/*!
* \brief pixCountConnComp()
*
* \param[in] pixs 1 bpp
* \param[in] connectivity 4 or 8
* \param[out] pcount
* \return 0 if OK, 1 on error
*
* Notes:
* (1 This is the top-level call for getting the number of
* 4- or 8-connected components in a 1 bpp image.
* 2 It works on a copy of the input pix. The c.c. are located
* in raster order and erased one at a time.
*/
l_int32
pixCountConnComp(PIX *pixs,
l_int32 connectivity,
l_int32 *pcount)
{
l_int32 h, iszero;
l_int32 x, y, xstart, ystart;
PIX *pixt;
L_STACK *stack, *auxstack;
PROCNAME("pixCountConnComp");
if (!pcount)
return ERROR_INT("&count not defined", procName, 1);
*pcount = 0; /* initialize the count to 0 */
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
if (connectivity != 4 && connectivity != 8)
return ERROR_INT("connectivity not 4 or 8", procName, 1);
pixt = NULL;
stack = NULL;
pixZero(pixs, &iszero);
if (iszero)
return 0;
if ((pixt = pixCopy(NULL, pixs)) == NULL)
return ERROR_INT("pixt not made", procName, 1);
h = pixGetHeight(pixs);
if ((stack = lstackCreate(h)) == NULL) {
L_ERROR("stack not made\n", procName);
goto cleanup;
}
auxstack = lstackCreate(0);
stack->auxstack = auxstack;
xstart = 0;
ystart = 0;
while (1) {
if (!nextOnPixelInRaster(pixt, xstart, ystart, &x, &y))
break;
pixSeedfill(pixt, stack, x, y, connectivity);
(*pcount)++;
xstart = x;
ystart = y;
}
/* Cleanup, freeing the fillsegs on each stack */
cleanup:
lstackDestroy(&stack, TRUE);
pixDestroy(&pixt);
return 0;
}
/*!
* \brief pixSeedfill8()
*
* \param[in] pixs 1 bpp
* \param[in] stack for holding fillsegs
* \param[in] x,y location of seed pixel
* \return 0 if OK, 1 on error
*
* <pre>
* Notes:
* (1) This is Paul Heckbert's stack-based 8-cc seedfill algorithm.
* (2) This operates on the input 1 bpp pix to remove the fg seed
* pixel, at (x,y), and all pixels that are 8-connected to it.
* The seed pixel at (x,y) must initially be ON.
* (3) Reference: see pixSeedFill8BB()
* </pre>
*/
l_int32
pixSeedfill8(PIX *pixs,
L_STACK *stack,
l_int32 x,
l_int32 y)
{
l_int32 w, h, xstart, wpl, x1, x2, dy;
l_int32 xmax, ymax;
l_uint32 *data, *line;
PROCNAME("pixSeedfill8");
if (!pixs || pixGetDepth(pixs) != 1)
return ERROR_INT("pixs not defined or not 1 bpp", procName, 1);
if (!stack)
return ERROR_INT("stack not defined", procName, 1);
if (!stack->auxstack)
stack->auxstack = lstackCreate(0);
pixGetDimensions(pixs, &w, &h, NULL);
xmax = w - 1;
ymax = h - 1;
data = pixGetData(pixs);
wpl = pixGetWpl(pixs);
line = data + y * wpl;
/* Check pix value of seed; must be ON */
if (x < 0 || x > xmax || y < 0 || y > ymax || (GET_DATA_BIT(line, x) == 0))
return 0;
/* Init stack to seed */
pushFillseg(stack, x, x, y, 1, ymax);
pushFillseg(stack, x, x, y + 1, -1, ymax);
while (lstackGetCount(stack) > 0) {
/* Pop segment off stack and fill a neighboring scan line */
popFillseg(stack, &x1, &x2, &y, &dy);
line = data + y * wpl;
/* A segment of scanline y - dy for x1 <= x <= x2 was
* previously filled. We now explore adjacent pixels
* in scan line y. There are three regions: to the
* left of x1, between x1 and x2, and to the right of x2.
