/*!
* \brief pixConnCompTransform()
*
* \param[in] pixs 1 bpp
* \param[in] connect connectivity: 4 or 8
* \param[in] depth of pixd: 8 or 16 bpp; use 0 for auto determination
* \return pixd 8, 16 or 32 bpp, or NULL on error
*
* <pre>
* Notes:
* (1) pixd is 8, 16 or 32 bpp, and the pixel values label the
* fg component, starting with 1. Pixels in the bg are labelled 0.
* (2) If %depth = 0, the depth of pixd is 8 if the number of c.c.
* is less than 254, 16 if the number of c.c is less than 0xfffe,
* and 32 otherwise.
* (3) If %depth = 8, the assigned label for the n-th component is
* 1 + n % 254. We use mod 254 because 0 is uniquely assigned
* to black: e.g., see pixcmapCreateRandom(). Likewise,
* if %depth = 16, the assigned label uses mod(2^16 - 2), and
* if %depth = 32, no mod is taken.
* </pre>
*/
PIX *
pixConnCompTransform(PIX *pixs,
l_int32 connect,
l_int32 depth)
{
l_int32 i, n, index, w, h, xb, yb, wb, hb;
BOXA *boxa;
PIX *pix1, *pix2, *pixd;
PIXA *pixa;
PROCNAME("pixConnCompTransform");
if (!pixs || pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs undefined or not 1 bpp", procName, NULL);
if (connect != 4 && connect != 8)
return (PIX *)ERROR_PTR("connectivity must be 4 or 8", procName, NULL);
if (depth != 0 && depth != 8 && depth != 16 && depth != 32)
return (PIX *)ERROR_PTR("depth must be 0, 8, 16 or 32", procName, NULL);
boxa = pixConnComp(pixs, &pixa, connect);
n = pixaGetCount(pixa);
boxaDestroy(&boxa);
pixGetDimensions(pixs, &w, &h, NULL);
if (depth == 0) {
if (n < 254)
depth = 8;
else if (n < 0xfffe)
depth = 16;
else
depth = 32;
}
pixd = pixCreate(w, h, depth);
pixSetSpp(pixd, 1);
if (n == 0) { /* no fg */
pixaDestroy(&pixa);
return pixd;
}
/* Label each component and blit it in */
for (i = 0; i < n; i++) {
pixaGetBoxGeometry(pixa, i, &xb, &yb, &wb, &hb);
pix1 = pixaGetPix(pixa, i, L_CLONE);
if (depth == 8) {
index = 1 + (i % 254);
pix2 = pixConvert1To8(NULL, pix1, 0, index);
} else if (depth == 16) {
index = 1 + (i % 0xfffe);
pix2 = pixConvert1To16(NULL, pix1, 0, index);
} else { /* depth == 32 */
index = 1 + i;
pix2 = pixConvert1To32(NULL, pix1, 0, index);
}
pixRasterop(pixd, xb, yb, wb, hb, PIX_PAINT, pix2, 0, 0);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pixaDestroy(&pixa);
return pixd;
}
/*!
* pixConnCompAreaTransform()
*
* Input: pixs (1 bpp)
* connect (connectivity: 4 or 8)
* Return: pixd (16 bpp), or null on error
*
* Notes:
* (1) The pixel values in pixd label the area of the fg component
* to which the pixel belongs. Pixels in the bg are labelled 0.
* (2) The pixel values cannot exceed 2^16 - 1, even if the area
* of the c.c. is larger.
* (3) For purposes of visualization, the output can be converted
* to 8 bpp, using pixConvert16To8() or pixMaxDynamicRange().
*/
PIX *
pixConnCompAreaTransform(PIX *pixs,
l_int32 connect)
{
l_int32 i, n, npix, w, h, xb, yb, wb, hb;
l_int32 *tab8;
BOXA *boxa;
PIX *pix1, *pix2, *pixd;
PIXA *pixa;
PROCNAME("pixConnCompTransform");
if (!pixs || pixGetDepth(pixs) != 1)
return (PIX *)ERROR_PTR("pixs undefined or not 1 bpp", procName, NULL);
if (connect != 4 && connect != 8)
return (PIX *)ERROR_PTR("connectivity must be 4 or 8", procName, NULL);
boxa = pixConnComp(pixs, &pixa, connect);
n = pixaGetCount(pixa);
boxaDestroy(&boxa);
pixGetDimensions(pixs, &w, &h, NULL);
pixd = pixCreate(w, h, 16);
if (n == 0) { /* no fg */
pixaDestroy(&pixa);
return pixd;
}
/* Label each component and blit it in */
tab8 = makePixelSumTab8();
for (i = 0; i < n; i++) {
pixaGetBoxGeometry(pixa, i, &xb, &yb, &wb, &hb);
pix1 = pixaGetPix(pixa, i, L_CLONE);
pixCountPixels(pix1, &npix, tab8);
npix = L_MIN(npix, 0xffff);
pix2 = pixConvert1To16(NULL, pix1, 0, npix);
pixRasterop(pixd, xb, yb, wb, hb, PIX_PAINT, pix2, 0, 0);
pixDestroy(&pix1);
pixDestroy(&pix2);
}
pixaDestroy(&pixa);
FREE(tab8);
return pixd;
}
