#endif /* HAVE_CONFIG_H */
#include "allheaders.h"
static l_int32 boxHasOverlapInXorY(l_int32 c1, l_int32 s1, l_int32 c2,
l_int32 s2);
static l_int32 boxGetDistanceInXorY(l_int32 c1, l_int32 s1, l_int32 c2,
l_int32 s2);
/*---------------------------------------------------------------------*
* Box geometry *
*---------------------------------------------------------------------*/
/*!
* \brief boxContains()
*
* \param[in] box1, box2
* \param[out] presult 1 if box2 is entirely contained within box1;
* 0 otherwise
* \return 0 if OK, 1 on error
*/
l_ok
boxContains(BOX *box1,
BOX *box2,
l_int32 *presult)
{
l_int32 x1, y1, w1, h1, x2, y2, w2, h2, valid1, valid2;
PROCNAME("boxContains");
if (!presult)
return ERROR_INT("&result not defined", procName, 1);
*presult = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
boxGetGeometry(box1, &x1, &y1, &w1, &h1);
boxGetGeometry(box2, &x2, &y2, &w2, &h2);
if (x1 <= x2 && y1 <= y2 && (x1 + w1 >= x2 + w2) && (y1 + h1 >= y2 + h2))
*presult = 1;
return 0;
}
/*!
* \brief boxIntersects()
*
* \param[in] box1, box2
* \param[out] presult 1 if any part of box2 is contained in box1;
* 0 otherwise
* \return 0 if OK, 1 on error
*/
l_ok
boxIntersects(BOX *box1,
BOX *box2,
l_int32 *presult)
{
l_int32 l1, l2, r1, r2, t1, t2, b1, b2, w1, h1, w2, h2, valid1, valid2;
PROCNAME("boxIntersects");
if (!presult)
return ERROR_INT("&result not defined", procName, 1);
*presult = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
boxGetGeometry(box1, &l1, &t1, &w1, &h1);
boxGetGeometry(box2, &l2, &t2, &w2, &h2);
r1 = l1 + w1 - 1;
r2 = l2 + w2 - 1;
b1 = t1 + h1 - 1;
b2 = t2 + h2 - 1;
if (b2 < t1 || b1 < t2 || r1 < l2 || r2 < l1)
*presult = 0;
else
*presult = 1;
return 0;
}
/*!
* \brief boxaContainedInBox()
*
* \param[in] boxas
* \param[in] box for containment
* \return boxad boxa with all boxes in boxas that are entirely
* contained in box, or NULL on error
*
*
* Notes:
* (1) All boxes in %boxas that are entirely outside box are removed.
* (2) If %box is not valid, returns an empty boxa.
*
*/
BOXA *
boxaContainedInBox(BOXA *boxas,
BOX *box)
{
l_int32 i, n, val, valid;
BOX *box1;
BOXA *boxad;
PROCNAME("boxaContainedInBox");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (!box)
return (BOXA *)ERROR_PTR("box not defined", procName, NULL);
n = boxaGetCount(boxas);
boxIsValid(box, &valid);
if (n == 0 || !valid)
return boxaCreate(1); /* empty */
boxad = boxaCreate(0);
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxas, i, L_CLONE)) == NULL)
continue;
boxContains(box, box1, &val);
if (val == 1)
boxaAddBox(boxad, box1, L_COPY);
boxDestroy(&box1); /* destroy the clone */
}
return boxad;
}
/*!
* \brief boxaContainedInBoxCount()
*
* \param[in] boxa
* \param[in] box for selecting contained boxes in %boxa
* \param[out] pcount number of boxes intersecting the box
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) If %box is not valid, returns a zero count.
*
*/
l_ok
boxaContainedInBoxCount(BOXA *boxa,
BOX *box,
l_int32 *pcount)
{
l_int32 i, n, val, valid;
BOX *box1;
PROCNAME("boxaContainedInBoxCount");
if (!pcount)
return ERROR_INT("&count not defined", procName, 1);
*pcount = 0;
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
if (!box)
return ERROR_INT("box not defined", procName, 1);
n = boxaGetCount(boxa);
boxIsValid(box, &valid);
if (n == 0 || !valid)
return 0;
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxa, i, L_CLONE)) == NULL)
continue;
boxContains(box, box1, &val);
if (val == 1)
(*pcount)++;
boxDestroy(&box1);
}
return 0;
}
/*!
* \brief boxaContainedInBoxa()
*
* \param[in] boxa1, boxa2
* \param[out] pcontained 1 if every box in boxa2 is contained in
* some box in boxa1; 0 otherwise
* \return 0 if OK, 1 on error
*/
l_ok
boxaContainedInBoxa(BOXA *boxa1,
BOXA *boxa2,
l_int32 *pcontained)
{
l_int32 i, j, n1, n2, cont, result;
BOX *box1, *box2;
PROCNAME("boxaContainedInBoxa");
if (!pcontained)
return ERROR_INT("&contained not defined", procName, 1);
*pcontained = 0;
if (!boxa1 || !boxa2)
return ERROR_INT("boxa1 and boxa2 not both defined", procName, 1);
n1 = boxaGetCount(boxa1);
n2 = boxaGetCount(boxa2);
for (i = 0; i < n2; i++) {
if ((box2 = boxaGetValidBox(boxa2, i, L_CLONE)) == NULL)
continue;
cont = 0;
for (j = 0; j < n1; j++) {
if ((box1 = boxaGetValidBox(boxa1, j, L_CLONE)) == NULL)
continue;
boxContains(box1, box2, &result);
boxDestroy(&box1);
if (result) {
cont = 1;
break;
}
}
boxDestroy(&box2);
if (!cont) return 0;
}
*pcontained = 1;
return 0;
}
/*!
* \brief boxaIntersectsBox()
*
* \param[in] boxas
* \param[in] box for intersecting
* \return boxad boxa with all boxes in boxas that intersect box,
* or NULL on error
*
*
* Notes:
* (1) All boxes in boxa that intersect with box (i.e., are completely
* or partially contained in box) are retained.
*
*/
BOXA *
boxaIntersectsBox(BOXA *boxas,
BOX *box)
{
l_int32 i, n, val, valid;
BOX *box1;
BOXA *boxad;
PROCNAME("boxaIntersectsBox");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (!box)
return (BOXA *)ERROR_PTR("box not defined", procName, NULL);
n = boxaGetCount(boxas);
boxIsValid(box, &valid);
if (n == 0 || !valid)
return boxaCreate(1); /* empty */
boxad = boxaCreate(0);
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxas, i, L_CLONE)) == NULL)
continue;
boxIntersects(box, box1, &val);
if (val == 1)
boxaAddBox(boxad, box1, L_COPY);
boxDestroy(&box1); /* destroy the clone */
}
return boxad;
}
/*!
* \brief boxaIntersectsBoxCount()
*
* \param[in] boxa
* \param[in] box for selecting intersecting boxes in %boxa
* \param[out] pcount number of boxes intersecting the box
* \return 0 if OK, 1 on error
*/
l_ok
boxaIntersectsBoxCount(BOXA *boxa,
BOX *box,
l_int32 *pcount)
{
l_int32 i, n, val, valid;
BOX *box1;
PROCNAME("boxaIntersectsBoxCount");
if (!pcount)
return ERROR_INT("&count not defined", procName, 1);
*pcount = 0;
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
if (!box)
return ERROR_INT("box not defined", procName, 1);
n = boxaGetCount(boxa);
boxIsValid(box, &valid);
if (n == 0 || !valid)
return 0;
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxa, i, L_CLONE)) == NULL)
continue;
boxIntersects(box, box1, &val);
if (val == 1)
(*pcount)++;
boxDestroy(&box1);
}
return 0;
}
/*!
* \brief boxaClipToBox()
*
* \param[in] boxas
* \param[in] box for clipping
* \return boxad boxa with boxes in boxas clipped to box, or NULL on error
*
*
* Notes:
* (1) All boxes in boxa not intersecting with box are removed, and
* the remaining boxes are clipped to box.
*
*/
BOXA *
boxaClipToBox(BOXA *boxas,
BOX *box)
{
l_int32 i, n, valid;
BOX *box1, *boxo;
BOXA *boxad;
PROCNAME("boxaClipToBox");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (!box)
return (BOXA *)ERROR_PTR("box not defined", procName, NULL);
n = boxaGetCount(boxas);
boxIsValid(box, &valid);
if (n == 0 || !valid)
return boxaCreate(1); /* empty */
boxad = boxaCreate(0);
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxas, i, L_CLONE)) == NULL)
continue;
if ((boxo = boxOverlapRegion(box, box1)) != NULL)
boxaAddBox(boxad, boxo, L_INSERT);
boxDestroy(&box1);
}
return boxad;
}
/*!
* \brief boxaCombineOverlaps()
*
* \param[in] boxas
* \param[in,out] pixadb debug output
* \return boxad where each set of boxes in boxas that overlap are combined
* into a single bounding box in boxad, or NULL on error.
*
*
* Notes:
* (1) If there are no overlapping boxes, it simply returns a copy
* of %boxas.
* (2) Input an empty %pixadb, using pixaCreate(0), for debug output.
* The output gives 2 visualizations of the boxes per iteration;
* boxes in red before, and added boxes in green after. Note that
* all pixels in the red boxes are contained in the green ones.
* (3) The alternative method of painting each rectangle and finding
* the 4-connected components gives a different result in
* general, because two non-overlapping (but touching)
* rectangles, when rendered, are 4-connected and will be joined.
* (4) A bad case computationally is to have n boxes, none of which
* overlap. Then you have one iteration with O(n^2) compares.
* This is still faster than painting each rectangle and finding
* the bounding boxes of the connected components, even for
* thousands of rectangles.