* These regions are handled differently. Leaks are
* possible expansions beyond the previous segment and
* going back in the -dy direction. These can happen
* for x < x1 and for x > x2. Any "leak" segments
* are plugged with a push in the -dy (opposite) direction.
* And any segments found anywhere are always extended
* in the +dy direction. */
for (x = x1 - 1; x >= 0 && (GET_DATA_BIT(line, x) == 1); x--)
CLEAR_DATA_BIT(line,x);
if (x >= x1 - 1) /* pix at x1 - 1 was off and was not cleared */
goto skip;
xstart = x + 1;
if (xstart < x1) /* leak on left? */
pushFillseg(stack, xstart, x1 - 1, y, -dy, ymax);
x = x1;
do {
for (; x <= xmax && (GET_DATA_BIT(line, x) == 1); x++)
CLEAR_DATA_BIT(line, x);
pushFillseg(stack, xstart, x - 1, y, dy, ymax);
if (x > x2) /* leak on right? */
pushFillseg(stack, x2 + 1, x - 1, y, -dy, ymax);
skip:
for (x++; x <= x2 + 1 &&
x <= xmax &&
(GET_DATA_BIT(line, x) == 0); x++)
;
xstart = x;
} while (x <= x2 + 1 && x <= xmax);
}
return 0;
}
/*!
* \brief pixSeedfill8BB()
*
* \param[in] pixs 1 bpp
* \param[in] stack for holding fillsegs
* \param[in] x,y location of seed pixel
* \return box or NULL on error.
*
* <pre>
* Notes:
* (1) This is Paul Heckbert's stack-based 8-cc seedfill algorithm.
* (2) This operates on the input 1 bpp pix to remove the fg seed
* pixel, at (x,y), and all pixels that are 8-connected to it.
* The seed pixel at (x,y) must initially be ON.
* (3) Returns the bounding box of the erased 8-cc component.
* (4) Reference: see Paul Heckbert's stack-based seed fill algorithm
* in "Graphic Gems", ed. Andrew Glassner, Academic
* Press, 1990. The algorithm description is given
* on pp. 275-277; working C code is on pp. 721-722.)
* The code here follows Heckbert's closely, except
* the leak checks are changed for 8 connectivity.
* See comments on pixSeedfill4BB() for more details.
* </pre>
*/
BOX *
pixSeedfill8BB(PIX *pixs,
L_STACK *stack,
l_int32 x,
l_int32 y)
{
l_int32 w, h, xstart, wpl, x1, x2, dy;
l_int32 xmax, ymax;
l_int32 minx, maxx, miny, maxy; /* for bounding box of this c.c. */
l_uint32 *data, *line;
BOX *box;
PROCNAME("pixSeedfill8BB");
if (!pixs || pixGetDepth(pixs) != 1)
return (BOX *)ERROR_PTR("pixs undefined or not 1 bpp", procName, NULL);
if (!stack)
return (BOX *)ERROR_PTR("stack not defined", procName, NULL);
if (!stack->auxstack)
stack->auxstack = lstackCreate(0);
pixGetDimensions(pixs, &w, &h, NULL);
xmax = w - 1;
ymax = h - 1;
data = pixGetData(pixs);
wpl = pixGetWpl(pixs);
line = data + y * wpl;
/* Check pix value of seed; must be ON */
if (x < 0 || x > xmax || y < 0 || y > ymax || (GET_DATA_BIT(line, x) == 0))
return NULL;
/* Init stack to seed:
* Must first init b.b. values to prevent valgrind from complaining;
* then init b.b. boundaries correctly to seed. */
minx = miny = 100000;
maxx = maxy = 0;
pushFillsegBB(stack, x, x, y, 1, ymax, &minx, &maxx, &miny, &maxy);
pushFillsegBB(stack, x, x, y + 1, -1, ymax, &minx, &maxx, &miny, &maxy);
minx = maxx = x;
miny = maxy = y;
while (lstackGetCount(stack) > 0) {
/* Pop segment off stack and fill a neighboring scan line */
popFillseg(stack, &x1, &x2, &y, &dy);
line = data + y * wpl;
/* A segment of scanline y - dy for x1 <= x <= x2 was
* previously filled. We now explore adjacent pixels
* in scan line y. There are three regions: to the
* left of x1, between x1 and x2, and to the right of x2.
