/*!
* \brief pixQuadtreeMean()
*
* \param[in] pixs 8 bpp, no colormap
* \param[in] nlevels in quadtree; max allowed depends on image size
* \param[in] *pix_ma input mean accumulator; can be null
* \param[out] *pfpixa mean values in quadtree
* \return 0 if OK, 1 on error
*
* <pre>
* Notes:
* (1) The returned fpixa has %nlevels of fpix, each containing
* the mean values at its level. Level 0 has a
* single value; level 1 has 4 values; level 2 has 16; etc.
* </pre>
*/
l_int32
pixQuadtreeMean(PIX *pixs,
l_int32 nlevels,
PIX *pix_ma,
FPIXA **pfpixa)
{
l_int32 i, j, w, h, size, n;
l_float32 val;
BOX *box;
BOXA *boxa;
BOXAA *baa;
FPIX *fpix;
PIX *pix_mac;
PROCNAME("pixQuadtreeMean");
if (!pfpixa)
return ERROR_INT("&fpixa not defined", procName, 1);
*pfpixa = NULL;
if (!pixs || pixGetDepth(pixs) != 8)
return ERROR_INT("pixs not defined or not 8 bpp", procName, 1);
pixGetDimensions(pixs, &w, &h, NULL);
if (nlevels > quadtreeMaxLevels(w, h))
return ERROR_INT("nlevels too large for image", procName, 1);
if (!pix_ma)
pix_mac = pixBlockconvAccum(pixs);
else
pix_mac = pixClone(pix_ma);
if (!pix_mac)
return ERROR_INT("pix_mac not made", procName, 1);
if ((baa = boxaaQuadtreeRegions(w, h, nlevels)) == NULL) {
pixDestroy(&pix_mac);
return ERROR_INT("baa not made", procName, 1);
}
*pfpixa = fpixaCreate(nlevels);
for (i = 0; i < nlevels; i++) {
boxa = boxaaGetBoxa(baa, i, L_CLONE);
size = 1 << i;
n = boxaGetCount(boxa); /* n == size * size */
fpix = fpixCreate(size, size);
for (j = 0; j < n; j++) {
box = boxaGetBox(boxa, j, L_CLONE);
pixMeanInRectangle(pixs, box, pix_mac, &val);
fpixSetPixel(fpix, j % size, j / size, val);
boxDestroy(&box);
}
fpixaAddFPix(*pfpixa, fpix, L_INSERT);
boxaDestroy(&boxa);
}
pixDestroy(&pix_mac);
boxaaDestroy(&baa);
return 0;
}
/*!
* pixQuadtreeVariance()
*
* Input: pixs (8 bpp, no colormap)
* nlevels (in quadtree)
* *pix_ma (input mean accumulator; can be null)
* *dpix_msa (input mean square accumulator; can be null)
* *pfpixa_v (<optional return> variance values in quadtree)
* *pfpixa_rv (<optional return> root variance values in quadtree)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) The returned fpixav and fpixarv have @nlevels of fpix,
* each containing at the respective levels the variance
* and root variance values.
*/
l_int32
pixQuadtreeVariance(PIX *pixs,
l_int32 nlevels,
PIX *pix_ma,
DPIX *dpix_msa,
FPIXA **pfpixa_v,
FPIXA **pfpixa_rv) {
l_int32 i, j, w, h, size, n;
l_float32 var, rvar;
BOX *box;
BOXA *boxa;
BOXAA *baa;
FPIX *fpixv, *fpixrv;
PIX *pix_mac; /* copy of mean accumulator */
DPIX *dpix_msac; /* msa clone */
PROCNAME("pixQuadtreeVariance");
if (!pfpixa_v && !pfpixa_rv)
return ERROR_INT("neither &fpixav nor &fpixarv defined", procName, 1);
if (pfpixa_v) *pfpixa_v = NULL;
if (pfpixa_rv) *pfpixa_rv = NULL;
if (!pixs || pixGetDepth(pixs) != 8)
return ERROR_INT("pixs not defined or not 8 bpp", procName, 1);
pixGetDimensions(pixs, &w, &h, NULL);
if (nlevels > quadtreeMaxLevels(w, h))
return ERROR_INT("nlevels too large for image", procName, 1);
if (!pix_ma)
pix_mac = pixBlockconvAccum(pixs);
else
pix_mac = pixClone(pix_ma);
if (!pix_mac)
return ERROR_INT("pix_mac not made", procName, 1);
if (!dpix_msa)
dpix_msac = pixMeanSquareAccum(pixs);
else
dpix_msac = dpixClone(dpix_msa);
if (!dpix_msac)
return ERROR_INT("dpix_msac not made", procName, 1);
if ((baa = boxaaQuadtreeRegions(w, h, nlevels)) == NULL) {
pixDestroy(&pix_mac);
dpixDestroy(&dpix_msac);
return ERROR_INT("baa not made", procName, 1);
}
if (pfpixa_v) *pfpixa_v = fpixaCreate(nlevels);
if (pfpixa_rv) *pfpixa_rv = fpixaCreate(nlevels);
for (i = 0; i < nlevels; i++) {
boxa = boxaaGetBoxa(baa, i, L_CLONE);
size = 1 << i;
n = boxaGetCount(boxa); /* n == size * size */
if (pfpixa_v) fpixv = fpixCreate(size, size);
if (pfpixa_rv) fpixrv = fpixCreate(size, size);
for (j = 0; j < n; j++) {
box = boxaGetBox(boxa, j, L_CLONE);
pixVarianceInRectangle(pixs, box, pix_mac, dpix_msac, &var, &rvar);
if (pfpixa_v) fpixSetPixel(fpixv, j % size, j / size, var);
if (pfpixa_rv) fpixSetPixel(fpixrv, j % size, j / size, rvar);
boxDestroy(&box);
}
if (pfpixa_v) fpixaAddFPix(*pfpixa_v, fpixv, L_INSERT);
if (pfpixa_rv) fpixaAddFPix(*pfpixa_rv, fpixrv, L_INSERT);
boxaDestroy(&boxa);
}
pixDestroy(&pix_mac);
dpixDestroy(&dpix_msac);
boxaaDestroy(&baa);
return 0;
}
