// Distorts anything that has a non-null pointer with the same pseudo-random
// perspective distortion. Width and height only need to be set if there
// is no pix. If there is a pix, then they will be taken from there.
void GeneratePerspectiveDistortion(int width, int height, TRand* randomizer,
Pix** pix, GenericVector<TBOX>* boxes) {
if (pix != nullptr && *pix != nullptr) {
width = pixGetWidth(*pix);
height = pixGetHeight(*pix);
}
float* im_coeffs = nullptr;
float* box_coeffs = nullptr;
l_int32 incolor =
ProjectiveCoeffs(width, height, randomizer, &im_coeffs, &box_coeffs);
if (pix != nullptr && *pix != nullptr) {
// Transform the image.
Pix* transformed = pixProjective(*pix, im_coeffs, incolor);
if (transformed == nullptr) {
tprintf("Projective transformation failed!!\n");
return;
}
pixDestroy(pix);
*pix = transformed;
}
if (boxes != nullptr) {
// Transform the boxes.
for (int b = 0; b < boxes->size(); ++b) {
int x1, y1, x2, y2;
const TBOX& box = (*boxes)[b];
projectiveXformSampledPt(box_coeffs, box.left(), height - box.top(), &x1,
&y1);
projectiveXformSampledPt(box_coeffs, box.right(), height - box.bottom(),
&x2, &y2);
TBOX new_box1(x1, height - y2, x2, height - y1);
projectiveXformSampledPt(box_coeffs, box.left(), height - box.bottom(),
&x1, &y1);
projectiveXformSampledPt(box_coeffs, box.right(), height - box.top(), &x2,
&y2);
TBOX new_box2(x1, height - y1, x2, height - y2);
(*boxes)[b] = new_box1.bounding_union(new_box2);
}
}
free(im_coeffs);
free(box_coeffs);
}
/*!
* pixProjectiveSampled()
*
* Input: pixs (all depths)
* vc (vector of 8 coefficients for projective transformation)
* incolor (L_BRING_IN_WHITE, L_BRING_IN_BLACK)
* Return: pixd, or null on error
*
* Notes:
* (1) Brings in either black or white pixels from the boundary.
* (2) Retains colormap, which you can do for a sampled transform..
* (3) For 8 or 32 bpp, much better quality is obtained by the
* somewhat slower pixProjective(). See that function
* for relative timings between sampled and interpolated.
*/
PIX *
pixProjectiveSampled(PIX *pixs,
l_float32 *vc,
l_int32 incolor)
{
l_int32 i, j, w, h, d, x, y, wpls, wpld, color, cmapindex;
l_uint32 val;
l_uint32 *datas, *datad, *lines, *lined;
PIX *pixd;
PIXCMAP *cmap;
PROCNAME("pixProjectiveSampled");
if (!pixs)
return (PIX *)ERROR_PTR("pixs not defined", procName, NULL);
if (!vc)
return (PIX *)ERROR_PTR("vc not defined", procName, NULL);
if (incolor != L_BRING_IN_WHITE && incolor != L_BRING_IN_BLACK)
return (PIX *)ERROR_PTR("invalid incolor", procName, NULL);
pixGetDimensions(pixs, &w, &h, &d);
if (d != 1 && d != 2 && d != 4 && d != 8 && d != 32)
return (PIX *)ERROR_PTR("depth not 1, 2, 4, 8 or 16", procName, NULL);
/* Init all dest pixels to color to be brought in from outside */
pixd = pixCreateTemplate(pixs);
if ((cmap = pixGetColormap(pixs)) != NULL) {
if (incolor == L_BRING_IN_WHITE)
color = 1;
else
color = 0;
pixcmapAddBlackOrWhite(cmap, color, &cmapindex);
pixSetAllArbitrary(pixd, cmapindex);
}
else {
if ((d == 1 && incolor == L_BRING_IN_WHITE) ||
(d > 1 && incolor == L_BRING_IN_BLACK))
pixClearAll(pixd);
else
pixSetAll(pixd);
}
/* Scan over the dest pixels */
datas = pixGetData(pixs);
wpls = pixGetWpl(pixs);
datad = pixGetData(pixd);
wpld = pixGetWpl(pixd);
for (i = 0; i < h; i++) {
lined = datad + i * wpld;
for (j = 0; j < w; j++) {
projectiveXformSampledPt(vc, j, i, &x, &y);
if (x < 0 || y < 0 || x >=w || y >= h)
continue;
lines = datas + y * wpls;
if (d == 1) {
val = GET_DATA_BIT(lines, x);
SET_DATA_BIT_VAL(lined, j, val);
}
else if (d == 8) {
val = GET_DATA_BYTE(lines, x);
SET_DATA_BYTE(lined, j, val);
}
else if (d == 32) {
lined[j] = lines[x];
}
else if (d == 2) {
val = GET_DATA_DIBIT(lines, x);
SET_DATA_DIBIT(lined, j, val);
}
else if (d == 4) {
val = GET_DATA_QBIT(lines, x);
SET_DATA_QBIT(lined, j, val);
}
}
}
return pixd;
}