* These regions are handled differently. Leaks are
* possible expansions beyond the previous segment and
* going back in the -dy direction. These can happen
* for x < x1 and for x > x2. Any "leak" segments
* are plugged with a push in the -dy (opposite) direction.
* And any segments found anywhere are always extended
* in the +dy direction. */
for (x = x1 - 1; x >= 0 && (GET_DATA_BIT(line, x) == 1); x--)
CLEAR_DATA_BIT(line,x);
if (x >= x1 - 1) /* pix at x1 - 1 was off and was not cleared */
goto skip;
xstart = x + 1;
if (xstart < x1) /* leak on left? */
pushFillsegBB(stack, xstart, x1 - 1, y, -dy,
ymax, &minx, &maxx, &miny, &maxy);
x = x1;
do {
for (; x <= xmax && (GET_DATA_BIT(line, x) == 1); x++)
CLEAR_DATA_BIT(line, x);
pushFillsegBB(stack, xstart, x - 1, y, dy,
ymax, &minx, &maxx, &miny, &maxy);
if (x > x2) /* leak on right? */
pushFillsegBB(stack, x2 + 1, x - 1, y, -dy,
ymax, &minx, &maxx, &miny, &maxy);
skip:
for (x++; x <= x2 + 1 &&
x <= xmax &&
(GET_DATA_BIT(line, x) == 0); x++)
;
xstart = x;
} while (x <= x2 + 1 && x <= xmax);
}
if ((box = boxCreate(minx, miny, maxx - minx + 1, maxy - miny + 1))
== NULL)
return (BOX *)ERROR_PTR("box not made", procName, NULL);
return box;
}
/*!
* \brief pixConnCompBB()
*
* \param[in] pixs 1 bpp
* \param[in] connectivity 4 or 8
* \return boxa, or NULL on error
*
* <pre>
* Notes:
* (1) Finds bounding boxes of 4- or 8-connected components
* in a binary image.
* (2) This works on a copy of the input pix. The c.c. are located
* in raster order and erased one at a time. In the process,
* the b.b. is computed and saved.
* </pre>
*/
BOXA *
pixConnCompBB(PIX *pixs,
l_int32 connectivity)
{
l_int32 h, iszero;
l_int32 x, y, xstart, ystart;
PIX *pixt;
BOX *box;
BOXA *boxa;
L_STACK *stack, *auxstack;
PROCNAME("pixConnCompBB");
if (!pixs || pixGetDepth(pixs) != 1)
return (BOXA *)ERROR_PTR("pixs undefined or not 1 bpp", procName, NULL);
if (connectivity != 4 && connectivity != 8)
return (BOXA *)ERROR_PTR("connectivity not 4 or 8", procName, NULL);
boxa = NULL;
pixt = NULL;
stack = NULL;
pixZero(pixs, &iszero);
if (iszero)
return boxaCreate(1); /* return empty boxa */
if ((pixt = pixCopy(NULL, pixs)) == NULL)
return (BOXA *)ERROR_PTR("pixt not made", procName, NULL);
h = pixGetHeight(pixs);
if ((stack = lstackCreate(h)) == NULL) {
L_ERROR("stack not made\n", procName);
goto cleanup;
}
auxstack = lstackCreate(0);
stack->auxstack = auxstack;
boxa = boxaCreate(0);
xstart = 0;
ystart = 0;
while (1) {
if (!nextOnPixelInRaster(pixt, xstart, ystart, &x, &y))
break;
if ((box = pixSeedfillBB(pixt, stack, x, y, connectivity)) == NULL) {
L_ERROR("box not made\n", procName);
boxaDestroy(&boxa);
goto cleanup;
}
boxaAddBox(boxa, box, L_INSERT);
xstart = x;
ystart = y;
}
#if DEBUG
pixCountPixels(pixt, &iszero, NULL);
fprintf(stderr, "Number of remaining pixels = %d\n", iszero);
pixWrite("junkremain", pixt1, IFF_PNG);
#endif /* DEBUG */
/* Cleanup, freeing the fillsegs on each stack */
cleanup:
lstackDestroy(&stack, TRUE);
pixDestroy(&pixt);
return boxa;
}
/*!
