ppixdb) {
lept_stderr(
"Best match template %d: (x,y) = (%d,%d), score = %5.3f\n",
i, delx, dely, score);
}
/* Compensate for padding */
box = boxCreate(delx - LeftRightPadding, 0, w2, h1);
if (score > bestscore) {
bestscore = score;
bestdelx = delx - LeftRightPadding;
bestdely = dely;
bestindex = i;
}
} else {
box = boxCreate(0, 0, 1, 1); /* placeholder */
if (ppixdb)
lept_stderr("Component too thin: w1 = %d, w2 = %d\n", w1, w2);
}
boxaAddBox(boxa, box, L_INSERT);
pixDestroy(&pix2);
}
*pscore = bestscore;
*pbox = boxaGetBox(boxa, bestindex, L_COPY);
if (pindex) *pindex = bestindex;
if (pcharstr)
recogGetClassString(recog, bestindex, pcharstr);
if (ppixdb) {
L_INFO("Best match: class %d; shifts (%d, %d)\n",
procName, bestindex, bestdelx, bestdely);
pix2 = pixaGetPix(recog->pixa_u, bestindex, L_CLONE);
*ppixdb = recogShowMatch(recog, pix1, pix2, NULL, -1, 0.0);
pixDestroy(&pix2);
}
pixDestroy(&pix1);
boxaDestroy(&boxa);
numaDestroy(&nasum);
numaDestroy(&namoment);
return 0;
}
/*!
* \brief pixCorrelationBestShift()
*
* \param[in] pix1 1 bpp, the unknown image; typically larger
* \param[in] pix2 1 bpp, the matching template image)
* \param[in] nasum1 vertical column pixel sums for pix1
* \param[in] namoment1 vertical column first moment of pixels for pix1
* \param[in] area2 number of on pixels in pix2
* \param[in] ycent2 y component of centroid of pix2
* \param[in] maxyshift max y shift of pix2 around the location where
* the centroids of pix2 and a windowed part of pix1
* are vertically aligned
* \param[in] tab8 [optional] sum tab for ON pixels in byte;
* can be NULL
* \param[out] pdelx [optional] best x shift of pix2 relative to pix1
* \param[out] pdely [optional] best y shift of pix2 relative to pix1
* \param[out] pscore [optional] maximum score found; can be NULL
* \param[in] debugflag <= 0 to skip; positive to generate output;
* the integer is used to label the debug image.
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This maximizes the correlation score between two 1 bpp images,
* one of which is typically wider. In a typical example,
* pix1 is a bitmap of 2 or more touching characters and pix2 is
* a single character template. This finds the location of pix2
* that gives the largest correlation.
* (2) The windowed area of fg pixels and windowed first moment
* in the y direction are computed from the input sum and moment
* column arrays, %nasum1 and %namoment1
* (3) This is a brute force operation. We compute the correlation
* at every x shift for which pix2 fits entirely within pix1,
* and where the centroid of pix2 is aligned, within +-maxyshift,
* with the centroid of a window of pix1 of the same width.
* The correlation is taken over the full height of pix1.
* This can be made more efficient.
*
*/
static l_int32
pixCorrelationBestShift(PIX *pix1,
PIX *pix2,
NUMA *nasum1,
NUMA *namoment1,
l_int32 area2,
l_int32 ycent2,
l_int32 maxyshift,
l_int32 *tab8,
l_int32 *pdelx,
l_int32 *pdely,
l_float32 *pscore,
l_int32 debugflag)
{
l_int32 w1, w2, h1, h2, i, j, nx, shifty, delx, dely;
l_int32 sum, moment, count;
l_int32 *tab, *area1, *arraysum, *arraymoment;
l_float32 maxscore, score;
l_float32 *ycent1;
FPIX *fpix;
PIX *pixt, *pixt1, *pixt2;
PROCNAME("pixCorrelationBestShift");
if (pdelx) *pdelx = 0;
if (pdely) *pdely = 0;
if (pscore) *pscore = 0.0;
if (!pix1 || pixGetDepth(pix1) != 1)
return ERROR_INT("pix1 not defined or not 1 bpp", procName, 1);
if (!pix2 || pixGetDepth(pix2) != 1)
return ERROR_INT("pix2 not defined or not 1 bpp", procName, 1);
if (!nasum1 || !namoment1)
return ERROR_INT("nasum1 and namoment1 not both defined", procName, 1);
if (area2 <= 0 || ycent2 <= 0)
return ERROR_INT("area2 and ycent2 must be > 0", procName, 1);
/* If pix1 (the unknown image) is narrower than pix2,
* don't bother to try the match. pix1 is already padded with
* 2 pixels on each side. */
pixGetDimensions(pix1, &w1, &h1, NULL);
pixGetDimensions(pix2, &w2, &h2, NULL);
if (w1 < w2) {
if (debugflag > 0) {
L_INFO("skipping match with w1 = %d and w2 = %d\n",
procName, w1, w2);
}
return 0;
}
nx = w1 - w2 + 1;
if (debugflag > 0)
fpix = fpixCreate(nx, 2 * maxyshift + 1);
if (!tab8)
tab = makePixelSumTab8();
else
tab = tab8;
/* Set up the arrays for area1 and ycent1. We have to do this
* for each template (pix2) because the window width is w2. */
area1 = (l_int32 *)LEPT_CALLOC(nx, sizeof(l_int32));
ycent1 = (l_float32 *)LEPT_CALLOC(nx, sizeof(l_int32));
arraysum = numaGetIArray(nasum1);
arraymoment = numaGetIArray(namoment1);
for (i = 0, sum = 0, moment = 0; i < w2; i++) {
sum += arraysum[i];
moment += arraymoment[i];
}
for (i = 0; i < nx - 1; i++) {
area1[i] = sum;
ycent1[i] = (sum == 0) ? ycent2 : (l_float32)moment / (l_float32)sum;
sum += arraysum[w2 + i] - arraysum[i];
moment += arraymoment[w2 + i] - arraymoment[i];
}
area1[nx - 1] = sum;
ycent1[nx - 1] = (sum == 0) ? ycent2 : (l_float32)moment / (l_float32)sum;
/* Find the best match location for pix2. At each location,
* to insure that pixels are ON only within the intersection of
* pix and the shifted pix2:
* (1) Start with pixt cleared and equal in size to pix1.
