/*!
* \brief pixAssignToNearestColor()
*
* \param[in] pixd 8 bpp, colormapped
* \param[in] pixs 32 bpp; 24-bit color
* \param[in] pixm [optional] 1 bpp
* \param[in] level of octcube used for finding nearest color in cmap
* \param[in] countarray [optional] ptr to array, in which we can store
* the number of pixels found in each color in
* the colormap in pixd
* \return 0 if OK, 1 on error
*
* <pre>
* Notes:
* (1) This is used in phase 2 of color segmentation, where pixs
* is the original input image to pixColorSegment(), and
* pixd is the colormapped image returned from
* pixColorSegmentCluster(). It is also used, with a mask,
* in phase 4.
* (2) This is an in-place operation.
* (3) The colormap in pixd is unchanged.
* (4) pixs and pixd must be the same size (w, h).
* (5) The selection mask pixm can be null. If it exists, it must
* be the same size as pixs and pixd, and only pixels
* corresponding to fg in pixm are assigned. Set to
* NULL if all pixels in pixd are to be assigned.
* (6) The countarray can be null. If it exists, it is pre-allocated
* and of a size at least equal to the size of the colormap in pixd.
* (7) This does a best-fit (non-greedy) assignment of pixels to
* existing clusters. Specifically, it assigns each pixel
* in pixd to the color index in the pixd colormap that has a
* color closest to the corresponding rgb pixel in pixs.
* (8) 'level' is the octcube level used to quickly find the nearest
* color in the colormap for each pixel. For color segmentation,
* this parameter is set to LEVEL_IN_OCTCUBE.
* (9) We build a mapping table from octcube to colormap index so
* that this function can run in a time (otherwise) independent
* of the number of colors in the colormap. This avoids a
* brute-force search for the closest colormap color to each
* pixel in the image.
* </pre>
*/
l_ok
pixAssignToNearestColor(PIX *pixd,
PIX *pixs,
PIX *pixm,
l_int32 level,
l_int32 *countarray)
{
l_int32 w, h, wpls, wpld, wplm, i, j, success;
l_int32 rval, gval, bval, index;
l_int32 *cmaptab;
l_uint32 octindex;
l_uint32 *rtab, *gtab, *btab;
l_uint32 *ppixel;
l_uint32 *datas, *datad, *datam, *lines, *lined, *linem;
PIXCMAP *cmap;
PROCNAME("pixAssignToNearestColor");
if (!pixd)
return ERROR_INT("pixd not defined", procName, 1);
if ((cmap = pixGetColormap(pixd)) == NULL)
return ERROR_INT("cmap not found", procName, 1);
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
if (pixGetDepth(pixs) != 32)
return ERROR_INT("pixs not 32 bpp", procName, 1);
if (level < 1 || level > 6)
return ERROR_INT("level not in [1 ... 6]", procName, 1);
/* Set up the tables to map rgb to the nearest colormap index */
success = TRUE;
makeRGBToIndexTables(&rtab, >ab, &btab, level);
cmaptab = pixcmapToOctcubeLUT(cmap, level, L_MANHATTAN_DISTANCE);
if (!rtab || !gtab || !btab || !cmaptab) {
L_ERROR("failure to make a table\n", procName);
success = FALSE;
goto cleanup_arrays;
}
pixGetDimensions(pixs, &w, &h, NULL);
datas = pixGetData(pixs);
datad = pixGetData(pixd);
wpls = pixGetWpl(pixs);
wpld = pixGetWpl(pixd);
if (pixm) {
datam = pixGetData(pixm);
wplm = pixGetWpl(pixm);
}
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
if (pixm)
linem = datam + i * wplm;
for (j = 0; j < w; j++) {
if (pixm) {
if (!GET_DATA_BIT(linem, j))
continue;
}
ppixel = lines + j;
rval = GET_DATA_BYTE(ppixel, COLOR_RED);
gval = GET_DATA_BYTE(ppixel, COLOR_GREEN);
bval = GET_DATA_BYTE(ppixel, COLOR_BLUE);
/* Map from rgb to octcube index */
getOctcubeIndexFromRGB(rval, gval, bval, rtab, gtab, btab,
&octindex);
/* Map from octcube index to nearest colormap index */
index = cmaptab[octindex];
if (countarray)
countarray[index]++;
SET_DATA_BYTE(lined, j, index);
}
}
cleanup_arrays:
LEPT_FREE(cmaptab);
LEPT_FREE(rtab);
LEPT_FREE(gtab);
LEPT_FREE(btab);
return (success) ? 0 : 1;
}
/*!