* \brief pixConnCompPixa()
*
* \param[in] pixs 1 bpp
* \param[out] ppixa pixa of each c.c.
* \param[in] connectivity 4 or 8
* \return boxa, or NULL on error
*
* <pre>
* Notes:
* (1) This finds bounding boxes of 4- or 8-connected components
* in a binary image, and saves images of each c.c
* in a pixa array.
* (2) It sets up 2 temporary pix, and for each c.c. that is
* located in raster order, it erases the c.c. from one pix,
* then uses the b.b. to extract the c.c. from the two pix using
* an XOR, and finally erases the c.c. from the second pix.
* (3) A clone of the returned boxa (where all boxes in the array
* are clones) is inserted into the pixa.
* (4) If the input is valid, this always returns a boxa and a pixa.
* If pixs is empty, the boxa and pixa will be empty.
* </pre>
*/
BOXA *
pixConnCompPixa(PIX *pixs,
PIXA **ppixa,
l_int32 connectivity)
{
l_int32 h, iszero;
l_int32 x, y, xstart, ystart;
PIX *pix1, *pix2, *pix3, *pix4;
PIXA *pixa;
BOX *box;
BOXA *boxa;
L_STACK *stack, *auxstack;
PROCNAME("pixConnCompPixa");
if (!ppixa)
return (BOXA *)ERROR_PTR("&pixa not defined", procName, NULL);
*ppixa = NULL;
if (!pixs || pixGetDepth(pixs) != 1)
return (BOXA *)ERROR_PTR("pixs undefined or not 1 bpp", procName, NULL);
if (connectivity != 4 && connectivity != 8)
return (BOXA *)ERROR_PTR("connectivity not 4 or 8", procName, NULL);
boxa = NULL;
pix1 = pix2 = pix3 = pix4 = NULL;
stack = NULL;
pixZero(pixs, &iszero);
if (iszero)
return boxaCreate(1); /* return empty boxa */
pix1 = pixCopy(NULL, pixs);
pix2 = pixCopy(NULL, pixs);
if (!pix1 || !pix2) {
L_ERROR("pix1 or pix2 not made\n", procName);
goto cleanup;
}
h = pixGetHeight(pixs);
if ((stack = lstackCreate(h)) == NULL) {
L_ERROR("stack not made\n", procName);
goto cleanup;
}
auxstack = lstackCreate(0);
stack->auxstack = auxstack;
pixa = pixaCreate(0);
boxa = boxaCreate(0);
xstart = 0;
ystart = 0;
while (1) {
if (!nextOnPixelInRaster(pix1, xstart, ystart, &x, &y))
break;
if ((box = pixSeedfillBB(pix1, stack, x, y, connectivity)) == NULL) {
L_ERROR("box not made\n", procName);
pixaDestroy(&pixa);
boxaDestroy(&boxa);
goto cleanup;
}
boxaAddBox(boxa, box, L_INSERT);
/* Save the c.c. and remove from pix2 as well */
pix3 = pixClipRectangle(pix1, box, NULL);
pix4 = pixClipRectangle(pix2, box, NULL);
pixXor(pix3, pix3, pix4);
pixRasterop(pix2, box->x, box->y, box->w, box->h, PIX_SRC ^ PIX_DST,
pix3, 0, 0);
pixaAddPix(pixa, pix3, L_INSERT);
pixDestroy(&pix4);
xstart = x;
ystart = y;
}
#if DEBUG
pixCountPixels(pix1, &iszero, NULL);
fprintf(stderr, "Number of remaining pixels = %d\n", iszero);
pixWrite("junkremain", pix1, IFF_PNG);
#endif /* DEBUG */
/* Remove old boxa of pixa and replace with a clone copy */
boxaDestroy(&pixa->boxa);
pixa->boxa = boxaCopy(boxa, L_CLONE);
*ppixa = pixa;
/* Cleanup, freeing the fillsegs on each stack */
cleanup:
lstackDestroy(&stack, TRUE);
pixDestroy(&pix1);
pixDestroy(&pix2);
return boxa;
}
/*!