* (2) Blit the shifted pix2 onto pixt. Then all ON pixels
* are within the intersection of pix1 and the shifted pix2.
* (3) AND pix1 with pixt. */
pixt = pixCreate(w2, h1, 1);
maxscore = 0;
delx = 0;
dely = 0; /* amount to shift pix2 relative to pix1 to get alignment */
for (i = 0; i < nx; i++) {
shifty = (l_int32)(ycent1[i] - ycent2 + 0.5);
for (j = -maxyshift; j <= maxyshift; j++) {
pixClearAll(pixt);
pixRasterop(pixt, 0, shifty + j, w2, h2, PIX_SRC, pix2, 0, 0);
pixRasterop(pixt, 0, 0, w2, h1, PIX_SRC & PIX_DST, pix1, i, 0);
pixCountPixels(pixt, &count, tab);
score = (l_float32)count * (l_float32)count /
((l_float32)area1[i] * (l_float32)area2);
if (score > maxscore) {
maxscore = score;
delx = i;
dely = shifty + j;
}
if (debugflag > 0)
fpixSetPixel(fpix, i, maxyshift + j, 1000.0 * score);
}
}
if (debugflag > 0) {
char buf[128];
lept_mkdir("lept/recog");
pixt1 = fpixDisplayMaxDynamicRange(fpix);
pixt2 = pixExpandReplicate(pixt1, 5);
snprintf(buf, sizeof(buf), "/tmp/lept/recog/junkbs_%d.png", debugflag);
pixWrite(buf, pixt2, IFF_PNG);
pixDestroy(&pixt1);
pixDestroy(&pixt2);
fpixDestroy(&fpix);
}
if (pdelx) *pdelx = delx;
if (pdely) *pdely = dely;
if (pscore) *pscore = maxscore;
if (!tab8) LEPT_FREE(tab);
LEPT_FREE(area1);
LEPT_FREE(ycent1);
LEPT_FREE(arraysum);
LEPT_FREE(arraymoment);
pixDestroy(&pixt);
return 0;
}
/*------------------------------------------------------------------------*
* Low-level identification *
*------------------------------------------------------------------------*/
/*!
* \brief recogIdentifyPixa()
*
* \param[in] recog
* \param[in] pixa of 1 bpp images to match
* \param[out] ppixdb [optional] pix showing inputs and best fits
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This should be called by recogIdentifyMuliple(), which
* binarizes and splits characters before sending %pixa here.
* (2) This calls recogIdentifyPix(), which does the same operation
* on each pix in %pixa, and optionally returns the arrays
* of results (scores, class index and character string)
* for the best correlation match.
*
*/
l_ok
recogIdentifyPixa(L_RECOG *recog,
PIXA *pixa,
PIX **ppixdb)
{
char *text;
l_int32 i, n, fail, index, depth;
l_float32 score;
PIX *pix1, *pix2, *pix3;
PIXA *pixa1;
L_RCH *rch;
PROCNAME("recogIdentifyPixa");
if (ppixdb) *ppixdb = NULL;
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!pixa)
return ERROR_INT("pixa not defined", procName, 1);
/* Run the recognizer on the set of images. This writes
* the text string into each pix in pixa. */
n = pixaGetCount(pixa);
rchaDestroy(&recog->rcha);
recog->rcha = rchaCreate();
pixa1 = (ppixdb) ? pixaCreate(n) : NULL;
depth = 1;
for (i = 0; i < n; i++) {
pix1 = pixaGetPix(pixa, i, L_CLONE);
pix2 = NULL;
fail = FALSE;
if (!ppixdb)
fail = recogIdentifyPix(recog, pix1, NULL);
else
fail = recogIdentifyPix(recog, pix1, &pix2);
if (fail)
recogSkipIdentify(recog);
if ((rch = recog->rch) == NULL) {
L_ERROR("rch not found for char %d\n", procName, i);
pixDestroy(&pix1);
pixDestroy(&pix2);
continue;
}
rchExtract(rch, NULL, NULL, &text, NULL, NULL, NULL, NULL);
pixSetText(pix1, text);
LEPT_FREE(text);
if (ppixdb) {
rchExtract(rch, &index, &score, NULL, NULL, NULL, NULL, NULL);
pix3 = recogShowMatch(recog, pix2, NULL, NULL, index, score);
if (i == 0) depth = pixGetDepth(pix3);
pixaAddPix(pixa1, pix3, L_INSERT);
pixDestroy(&pix2);
}
transferRchToRcha(rch, recog->rcha);
pixDestroy(&pix1);
}
/* Package the images for debug */
if (ppixdb) {
*ppixdb = pixaDisplayTiledInRows(pixa1, depth, 2500, 1.0, 0, 20, 1);
pixaDestroy(&pixa1);
}
return 0;
}
/*!
