/*!
* pixCopyColormap()
*
* Input: src and dest Pix
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) This always destroys any colormap in pixd (except if
* the operation is a no-op.
*/
l_int32
pixCopyColormap(PIX *pixd,
PIX *pixs)
{
PIXCMAP *cmaps, *cmapd;
PROCNAME("pixCopyColormap");
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
if (!pixd)
return ERROR_INT("pixd not defined", procName, 1);
if (pixs == pixd)
return 0; /* no-op */
pixDestroyColormap(pixd);
if ((cmaps = pixGetColormap(pixs)) == NULL) /* not an error */
return 0;
if ((cmapd = pixcmapCopy(cmaps)) == NULL)
return ERROR_INT("cmapd not made", procName, 1);
pixSetColormap(pixd, cmapd);
return 0;
}
/*!
* pixcmapColorToGray()
*
* Input: cmap
* rwt, gwt, bwt (non-negative; these should add to 1.0)
* Return: cmap (gray), or null on error
*
* Notes:
* (1) This creates a gray colormap from an arbitrary colormap.
* (2) In use, attach the output gray colormap to the pix
* (or a copy of it) that provided the input colormap.
*/
PIXCMAP *
pixcmapColorToGray(PIXCMAP *cmaps,
l_float32 rwt,
l_float32 gwt,
l_float32 bwt)
{
l_int32 i, n, rval, gval, bval, val;
l_float32 sum;
PIXCMAP *cmapd;
PROCNAME("pixcmapColorToGray");
if (!cmaps)
return (PIXCMAP *)ERROR_PTR("cmaps not defined", procName, NULL);
if (rwt < 0.0 || gwt < 0.0 || bwt < 0.0)
return (PIXCMAP *)ERROR_PTR("weights not all >= 0.0", procName, NULL);
/* Make sure the sum of weights is 1.0; otherwise, you can get
* overflow in the gray value. */
sum = rwt + gwt + bwt;
if (sum == 0.0) {
L_WARNING("all weights zero; setting equal to 1/3", procName);
rwt = gwt = bwt = 0.33333;
sum = 1.0;
}
if (L_ABS(sum - 1.0) > 0.0001) { /* maintain ratios with sum == 1.0 */
L_WARNING("weights don't sum to 1; maintaining ratios", procName);
rwt = rwt / sum;
gwt = gwt / sum;
bwt = bwt / sum;
}
cmapd = pixcmapCopy(cmaps);
n = pixcmapGetCount(cmapd);
for (i = 0; i < n; i++) {
pixcmapGetColor(cmapd, i, &rval, &gval, &bval);
val = (l_int32)(rwt * rval + gwt * gval + bwt * bval + 0.5);
pixcmapResetColor(cmapd, i, val, val, val);
}
return cmapd;
}
/*!
* pixColorGrayCmap()
*
* Input: pixs (2, 4 or 8 bpp, with colormap)
* box (<optional> region to set color; can be NULL)
* type (L_PAINT_LIGHT, L_PAINT_DARK)
* rval, gval, bval (target color)
* Return: 0 if OK, 1 on error
*
* Notes:
* (1) This is an in-place operation.
* (2) If type == L_PAINT_LIGHT, it colorizes non-black pixels,
* preserving antialiasing.
* If type == L_PAINT_DARK, it colorizes non-white pixels,
* preserving antialiasing.
* (3) If box is NULL, applies function to the entire image; otherwise,
* clips the operation to the intersection of the box and pix.
* (4) This can also be called through pixColorGray().
* (5) This increases the colormap size by the number of
* different gray (non-black or non-white) colors in the
* input colormap. If there is not enough room in the colormap
* for this expansion, it returns 1 (error), and the caller
* should check the return value. If an error is returned
* and the cmap is only 2 or 4 bpp, the pix can be converted
* to 8 bpp and this function will succeed if run again on
* a larger colormap.
* (6) Using the darkness of each original pixel in the rect,
* it generates a new color (based on the input rgb values).
* If type == L_PAINT_LIGHT, the new color is a (generally)
* darken-to-black version of the input rgb color, where the
* amount of darkening increases with the darkness of the
* original pixel color.
* If type == L_PAINT_DARK, the new color is a (generally)
* faded-to-white version of the input rgb color, where the
* amount of fading increases with the brightness of the
* original pixel color.
*/
l_int32
pixColorGrayCmap(PIX *pixs,
BOX *box,
l_int32 type,
l_int32 rval,
l_int32 gval,
l_int32 bval)
{
l_int32 i, j, w, h, d, x1, y1, x2, y2, bw, bh, wpl;
l_int32 val, nval;
l_int32 *map;
l_uint32 *line, *data;
NUMA *na;
PIX *pixt;
PIXCMAP *cmap, *cmapc;
PROCNAME("pixColorGrayCmap");
if (!pixs)
return ERROR_INT("pixs not defined", procName, 1);
if ((cmap = pixGetColormap(pixs)) == NULL)
return ERROR_INT("no colormap", procName, 1);
d = pixGetDepth(pixs);
if (d != 2 && d != 4 && d != 8)
return ERROR_INT("depth not in {2, 4, 8}", procName, 1);
if (type != L_PAINT_DARK && type != L_PAINT_LIGHT)
return ERROR_INT("invalid type", procName, 1);
/* If 2 bpp or 4 bpp, see if the new colors will fit into
* the existing colormap. If not, convert in-place to 8 bpp. */
if (d == 2 || d == 4) {
cmapc = pixcmapCopy(cmap); /* experiment with a copy */
if (addColorizedGrayToCmap(cmapc, type, rval, gval, bval, NULL)) {
pixt = pixConvertTo8(pixs, 1);
pixTransferAllData(pixs, &pixt, 0, 0);
}
pixcmapDestroy(&cmapc);
}
/* Find gray colors, add the corresponding new colors,
* and set up a mapping table from gray to new.
* That table has the value 256 for all colors that are
* not to be mapped. */
cmap = pixGetColormap(pixs);
if (addColorizedGrayToCmap(cmap, type, rval, gval, bval, &na)) {
numaDestroy(&na);
return ERROR_INT("no room; cmap full", procName, 1);
}
map = numaGetIArray(na);
/* Determine the region of substitution */
pixGetDimensions(pixs, &w, &h, &d); /* d may be different */
data = pixGetData(pixs);
wpl = pixGetWpl(pixs);
if (!box) {
x1 = y1 = 0;
x2 = w;
y2 = h;
}
else {
boxGetGeometry(box, &x1, &y1, &bw, &bh);
x2 = x1 + bw - 1;
y2 = y1 + bh - 1;
}
/* Remap gray pixels in the region */
for (i = y1; i <= y2; i++) {
if (i < 0 || i >= h) /* clip */
continue;
line = data + i * wpl;
for (j = x1; j <= x2; j++) {
if (j < 0 || j >= w) /* clip */
continue;
switch (d)
{
case 2:
val = GET_DATA_DIBIT(line, j);
nval = map[val];
if (nval != 256)
SET_DATA_DIBIT(line, j, nval);
break;
case 4:
val = GET_DATA_QBIT(line, j);
nval = map[val];
if (nval != 256)
SET_DATA_QBIT(line, j, nval);
break;
case 8:
val = GET_DATA_BYTE(line, j);
nval = map[val];
if (nval != 256)
SET_DATA_BYTE(line, j, nval);
break;
}
}
}
FREE(map);
numaDestroy(&na);
return 0;
}