* identifyWatershedBasin()
*
* Input: wshed
* index (index of basin to be located)
* level (of basin at point at which the two basins met)
* &box (<return> bounding box of basin)
* &pixd (<return> pix of basin, cropped to its bounding box)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) This is a static function, so we assume pixlab, pixs and pixt
* exist and are the same size.
* (2) It selects all pixels that have the label @index in pixlab
* and that have a value in pixs that is less than @level.
* (3) It is used whenever two seeded basins meet (typically at a saddle),
* or when one seeded basin meets a 'filler'. All identified
* basins are saved as a watershed.
*/
static l_int32
identifyWatershedBasin(L_WSHED *wshed,
l_int32 index,
l_int32 level,
BOX **pbox,
PIX **ppixd) {
l_int32 imin, imax, jmin, jmax, minx, miny, maxx, maxy;
l_int32 bw, bh, i, j, w, h, x, y;
l_int32 *lut;
l_uint32 label, bval, lval;
void **lines8, **linelab32, **linet1;
BOX *box;
PIX *pixs, *pixt, *pixd;
L_QUEUE *lq;
PROCNAME("identifyWatershedBasin");
if (!pbox)
return ERROR_INT("&box not defined", procName, 1);
*pbox = NULL;
if (!ppixd)
return ERROR_INT("&pixd not defined", procName, 1);
*ppixd = NULL;
if (!wshed)
return ERROR_INT("wshed not defined", procName, 1);
/* Make a queue and an auxiliary stack */
lq = lqueueCreate(0);
lq->stack = lstackCreate(0);
pixs = wshed->pixs;
pixt = wshed->pixt;
lines8 = wshed->lines8;
linelab32 = wshed->linelab32;
linet1 = wshed->linet1;
lut = wshed->lut;
pixGetDimensions(pixs, &w, &h, NULL);
/* Prime the queue with the seed pixel for this watershed. */
minx = miny = 1000000;
maxx = maxy = 0;
ptaGetIPt(wshed->ptas, index, &x, &y);
pixSetPixel(pixt, x, y, 1);
pushNewPixel(lq, x, y, &minx, &maxx, &miny, &maxy);
if (wshed->debug) fprintf(stderr, "prime: (x,y) = (%d, %d)\n", x, y);
/* Each pixel in a spreading breadth-first search is inspected.
* It is accepted as part of this watershed, and pushed on
* the search queue, if:
* (1) It has a label value equal to @index
* (2) The pixel value is less than @level, the overflow
* height at which the two basins join.
