int main(int argc, char** argv)
{
if (argc < 2)
{
std::cerr << "Use " << argv[0] << " filename" << std::endl;
return 1;
}
// load image
int width, height, nc;
float* rgba = stbi_loadf(argv[1], &width, &height, &nc, 4);
if (stbi_failure_reason())
{
std::cerr << "stbi: " << stbi_failure_reason() << std::endl;
return 1;
}
// create summed area table of luminance image
summed_area_table lum_sat;
lum_sat.create_lum(rgba, width, height, 4);
// apply median cut
std::vector<sat_region> regions;
median_cut(lum_sat, 9, regions); // max 2^n cuts
// create 2d positions from regions
std::vector<float2> lights;
create_lights(regions, lights);
// draw a marker into image for each position
size_t i = 0;
for (auto l = lights.begin(); l != lights.end(); ++l)
{
std::cout << "Light " << i++ << ": (" << l->x << ", " << l->y << ")" << std::endl;
draw(rgba, width, height, *l);
}
// save image with marked samples
std::vector<unsigned char> conv;
conv.resize(width*height*4);
for (size_t i = 0; i < width * height * 4; ++i)
conv[i] = static_cast<unsigned char>(rgba[i]*255);
stbi_write_bmp("test.bmp", width, height, 4, &conv[0]);
return 0;
}
int
quantize(Pixel *pixelData,
uint32_t nPixels,
uint32_t nQuantPixels,
Pixel **palette,
uint32_t *paletteLength,
uint32_t **quantizedPixels,
int kmeans)
{
PixelList *hl[3];
HashTable *h;
BoxNode *root;
uint32_t i;
uint32_t *qp;
uint32_t nPaletteEntries;
uint32_t *avgDist;
uint32_t **avgDistSortKey;
Pixel *p;
#ifndef NO_OUTPUT
uint32_t timer,timer2;
#endif
#ifndef NO_OUTPUT
timer2=clock();
printf ("create hash table..."); fflush(stdout); timer=clock();
#endif
h=create_pixel_hash(pixelData,nPixels);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
if (!h) {
goto error_0;
}
#ifndef NO_OUTPUT
printf ("create lists from hash table..."); fflush(stdout); timer=clock();
#endif
hl[0]=hl[1]=hl[2]=NULL;
hashtable_foreach(h,hash_to_list,hl);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
if (!hl[0]) {
goto error_1;
}
#ifndef NO_OUTPUT
printf ("mergesort lists..."); fflush(stdout); timer=clock();
#endif
for(i=0;i<3;i++) {
hl[i]=mergesort_pixels(hl[i],i);
}
#ifdef TEST_MERGESORT
if (!test_sorted(hl)) {
printf ("bug in mergesort\n");
goto error_1;
}
#endif
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
#ifndef NO_OUTPUT
printf ("median cut..."); fflush(stdout); timer=clock();
#endif
root=median_cut(hl,nPixels,nQuantPixels);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
if (!root) {
goto error_1;
}
nPaletteEntries=0;
#ifndef NO_OUTPUT
printf ("median cut tree to hash table..."); fflush(stdout); timer=clock();
#endif
annotate_hash_table(root,h,&nPaletteEntries);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
#ifndef NO_OUTPUT
printf ("compute palette...\n"); fflush(stdout); timer=clock();
#endif
if (!compute_palette_from_median_cut(pixelData,nPixels,h,&p,nPaletteEntries)) {
goto error_3;
}
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
free_box_tree(root);
root=NULL;
/* malloc check ok, using calloc for overflow */
qp=calloc(nPixels, sizeof(uint32_t));
if (!qp) { goto error_4; }
if (nPaletteEntries > UINT32_MAX / nPaletteEntries ) {
goto error_5;
}
/* malloc check ok, using calloc for overflow, check of n*n above */
avgDist=calloc(nPaletteEntries*nPaletteEntries, sizeof(uint32_t));
if (!avgDist) { goto error_5; }
/* malloc check ok, using calloc for overflow, check of n*n above */
avgDistSortKey=calloc(nPaletteEntries*nPaletteEntries, sizeof(uint32_t *));
if (!avgDistSortKey) { goto error_6; }
if (!build_distance_tables(avgDist,avgDistSortKey,p,nPaletteEntries)) {
goto error_7;
}
if (!map_image_pixels_from_median_box(pixelData,nPixels,p,nPaletteEntries,h,avgDist,avgDistSortKey,qp)) {
goto error_7;
}
#ifdef TEST_NEAREST_NEIGHBOUR
#include <math.h>
{
uint32_t bestmatch,bestdist,dist;
HashTable *h2;
printf ("nearest neighbour search (full search)..."); fflush(stdout); timer=clock();
h2=hashtable_new(unshifted_pixel_hash,unshifted_pixel_cmp);
for (i=0;i<nPixels;i++) {
if (hashtable_lookup(h2,pixelData[i],&paletteEntry)) {
bestmatch=paletteEntry;
} else {
bestmatch=0;
bestdist=
_SQR(pixelData[i].c.r-p[0].c.r)+
_SQR(pixelData[i].c.g-p[0].c.g)+
_SQR(pixelData[i].c.b-p[0].c.b);
for (j=1;j<nPaletteEntries;j++) {
dist=
_SQR(pixelData[i].c.r-p[j].c.r)+
_SQR(pixelData[i].c.g-p[j].c.g)+
_SQR(pixelData[i].c.b-p[j].c.b);
if (dist==bestdist && j==qp[i]) {
bestmatch=j;
}
if (dist<bestdist) {
bestdist=dist;
bestmatch=j;
}
}
hashtable_insert(h2,pixelData[i],bestmatch);
}
if (qp[i]!=bestmatch ) {
printf ("discrepancy in matching algorithms pixel %d [%d %d] %f %f\n",
i,qp[i],bestmatch,
sqrt((double)(_SQR(pixelData[i].c.r-p[qp[i]].c.r)+
_SQR(pixelData[i].c.g-p[qp[i]].c.g)+
_SQR(pixelData[i].c.b-p[qp[i]].c.b))),
sqrt((double)(_SQR(pixelData[i].c.r-p[bestmatch].c.r)+
_SQR(pixelData[i].c.g-p[bestmatch].c.g)+
_SQR(pixelData[i].c.b-p[bestmatch].c.b)))
);
}
}
hashtable_free(h2);
}
#endif
#ifndef NO_OUTPUT
printf ("k means...\n"); fflush(stdout); timer=clock();
#endif
if (kmeans) k_means(pixelData,nPixels,p,nPaletteEntries,qp,kmeans-1);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
#endif
*quantizedPixels=qp;
*palette=p;
*paletteLength=nPaletteEntries;
#ifndef NO_OUTPUT
printf ("cleanup..."); fflush(stdout); timer=clock();
#endif
if (avgDist) free(avgDist);
if (avgDistSortKey) free(avgDistSortKey);
destroy_pixel_hash(h);
#ifndef NO_OUTPUT
printf ("done (%f)\n",(clock()-timer)/(double)CLOCKS_PER_SEC);
printf ("-----\ntotal time %f\n",(clock()-timer2)/(double)CLOCKS_PER_SEC);
#endif
return 1;
error_7:
if (avgDistSortKey) free(avgDistSortKey);
error_6:
if (avgDist) free(avgDist);
error_5:
if (qp) free(qp);
error_4:
if (p) free(p);
error_3:
if (root) free_box_tree(root);
error_1:
destroy_pixel_hash(h);
error_0:
*quantizedPixels=NULL;
*paletteLength=0;
*palette=NULL;
return 0;
}