*
*/
BOXA *
boxaCombineOverlaps(BOXA *boxas,
PIXA *pixadb)
{
l_int32 i, j, w, h, n1, n2, overlap, niters;
BOX *box1, *box2, *box3;
BOXA *boxa1, *boxa2;
PIX *pix1;
PROCNAME("boxaCombineOverlaps");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (pixadb) boxaGetExtent(boxas, &w, &h, NULL);
boxa1 = boxaCopy(boxas, L_COPY);
n1 = boxaGetCount(boxa1);
niters = 0;
while (1) { /* loop until no change from previous iteration */
niters++;
if (pixadb) {
pix1 = pixCreate(w + 5, h + 5, 32);
pixSetAll(pix1);
pixRenderBoxaArb(pix1, boxa1, 2, 255, 0, 0);
pixaAddPix(pixadb, pix1, L_COPY);
}
/* Combine overlaps for this iteration */
for (i = 0; i < n1; i++) {
if ((box1 = boxaGetValidBox(boxa1, i, L_COPY)) == NULL)
continue;
for (j = i + 1; j < n1; j++) {
if ((box2 = boxaGetValidBox(boxa1, j, L_COPY)) == NULL)
continue;
boxIntersects(box1, box2, &overlap);
if (overlap) {
box3 = boxBoundingRegion(box1, box2);
boxaReplaceBox(boxa1, i, box3);
boxaReplaceBox(boxa1, j, boxCreate(0, 0, 0, 0));
boxDestroy(&box1);
box1 = boxCopy(box3);
}
boxDestroy(&box2);
}
boxDestroy(&box1);
}
boxa2 = boxaSaveValid(boxa1, L_COPY);
n2 = boxaGetCount(boxa2);
boxaDestroy(&boxa1);
boxa1 = boxa2;
if (n1 == n2) {
if (pixadb) pixDestroy(&pix1);
break;
}
n1 = n2;
if (pixadb) {
pixRenderBoxaArb(pix1, boxa1, 2, 0, 255, 0);
pixaAddPix(pixadb, pix1, L_INSERT);
}
}
if (pixadb)
L_INFO("number of iterations: %d\n", procName, niters);
return boxa1;
}
/*!
* \brief boxaCombineOverlapsInPair()
*
* \param[in] boxas1 input boxa1
* \param[in] boxas2 input boxa2
* \param[out] pboxad1 output boxa1
* \param[out] pboxad2 output boxa2
* \param[in,out] pixadb debug output
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) One of three things happens to each box in %boxa1 and %boxa2:
* * it gets absorbed into a larger box that it overlaps with
* * it absorbs a smaller (by area) box that it overlaps with
* and gets larger, using the bounding region of the 2 boxes
* * it is unchanged (including absorbing smaller boxes that
* are contained within it).
* (2) If all the boxes from one of the input boxa are absorbed, this
* returns an empty boxa.
* (3) Input an empty %pixadb, using pixaCreate(0), for debug output
* (4) This is useful if different operations are to be carried out
* on possibly overlapping rectangular regions, and it is desired
* to have only one operation on any rectangular region.
*
*/
l_ok
boxaCombineOverlapsInPair(BOXA *boxas1,
BOXA *boxas2,
BOXA **pboxad1,
BOXA **pboxad2,
PIXA *pixadb)
{
l_int32 i, j, w, h, w2, h2, n1, n2, n1i, n2i, niters;
l_int32 overlap, bigger, area1, area2;
BOX *box1, *box2, *box3;
BOXA *boxa1, *boxa2, *boxac1, *boxac2;
PIX *pix1;
PROCNAME("boxaCombineOverlapsInPair");
if (pboxad1) *pboxad1 = NULL;
if (pboxad2) *pboxad2 = NULL;
if (!boxas1 || !boxas2)
return ERROR_INT("boxas1 and boxas2 not both defined", procName, 1);
if (!pboxad1 || !pboxad2)
return ERROR_INT("&boxad1 and &boxad2 not both defined", procName, 1);
if (pixadb) {
boxaGetExtent(boxas1, &w, &h, NULL);
boxaGetExtent(boxas2, &w2, &h2, NULL);
w = L_MAX(w, w2);
h = L_MAX(h, w2);
}
/* Let the boxa with the largest area have first crack at the other */
boxaGetArea(boxas1, &area1);
boxaGetArea(boxas2, &area2);
if (area1 >= area2) {
boxac1 = boxaCopy(boxas1, L_COPY);
boxac2 = boxaCopy(boxas2, L_COPY);
} else {
boxac1 = boxaCopy(boxas2, L_COPY);
boxac2 = boxaCopy(boxas1, L_COPY);
}
n1i = boxaGetCount(boxac1);
n2i = boxaGetCount(boxac2);
niters = 0;
while (1) {
niters++;
if (pixadb) {
pix1 = pixCreate(w + 5, h + 5, 32);
pixSetAll(pix1);
pixRenderBoxaArb(pix1, boxac1, 2, 255, 0, 0);
pixRenderBoxaArb(pix1, boxac2, 2, 0, 255, 0);
pixaAddPix(pixadb, pix1, L_INSERT);
}
/* First combine boxes in each set */
boxa1 = boxaCombineOverlaps(boxac1, NULL);
boxa2 = boxaCombineOverlaps(boxac2, NULL);
/* Now combine boxes between sets */
n1 = boxaGetCount(boxa1);
n2 = boxaGetCount(boxa2);
for (i = 0; i < n1; i++) { /* 1 eats 2 */
if ((box1 = boxaGetValidBox(boxa1, i, L_COPY)) == NULL)
continue;
for (j = 0; j < n2; j++) {
if ((box2 = boxaGetValidBox(boxa2, j, L_COPY)) == NULL)
continue;
boxIntersects(box1, box2, &overlap);
boxCompareSize(box1, box2, L_SORT_BY_AREA, &bigger);
if (overlap && (bigger == 1)) {
box3 = boxBoundingRegion(box1, box2);
boxaReplaceBox(boxa1, i, box3);
boxaReplaceBox(boxa2, j, boxCreate(0, 0, 0, 0));
boxDestroy(&box1);
box1 = boxCopy(box3);
}
boxDestroy(&box2);
}
boxDestroy(&box1);
}
for (i = 0; i < n2; i++) { /* 2 eats 1 */
if ((box2 = boxaGetValidBox(boxa2, i, L_COPY)) == NULL)
continue;
for (j = 0; j < n1; j++) {
if ((box1 = boxaGetValidBox(boxa1, j, L_COPY)) == NULL)
continue;
boxIntersects(box1, box2, &overlap);
boxCompareSize(box2, box1, L_SORT_BY_AREA, &bigger);
if (overlap && (bigger == 1)) {
box3 = boxBoundingRegion(box1, box2);
boxaReplaceBox(boxa2, i, box3);
boxaReplaceBox(boxa1, j, boxCreate(0, 0, 0, 0));
boxDestroy(&box2);
box2 = boxCopy(box3);
}
boxDestroy(&box1);
}
boxDestroy(&box2);
}
boxaDestroy(&boxac1);
boxaDestroy(&boxac2);
boxac1 = boxaSaveValid(boxa1, L_COPY); /* remove invalid boxes */
boxac2 = boxaSaveValid(boxa2, L_COPY);
boxaDestroy(&boxa1);
boxaDestroy(&boxa2);
n1 = boxaGetCount(boxac1);
n2 = boxaGetCount(boxac2);
if (n1 == n1i && n2 == n2i) break;
n1i = n1;
n2i = n2;
if (pixadb) {
pix1 = pixCreate(w + 5, h + 5, 32);
pixSetAll(pix1);
pixRenderBoxaArb(pix1, boxac1, 2, 255, 0, 0);
pixRenderBoxaArb(pix1, boxac2, 2, 0, 255, 0);
pixaAddPix(pixadb, pix1, L_INSERT);
}
}
if (pixadb)
L_INFO("number of iterations: %d\n", procName, niters);
*pboxad1 = boxac1;
*pboxad2 = boxac2;
return 0;
}
/*!
* \brief boxOverlapRegion()
*
* \param[in] box1, box2
* \return box of overlap region between input boxes;
* NULL if no overlap or on error
*
*
* Notes:
* (1) This is the geometric intersection of the two rectangles.
*
*/
BOX *
boxOverlapRegion(BOX *box1,
BOX *box2)
{
l_int32 l1, l2, r1, r2, t1, t2, b1, b2, w1, h1, w2, h2, ld, td, rd, bd;
l_int32 valid1, valid2;
PROCNAME("boxOverlapRegion");
if (!box1 || !box2)
return (BOX *)ERROR_PTR("boxes not both defined", procName, NULL);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2) {
L_WARNING("at least one box is invalid\n", procName);
return NULL;
}
boxGetGeometry(box1, &l1, &t1, &w1, &h1);
boxGetGeometry(box2, &l2, &t2, &w2, &h2);
r1 = l1 + w1 - 1;
r2 = l2 + w2 - 1;
b1 = t1 + h1 - 1;
b2 = t2 + h2 - 1;
if (b2 < t1 || b1 < t2 || r1 < l2 || r2 < l1)
return NULL;
ld = L_MAX(l1, l2);
td = L_MAX(t1, t2);
rd = L_MIN(r1, r2);
bd = L_MIN(b1, b2);
return boxCreate(ld, td, rd - ld + 1, bd - td + 1);
}
/*!
* \brief boxBoundingRegion()
*
* \param[in] box1, box2
* \return box of bounding region containing the input boxes;
* NULL on error
*
*
* Notes:
* (1) This is the geometric union of the two rectangles.
* (2) Invalid boxes are ignored. This returns an invalid box
* if both input boxes are invalid.
* (3) For the geometric union of a boxa, use boxaGetExtent().
*
*/
BOX *
boxBoundingRegion(BOX *box1,
BOX *box2)
{
l_int32 l1, l2, r1, r2, t1, t2, b1, b2, w1, h1, w2, h2, ld, td, rd, bd;
l_int32 valid1, valid2;
PROCNAME("boxBoundingRegion");
if (!box1 || !box2)
return (BOX *)ERROR_PTR("boxes not both defined", procName, NULL);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 && !valid2) {
L_WARNING("both boxes are invalid\n", procName);
return boxCreate(0, 0, 0, 0);
}
if (valid1 && !valid2)
return boxCopy(box1);
if (!valid1 && valid2)
return boxCopy(box2);
boxGetGeometry(box1, &l1, &t1, &w1, &h1);
boxGetGeometry(box2, &l2, &t2, &w2, &h2);
r1 = l1 + w1 - 1;
r2 = l2 + w2 - 1;
b1 = t1 + h1 - 1;
b2 = t2 + h2 - 1;
ld = L_MIN(l1, l2);
td = L_MIN(t1, t2);
rd = L_MAX(r1, r2);
bd = L_MAX(b1, b2);
return boxCreate(ld, td, rd - ld + 1, bd - td + 1);
}
/*!