* (3) It has not yet been seen in this search. */
while (lqueueGetCount(lq) > 0) {
popNewPixel(lq, &x, &y);
imin = L_MAX(0, y - 1);
imax = L_MIN(h - 1, y + 1);
jmin = L_MAX(0, x - 1);
jmax = L_MIN(w - 1, x + 1);
for (i = imin; i <= imax; i++) {
for (j = jmin; j <= jmax; j++) {
if (j == x && i == y) continue; /* parent */
label = GET_DATA_FOUR_BYTES(linelab32[i], j);
if (label == MAX_LABEL_VALUE || lut[label] != index) continue;
bval = GET_DATA_BIT(linet1[i], j);
if (bval == 1) continue; /* already seen */
lval = GET_DATA_BYTE(lines8[i], j);
if (lval >= level) continue; /* too high */
SET_DATA_BIT(linet1[i], j);
pushNewPixel(lq, j, i, &minx, &maxx, &miny, &maxy);
}
}
}
/* Extract the box and pix, and clear pixt */
bw = maxx - minx + 1;
bh = maxy - miny + 1;
box = boxCreate(minx, miny, bw, bh);
pixd = pixClipRectangle(pixt, box, NULL);
pixRasterop(pixt, minx, miny, bw, bh, PIX_SRC ^ PIX_DST, pixd, 0, 0);
*pbox = box;
*ppixd = pixd;
lqueueDestroy(&lq, 1);
return 0;
}
/*!
* wshedApply()
*
* Input: wshed (generated from wshedCreate())
* Return: 0 if OK, 1 on error
*
* Iportant note:
* (1) This is buggy. It seems to locate watersheds that are
* duplicates. The watershed extraction after complete fill
* grabs some regions belonging to existing watersheds.
* See prog/watershedtest.c for testing.
*/
l_int32
wshedApply(L_WSHED *wshed) {
char two_new_watersheds[] = "Two new watersheds";
char seed_absorbed_into_seeded_basin[] = "Seed absorbed into seeded basin";
char one_new_watershed_label[] = "One new watershed (label)";
char one_new_watershed_index[] = "One new watershed (index)";
char minima_absorbed_into_seeded_basin[] =
"Minima absorbed into seeded basin";
char minima_absorbed_by_filler_or_another[] =
"Minima absorbed by filler or another";
l_int32 nseeds, nother, nboth, arraysize;
l_int32 i, j, val, x, y, w, h, index, mindepth;
l_int32 imin, imax, jmin, jmax, cindex, clabel, nindex;
l_int32 hindex, hlabel, hmin, hmax, minhindex, maxhindex;
l_int32 *lut;
l_uint32 ulabel, uval;
void **lines8, **linelab32;
NUMA *nalut, *nalevels, *nash, *namh, *nasi;
NUMA **links;
L_HEAP *lh;
PIX *pixmin, *pixsd;
PIXA *pixad;
L_STACK *rstack;
PTA *ptas, *ptao;
PROCNAME("wshedApply");
if (!wshed)
return ERROR_INT("wshed not defined", procName, 1);
/* ------------------------------------------------------------ *
* Initialize priority queue and pixlab with seeds and minima *
* ------------------------------------------------------------ */
lh = lheapCreate(0, L_SORT_INCREASING); /* remove lowest values first */
rstack = lstackCreate(0); /* for reusing the WSPixels */
pixGetDimensions(wshed->pixs, &w, &h, NULL);
lines8 = wshed->lines8; /* wshed owns this */
linelab32 = wshed->linelab32; /* ditto */
/* Identify seed (marker) pixels, 1 for each c.c. in pixm */
pixSelectMinInConnComp(wshed->pixs, wshed->pixm, &ptas, &nash);
pixsd = pixGenerateFromPta(ptas, w, h);
nseeds = ptaGetCount(ptas);
for (i = 0; i < nseeds; i++) {
ptaGetIPt(ptas, i, &x, &y);
uval = GET_DATA_BYTE(lines8[y], x);
pushWSPixel(lh, rstack, (l_int32) uval, x, y, i);
}
wshed->ptas = ptas;
nasi = numaMakeConstant(1, nseeds); /* indicator array */
wshed->nasi = nasi;
wshed->nash = nash;
wshed->nseeds = nseeds;
/* Identify minima that are not seeds. Use these 4 steps:
* (1) Get the local minima, which can have components
* of arbitrary size. This will be a clipping mask.