* \brief recogIdentifyPix()
*
* \param[in] recog with LUT's pre-computed
* \param[in] pixs of a single character, 1 bpp
* \param[out] ppixdb [optional] debug pix showing input and best fit
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) Basic recognition function for a single character.
* (2) If templ_use == L_USE_ALL_TEMPLATES, which is the default
* situation, matching is attempted to every bitmap in the recog,
* and the identify of the best match is returned.
* (3) For finding outliers, templ_use == L_USE_AVERAGE_TEMPLATES, and
* matching is only attemplted to the averaged bitmaps. For this
* case, the index of the bestsample is meaningless (0 is returned
* if requested).
* (4) The score is related to the confidence (probability of correct
* identification), in that a higher score is correlated with
* a higher probability. However, the actual relation between
* the correlation (score) and the probability is not known;
* we call this a "score" because "confidence" can be misinterpreted
* as an actual probability.
*
*/
l_ok
recogIdentifyPix(L_RECOG *recog,
PIX *pixs,
PIX **ppixdb)
{
char *text;
l_int32 i, j, n, bestindex, bestsample, area1, area2;
l_int32 shiftx, shifty, bestdelx, bestdely, bestwidth, maxyshift;
l_float32 x1, y1, x2, y2, delx, dely, score, maxscore;
NUMA *numa;
PIX *pix0, *pix1, *pix2;
PIXA *pixa;
PTA *pta;
PROCNAME("recogIdentifyPix");
if (ppixdb) *ppixdb = NULL;
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
/* Do the averaging if required and not yet done. */
if (recog->templ_use == L_USE_AVERAGE_TEMPLATES && !recog->ave_done) {
recogAverageSamples(&recog, 0);
if (!recog)
return ERROR_INT("averaging failed", procName, 1);
}
/* Binarize and crop to foreground if necessary */
if ((pix0 = recogProcessToIdentify(recog, pixs, 0)) == NULL)
return ERROR_INT("no fg pixels in pix0", procName, 1);
/* Optionally scale and/or convert to fixed stroke width */
pix1 = recogModifyTemplate(recog, pix0);
pixDestroy(&pix0);
if (!pix1)
return ERROR_INT("no fg pixels in pix1", procName, 1);
/* Do correlation at all positions within +-maxyshift of
* the nominal centroid alignment. */
pixCountPixels(pix1, &area1, recog->sumtab);
pixCentroid(pix1, recog->centtab, recog->sumtab, &x1, &y1);
bestindex = bestsample = bestdelx = bestdely = bestwidth = 0;
maxscore = 0.0;
maxyshift = recog->maxyshift;
if (recog->templ_use == L_USE_AVERAGE_TEMPLATES) {
for (i = 0; i < recog->setsize; i++) {
numaGetIValue(recog->nasum, i, &area2);
if (area2 == 0) continue; /* no template available */
pix2 = pixaGetPix(recog->pixa, i, L_CLONE);
ptaGetPt(recog->pta, i, &x2, &y2);
delx = x1 - x2;
dely = y1 - y2;
for (shifty = -maxyshift; shifty <= maxyshift; shifty++) {
for (shiftx = -maxyshift; shiftx <= maxyshift; shiftx++) {
pixCorrelationScoreSimple(pix1, pix2, area1, area2,
delx + shiftx, dely + shifty,
5, 5, recog->sumtab, &score);
if (score > maxscore) {
bestindex = i;
bestdelx = delx + shiftx;
bestdely = dely + shifty;
maxscore = score;
}
}
}
pixDestroy(&pix2);
}
} else { /* use all the samples */
for (i = 0; i < recog->setsize; i++) {
pixa = pixaaGetPixa(recog->pixaa, i, L_CLONE);
n = pixaGetCount(pixa);
if (n == 0) {
pixaDestroy(&pixa);
continue;
}
numa = numaaGetNuma(recog->naasum, i, L_CLONE);
pta = ptaaGetPta(recog->ptaa, i, L_CLONE);
for (j = 0; j < n; j++) {
pix2 = pixaGetPix(pixa, j, L_CLONE);
numaGetIValue(numa, j, &area2);
ptaGetPt(pta, j, &x2, &y2);
delx = x1 - x2;
dely = y1 - y2;
for (shifty = -maxyshift; shifty <= maxyshift; shifty++) {
for (shiftx = -maxyshift; shiftx <= maxyshift; shiftx++) {
pixCorrelationScoreSimple(pix1, pix2, area1, area2,
delx + shiftx, dely + shifty,
5, 5, recog->sumtab, &score);
if (score > maxscore) {
bestindex = i;
bestsample = j;
bestdelx = delx + shiftx;
bestdely = dely + shifty;
maxscore = score;
bestwidth = pixGetWidth(pix2);
}
}
}