* \brief boxOverlapFraction()
*
* \param[in] box1, box2
* \param[out] pfract the fraction of box2 overlapped by box1
* \return 0 if OK, 1 on error.
*
*
* Notes:
* (1) The result depends on the order of the input boxes,
* because the overlap is taken as a fraction of box2.
* (2) If at least one box is not valid, there is no overlap.
*
*/
l_ok
boxOverlapFraction(BOX *box1,
BOX *box2,
l_float32 *pfract)
{
l_int32 w2, h2, w, h, valid1, valid2;
BOX *boxo;
PROCNAME("boxOverlapFraction");
if (!pfract)
return ERROR_INT("&fract not defined", procName, 1);
*pfract = 0.0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2) {
L_WARNING("boxes not both valid\n", procName);
return 0;
}
if ((boxo = boxOverlapRegion(box1, box2)) == NULL) /* no overlap */
return 0;
boxGetGeometry(box2, NULL, NULL, &w2, &h2);
boxGetGeometry(boxo, NULL, NULL, &w, &h);
*pfract = (l_float32)(w * h) / (l_float32)(w2 * h2);
boxDestroy(&boxo);
return 0;
}
/*!
* \brief boxOverlapArea()
*
* \param[in] box1, box2
* \param[out] parea the number of pixels in the overlap
* \return 0 if OK, 1 on error.
*/
l_ok
boxOverlapArea(BOX *box1,
BOX *box2,
l_int32 *parea)
{
l_int32 w, h, valid1, valid2;
BOX *box;
PROCNAME("boxOverlapArea");
if (!parea)
return ERROR_INT("&area not defined", procName, 1);
*parea = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
if ((box = boxOverlapRegion(box1, box2)) == NULL) /* no overlap */
return 0;
boxGetGeometry(box, NULL, NULL, &w, &h);
*parea = w * h;
boxDestroy(&box);
return 0;
}
/*!
* \brief boxaHandleOverlaps()
*
* \param[in] boxas
* \param[in] op L_COMBINE, L_REMOVE_SMALL
* \param[in] range forward distance over which overlaps
* are checked; > 0
* \param[in] min_overlap minimum fraction of smaller box required for
* overlap to count; 0.0 to ignore
* \param[in] max_ratio maximum fraction of small/large areas for
* overlap to count; 1.0 to ignore
* \param[out] pnamap [optional] combining map
* \return boxad, or NULL on error.
*
*
* Notes:
* (1) For all n(n-1)/2 box pairings, if two boxes overlap, either:
* (a) op == L_COMBINE: get the bounding region for the two,
* replace the larger with the bounding region, and remove
* the smaller of the two, or
* (b) op == L_REMOVE_SMALL: just remove the smaller.
* (2) If boxas is 2D sorted, range can be small, but if it is
* not spatially sorted, range should be large to allow all
* pairwise comparisons to be made.
* (3) The %min_overlap parameter allows ignoring small overlaps.
* If %min_overlap == 1.0, only boxes fully contained in larger
* boxes can be considered for removal; if %min_overlap == 0.0,
* this constraint is ignored.
* (4) The %max_ratio parameter allows ignoring overlaps between
* boxes that are not too different in size. If %max_ratio == 0.0,
* no boxes can be removed; if %max_ratio == 1.0, this constraint
* is ignored.
*
*/
BOXA *
boxaHandleOverlaps(BOXA *boxas,
l_int32 op,
l_int32 range,
l_float32 min_overlap,
l_float32 max_ratio,
NUMA **pnamap)
{
l_int32 i, j, n, w, h, area1, area2, val;
l_int32 overlap_area;
l_float32 overlap_ratio, area_ratio;
BOX *box1, *box2, *box3;
BOXA *boxat, *boxad;
NUMA *namap;
PROCNAME("boxaHandleOverlaps");
if (pnamap) *pnamap = NULL;
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (op != L_COMBINE && op != L_REMOVE_SMALL)
return (BOXA *)ERROR_PTR("invalid op", procName, NULL);
n = boxaGetCount(boxas);
if (n == 0)
return boxaCreate(1); /* empty */
if (range == 0) {
L_WARNING("range is 0\n", procName);
return boxaCopy(boxas, L_COPY);
}
/* Identify smaller boxes in overlap pairs, and mark to eliminate. */
namap = numaMakeConstant(-1, n);
for (i = 0; i < n; i++) {
if ((box1 = boxaGetValidBox(boxas, i, L_CLONE)) == NULL)
continue;
boxGetGeometry(box1, NULL, NULL, &w, &h);
area1 = w * h;
if (area1 == 0) {
boxDestroy(&box1);
continue;
}
for (j = i + 1; j < i + 1 + range && j < n; j++) {
if ((box2 = boxaGetValidBox(boxas, j, L_CLONE)) == NULL)
continue;
boxOverlapArea(box1, box2, &overlap_area);
if (overlap_area > 0) {
boxGetGeometry(box2, NULL, NULL, &w, &h);
area2 = w * h;
if (area2 == 0) {
/* do nothing */
} else if (area1 >= area2) {
overlap_ratio = (l_float32)overlap_area / (l_float32)area2;
area_ratio = (l_float32)area2 / (l_float32)area1;
if (overlap_ratio >= min_overlap &&
area_ratio <= max_ratio) {
numaSetValue(namap, j, i);
}
} else {
overlap_ratio = (l_float32)overlap_area / (l_float32)area1;
area_ratio = (l_float32)area1 / (l_float32)area2;
if (overlap_ratio >= min_overlap &&
area_ratio <= max_ratio) {
numaSetValue(namap, i, j);
}
}
}
boxDestroy(&box2);
}
boxDestroy(&box1);
}
boxat = boxaCopy(boxas, L_COPY);
if (op == L_COMBINE) {
/* Resize the larger of the pair to the bounding region */
for (i = 0; i < n; i++) {
numaGetIValue(namap, i, &val);
if (val >= 0) {
box1 = boxaGetBox(boxas, i, L_CLONE); /* smaller */
box2 = boxaGetBox(boxas, val, L_CLONE); /* larger */
box3 = boxBoundingRegion(box1, box2);
boxaReplaceBox(boxat, val, box3);
boxDestroy(&box1);
boxDestroy(&box2);
}
}
}
/* Remove the smaller of the pairs */
boxad = boxaCreate(n);
for (i = 0; i < n; i++) {
numaGetIValue(namap, i, &val);
if (val == -1) {
box1 = boxaGetBox(boxat, i, L_COPY);
boxaAddBox(boxad, box1, L_INSERT);
}
}
boxaDestroy(&boxat);
if (pnamap)
*pnamap = namap;
else
numaDestroy(&namap);
return boxad;
}
/*!
* \brief boxOverlapDistance()
*
* \param[in] box1, box2 two boxes, in any order
* \param[out] ph_ovl [optional] horizontal overlap
* \param[out] pv_ovl [optional] vertical overlap
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This measures horizontal and vertical overlap of the
* two boxes. Horizontal and vertical overlap are measured
* independently. We need to consider several cases to clarify.
* (2) A positive horizontal overlap means that there is at least
* one point on the the %box1 boundary with the same x-component
* as some point on the %box2 boundary. Conversely, with a zero
* or negative horizontal overlap, there are no boundary pixels
* in %box1 that share an x-component with a boundary pixel in %box2.
* (3) For a zero or negative horizontal overlap, o <= 0, the minimum
* difference in the x-component between pixels on the boundaries
* of the two boxes is d = -o + 1.
* (4) Likewise for vertical overlaps.
*
*/
l_ok
boxOverlapDistance(BOX *box1,
BOX *box2,
l_int32 *ph_ovl,
l_int32 *pv_ovl)
{
l_int32 l1, t1, w1, h1, r1, b1, l2, t2, w2, h2, r2, b2, valid1, valid2;
PROCNAME("boxOverlapDistance");
if (!ph_ovl && !pv_ovl)
return ERROR_INT("nothing to do", procName, 1);
if (ph_ovl) *ph_ovl = 0;
if (pv_ovl) *pv_ovl = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
if (ph_ovl) {
boxGetGeometry(box1, &l1, NULL, &w1, NULL);
boxGetGeometry(box2, &l2, NULL, &w2, NULL);
r1 = l1 + w1; /* 1 pixel to the right of box 1 */
r2 = l2 + w2;
if (l2 >= l1)
*ph_ovl = r1 - l2;
else
*ph_ovl = r2 - l1;
}
if (pv_ovl) {
boxGetGeometry(box1, NULL, &t1, NULL, &h1);
boxGetGeometry(box2, NULL, &t2, NULL, &h2);
b1 = t1 + h1; /* 1 pixel below box 1 */
b2 = t2 + h2;
if (t2 >= t1)
*pv_ovl = b1 - t2;
else
*pv_ovl = b2 - t1;
}
return 0;
}
/*!
* \brief boxSeparationDistance()
*
* \param[in] box1, box2 two boxes, in any order
* \param[out] ph_sep horizontal separation
* \param[out] pv_sep vertical separation
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This measures the Manhattan distance between the closest points
* on the boundaries of the two boxes. When the boxes overlap
* (including touching along a line or at a corner), the
* horizontal and vertical distances are 0.
* (2) The distances represent the horizontal and vertical separation
* of the two boxes. The boxes have a nonzero intersection when
* both the horizontal and vertical overlaps are positive, and
* for that case both horizontal and vertical separation
* distances are 0.