* (2) Get the image of the actual seeds (pixsd)
* (3) Remove all elements of the clipping mask that have a seed.
* (4) Shrink each of the remaining elements of the minima mask
* to a single pixel. */
pixLocalExtrema(wshed->pixs, 200, 0, &pixmin, NULL);
pixRemoveSeededComponents(pixmin, pixsd, pixmin, 8, 2);
pixSelectMinInConnComp(wshed->pixs, pixmin, &ptao, &namh);
nother = ptaGetCount(ptao);
for (i = 0; i < nother; i++) {
ptaGetIPt(ptao, i, &x, &y);
uval = GET_DATA_BYTE(lines8[y], x);
pushWSPixel(lh, rstack, (l_int32) uval, x, y, nseeds + i);
}
wshed->namh = namh;
/* ------------------------------------------------------------ *
* Initialize merging lookup tables *
* ------------------------------------------------------------ */
/* nalut should always give the current after-merging index.
* links are effectively backpointers: they are numas associated with
* a dest index of all indices in nalut that point to that index. */
mindepth = wshed->mindepth;
nboth = nseeds + nother;
arraysize = 2 * nboth;
wshed->arraysize = arraysize;
nalut = numaMakeSequence(0, 1, arraysize);
lut = numaGetIArray(nalut);
wshed->lut = lut; /* wshed owns this */
links = (NUMA **) CALLOC(arraysize, sizeof(NUMA * ));
wshed->links = links; /* wshed owns this */
nindex = nseeds + nother; /* the next unused index value */
/* ------------------------------------------------------------ *
* Fill the basins, using the priority queue *
* ------------------------------------------------------------ */
pixad = pixaCreate(nseeds);
wshed->pixad = pixad; /* wshed owns this */
nalevels = numaCreate(nseeds);
wshed->nalevels = nalevels; /* wshed owns this */
L_INFO("nseeds = %d, nother = %d\n", procName, nseeds, nother);
while (lheapGetCount(lh) > 0) {
popWSPixel(lh, rstack, &val, &x, &y, &index);
/* fprintf(stderr, "x = %d, y = %d, index = %d\n", x, y, index); */
ulabel = GET_DATA_FOUR_BYTES(linelab32[y], x);
if (ulabel == MAX_LABEL_VALUE)
clabel = ulabel;
else
clabel = lut[ulabel];
cindex = lut[index];
if (clabel == cindex) continue; /* have already seen this one */
if (clabel == MAX_LABEL_VALUE) { /* new one; assign index and try to
* propagate to all neighbors */
SET_DATA_FOUR_BYTES(linelab32[y], x, cindex);
imin = L_MAX(0, y - 1);
imax = L_MIN(h - 1, y + 1);
jmin = L_MAX(0, x - 1);
jmax = L_MIN(w - 1, x + 1);
for (i = imin; i <= imax; i++) {
for (j = jmin; j <= jmax; j++) {
if (i == y && j == x) continue;
uval = GET_DATA_BYTE(lines8[i], j);
pushWSPixel(lh, rstack, (l_int32) uval, j, i, cindex);
}
}
} else { /* pixel is already labeled (differently); must resolve */
/* If both indices are seeds, check if the min height is
* greater than mindepth. If so, we have two new watersheds;
* locate them and assign to both regions a new index
* for further waterfill. If not, absorb the shallower
* watershed into the deeper one and continue filling it. */
pixGetPixel(pixsd, x, y, &uval);
if (clabel < nseeds && cindex < nseeds) {