pixDestroy(&pix2);
}
pixaDestroy(&pixa);
numaDestroy(&numa);
ptaDestroy(&pta);
}
}
/* Package up the results */
recogGetClassString(recog, bestindex, &text);
rchDestroy(&recog->rch);
recog->rch = rchCreate(bestindex, maxscore, text, bestsample,
bestdelx, bestdely, bestwidth);
if (ppixdb) {
if (recog->templ_use == L_USE_AVERAGE_TEMPLATES) {
L_INFO("Best match: str %s; class %d; sh (%d, %d); score %5.3f\n",
procName, text, bestindex, bestdelx, bestdely, maxscore);
pix2 = pixaGetPix(recog->pixa, bestindex, L_CLONE);
} else { /* L_USE_ALL_TEMPLATES */
L_INFO("Best match: str %s; sample %d in class %d; score %5.3f\n",
procName, text, bestsample, bestindex, maxscore);
if (maxyshift > 0 && (L_ABS(bestdelx) > 0 || L_ABS(bestdely) > 0)) {
L_INFO(" Best shift: (%d, %d)\n",
procName, bestdelx, bestdely);
}
pix2 = pixaaGetPix(recog->pixaa, bestindex, bestsample, L_CLONE);
}
*ppixdb = recogShowMatch(recog, pix1, pix2, NULL, -1, 0.0);
pixDestroy(&pix2);
}
pixDestroy(&pix1);
return 0;
}
/*!
* \brief recogSkipIdentify()
*
* \param[in] recog
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This just writes a "dummy" result with 0 score and empty
* string id into the rch.
*
*/
l_ok
recogSkipIdentify(L_RECOG *recog)
{
PROCNAME("recogSkipIdentify");
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
/* Package up placeholder results */
rchDestroy(&recog->rch);
recog->rch = rchCreate(0, 0.0, stringNew(""), 0, 0, 0, 0);
return 0;
}
/*------------------------------------------------------------------------*
* Operations for handling identification results *
*------------------------------------------------------------------------*/
/*!
* \brief rchaCreate()
*
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) Be sure to destroy any existing rcha before assigning this.
*/
static L_RCHA *
rchaCreate()
{
L_RCHA *rcha;
rcha = (L_RCHA *)LEPT_CALLOC(1, sizeof(L_RCHA));
rcha->naindex = numaCreate(0);
rcha->nascore = numaCreate(0);
rcha->satext = sarrayCreate(0);
rcha->nasample = numaCreate(0);
rcha->naxloc = numaCreate(0);
rcha->nayloc = numaCreate(0);
rcha->nawidth = numaCreate(0);
return rcha;
}
/*!
* \brief rchaDestroy()
*
* \param[in,out] prcha to be nulled
*/
void
rchaDestroy(L_RCHA **prcha)
{
L_RCHA *rcha;
PROCNAME("rchaDestroy");
if (prcha == NULL) {
L_WARNING("&rcha is null!\n", procName);
return;
}
if ((rcha = *prcha) == NULL)
return;
numaDestroy(&rcha->naindex);
numaDestroy(&rcha->nascore);
sarrayDestroy(&rcha->satext);
numaDestroy(&rcha->nasample);
numaDestroy(&rcha->naxloc);
numaDestroy(&rcha->nayloc);
numaDestroy(&rcha->nawidth);
LEPT_FREE(rcha);
*prcha = NULL;
}
/*!
* \brief rchCreate()
*
* \param[in] index index of best template
* \param[in] score correlation score of best template
* \param[in] text character string of best template
* \param[in] sample index of best sample; -1 if averages are used
* \param[in] xloc x-location of template: delx + shiftx
* \param[in] yloc y-location of template: dely + shifty
* \param[in] width width of best template
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) Be sure to destroy any existing rch before assigning this.
* (2) This stores the text string, not a copy of it, so the
* caller must not destroy the string.
*
*/
static L_RCH *
rchCreate(l_int32 index,
l_float32 score,
char *text,
l_int32 sample,
l_int32 xloc,
l_int32 yloc,
l_int32 width)
{
L_RCH *rch;
rch = (L_RCH *)LEPT_CALLOC(1, sizeof(L_RCH));
rch->index = index;
rch->score = score;
rch->text = text;
rch->sample = sample;
rch->xloc = xloc;
rch->yloc = yloc;
rch->width = width;
return rch;
}
/*!
* \brief rchDestroy()
*
* \param[in,out] prch to be nulled
*/
void
rchDestroy(L_RCH **prch)
{
L_RCH *rch;
PROCNAME("rchDestroy");
if (prch == NULL) {
L_WARNING("&rch is null!\n", procName);
return;
}
if ((rch = *prch) == NULL)
return;
LEPT_FREE(rch->text);
LEPT_FREE(rch);
*prch = NULL;
}
/*!