* (3) If the horizontal overlap of the boxes is positive, the
* horizontal separation between nearest points on respective
* boundaries is 0, and likewise for the vertical overlap.
* (4) If the horizontal overlap ho <= 0, the horizontal
* separation between nearest points is d = -ho + 1.
* Likewise, if the vertical overlap vo <= 0, the vertical
* separation between nearest points is d = -vo + 1.
*
*/
l_ok
boxSeparationDistance(BOX *box1,
BOX *box2,
l_int32 *ph_sep,
l_int32 *pv_sep)
{
l_int32 h_ovl, v_ovl, valid1, valid2;
PROCNAME("boxSeparationDistance");
if (ph_sep) *ph_sep = 0;
if (pv_sep) *pv_sep = 0;
if (!ph_sep || !pv_sep)
return ERROR_INT("&h_sep and &v_sep not both defined", procName, 1);
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
boxOverlapDistance(box1, box2, &h_ovl, &v_ovl);
if (h_ovl <= 0)
*ph_sep = -h_ovl + 1;
if (v_ovl <= 0)
*pv_sep = -v_ovl + 1;
return 0;
}
/*!
* \brief boxCompareSize()
*
* \param[in] box1, box2
* \param[in] type L_SORT_BY_WIDTH, L_SORT_BY_HEIGHT,
* L_SORT_BY_MAX_DIMENSION, L_SORT_BY_PERIMETER,
* L_SORT_BY_AREA,
* \param[out] prel 1 if box1 > box2, 0 if the same, -1 if box1 < box2
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) We're re-using the SORT enum for these comparisons.
*
*/
l_ok
boxCompareSize(BOX *box1,
BOX *box2,
l_int32 type,
l_int32 *prel)
{
l_int32 w1, h1, w2, h2, size1, size2, valid1, valid2;
PROCNAME("boxCompareSize");
if (!prel)
return ERROR_INT("&rel not defined", procName, 1);
*prel = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
if (type != L_SORT_BY_WIDTH && type != L_SORT_BY_HEIGHT &&
type != L_SORT_BY_MAX_DIMENSION && type != L_SORT_BY_PERIMETER &&
type != L_SORT_BY_AREA)
return ERROR_INT("invalid compare type", procName, 1);
boxGetGeometry(box1, NULL, NULL, &w1, &h1);
boxGetGeometry(box2, NULL, NULL, &w2, &h2);
if (type == L_SORT_BY_WIDTH) {
*prel = (w1 > w2) ? 1 : ((w1 == w2) ? 0 : -1);
} else if (type == L_SORT_BY_HEIGHT) {
*prel = (h1 > h2) ? 1 : ((h1 == h2) ? 0 : -1);
} else if (type == L_SORT_BY_MAX_DIMENSION) {
size1 = L_MAX(w1, h1);
size2 = L_MAX(w2, h2);
*prel = (size1 > size2) ? 1 : ((size1 == size2) ? 0 : -1);
} else if (type == L_SORT_BY_PERIMETER) {
size1 = w1 + h1;
size2 = w2 + h2;
*prel = (size1 > size2) ? 1 : ((size1 == size2) ? 0 : -1);
} else if (type == L_SORT_BY_AREA) {
size1 = w1 * h1;
size2 = w2 * h2;
*prel = (size1 > size2) ? 1 : ((size1 == size2) ? 0 : -1);
}
return 0;
}
/*!
* \brief boxContainsPt()
*
* \param[in] box
* \param[in] x, y a point
* \param[out] pcontains 1 if box contains point; 0 otherwise
* \return 0 if OK, 1 on error.
*/
l_ok
boxContainsPt(BOX *box,
l_float32 x,
l_float32 y,
l_int32 *pcontains)
{
l_int32 bx, by, bw, bh;
PROCNAME("boxContainsPt");
if (!pcontains)
return ERROR_INT("&contains not defined", procName, 1);
*pcontains = 0;
if (!box)
return ERROR_INT("&box not defined", procName, 1);
boxGetGeometry(box, &bx, &by, &bw, &bh);
if (x >= bx && x < bx + bw && y >= by && y < by + bh)
*pcontains = 1;
return 0;
}
/*!
* \brief boxaGetNearestToPt()
*
* \param[in] boxa
* \param[in] x, y point
* \return box with centroid closest to the given point [x,y],
* or NULL if no boxes in boxa
*
*
* Notes:
* (1) Uses euclidean distance between centroid and point.
*
*/
BOX *
boxaGetNearestToPt(BOXA *boxa,
l_int32 x,
l_int32 y)
{
l_int32 i, n, minindex;
l_float32 delx, dely, dist, mindist, cx, cy;
BOX *box;
PROCNAME("boxaGetNearestToPt");
if (!boxa)
return (BOX *)ERROR_PTR("boxa not defined", procName, NULL);
if ((n = boxaGetCount(boxa)) == 0)
return (BOX *)ERROR_PTR("n = 0", procName, NULL);
mindist = 1000000000.;
minindex = 0;
for (i = 0; i < n; i++) {
if ((box = boxaGetValidBox(boxa, i, L_CLONE)) == NULL)
continue;
boxGetCenter(box, &cx, &cy);
delx = (l_float32)(cx - x);
dely = (l_float32)(cy - y);
dist = delx * delx + dely * dely;
if (dist < mindist) {
minindex = i;
mindist = dist;
}
boxDestroy(&box);
}
return boxaGetBox(boxa, minindex, L_COPY);
}
/*!
* \brief boxaGetNearestToLine()
*
* \param[in] boxa
* \param[in] x, y (y = -1 for vertical line; x = -1 for horiz line)
* \return box with centroid closest to the given line,
* or NULL if no boxes in boxa
*
*
* Notes:
* (1) For a horizontal line at some value y, get the minimum of the
* distance |yc - y| from the box centroid yc value to y;
* likewise minimize |xc - x| for a vertical line at x.
* (2) Input y < 0, x >= 0 to indicate a vertical line at x, and
* x < 0, y >= 0 for a horizontal line at y.
*
*/
BOX *
boxaGetNearestToLine(BOXA *boxa,
l_int32 x,
l_int32 y)
{
l_int32 i, n, minindex;
l_float32 dist, mindist, cx, cy;
BOX *box;
PROCNAME("boxaGetNearestToLine");
if (!boxa)
return (BOX *)ERROR_PTR("boxa not defined", procName, NULL);
if ((n = boxaGetCount(boxa)) == 0)
return (BOX *)ERROR_PTR("n = 0", procName, NULL);
if (y >= 0 && x >= 0)
return (BOX *)ERROR_PTR("either x or y must be < 0", procName, NULL);
if (y < 0 && x < 0)
return (BOX *)ERROR_PTR("either x or y must be >= 0", procName, NULL);
mindist = 1000000000.;
minindex = 0;
for (i = 0; i < n; i++) {
if ((box = boxaGetValidBox(boxa, i, L_CLONE)) == NULL)
continue;
boxGetCenter(box, &cx, &cy);
if (x >= 0)
dist = L_ABS(cx - (l_float32)x);
else /* y >= 0 */
dist = L_ABS(cy - (l_float32)y);
if (dist < mindist) {
minindex = i;
mindist = dist;
}
boxDestroy(&box);
}
return boxaGetBox(boxa, minindex, L_COPY);
}
/*!
* \brief boxaFindNearestBoxes()
*
* \param[in] boxa either unsorted, or 2D sorted in LR/TB scan order
* \param[in] dist_select L_NON_NEGATIVE, L_ALL
* \param[in] range search distance from box i; use 0 to search
* entire boxa (e.g., if it's not 2D sorted)
* \param[out] pnaaindex for each box in %boxa, contains a numa of 4
* box indices (per direction) of the nearest box
* \param[out] pnaadist for each box in %boxa, this contains a numa
* \return 0 if OK, 1 on error
*
* Notes:
* (1) See boxaGetNearestByDirection() for usage of %dist_select
* and %range.
*
*/
l_ok
boxaFindNearestBoxes(BOXA *boxa,
l_int32 dist_select,
l_int32 range,
NUMAA **pnaaindex,
NUMAA **pnaadist)
{
l_int32 i, n, index, dist;
NUMA *nai, *nad;
NUMAA *naai, *naad;
PROCNAME("boxaFindNearestBoxes");
if (pnaaindex) *pnaaindex = NULL;
if (pnaadist) *pnaadist = NULL;
if (!pnaaindex)
return ERROR_INT("&naaindex not defined", procName, 1);
if (!pnaadist)
return ERROR_INT("&naadist not defined", procName, 1);
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
n = boxaGetCount(boxa);
naai = numaaCreate(n);
naad = numaaCreate(n);
*pnaaindex = naai;
*pnaadist = naad;
for (i = 0; i < n; i++) {
nai = numaCreate(4);
nad = numaCreate(4);
boxaGetNearestByDirection(boxa, i, L_FROM_LEFT, dist_select,
range, &index, &dist);
numaAddNumber(nai, index);
numaAddNumber(nad, dist);
boxaGetNearestByDirection(boxa, i, L_FROM_RIGHT, dist_select,
range, &index, &dist);
numaAddNumber(nai, index);
numaAddNumber(nad, dist);
boxaGetNearestByDirection(boxa, i, L_FROM_TOP, dist_select,
range, &index, &dist);
numaAddNumber(nai, index);
numaAddNumber(nad, dist);
boxaGetNearestByDirection(boxa, i, L_FROM_BOT, dist_select,
range, &index, &dist);
numaAddNumber(nai, index);
numaAddNumber(nad, dist);
numaaAddNuma(naai, nai, L_INSERT);
numaaAddNuma(naad, nad, L_INSERT);
}
return 0;
}
/*!