wshedGetHeight(wshed, val, clabel, &hlabel);
wshedGetHeight(wshed, val, cindex, &hindex);
hmin = L_MIN(hlabel, hindex);
hmax = L_MAX(hlabel, hindex);
if (hmin == hmax) {
hmin = hlabel;
hmax = hindex;
}
if (wshed->debug) {
fprintf(stderr, "clabel,hlabel = %d,%d\n", clabel, hlabel);
fprintf(stderr, "hmin = %d, hmax = %d\n", hmin, hmax);
fprintf(stderr, "cindex,hindex = %d,%d\n", cindex, hindex);
if (hmin < mindepth)
fprintf(stderr, "Too shallow!\n");
}
if (hmin >= mindepth) {
debugWshedMerge(wshed, two_new_watersheds,
x, y, clabel, cindex);
wshedSaveBasin(wshed, cindex, val - 1);
wshedSaveBasin(wshed, clabel, val - 1);
numaSetValue(nasi, cindex, 0);
numaSetValue(nasi, clabel, 0);
if (wshed->debug) fprintf(stderr, "nindex = %d\n", nindex);
debugPrintLUT(lut, nindex, wshed->debug);
mergeLookup(wshed, clabel, nindex);
debugPrintLUT(lut, nindex, wshed->debug);
mergeLookup(wshed, cindex, nindex);
debugPrintLUT(lut, nindex, wshed->debug);
nindex++;
} else /* extraneous seed within seeded basin; absorb */ {
debugWshedMerge(wshed, seed_absorbed_into_seeded_basin,
x, y, clabel, cindex);
}
maxhindex = clabel; /* TODO: is this part of above 'else'? */
minhindex = cindex;
if (hindex > hlabel) {
maxhindex = cindex;
minhindex = clabel;
}
mergeLookup(wshed, minhindex, maxhindex);
} else if (clabel < nseeds && cindex >= nboth) {
/* If one index is a seed and the other is a merge of
* 2 watersheds, generate a single watershed. */
debugWshedMerge(wshed, one_new_watershed_label,
x, y, clabel, cindex);
wshedSaveBasin(wshed, clabel, val - 1);
numaSetValue(nasi, clabel, 0);
mergeLookup(wshed, clabel, cindex);
} else if (cindex < nseeds && clabel >= nboth) {
debugWshedMerge(wshed, one_new_watershed_index,
x, y, clabel, cindex);
wshedSaveBasin(wshed, cindex, val - 1);
numaSetValue(nasi, cindex, 0);
mergeLookup(wshed, cindex, clabel);
} else if (clabel < nseeds) { /* cindex from minima; absorb */
/* If one index is a seed and the other is from a minimum,
* merge the minimum wshed into the seed wshed. */
debugWshedMerge(wshed, minima_absorbed_into_seeded_basin,
x, y, clabel, cindex);
mergeLookup(wshed, cindex, clabel);
} else if (cindex < nseeds) { /* clabel from minima; absorb */
debugWshedMerge(wshed, minima_absorbed_into_seeded_basin,
x, y, clabel, cindex);
mergeLookup(wshed, clabel, cindex);
} else { /* If neither index is a seed, just merge */
debugWshedMerge(wshed, minima_absorbed_by_filler_or_another,
x, y, clabel, cindex);
mergeLookup(wshed, clabel, cindex);
}
}
}
#if 0
/* Use the indicator array to save any watersheds that fill
* to the maximum value. This seems to screw things up! */
for (i = 0; i < nseeds; i++) {
numaGetIValue(nasi, i, &ival);
if (ival == 1) {
wshedSaveBasin(wshed, lut[i], val - 1);
numaSetValue(nasi, i, 0);
}
}
#endif
numaDestroy(&nalut);
pixDestroy(&pixmin);
pixDestroy(&pixsd);
ptaDestroy(&ptao);
lheapDestroy(&lh, TRUE);
lstackDestroy(&rstack, TRUE);
return 0;
}