* \brief rchaExtract()
*
* \param[in] rcha
* \param[out] pnaindex [optional] indices of best templates
* \param[out] pnascore [optional] correl scores of best templates
* \param[out] psatext [optional] character strings of best templates
* \param[out] pnasample [optional] indices of best samples
* \param[out] pnaxloc [optional] x-locations of templates
* \param[out] pnayloc [optional] y-locations of templates
* \param[out] pnawidth [optional] widths of best templates
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This returns clones of the number and string arrays. They must
* be destroyed by the caller.
*
*/
l_ok
rchaExtract(L_RCHA *rcha,
NUMA **pnaindex,
NUMA **pnascore,
SARRAY **psatext,
NUMA **pnasample,
NUMA **pnaxloc,
NUMA **pnayloc,
NUMA **pnawidth)
{
PROCNAME("rchaExtract");
if (pnaindex) *pnaindex = NULL;
if (pnascore) *pnascore = NULL;
if (psatext) *psatext = NULL;
if (pnasample) *pnasample = NULL;
if (pnaxloc) *pnaxloc = NULL;
if (pnayloc) *pnayloc = NULL;
if (pnawidth) *pnawidth = NULL;
if (!rcha)
return ERROR_INT("rcha not defined", procName, 1);
if (pnaindex) *pnaindex = numaClone(rcha->naindex);
if (pnascore) *pnascore = numaClone(rcha->nascore);
if (psatext) *psatext = sarrayClone(rcha->satext);
if (pnasample) *pnasample = numaClone(rcha->nasample);
if (pnaxloc) *pnaxloc = numaClone(rcha->naxloc);
if (pnayloc) *pnayloc = numaClone(rcha->nayloc);
if (pnawidth) *pnawidth = numaClone(rcha->nawidth);
return 0;
}
/*!
* \brief rchExtract()
*
* \param[in] rch
* \param[out] pindex [optional] index of best template
* \param[out] pscore [optional] correlation score of best template
* \param[out] ptext [optional] character string of best template
* \param[out] psample [optional] index of best sample
* \param[out] pxloc [optional] x-location of template
* \param[out] pyloc [optional] y-location of template
* \param[out] pwidth [optional] width of best template
* \return 0 if OK, 1 on error
*/
l_ok
rchExtract(L_RCH *rch,
l_int32 *pindex,
l_float32 *pscore,
char **ptext,
l_int32 *psample,
l_int32 *pxloc,
l_int32 *pyloc,
l_int32 *pwidth)
{
PROCNAME("rchExtract");
if (pindex) *pindex = 0;
if (pscore) *pscore = 0.0;
if (ptext) *ptext = NULL;
if (psample) *psample = 0;
if (pxloc) *pxloc = 0;
if (pyloc) *pyloc = 0;
if (pwidth) *pwidth = 0;
if (!rch)
return ERROR_INT("rch not defined", procName, 1);
if (pindex) *pindex = rch->index;
if (pscore) *pscore = rch->score;
if (ptext) *ptext = stringNew(rch->text); /* new string: owned by caller */
if (psample) *psample = rch->sample;
if (pxloc) *pxloc = rch->xloc;
if (pyloc) *pyloc = rch->yloc;
if (pwidth) *pwidth = rch->width;
return 0;
}
/*!
* \brief transferRchToRcha()
*
* \param[in] rch source of data
* \param[in] rcha append to arrays in this destination
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This is used to transfer the results of a single character
* identification to an rcha array for the array of characters.
*
*/
static l_int32
transferRchToRcha(L_RCH *rch,
L_RCHA *rcha)
{
PROCNAME("transferRchToRcha");
if (!rch)
return ERROR_INT("rch not defined", procName, 1);
if (!rcha)
return ERROR_INT("rcha not defined", procName, 1);
numaAddNumber(rcha->naindex, rch->index);
numaAddNumber(rcha->nascore, rch->score);
sarrayAddString(rcha->satext, rch->text, L_COPY);
numaAddNumber(rcha->nasample, rch->sample);
numaAddNumber(rcha->naxloc, rch->xloc);
numaAddNumber(rcha->nayloc, rch->yloc);
numaAddNumber(rcha->nawidth, rch->width);
return 0;
}
/*------------------------------------------------------------------------*
* Preprocessing and filtering *
*------------------------------------------------------------------------*/
/*!
* \brief recogProcessToIdentify()
*
* \param[in] recog with LUT's pre-computed
* \param[in] pixs typ. single character, possibly d > 1 and uncropped
* \param[in] pad extra pixels added to left and right sides
* \return pixd 1 bpp, clipped to foreground, or NULL if there
* are no fg pixels or on error.
*
*
* Notes:
* (1) This is a lightweight operation to insure that the input
* image is 1 bpp, properly cropped, and padded on each side.
* If bpp > 1, the image is thresholded.
*
*/
PIX *
recogProcessToIdentify(L_RECOG *recog,
PIX *pixs,
l_int32 pad)
{
l_int32 canclip;
PIX *pix1, *pix2, *pixd;
PROCNAME("recogProcessToIdentify");
if (!recog)
return (PIX *)ERROR_PTR("recog not defined", procName, NULL);
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (pixGetDepth(pixs) != 1)
pix1 = pixThresholdToBinary(pixs, recog->threshold);
else
pix1 = pixClone(pixs);
pixTestClipToForeground(pix1, &canclip);
if (canclip)
pixClipToForeground(pix1, &pix2, NULL);
else
pix2 = pixClone(pix1);
pixDestroy(&pix1);
if (!pix2)
return (PIX *)ERROR_PTR("no foreground pixels", procName, NULL);
pixd = pixAddBorderGeneral(pix2, pad, pad, 0, 0, 0);
pixDestroy(&pix2);
return pixd;
}
/*!