* \brief boxaGetNearestByDirection()
*
* \param[in] boxa either unsorted, or 2D sorted in LR/TB scan order
* \param[in] i box we test against
* \param[in] dir direction to look: L_FROM_LEFT, L_FROM_RIGHT,
* L_FROM_TOP, L_FROM_BOT
* \param[in] dist_select L_NON_NEGATIVE, L_ALL
* \param[in] range search distance from box i; use 0 to search
* entire boxa (e.g., if it's not 2D sorted)
* \param[out] pindex index in boxa of nearest box with overlapping
* coordinates in the indicated direction;
* -1 if there is no box
* \param[out] pdist distance of the nearest box in the indicated
* direction; 100000 if no box
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) For efficiency, use a LR/TD sorted %boxa, which can be
* made by flattening a 2D sorted boxaa. In that case,
* %range can be some positive integer like 50.
* (2) If boxes overlap, the distance will be < 0. Use %dist_select
* to determine if these should count or not. If L_ALL, then
* one box will match as the nearest to another in 2 or more
* directions.
*
*/
l_ok
boxaGetNearestByDirection(BOXA *boxa,
l_int32 i,
l_int32 dir,
l_int32 dist_select,
l_int32 range,
l_int32 *pindex,
l_int32 *pdist)
{
l_int32 j, jmin, jmax, n, mindist, dist, index;
l_int32 x, y, w, h, bx, by, bw, bh;
PROCNAME("boxaGetNearestByDirection");
if (pindex) *pindex = -1;
if (pdist) *pdist = 100000;
if (!pindex)
return ERROR_INT("&index not defined", procName, 1);
if (!pdist)
return ERROR_INT("&dist not defined", procName, 1);
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
if (dir != L_FROM_LEFT && dir != L_FROM_RIGHT &&
dir != L_FROM_TOP && dir != L_FROM_BOT)
return ERROR_INT("invalid dir", procName, 1);
if (dist_select != L_NON_NEGATIVE && dist_select != L_ALL)
return ERROR_INT("invalid dist_select", procName, 1);
n = boxaGetCount(boxa);
if (i < 0 || i >= n)
return ERROR_INT("invalid box index", procName, 1);
jmin = (range <= 0) ? 0 : L_MAX(0, i - range);
jmax = (range <= 0) ? n - 1 : L_MIN(n -1, i + range);
boxaGetBoxGeometry(boxa, i, &x, &y, &w, &h);
mindist = 100000;
index = -1;
if (dir == L_FROM_LEFT || dir == L_FROM_RIGHT) {
for (j = jmin; j <= jmax; j++) {
if (j == i) continue;
boxaGetBoxGeometry(boxa, j, &bx, &by, &bw, &bh);
if ((bx >= x && dir == L_FROM_LEFT) || /* not to the left */
(x >= bx && dir == L_FROM_RIGHT)) /* not to the right */
continue;
if (boxHasOverlapInXorY(y, h, by, bh) == 1) {
dist = boxGetDistanceInXorY(x, w, bx, bw);
if (dist_select == L_NON_NEGATIVE && dist < 0) continue;
if (dist < mindist) {
mindist = dist;
index = j;
}
}
}
} else if (dir == L_FROM_TOP || dir == L_FROM_BOT) {
for (j = jmin; j <= jmax; j++) {
if (j == i) continue;
boxaGetBoxGeometry(boxa, j, &bx, &by, &bw, &bh);
if ((by >= y && dir == L_FROM_TOP) || /* not above */
(y >= by && dir == L_FROM_BOT)) /* not below */
continue;
if (boxHasOverlapInXorY(x, w, bx, bw) == 1) {
dist = boxGetDistanceInXorY(y, h, by, bh);
if (dist_select == L_NON_NEGATIVE && dist < 0) continue;
if (dist < mindist) {
mindist = dist;
index = j;
}
}
}
}
*pindex = index;
*pdist = mindist;
return 0;
}
/*!
* \brief boxHasOverlapInXorY()
*
* \param[in] c1 left or top coordinate of box1
* \param[in] s1 width or height of box1
* \param[in] c2 left or top coordinate of box2
* \param[in] s2 width or height of box2
* \return 0 if no overlap; 1 if any overlap
*
*
* Notes:
* (1) Like boxGetDistanceInXorY(), this is used for overlaps both in
* x (which projected vertically) and in y (projected horizontally)
*
*/
static l_int32
boxHasOverlapInXorY(l_int32 c1,
l_int32 s1,
l_int32 c2,
l_int32 s2)
{
l_int32 ovlp;
if (c1 > c2)
ovlp = c2 + s2 - 1 - c1;
else
ovlp = c1 + s1 - 1 - c2;
return (ovlp < 0) ? 0 : 1;
}
/*!
* \brief boxGetDistanceInXorY()
*
* \param[in] c1 left or top coordinate of box1
* \param[in] s1 width or height of box1
* \param[in] c2 left or top coordinate of box2
* \param[in] s2 width or height of box2
* \return distance between them (if < 0, box2 overlaps box1 in the
* dimension considered)
*/
static l_int32
boxGetDistanceInXorY(l_int32 c1,
l_int32 s1,
l_int32 c2,
l_int32 s2)
{
l_int32 dist;
if (c1 > c2)
dist = c1 - (c2 + s2 - 1);
else
dist = c2 - (c1 + s1 - 1);
return dist;
}
/*!
* \brief boxGetCenter()
*
* \param[in] box
* \param[out] pcx, pcy location of center of box
* \return 0 if OK, 1 on error or if box is not valid
*/
l_ok
boxGetCenter(BOX *box,
l_float32 *pcx,
l_float32 *pcy)
{
l_int32 x, y, w, h;
PROCNAME("boxGetCenter");
if (pcx) *pcx = 0;
if (pcy) *pcy = 0;
if (!pcx || !pcy)
return ERROR_INT("&cx, &cy not both defined", procName, 1);
if (!box)
return ERROR_INT("box not defined", procName, 1);
boxGetGeometry(box, &x, &y, &w, &h);
if (w == 0 || h == 0) return 1;
*pcx = (l_float32)(x + 0.5 * w);
*pcy = (l_float32)(y + 0.5 * h);
return 0;
}
/*!
* \brief boxIntersectByLine()
*
* \param[in] box
* \param[in] x, y point that line goes through
* \param[in] slope of line
* \param[out] px1, py1 1st point of intersection with box
* \param[out] px2, py2 2nd point of intersection with box
* \param[out] pn number of points of intersection
* \return 0 if OK, 1 on error or if box is not valid
*
*
* Notes:
* (1) If the intersection is at only one point (a corner), the
* coordinates are returned in (x1, y1).
* (2) Represent a vertical line by one with a large but finite slope.
*
*/
l_ok
boxIntersectByLine(BOX *box,
l_int32 x,
l_int32 y,
l_float32 slope,
l_int32 *px1,
l_int32 *py1,
l_int32 *px2,
l_int32 *py2,
l_int32 *pn)
{
l_int32 bx, by, bw, bh, xp, yp, xt, yt, i, n;
l_float32 invslope;
PTA *pta;
PROCNAME("boxIntersectByLine");
if (px1) *px1 = 0;
if (px2) *px2 = 0;
if (py1) *py1 = 0;
if (py2) *py2 = 0;
if (pn) *pn = 0;
if (!px1 || !py1 || !px2 || !py2)
return ERROR_INT("&x1, &y1, &x2, &y2 not all defined", procName, 1);
if (!pn)
return ERROR_INT("&n not defined", procName, 1);
if (!box)
return ERROR_INT("box not defined", procName, 1);
boxGetGeometry(box, &bx, &by, &bw, &bh);
if (bw == 0 || bh == 0) return 1;
if (slope == 0.0) {
if (y >= by && y < by + bh) {
*py1 = *py2 = y;
*px1 = bx;
*px2 = bx + bw - 1;
}
return 0;
}
if (slope > 1000000.0) {
if (x >= bx && x < bx + bw) {
*px1 = *px2 = x;
*py1 = by;
*py2 = by + bh - 1;
}
return 0;
}
/* Intersection with top and bottom lines of box */
pta = ptaCreate(2);
invslope = 1.0 / slope;
xp = (l_int32)(x + invslope * (y - by));
if (xp >= bx && xp < bx + bw)
ptaAddPt(pta, xp, by);
xp = (l_int32)(x + invslope * (y - by - bh + 1));
if (xp >= bx && xp < bx + bw)
ptaAddPt(pta, xp, by + bh - 1);
/* Intersection with left and right lines of box */
yp = (l_int32)(y + slope * (x - bx));
if (yp >= by && yp < by + bh)
ptaAddPt(pta, bx, yp);
yp = (l_int32)(y + slope * (x - bx - bw + 1));
if (yp >= by && yp < by + bh)
ptaAddPt(pta, bx + bw - 1, yp);
/* There is a maximum of 2 unique points; remove duplicates. */
n = ptaGetCount(pta);
if (n > 0) {
ptaGetIPt(pta, 0, px1, py1); /* accept the first one */
*pn = 1;
}
for (i = 1; i < n; i++) {
ptaGetIPt(pta, i, &xt, &yt);
if ((*px1 != xt) || (*py1 != yt)) {
*px2 = xt;
*py2 = yt;
*pn = 2;
break;
}
}
ptaDestroy(&pta);
return 0;
}
/*!
* \brief boxClipToRectangle()
*
* \param[in] box
* \param[in] wi, hi rectangle representing image
* \return part of box within given rectangle, or NULL on error
* or if box is entirely outside the rectangle
*
*
* Notes:
* (1) This can be used to clip a rectangle to an image.
* The clipping rectangle is assumed to have a UL corner at (0, 0),
* and a LR corner at (wi - 1, hi - 1).
*
*/
BOX *
boxClipToRectangle(BOX *box,
l_int32 wi,
l_int32 hi)
{
BOX *boxd;
PROCNAME("boxClipToRectangle");
if (!box)
return (BOX *)ERROR_PTR("box not defined", procName, NULL);
if (box->x >= wi || box->y >= hi ||
box->x + box->w <= 0 || box->y + box->h <= 0)
return (BOX *)ERROR_PTR("box outside rectangle", procName, NULL);
boxd = boxCopy(box);
if (boxd->x < 0) {
boxd->w += boxd->x;
boxd->x = 0;
}
if (boxd->y < 0) {
boxd->h += boxd->y;
boxd->y = 0;
}
if (boxd->x + boxd->w > wi)
boxd->w = wi - boxd->x;
if (boxd->y + boxd->h > hi)
boxd->h = hi - boxd->y;
return boxd;
}
/*!