* pixAssignToNearestColor()
*
* Input: pixd (8 bpp, colormapped)
* pixs (32 bpp; 24-bit color)
* pixm (<optional> 1 bpp)
* level (of octcube used for finding nearest color in cmap)
* countarray (<optional> ptr to array, in which we can store
* the number of pixels found in each color in
* the colormap in pixd)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) This is used in phase 2 of color segmentation, where pixs
* is the original input image to pixColorSegment(), and
* pixd is the colormapped image returned from
* pixColorSegmentCluster(). It is also used, with a mask,
* in phase 4.
* (2) This is an in-place operation.
* (3) The colormap in pixd is unchanged.
* (4) pixs and pixd must be the same size (w, h).
* (5) The selection mask pixm can be null. If it exists, it must
* be the same size as pixs and pixd, and only pixels
* corresponding to fg in pixm are assigned. Set to
* NULL if all pixels in pixd are to be assigned.
* (6) The countarray can be null. If it exists, it is pre-allocated
* and of a size at least equal to the size of the colormap in pixd.
* (7) This does a best-fit (non-greedy) assignment of pixels to
* existing clusters. Specifically, it assigns each pixel
* in pixd to the color index in the pixd colormap that has a
* color closest to the corresponding rgb pixel in pixs.
* (8) 'level' is the octcube level used to quickly find the nearest
* color in the colormap for each pixel. For color segmentation,
* this parameter is set to LEVEL_IN_OCTCUBE.
* (9) We build a mapping table from octcube to colormap index so
* that this function can run in a time (otherwise) independent
* of the number of colors in the colormap. This avoids a
* brute-force search for the closest colormap color to each
* pixel in the image.
*/
l_int32
pixAssignToNearestColor(PIX *pixd,
PIX *pixs,
PIX *pixm,
l_int32 level,
l_int32 *countarray)
{
l_int32 w, h, wpls, wpld, wplm, i, j;
l_int32 rval, gval, bval, index;
l_int32 *cmaptab;
l_uint32 octindex;
l_uint32 *rtab, *gtab, *btab;
l_uint32 *ppixel;
l_uint32 *datas, *datad, *datam, *lines, *lined, *linem;
PIXCMAP *cmap;
PROCNAME("pixAssignToNearestColor");
if (!pixd)
return ERROR_INT("pixd not defined", procName, 1);
if ((cmap = pixGetColormap(pixd)) == NULL)
return ERROR_INT("cmap not found", procName, 1);
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
if (pixGetDepth(pixs) != 32)
return ERROR_INT("pixs not 32 bpp", procName, 1);
/* Set up the tables to map rgb to the nearest colormap index */
if (makeRGBToIndexTables(&rtab, >ab, &btab, level))
return ERROR_INT("index tables not made", procName, 1);
if ((cmaptab = pixcmapToOctcubeLUT(cmap, level, L_MANHATTAN_DISTANCE))
== NULL)
return ERROR_INT("cmaptab not made", procName, 1);
w = pixGetWidth(pixs);
h = pixGetHeight(pixs);
datas = pixGetData(pixs);
datad = pixGetData(pixd);
wpls = pixGetWpl(pixs);
wpld = pixGetWpl(pixd);
if (pixm) {
datam = pixGetData(pixm);
wplm = pixGetWpl(pixm);
}
for (i = 0; i < h; i++) {
lines = datas + i * wpls;
lined = datad + i * wpld;
if (pixm)
linem = datam + i * wplm;
for (j = 0; j < w; j++) {
if (pixm) {
if (!GET_DATA_BIT(linem, j))
continue;
}
ppixel = lines + j;
rval = GET_DATA_BYTE(ppixel, COLOR_RED);
gval = GET_DATA_BYTE(ppixel, COLOR_GREEN);
bval = GET_DATA_BYTE(ppixel, COLOR_BLUE);
/* Map from rgb to octcube index */
getOctcubeIndexFromRGB(rval, gval, bval, rtab, gtab, btab,
&octindex);
/* Map from octcube index to nearest colormap index */
index = cmaptab[octindex];
if (countarray)
countarray[index]++;
SET_DATA_BYTE(lined, j, index);
}
}
FREE(cmaptab);
FREE(rtab);
FREE(gtab);
FREE(btab);
return 0;
}