* \brief recogPreSplittingFilter()
*
* \param[in] recog
* \param[in] pixs 1 bpp, many connected components
* \param[in] minh minimum height of components to be retained
* \param[in] minaf minimum area fraction (|fg|/(w*h)) to be retained
* \param[in] debug 1 to output indicator arrays
* \return pixd with filtered components removed or NULL on error
*/
static PIX *
recogPreSplittingFilter(L_RECOG *recog,
PIX *pixs,
l_int32 minh,
l_float32 minaf,
l_int32 debug)
{
l_int32 scaling, minsplitw, maxsplith, maxasp;
BOXA *boxas;
NUMA *naw, *nah, *na1, *na1c, *na2, *na3, *na4, *na5, *na6, *na7;
PIX *pixd;
PIXA *pixas;
PROCNAME("recogPreSplittingFilter");
if (!recog)
return (PIX *)ERROR_PTR("recog not defined", procName, NULL);
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
/* If there is scaling, do not remove components based on the
* values of min_splitw and max_splith. */
scaling = (recog->scalew > 0 || recog->scaleh > 0) ? TRUE : FALSE;
minsplitw = (scaling) ? 1 : recog->min_splitw - 3;
maxsplith = (scaling) ? 150 : recog->max_splith;
maxasp = recog->max_wh_ratio;
/* Generate an indicator array of connected components to remove:
* short stuff
* tall stuff
* components with large width/height ratio
* components with small area fill fraction */
boxas = pixConnComp(pixs, &pixas, 8);
pixaFindDimensions(pixas, &naw, &nah);
na1 = numaMakeThresholdIndicator(naw, minsplitw, L_SELECT_IF_LT);
na1c = numaCopy(na1);
na2 = numaMakeThresholdIndicator(nah, minh, L_SELECT_IF_LT);
na3 = numaMakeThresholdIndicator(nah, maxsplith, L_SELECT_IF_GT);
na4 = pixaFindWidthHeightRatio(pixas);
na5 = numaMakeThresholdIndicator(na4, maxasp, L_SELECT_IF_GT);
na6 = pixaFindAreaFraction(pixas);
na7 = numaMakeThresholdIndicator(na6, minaf, L_SELECT_IF_LT);
numaLogicalOp(na1, na1, na2, L_UNION);
numaLogicalOp(na1, na1, na3, L_UNION);
numaLogicalOp(na1, na1, na5, L_UNION);
numaLogicalOp(na1, na1, na7, L_UNION);
pixd = pixCopy(NULL, pixs);
pixRemoveWithIndicator(pixd, pixas, na1);
if (debug)
l_showIndicatorSplitValues(na1c, na2, na3, na5, na7, na1);
numaDestroy(&naw);
numaDestroy(&nah);
numaDestroy(&na1);
numaDestroy(&na1c);
numaDestroy(&na2);
numaDestroy(&na3);
numaDestroy(&na4);
numaDestroy(&na5);
numaDestroy(&na6);
numaDestroy(&na7);
boxaDestroy(&boxas);
pixaDestroy(&pixas);
return pixd;
}
/*!
* \brief recogSplittingFilter()
*
* \param[in] recog
* \param[in] pixs 1 bpp, single connected component
* \param[in] minh minimum height of component; 0 for default
* \param[in] minaf minimum area fraction (|fg|/(w*h)) to be retained
* \param[out] premove 0 to save, 1 to remove
* \param[in] debug 1 to output indicator arrays
* \return 0 if OK, 1 on error
*/
static l_int32
recogSplittingFilter(L_RECOG *recog,
PIX *pixs,
l_int32 minh,
l_float32 minaf,
l_int32 *premove,
l_int32 debug)
{
l_int32 w, h;
l_float32 aspratio, fract;
PROCNAME("recogSplittingFilter");
if (!premove)
return ERROR_INT("&remove not defined", procName, 1);
*premove = 0;
if (!recog)
return ERROR_INT("recog not defined", procName, 1);
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
if (minh <= 0) minh = DefaultMinHeight;
/* Remove from further consideration:
* small stuff
* components with large width/height ratio
* components with small area fill fraction */
pixGetDimensions(pixs, &w, &h, NULL);
if (w < recog->min_splitw) {
if (debug) L_INFO("w = %d < %d\n", procName, w, recog->min_splitw);
*premove = 1;
return 0;
}
if (h < minh) {
if (debug) L_INFO("h = %d < %d\n", procName, h, minh);
*premove = 1;
return 0;
}
aspratio = (l_float32)w / (l_float32)h;
if (aspratio > recog->max_wh_ratio) {
if (debug) L_INFO("w/h = %5.3f too large\n", procName, aspratio);
*premove = 1;
return 0;
}
pixFindAreaFraction(pixs, recog->sumtab, &fract);
if (fract < minaf) {
if (debug) L_INFO("area fill fract %5.3f < %5.3f\n",
procName, fract, minaf);
*premove = 1;
return 0;
}
return 0;
}
/*------------------------------------------------------------------------*
* Postprocessing *
*------------------------------------------------------------------------*/
/*!