* \brief boxClipToRectangleParams()
*
* \param[in] box [optional] requested box; can be null
* \param[in] w, h clipping box size; typ. the size of an image
* \param[out] pxstart start x coordinate
* \param[out] pystart start y coordinate
* \param[out] pxend one pixel beyond clipping box
* \param[out] pyend one pixel beyond clipping box
* \param[out] pbw [optional] clipped width
* \param[out] pbh [optional] clipped height
* \return 0 if OK; 1 on error
*
*
* Notes:
* (1) The return value should be checked. If it is 1, the
* returned parameter values are bogus.
* (2) This simplifies the selection of pixel locations within
* a given rectangle:
* for (i = ystart; i < yend; i++ {
* ...
* for (j = xstart; j < xend; j++ {
* ....
*
*/
l_ok
boxClipToRectangleParams(BOX *box,
l_int32 w,
l_int32 h,
l_int32 *pxstart,
l_int32 *pystart,
l_int32 *pxend,
l_int32 *pyend,
l_int32 *pbw,
l_int32 *pbh)
{
l_int32 bw, bh;
BOX *boxc;
PROCNAME("boxClipToRectangleParams");
if (pxstart) *pxstart = 0;
if (pystart) *pystart = 0;
if (pxend) *pxend = w;
if (pyend) *pyend = h;
if (pbw) *pbw = w;
if (pbh) *pbh = h;
if (!pxstart || !pystart || !pxend || !pyend)
return ERROR_INT("invalid ptr input", procName, 1);
if (!box) return 0;
if ((boxc = boxClipToRectangle(box, w, h)) == NULL)
return ERROR_INT("box outside image", procName, 1);
boxGetGeometry(boxc, pxstart, pystart, &bw, &bh);
boxDestroy(&boxc);
if (pbw) *pbw = bw;
if (pbh) *pbh = bh;
if (bw == 0 || bh == 0)
return ERROR_INT("invalid clipping box", procName, 1);
*pxend = *pxstart + bw; /* 1 past the end */
*pyend = *pystart + bh; /* 1 past the end */
return 0;
}
/*!
* \brief boxRelocateOneSide()
*
* \param[in] boxd [optional]; this can be null, equal to boxs,
* or different from boxs;
* \param[in] boxs starting box; to have one side relocated
* \param[in] loc new location of the side that is changing
* \param[in] sideflag L_FROM_LEFT, etc., indicating the side that moves
* \return boxd, or NULL on error or if the computed boxd has
* width or height <= 0.
*
*
* Notes:
* (1) Set boxd == NULL to get new box; boxd == boxs for in-place;
* or otherwise to resize existing boxd.
* (2) For usage, suggest one of these:
* boxd = boxRelocateOneSide(NULL, boxs, ...); // new
* boxRelocateOneSide(boxs, boxs, ...); // in-place
* boxRelocateOneSide(boxd, boxs, ...); // other
*
*/
BOX *
boxRelocateOneSide(BOX *boxd,
BOX *boxs,
l_int32 loc,
l_int32 sideflag)
{
l_int32 x, y, w, h;
PROCNAME("boxRelocateOneSide");
if (!boxs)
return (BOX *)ERROR_PTR("boxs not defined", procName, NULL);
if (!boxd)
boxd = boxCopy(boxs);
boxGetGeometry(boxs, &x, &y, &w, &h);
if (w == 0 || h == 0)
return boxd;
if (sideflag == L_FROM_LEFT)
boxSetGeometry(boxd, loc, -1, w + x - loc, -1);
else if (sideflag == L_FROM_RIGHT)
boxSetGeometry(boxd, -1, -1, loc - x + 1, -1);
else if (sideflag == L_FROM_TOP)
boxSetGeometry(boxd, -1, loc, -1, h + y - loc);
else if (sideflag == L_FROM_BOT)
boxSetGeometry(boxd, -1, -1, -1, loc - y + 1);
return boxd;
}
/*!
* \brief boxaAdjustSides()
*
* \param[in] boxas
* \param[in] delleft, delright, deltop, delbot changes in location of
* each side for each box
* \return boxad, or NULL on error
*
*
* Notes:
* (1) New box dimensions are cropped at left and top to x >= 0 and y >= 0.
* (2) If the width or height of a box goes to 0, we generate a box with
* w == 1 and h == 1, as a placeholder.
* (3) See boxAdjustSides().
*
*/
BOXA *
boxaAdjustSides(BOXA *boxas,
l_int32 delleft,
l_int32 delright,
l_int32 deltop,
l_int32 delbot)
{
l_int32 n, i, x, y;
BOX *box1, *box2;
BOXA *boxad;
PROCNAME("boxaAdjustSides");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
n = boxaGetCount(boxas);
boxad = boxaCreate(n);
for (i = 0; i < n; i++) {
box1 = boxaGetBox(boxas, i, L_COPY);
box2 = boxAdjustSides(NULL, box1, delleft, delright, deltop, delbot);
if (!box2) {
boxGetGeometry(box1, &x, &y, NULL, NULL);
box2 = boxCreate(x, y, 1, 1);
}
boxaAddBox(boxad, box2, L_INSERT);
boxDestroy(&box1);
}
return boxad;
}
/*!
* \brief boxaAdjustBoxSides()
*
* \param[in] boxas
* \param[in] index
* \param[in] delleft, delright, deltop, delbot changes to box side locs
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) In-place operation on a box in a boxa.
* (2) New box dimensions are cropped at left and top to x >= 0 and y >= 0.
* (3) If a box ends up with no area, an error message is emitted,
* but the box dimensions are not changed.
* (4) See boxaAdjustSides().
*
*/
l_ok
boxaAdjustBoxSides(BOXA *boxa,
l_int32 index,
l_int32 delleft,
l_int32 delright,
l_int32 deltop,
l_int32 delbot)
{
BOX *box;
PROCNAME("boxaAdjustBoxSides");
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
if ((box = boxaGetBox(boxa, index, L_CLONE)) == NULL)
return ERROR_INT("invalid index", procName, 1);
boxAdjustSides(box, box, delleft, delright, deltop, delbot);
boxDestroy(&box); /* the clone */
return 0;
}
/*!
* \brief boxAdjustSides()
*
* \param[in] boxd [optional]; this can be null, equal to boxs,
* or different from boxs
* \param[in] boxs starting box; to have sides adjusted
* \param[in] delleft, delright, deltop, delbot changes in location
* of each side
* \return boxd, or NULL on error or if the computed boxd has
* width or height <= 0.
*
*
* Notes:
* (1) Set boxd == NULL to get new box; boxd == boxs for in-place;
* or otherwise to resize existing boxd.
* (2) For usage, suggest one of these:
* boxd = boxAdjustSides(NULL, boxs, ...); // new
* boxAdjustSides(boxs, boxs, ...); // in-place
* boxAdjustSides(boxd, boxs, ...); // other
* (3) New box dimensions are cropped at left and top to x >= 0 and y >= 0.
* (4) For example, to expand in-place by 20 pixels on each side, use
* boxAdjustSides(box, box, -20, 20, -20, 20);
*
*/
BOX *
boxAdjustSides(BOX *boxd,
BOX *boxs,
l_int32 delleft,
l_int32 delright,
l_int32 deltop,
l_int32 delbot)
{
l_int32 x, y, w, h, xl, xr, yt, yb, wnew, hnew;
PROCNAME("boxAdjustSides");
if (!boxs)
return (BOX *)ERROR_PTR("boxs not defined", procName, NULL);
boxGetGeometry(boxs, &x, &y, &w, &h);
xl = L_MAX(0, x + delleft);
yt = L_MAX(0, y + deltop);
xr = x + w + delright; /* one pixel beyond right edge */
yb = y + h + delbot; /* one pixel below bottom edge */
wnew = xr - xl;
hnew = yb - yt;
if (wnew < 1 || hnew < 1)
return (BOX *)ERROR_PTR("boxd has 0 area", procName, NULL);
if (!boxd)
return boxCreate(xl, yt, wnew, hnew);
boxSetGeometry(boxd, xl, yt, wnew, hnew);
return boxd;
}
/*!
* \brief boxaSetSide()
*
* \param[in] boxad use NULL to get a new one; same as boxas for in-place
* \param[in] boxas
* \param[in] side L_SET_LEFT, L_SET_RIGHT, L_SET_TOP, L_SET_BOT
* \param[in] val location to set for given side, for each box
* \param[in] thresh min abs difference to cause resetting to %val
* \return boxad, or NULL on error
*
*
* Notes:
* (1) Sets the given side of each box. Use boxad == NULL for a new
* boxa, and boxad == boxas for in-place.
* (2) Use one of these:
* boxad = boxaSetSide(NULL, boxas, ...); // new
* boxaSetSide(boxas, boxas, ...); // in-place
*
*/
BOXA *
boxaSetSide(BOXA *boxad,
BOXA *boxas,
l_int32 side,
l_int32 val,
l_int32 thresh)
{
l_int32 n, i;
BOX *box;
PROCNAME("boxaSetSide");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (boxad && (boxas != boxad))
return (BOXA *)ERROR_PTR("not in-place", procName, NULL);
if (side != L_SET_LEFT && side != L_SET_RIGHT &&
side != L_SET_TOP && side != L_SET_BOT)
return (BOXA *)ERROR_PTR("invalid side", procName, NULL);
if (val < 0)
return (BOXA *)ERROR_PTR("val < 0", procName, NULL);
if (!boxad)
boxad = boxaCopy(boxas, L_COPY);
n = boxaGetCount(boxad);
for (i = 0; i < n; i++) {
box = boxaGetBox(boxad, i, L_CLONE);
boxSetSide(box, side, val, thresh);
boxDestroy(&box); /* the clone */
}
return boxad;
}
/*!
