/*!
* \brief boxaConvertToPta()
*
* \param[in] boxa
* \param[in] ncorners 2 or 4 for the representation of each box
* \return pta with %ncorners points for each box in the boxa,
* or NULL on error
*
* <pre>
* Notes:
* (1) If ncorners == 2, we select the UL and LR corners.
* Otherwise we save all 4 corners in this order: UL, UR, LL, LR.
* (2) Other boxa --> pta functions are:
* * boxaExtractAsPta(): allows extraction of any dimension
* and/or side location, with each in a separate pta.
* * boxaExtractCorners(): extracts any of the four corners as a pta.
* </pre>
*/
PTA *
boxaConvertToPta(BOXA *boxa,
l_int32 ncorners)
{
l_int32 i, n;
BOX *box;
PTA *pta, *pta1;
PROCNAME("boxaConvertToPta");
if (!boxa)
return (PTA *)ERROR_PTR("boxa not defined", procName, NULL);
if (ncorners != 2 && ncorners != 4)
return (PTA *)ERROR_PTR("ncorners not 2 or 4", procName, NULL);
n = boxaGetCount(boxa);
if ((pta = ptaCreate(n)) == NULL)
return (PTA *)ERROR_PTR("pta not made", procName, NULL);
for (i = 0; i < n; i++) {
box = boxaGetBox(boxa, i, L_COPY);
pta1 = boxConvertToPta(box, ncorners);
ptaJoin(pta, pta1, 0, -1);
boxDestroy(&box);
ptaDestroy(&pta1);
}
return pta;
}
/*!
* boxaApplyDisparity()
*
* Input: dew
* boxa
* direction (L_HORIZ or L_VERT)
* mapdir (1 if mapping forward from original to dewarped;
* 0 if backward)
* Return: boxad (modified by the disparity), or null on error
*/
static BOXA *
boxaApplyDisparity(L_DEWARP *dew,
BOXA *boxa,
l_int32 direction,
l_int32 mapdir)
{
l_int32 x, y, w, h, ib, ip, nbox, wpl;
l_float32 xn, yn;
l_float32 *data, *line;
BOX *boxs, *boxd;
BOXA *boxad;
FPIX *fpix;
PTA *ptas, *ptad;
PROCNAME("boxaApplyDisparity");
if (!dew)
return (BOXA *)ERROR_PTR("dew not defined", procName, NULL);
if (!boxa)
return (BOXA *)ERROR_PTR("boxa not defined", procName, NULL);
if (direction == L_VERT)
fpix = dew->fullvdispar;
else if (direction == L_HORIZ)
fpix = dew->fullhdispar;
else
return (BOXA *)ERROR_PTR("invalid direction", procName, NULL);
if (!fpix)
return (BOXA *)ERROR_PTR("full disparity not defined", procName, NULL);
fpixGetDimensions(fpix, &w, &h);
/* Clip the output to the positive quadrant because all box
* coordinates must be non-negative. */
data = fpixGetData(fpix);
wpl = fpixGetWpl(fpix);
nbox = boxaGetCount(boxa);
boxad = boxaCreate(nbox);
for (ib = 0; ib < nbox; ib++) {
boxs = boxaGetBox(boxa, ib, L_COPY);
ptas = boxConvertToPta(boxs, 4);
ptad = ptaCreate(4);
for (ip = 0; ip < 4; ip++) {
ptaGetIPt(ptas, ip, &x, &y);
line = data + y * wpl;
if (direction == L_VERT) {
if (mapdir == 0)
yn = y - line[x];
else
yn = y + line[x];
yn = L_MAX(0, yn);
ptaAddPt(ptad, x, yn);
} else { /* direction == L_HORIZ */
if (mapdir == 0)
xn = x - line[x];
else
xn = x + line[x];
xn = L_MAX(0, xn);
ptaAddPt(ptad, xn, y);
}
}
boxd = ptaConvertToBox(ptad);
boxaAddBox(boxad, boxd, L_INSERT);
boxDestroy(&boxs);
ptaDestroy(&ptas);
ptaDestroy(&ptad);
}
return boxad;
}