* \brief recogExtractNumbers()
*
* \param[in] recog
* \param[in] boxas location of components
* \param[in] scorethresh min score for which we accept a component
* \param[in] spacethresh max horizontal distance allowed between digits;
* use -1 for default
* \param[out] pbaa [optional] bounding boxes of identified numbers
* \param[out] pnaa [optional] scores of identified digits
* \return sa of identified numbers, or NULL on error
*
*
* Notes:
* (1) This extracts digit data after recogaIdentifyMultiple() or
* lower-level identification has taken place.
* (2) Each string in the returned sa contains a sequence of ascii
* digits in a number.
* (3) The horizontal distance between boxes (limited by %spacethresh)
* is the negative of the horizontal overlap.
* (4) Components with a score less than %scorethresh, which may
* be hyphens or other small characters, will signal the
* end of the current sequence of digits in the number. A typical
* value for %scorethresh is 0.60.
* (5) We allow two digits to be combined if these conditions apply:
* (a) the first is to the left of the second
* (b) the second has a horizontal separation less than %spacethresh
* (c) the vertical overlap >= 0 (vertical separation < 0)
* (d) both have a score that exceeds %scorethresh
* (6) Each numa in the optionally returned naa contains the digit
* scores of a number. Each boxa in the optionally returned baa
* contains the bounding boxes of the digits in the number.
*
*/
SARRAY *
recogExtractNumbers(L_RECOG *recog,
BOXA *boxas,
l_float32 scorethresh,
l_int32 spacethresh,
BOXAA **pbaa,
NUMAA **pnaa)
{
char *str, *text;
l_int32 i, n, x1, x2, h_ovl, v_ovl, h_sep, v_sep;
l_float32 score;
BOX *box, *prebox;
BOXA *ba;
BOXAA *baa;
NUMA *nascore, *na;
NUMAA *naa;
SARRAY *satext, *sa, *saout;
PROCNAME("recogExtractNumbers");
if (pbaa) *pbaa = NULL;
if (pnaa) *pnaa = NULL;
if (!recog || !recog->rcha)
return (SARRAY *)ERROR_PTR("recog and rcha not both defined",
procName, NULL);
if (!boxas)
return (SARRAY *)ERROR_PTR("boxas not defined", procName, NULL);
if (spacethresh < 0)
spacethresh = L_MAX(recog->maxheight_u, 20);
rchaExtract(recog->rcha, NULL, &nascore, &satext, NULL, NULL, NULL, NULL);
if (!nascore || !satext) {
numaDestroy(&nascore);
sarrayDestroy(&satext);
return (SARRAY *)ERROR_PTR("nascore and satext not both returned",
procName, NULL);
}
saout = sarrayCreate(0);
naa = numaaCreate(0);
baa = boxaaCreate(0);
prebox = NULL;
n = numaGetCount(nascore);
for (i = 0; i < n; i++) {
numaGetFValue(nascore, i, &score);
text = sarrayGetString(satext, i, L_NOCOPY);
if (prebox == NULL) { /* no current run */
if (score < scorethresh) {
continue;
} else { /* start a number run */
sa = sarrayCreate(0);
ba = boxaCreate(0);
na = numaCreate(0);
sarrayAddString(sa, text, L_COPY);
prebox = boxaGetBox(boxas, i, L_CLONE);
boxaAddBox(ba, prebox, L_COPY);
numaAddNumber(na, score);
}
} else { /* in a current number run */
box = boxaGetBox(boxas, i, L_CLONE);
boxGetGeometry(prebox, &x1, NULL, NULL, NULL);
boxGetGeometry(box, &x2, NULL, NULL, NULL);
boxOverlapDistance(box, prebox, &h_ovl, &v_ovl);
h_sep = -h_ovl;
v_sep = -v_ovl;
boxDestroy(&prebox);
if (x1 < x2 && h_sep <= spacethresh &&
v_sep < 0 && score >= scorethresh) { /* add to number */
sarrayAddString(sa, text, L_COPY);
boxaAddBox(ba, box, L_COPY);
numaAddNumber(na, score);
prebox = box;
} else { /* save the completed number */
str = sarrayToString(sa, 0);
sarrayAddString(saout, str, L_INSERT);
sarrayDestroy(&sa);
boxaaAddBoxa(baa, ba, L_INSERT);
numaaAddNuma(naa, na, L_INSERT);
boxDestroy(&box);
if (score >= scorethresh) { /* start a new number */
i--;
continue;
}
}
}
}
if (prebox) { /* save the last number */
str = sarrayToString(sa, 0);
sarrayAddString(saout, str, L_INSERT);
boxaaAddBoxa(baa, ba, L_INSERT);
numaaAddNuma(naa, na, L_INSERT);
sarrayDestroy(&sa);
boxDestroy(&prebox);
}
numaDestroy(&nascore);
sarrayDestroy(&satext);
if (sarrayGetCount(saout) == 0) {
sarrayDestroy(&saout);
boxaaDestroy(&baa);
numaaDestroy(&naa);
L_INFO("saout has no identified text\n", procName);
return NULL;
}
if (pbaa)
*pbaa = baa;
else
boxaaDestroy(&baa);
if (pnaa)
*pnaa = naa;
else
numaaDestroy(&naa);
return saout;
}
/*!