* \brief boxSetSide()
*
* \param[in] boxs
* \param[in] side L_SET_LEFT, L_SET_RIGHT, L_SET_TOP, L_SET_BOT
* \param[in] val location to set for given side, for each box
* \param[in] thresh min abs difference to cause resetting to %val
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) In-place operation.
* (2) Use %thresh = 0 to definitely set the side to %val.
*
*/
l_ok
boxSetSide(BOX *boxs,
l_int32 side,
l_int32 val,
l_int32 thresh)
{
l_int32 x, y, w, h, diff;
PROCNAME("boxSetSide");
if (!boxs)
return ERROR_INT("box not defined", procName, 1);
if (side != L_SET_LEFT && side != L_SET_RIGHT &&
side != L_SET_TOP && side != L_SET_BOT)
return ERROR_INT("invalid side", procName, 1);
if (val < 0)
return ERROR_INT("val < 0", procName, 1);
boxGetGeometry(boxs, &x, &y, &w, &h);
if (side == L_SET_LEFT) {
diff = x - val;
if (L_ABS(diff) >= thresh)
boxSetGeometry(boxs, val, y, w + diff, h);
} else if (side == L_SET_RIGHT) {
diff = x + w -1 - val;
if (L_ABS(diff) >= thresh)
boxSetGeometry(boxs, x, y, val - x + 1, h);
} else if (side == L_SET_TOP) {
diff = y - val;
if (L_ABS(diff) >= thresh)
boxSetGeometry(boxs, x, val, w, h + diff);
} else { /* side == L_SET_BOT */
diff = y + h - 1 - val;
if (L_ABS(diff) >= thresh)
boxSetGeometry(boxs, x, y, w, val - y + 1);
}
return 0;
}
/*!
* \brief boxaAdjustWidthToTarget()
*
* \param[in] boxad use NULL to get a new one; same as boxas for in-place
* \param[in] boxas
* \param[in] sides L_ADJUST_LEFT, L_ADJUST_RIGHT, L_ADJUST_LEFT_AND_RIGHT
* \param[in] target target width if differs by more than thresh
* \param[in] thresh min abs difference in width to cause adjustment
* \return boxad, or NULL on error
*
*
* Notes:
* (1) Conditionally adjusts the width of each box, by moving
* the indicated edges (left and/or right) if the width differs
* by %thresh or more from %target.
* (2) Use boxad == NULL for a new boxa, and boxad == boxas for in-place.
* Use one of these:
* boxad = boxaAdjustWidthToTarget(NULL, boxas, ...); // new
* boxaAdjustWidthToTarget(boxas, boxas, ...); // in-place
*
*/
BOXA *
boxaAdjustWidthToTarget(BOXA *boxad,
BOXA *boxas,
l_int32 sides,
l_int32 target,
l_int32 thresh)
{
l_int32 x, y, w, h, n, i, diff;
BOX *box;
PROCNAME("boxaAdjustWidthToTarget");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (boxad && (boxas != boxad))
return (BOXA *)ERROR_PTR("not in-place", procName, NULL);
if (sides != L_ADJUST_LEFT && sides != L_ADJUST_RIGHT &&
sides != L_ADJUST_LEFT_AND_RIGHT)
return (BOXA *)ERROR_PTR("invalid sides", procName, NULL);
if (target < 1)
return (BOXA *)ERROR_PTR("target < 1", procName, NULL);
if (!boxad)
boxad = boxaCopy(boxas, L_COPY);
n = boxaGetCount(boxad);
for (i = 0; i < n; i++) {
if ((box = boxaGetValidBox(boxad, i, L_CLONE)) == NULL)
continue;
boxGetGeometry(box, &x, &y, &w, &h);
diff = w - target;
if (sides == L_ADJUST_LEFT) {
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, L_MAX(0, x + diff), y, target, h);
} else if (sides == L_ADJUST_RIGHT) {
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, x, y, target, h);
} else { /* sides == L_ADJUST_LEFT_AND_RIGHT */
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, L_MAX(0, x + diff/2), y, target, h);
}
boxDestroy(&box);
}
return boxad;
}
/*!
* \brief boxaAdjustHeightToTarget()
*
* \param[in] boxad use NULL to get a new one
* \param[in] boxas
* \param[in] sides L_ADJUST_TOP, L_ADJUST_BOT, L_ADJUST_TOP_AND_BOT
* \param[in] target target height if differs by more than thresh
* \param[in] thresh min abs difference in height to cause adjustment
* \return boxad, or NULL on error
*
*
* Notes:
* (1) Conditionally adjusts the height of each box, by moving
* the indicated edges (top and/or bot) if the height differs
* by %thresh or more from %target.
* (2) Use boxad == NULL for a new boxa, and boxad == boxas for in-place.
* Use one of these:
* boxad = boxaAdjustHeightToTarget(NULL, boxas, ...); // new
* boxaAdjustHeightToTarget(boxas, boxas, ...); // in-place
*
*/
BOXA *
boxaAdjustHeightToTarget(BOXA *boxad,
BOXA *boxas,
l_int32 sides,
l_int32 target,
l_int32 thresh)
{
l_int32 x, y, w, h, n, i, diff;
BOX *box;
PROCNAME("boxaAdjustHeightToTarget");
if (!boxas)
return (BOXA *)ERROR_PTR("boxas not defined", procName, NULL);
if (boxad && (boxas != boxad))
return (BOXA *)ERROR_PTR("not in-place", procName, NULL);
if (sides != L_ADJUST_TOP && sides != L_ADJUST_BOT &&
sides != L_ADJUST_TOP_AND_BOT)
return (BOXA *)ERROR_PTR("invalid sides", procName, NULL);
if (target < 1)
return (BOXA *)ERROR_PTR("target < 1", procName, NULL);
if (!boxad)
boxad = boxaCopy(boxas, L_COPY);
n = boxaGetCount(boxad);
for (i = 0; i < n; i++) {
if ((box = boxaGetValidBox(boxad, i, L_CLONE)) == NULL)
continue;
boxGetGeometry(box, &x, &y, &w, &h);
diff = h - target;
if (sides == L_ADJUST_TOP) {
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, x, L_MAX(0, y + diff), w, target);
} else if (sides == L_ADJUST_BOT) {
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, x, y, w, target);
} else { /* sides == L_ADJUST_TOP_AND_BOT */
if (L_ABS(diff) >= thresh)
boxSetGeometry(box, x, L_MAX(0, y + diff/2), w, target);
}
boxDestroy(&box);
}
return boxad;
}
/*!
* \brief boxEqual()
*
* \param[in] box1
* \param[in] box2
* \param[out] psame 1 if equal; 0 otherwise
* \return 0 if OK, 1 on error
*/
l_ok
boxEqual(BOX *box1,
BOX *box2,
l_int32 *psame)
{
PROCNAME("boxEqual");
if (!psame)
return ERROR_INT("&same not defined", procName, 1);
*psame = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
if (box1->x == box2->x && box1->y == box2->y &&
box1->w == box2->w && box1->h == box2->h)
*psame = 1;
return 0;
}
/*!
* \brief boxaEqual()
*
* \param[in] boxa1
* \param[in] boxa2
* \param[in] maxdist
* \param[out] pnaindex [optional] index array of correspondences
* \param[out] psame 1 if equal; 0 otherwise
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) The two boxa are the "same" if they contain the same
* boxes and each box is within %maxdist of its counterpart
* in their positions within the boxa. This allows for
* small rearrangements. Use 0 for maxdist if the boxa
* must be identical.
* (2) This applies only to geometry and ordering; refcounts
* are not considered.
* (3) %maxdist allows some latitude in the ordering of the boxes.
* For the boxa to be the "same", corresponding boxes must
* be within %maxdist of each other. Note that for large
* %maxdist, we should use a hash function for efficiency.
* (4) naindex[i] gives the position of the box in boxa2 that
* corresponds to box i in boxa1. It is only returned if the
* boxa are equal.
*
*/
l_ok
boxaEqual(BOXA *boxa1,
BOXA *boxa2,
l_int32 maxdist,
NUMA **pnaindex,
l_int32 *psame)
{
l_int32 i, j, n, jstart, jend, found, samebox;
l_int32 *countarray;
BOX *box1, *box2;
NUMA *na;
PROCNAME("boxaEqual");
if (pnaindex) *pnaindex = NULL;
if (!psame)
return ERROR_INT("&same not defined", procName, 1);
*psame = 0;
if (!boxa1 || !boxa2)
return ERROR_INT("boxa1 and boxa2 not both defined", procName, 1);
n = boxaGetCount(boxa1);
if (n != boxaGetCount(boxa2))
return 0;
if ((countarray = (l_int32 *)LEPT_CALLOC(n, sizeof(l_int32))) == NULL)
return ERROR_INT("calloc fail for countarray", procName, 1);
na = numaMakeConstant(0.0, n);
for (i = 0; i < n; i++) {
box1 = boxaGetBox(boxa1, i, L_CLONE);
jstart = L_MAX(0, i - maxdist);
jend = L_MIN(n-1, i + maxdist);
found = FALSE;
for (j = jstart; j <= jend; j++) {
box2 = boxaGetBox(boxa2, j, L_CLONE);
boxEqual(box1, box2, &samebox);
if (samebox && countarray[j] == 0) {
countarray[j] = 1;
numaReplaceNumber(na, i, j);
found = TRUE;
boxDestroy(&box2);
break;
}
boxDestroy(&box2);
}
boxDestroy(&box1);
if (!found) {
numaDestroy(&na);
LEPT_FREE(countarray);
return 0;
}
}
*psame = 1;
if (pnaindex)
*pnaindex = na;
else
numaDestroy(&na);
LEPT_FREE(countarray);
return 0;
}
/*!
* \brief boxSimilar()
*
* \param[in] box1
* \param[in] box2
* \param[in] leftdiff, rightdiff, topdiff, botdiff
* \param[out] psimilar 1 if similar; 0 otherwise
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) The values of leftdiff (etc) are the maximum allowed deviations
* between the locations of the left (etc) sides. If any side
* pairs differ by more than this amount, the boxes are not similar.
