/*!
* dpixMeanSquareAccum()
*
* Input: pixs (1 bpp or 8 bpp grayscale)
* Return: dpix (64 bit array), or null on error
*
* Notes:
* (1) This is an extension to the standard pixMeanSquareAccum()
* implementation provided by Leptonica, to handle 1bpp binary pix
* transparently.
* (1) Similar to pixBlockconvAccum(), this computes the
* sum of the squares of the pixel values in such a way
* that the value at (i,j) is the sum of all squares in
* the rectangle from the origin to (i,j).
* (2) The general recursion relation (v are squared pixel values) is
* a(i,j) = v(i,j) + a(i-1, j) + a(i, j-1) - a(i-1, j-1)
* For the first line, this reduces to the special case
* a(i,j) = v(i,j) + a(i, j-1)
* For the first column, the special case is
* a(i,j) = v(i,j) + a(i-1, j)
*/
DPIX *
dpixMeanSquareAccum(PIX *pixs)
{
l_int32 i, j, w, h, d, wpl, wpls, val;
l_uint32 *datas, *lines;
l_float64 *data, *line, *linep;
DPIX *dpix;
PROCNAME("dpixMeanSquareAccum");
if (!pixs)
return (DPIX *)ERROR_PTR("pixs not defined", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 1 && d != 8)
return (DPIX *)ERROR_PTR("pixs not 1 bpp or 8 bpp", procName, NULL);
if ((dpix = dpixCreate(w, h)) == NULL)
return (DPIX *)ERROR_PTR("dpix not made", procName, NULL);
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
data = dpixGetData(dpix);
wpl = dpixGetWpl(dpix);
lines = datas;
line = data;
for (j = 0; j < w; j++) { /* first line */
val = d == 1 ? GET_DATA_BIT(lines, j) : GET_DATA_BYTE(lines, j);
if (j == 0)
line[0] = val * val;
else
line[j] = line[j - 1] + val * val;
}
/* Do the other lines */
for (i = 1; i < h; i++) {
lines = datas + i * wpls;
line = data + i * wpl; /* current dest line */
linep = line - wpl;; /* prev dest line */
for (j = 0; j < w; j++) {
val = d == 1 ? GET_DATA_BIT(lines, j) : GET_DATA_BYTE(lines, j);
if (j == 0)
line[0] = linep[0] + val * val;
else
line[j] = line[j - 1] + linep[j] - linep[j - 1] + val * val;
}
}
return dpix;
}
/*!
* dpixCreateTemplate()
*
* Input: dpixs
* Return: dpixd, or null on error
*
* Notes:
* (1) Makes a DPix of the same size as the input DPix, with the
* data array allocated and initialized to 0.
* (2) Copies the resolution.
*/
DPIX *
dpixCreateTemplate(DPIX *dpixs)
{
l_int32 w, h;
DPIX *dpixd;
PROCNAME("dpixCreateTemplate");
if (!dpixs)
return (DPIX *)ERROR_PTR("dpixs not defined", procName, NULL);
dpixGetDimensions(dpixs, &w, &h);
dpixd = dpixCreate(w, h);
dpixCopyResolution(dpixd, dpixs);
return dpixd;
}
/*!
* dpixInverseDFT()
*
* Input: dft
* w, h (image size)
* Return: dpix (unnormalized), or null on error
*/
DPIX *
dpixInverseDFT(fftw_complex *dft,
l_int32 w,
l_int32 h)
{
DPIX *dpix;
fftw_plan plan;
PROCNAME("dpixInverseDFT");
if (!dft)
return (DPIX *)ERROR_PTR("dft not defined", procName, NULL);
if ((dpix = dpixCreate(w, h)) == NULL)
return (DPIX *)ERROR_PTR("dpix not made", procName, NULL);
/* Compute the inverse DFT, storing the results into DPix */
plan = fftw_plan_dft_c2r_2d(h, w, dft, (double *) dpixGetData(dpix), FFTW_ESTIMATE);
fftw_execute(plan);
fftw_destroy_plan(plan);
dpixNormalize(dpix, dpix);
return dpix;
}
/*!
* pixConvertToDPix()
*
* Input: pix (1, 2, 4, 8, 16 or 32 bpp)
* ncomps (number of components: 3 for RGB, 1 otherwise)
* shiftflag (L_NO_SHIFTING or L_WITH_SHIFTING)
* Return: dpix, or null on error
*
* Notes:
* (1) If colormapped, remove to grayscale.
* (2) If 32 bpp and @ncomps == 3, this is RGB; convert to luminance.
* In all other cases the src image is treated as having a single
* component of pixel values.
* (3) Set @shiftflag to L_WITH_SHIFTING to move the DC of the
* the DFT to the center of pix.
*/
DPIX *
pixConvertToDPix(PIX *pixs,
l_int32 ncomps,
l_int32 shiftflag)
{
l_int32 w, h, d;
l_int32 i, j, val, wplt, wpld;
l_uint32 uval;
l_uint32 *datat, *linet;
l_float64 *datad, *lined;
PIX *pixt;
DPIX *dpixd;
PROCNAME("pixConvertToDPix");
if (!pixs)
return (DPIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (shiftflag != L_NO_SHIFTING && shiftflag != L_WITH_SHIFTING)
return (DPIX *)ERROR_PTR("invalid shiftflag", procName, NULL);
if (pixGetColormap(pixs))
pixt = pixRemoveColormap(pixs, REMOVE_CMAP_TO_GRAYSCALE);
else if (pixGetDepth(pixs) == 32 && ncomps == 3)
pixt = pixConvertRGBToLuminance(pixs);
else
pixt = pixClone(pixs);
pixGetDimensions(pixt, &w, &h, &d);
if ((dpixd = dpixCreate(w, h)) == NULL)
return (DPIX *)ERROR_PTR("dpixd not made", procName, NULL);
datat = pixGetData(pixt);
wplt = pixGetWpl(pixt);
datad = dpixGetData(dpixd);
wpld = dpixGetWpl(dpixd);
for (i = 0; i < h; i++) {
linet = datat + i * wplt;
lined = datad + i * wpld;
if (d == 1) {
for (j = 0; j < w; j++) {
val = GET_DATA_BIT(linet, j);
lined[j] = shiftflag ? (l_float64)(val * pow(-1, i + j)) : (l_float64)val;
}
}
else if (d == 2) {
for (j = 0; j < w; j++) {
val = GET_DATA_DIBIT(linet, j);
lined[j] = shiftflag ? (l_float64)(val * pow(-1, i + j)) : (l_float64)val;
}
}
else if (d == 4) {
for (j = 0; j < w; j++) {
val = GET_DATA_QBIT(linet, j);
lined[j] = shiftflag ? (l_float64)(val * pow(-1, i + j)) : (l_float64)val;
}
}
else if (d == 8) {
for (j = 0; j < w; j++) {
val = GET_DATA_BYTE(linet, j);
lined[j] = shiftflag ? (l_float64)(val * pow(-1, i + j)) : (l_float64)val;
}
}
else if (d == 16) {
for (j = 0; j < w; j++) {
val = GET_DATA_TWO_BYTES(linet, j);
lined[j] = shiftflag ? (l_float64)(val * pow(-1, i + j)) : (l_float64)val;
}
}
else if (d == 32) {
for (j = 0; j < w; j++) {
uval = GET_DATA_FOUR_BYTES(linet, j);
lined[j] = shiftflag ? (l_float64)(uval * pow(-1, i + j)) : (l_float64)uval;
}
}
}
pixDestroy(&pixt);
return dpixd;
}