* \brief showExtractNumbers()
*
* \param[in] pixs input 1 bpp image
* \param[in] sa recognized text strings
* \param[in] baa boxa array for location of characters in each string
* \param[in] naa numa array for scores of characters in each string
* \param[out] ppixdb [optional] input pixs with identified chars outlined
* \return pixa of identified strings with text and scores, or NULL on error
*
*
* Notes:
* (1) This is a debugging routine on digit identification; e.g.:
* recogIdentifyMultiple(recog, pixs, 0, 1, &boxa, NULL, NULL, 0);
* sa = recogExtractNumbers(recog, boxa, 0.8, -1, &baa, &naa);
* pixa = showExtractNumbers(pixs, sa, baa, naa, NULL);
*
*/
PIXA *
showExtractNumbers(PIX *pixs,
SARRAY *sa,
BOXAA *baa,
NUMAA *naa,
PIX **ppixdb)
{
char buf[128];
char *textstr, *scorestr;
l_int32 i, j, n, nchar, len;
l_float32 score;
L_BMF *bmf;
BOX *box1, *box2;
BOXA *ba;
NUMA *na;
PIX *pix1, *pix2, *pix3, *pix4;
PIXA *pixa;
PROCNAME("showExtractNumbers");
if (ppixdb) *ppixdb = NULL;
if (!pixs)
return (PIXA *)ERROR_PTR("pixs not defined", procName, NULL);
if (!sa)
return (PIXA *)ERROR_PTR("sa not defined", procName, NULL);
if (!baa)
return (PIXA *)ERROR_PTR("baa not defined", procName, NULL);
if (!naa)
return (PIXA *)ERROR_PTR("naa not defined", procName, NULL);
n = sarrayGetCount(sa);
pixa = pixaCreate(n);
bmf = bmfCreate(NULL, 6);
if (ppixdb) *ppixdb = pixConvertTo8(pixs, 1);
for (i = 0; i < n; i++) {
textstr = sarrayGetString(sa, i, L_NOCOPY);
ba = boxaaGetBoxa(baa, i, L_CLONE);
na = numaaGetNuma(naa, i, L_CLONE);
boxaGetExtent(ba, NULL, NULL, &box1);
box2 = boxAdjustSides(NULL, box1, -5, 5, -5, 5);
if (ppixdb) pixRenderBoxArb(*ppixdb, box2, 3, 255, 0, 0);
pix1 = pixClipRectangle(pixs, box1, NULL);
len = strlen(textstr) + 1;
pix2 = pixAddBlackOrWhiteBorder(pix1, 14 * len, 14 * len,
5, 3, L_SET_WHITE);
pix3 = pixConvertTo8(pix2, 1);
nchar = numaGetCount(na);
scorestr = NULL;
for (j = 0; j < nchar; j++) {
numaGetFValue(na, j, &score);
snprintf(buf, sizeof(buf), "%d", (l_int32)(100 * score));
stringJoinIP(&scorestr, buf);
if (j < nchar - 1) stringJoinIP(&scorestr, ",");
}
snprintf(buf, sizeof(buf), "%s: %s\n", textstr, scorestr);
pix4 = pixAddTextlines(pix3, bmf, buf, 0xff000000, L_ADD_BELOW);
pixaAddPix(pixa, pix4, L_INSERT);
boxDestroy(&box1);
boxDestroy(&box2);
pixDestroy(&pix1);
pixDestroy(&pix2);
pixDestroy(&pix3);
boxaDestroy(&ba);
numaDestroy(&na);
LEPT_FREE(scorestr);
}
bmfDestroy(&bmf);
return pixa;
}
/*------------------------------------------------------------------------*
* Static debug helper *
*------------------------------------------------------------------------*/
/*!
* \brief l_showIndicatorSplitValues()
*
* \param[in] na1, na2, na3, na4, na5, na6 6 indicator array
*
*
* Notes:
* (1) The values indicate that specific criteria has been met
* for component removal by pre-splitting filter..
* The 'result' line shows which components have been removed.
*
*/
static void
l_showIndicatorSplitValues(NUMA *na1,
NUMA *na2,
NUMA *na3,
NUMA *na4,
NUMA *na5,
NUMA *na6)
{
l_int32 i, n;
n = numaGetCount(na1);
lept_stderr("================================================\n");
lept_stderr("lt minw: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na1->array[i]);
lept_stderr("\nlt minh: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na2->array[i]);
lept_stderr("\ngt maxh: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na3->array[i]);
lept_stderr("\ngt maxasp: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na4->array[i]);
lept_stderr("\nlt minaf: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na5->array[i]);
lept_stderr("\n------------------------------------------------");
lept_stderr("\nresult: ");
for (i = 0; i < n; i++)
lept_stderr("%4d ", (l_int32)na6->array[i]);
lept_stderr("\n================================================\n");
}