*
*/
l_ok
boxSimilar(BOX *box1,
BOX *box2,
l_int32 leftdiff,
l_int32 rightdiff,
l_int32 topdiff,
l_int32 botdiff,
l_int32 *psimilar)
{
l_int32 l1, l2, r1, r2, t1, t2, b1, b2, valid1, valid2;
PROCNAME("boxSimilar");
if (!psimilar)
return ERROR_INT("&similar not defined", procName, 1);
*psimilar = 0;
if (!box1 || !box2)
return ERROR_INT("boxes not both defined", procName, 1);
boxIsValid(box1, &valid1);
boxIsValid(box2, &valid2);
if (!valid1 || !valid2)
return ERROR_INT("boxes not both valid", procName, 1);
boxGetSideLocations(box1, &l1, &r1, &t1, &b1);
boxGetSideLocations(box2, &l2, &r2, &t2, &b2);
if (L_ABS(l1 - l2) > leftdiff)
return 0;
if (L_ABS(r1 - r2) > rightdiff)
return 0;
if (L_ABS(t1 - t2) > topdiff)
return 0;
if (L_ABS(b1 - b2) > botdiff)
return 0;
*psimilar = 1;
return 0;
}
/*!
* \brief boxaSimilar()
*
* \param[in] boxa1
* \param[in] boxa2
* \param[in] leftdiff, rightdiff, topdiff, botdiff
* \param[in] debug output details of non-similar boxes
* \param[out] psimilar 1 if similar; 0 otherwise
* \param[out] pnasim [optional] na containing 1 if similar; else 0
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) See boxSimilar() for parameter usage.
* (2) Corresponding boxes are taken in order in the two boxa.
* (3) %nasim is an indicator array with a (0/1) for each box pair.
* (4) With %nasim or debug == 1, boxes continue to be tested
* after failure.
*
*/
l_ok
boxaSimilar(BOXA *boxa1,
BOXA *boxa2,
l_int32 leftdiff,
l_int32 rightdiff,
l_int32 topdiff,
l_int32 botdiff,
l_int32 debug,
l_int32 *psimilar,
NUMA **pnasim)
{
l_int32 i, n1, n2, match, mismatch;
BOX *box1, *box2;
PROCNAME("boxaSimilar");
if (psimilar) *psimilar = 0;
if (pnasim) *pnasim = NULL;
if (!boxa1 || !boxa2)
return ERROR_INT("boxa1 and boxa2 not both defined", procName, 1);
if (!psimilar)
return ERROR_INT("&similar not defined", procName, 1);
n1 = boxaGetCount(boxa1);
n2 = boxaGetCount(boxa2);
if (n1 != n2) {
L_ERROR("boxa counts differ: %d vs %d\n", procName, n1, n2);
return 1;
}
if (pnasim) *pnasim = numaCreate(n1);
mismatch = FALSE;
for (i = 0; i < n1; i++) {
box1 = boxaGetBox(boxa1, i, L_CLONE);
box2 = boxaGetBox(boxa2, i, L_CLONE);
boxSimilar(box1, box2, leftdiff, rightdiff, topdiff, botdiff,
&match);
boxDestroy(&box1);
boxDestroy(&box2);
if (pnasim)
numaAddNumber(*pnasim, match);
if (!match) {
mismatch = TRUE;
if (!debug && pnasim == NULL)
return 0;
else if (debug)
L_INFO("box %d not similar\n", procName, i);
}
}
if (!mismatch) *psimilar = 1;
return 0;
}
/*----------------------------------------------------------------------*
* Boxa combine and split *
*----------------------------------------------------------------------*/
/*!
* \brief boxaJoin()
*
* \param[in] boxad dest boxa; add to this one
* \param[in] boxas source boxa; add from this one
* \param[in] istart starting index in boxas
* \param[in] iend ending index in boxas; use -1 to cat all
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This appends a clone of each indicated box in boxas to boxad
* (2) istart < 0 is taken to mean 'read from the start' (istart = 0)
* (3) iend < 0 means 'read to the end'
* (4) if boxas == NULL or has no boxes, this is a no-op.
*
*/
l_ok
boxaJoin(BOXA *boxad,
BOXA *boxas,
l_int32 istart,
l_int32 iend)
{
l_int32 n, i;
BOX *box;
PROCNAME("boxaJoin");
if (!boxad)
return ERROR_INT("boxad not defined", procName, 1);
if (!boxas || ((n = boxaGetCount(boxas)) == 0))
return 0;
if (istart < 0)
istart = 0;
if (iend < 0 || iend >= n)
iend = n - 1;
if (istart > iend)
return ERROR_INT("istart > iend; nothing to add", procName, 1);
for (i = istart; i <= iend; i++) {
box = boxaGetBox(boxas, i, L_CLONE);
boxaAddBox(boxad, box, L_INSERT);
}
return 0;
}
/*!
* \brief boxaaJoin()
*
* \param[in] baad dest boxaa; add to this one
* \param[in] baas source boxaa; add from this one
* \param[in] istart starting index in baas
* \param[in] iend ending index in baas; use -1 to cat all
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) This appends a clone of each indicated boxa in baas to baad
* (2) istart < 0 is taken to mean 'read from the start' (istart = 0)
* (3) iend < 0 means 'read to the end'
* (4) if baas == NULL, this is a no-op.
*
*/
l_ok
boxaaJoin(BOXAA *baad,
BOXAA *baas,
l_int32 istart,
l_int32 iend)
{
l_int32 n, i;
BOXA *boxa;
PROCNAME("boxaaJoin");
if (!baad)
return ERROR_INT("baad not defined", procName, 1);
if (!baas)
return 0;
if (istart < 0)
istart = 0;
n = boxaaGetCount(baas);
if (iend < 0 || iend >= n)
iend = n - 1;
if (istart > iend)
return ERROR_INT("istart > iend; nothing to add", procName, 1);
for (i = istart; i <= iend; i++) {
boxa = boxaaGetBoxa(baas, i, L_CLONE);
boxaaAddBoxa(baad, boxa, L_INSERT);
}
return 0;
}
/*!
* \brief boxaSplitEvenOdd()
*
* \param[in] boxa
* \param[in] fillflag 1 to put invalid boxes in place; 0 to omit
* \param[out] pboxae, pboxao save even and odd boxes in their separate
* boxa, setting the other type to invalid boxes.
* \return 0 if OK, 1 on error
*
*
* Notes:
* (1) If %fillflag == 1, boxae has copies of the even boxes
* in their original location, and nvalid boxes are placed
* in the odd array locations. And v.v.
* (2) If %fillflag == 0, boxae has only copies of the even boxes.
*
*/
l_ok
boxaSplitEvenOdd(BOXA *boxa,
l_int32 fillflag,
BOXA **pboxae,
BOXA **pboxao)
{
l_int32 i, n;
BOX *box, *box1;
PROCNAME("boxaSplitEvenOdd");
if (pboxae) *pboxae = NULL;
if (pboxao) *pboxao = NULL;
if (!pboxae || !pboxao)
return ERROR_INT("&boxae and &boxao not both defined", procName, 1);
if (!boxa)
return ERROR_INT("boxa not defined", procName, 1);
n = boxaGetCount(boxa);
*pboxae = boxaCreate(n);
*pboxao = boxaCreate(n);
if (fillflag == 0) {
/* don't fill with invalid boxes; end up with half-size boxa */
for (i = 0; i < n; i++) {
box = boxaGetBox(boxa, i, L_COPY);
if ((i & 1) == 0)
boxaAddBox(*pboxae, box, L_INSERT);
else
boxaAddBox(*pboxao, box, L_INSERT);
}
} else {
for (i = 0; i < n; i++) {
box = boxaGetBox(boxa, i, L_COPY);
box1 = boxCreate(0, 0, 0, 0); /* empty placeholder */
if ((i & 1) == 0) {
boxaAddBox(*pboxae, box, L_INSERT);
boxaAddBox(*pboxao, box1, L_INSERT);
} else {
boxaAddBox(*pboxae, box1, L_INSERT);
boxaAddBox(*pboxao, box, L_INSERT);
}
}
}
return 0;
}
/*!
* \brief boxaMergeEvenOdd()
*
* \param[in] boxae boxes to go in even positions in merged boxa
* \param[in] boxao boxes to go in odd positions in merged boxa
* \param[in] fillflag 1 if there are invalid boxes in placeholders
* \return boxad merged, or NULL on error
*
*
* Notes:
* (1) This is essentially the inverse of boxaSplitEvenOdd().
* Typically, boxae and boxao were generated by boxaSplitEvenOdd(),
* and the value of %fillflag needs to be the same in both calls.
* (2) If %fillflag == 1, both boxae and boxao are of the same size;
* otherwise boxae may have one more box than boxao.
*
*/
BOXA *
boxaMergeEvenOdd(BOXA *boxae,
BOXA *boxao,
l_int32 fillflag)
{
l_int32 i, n, ne, no;
BOX *box;
BOXA *boxad;
PROCNAME("boxaMergeEvenOdd");
if (!boxae || !boxao)
return (BOXA *)ERROR_PTR("boxae and boxao not defined", procName, NULL);
ne = boxaGetCount(boxae);
no = boxaGetCount(boxao);
if (ne < no || ne > no + 1)
return (BOXA *)ERROR_PTR("boxa sizes invalid", procName, NULL);
boxad = boxaCreate(ne);
if (fillflag == 0) { /* both are approx. half-sized; all valid boxes */
n = ne + no;
for (i = 0; i < n; i++) {
if ((i & 1) == 0)
box = boxaGetBox(boxae, i / 2, L_COPY);
else
box = boxaGetBox(boxao, i / 2, L_COPY);
boxaAddBox(boxad, box, L_INSERT);
}
} else { /* both are full size and have invalid placeholders */
for (i = 0; i < ne; i++) {
if ((i & 1) == 0)
box = boxaGetBox(boxae, i, L_COPY);
else
box = boxaGetBox(boxao, i, L_COPY);
boxaAddBox(boxad, box, L_INSERT);
}
}
return boxad;
}