/* -------------------------------------------------------------------------
Minimal (unoptimized) example of PatchMatch. Requires that ImageMagick be installed.
To improve generality you can:
- Use whichever distance function you want in dist(), e.g. compare SIFT descriptors computed densely.
- Search over a larger search space, such as rotating+scaling patches (see MATLAB mex for examples of both)
To improve speed you can:
- Turn on optimizations (/Ox /Oi /Oy /fp:fast or -O6 -s -ffast-math -fomit-frame-pointer -fstrength-reduce -msse2 -funroll-loops)
- Use the MATLAB mex which is already tuned for speed
- Use multiple cores, tiling the input. See our publication "The Generalized PatchMatch Correspondence Algorithm"
- Tune the distance computation: manually unroll loops for each patch size, use SSE instructions (see readme)
- Precompute random search samples (to avoid using rand, and mod)
- Move to the GPU
-------------------------------------------------------------------------- */
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef MAX
#define MAX(a, b) ((a)>(b)?(a):(b))
#define MIN(a, b) ((a)<(b)?(a):(b))
#endif
/* -------------------------------------------------------------------------
BITMAP: Minimal image class
------------------------------------------------------------------------- */
class BITMAP { public:
int w, h;
int *data;
BITMAP(int w_, int h_) :w(w_), h(h_) { data = new int[w*h]; }
~BITMAP() { delete[] data; }
int *operator[](int y) { return &data[y*w]; }
};
void check_im() {
if (system("identify > null.txt") != 0) {
fprintf(stderr, "ImageMagick must be installed, and 'convert' and 'identify' must be in the path\n"); exit(1);
}
}
BITMAP *load_bitmap(const char *filename) {
//check_im();
char rawname[256], txtname[256];
strcpy_s(rawname, filename);
strcpy_s(txtname, filename);
if (!strstr(rawname, ".")) { fprintf(stderr, "Error reading image '%s': no extension found\n", filename); exit(1); }
sprintf(strstr(rawname, "."), ".raw");
sprintf(strstr(txtname, "."), ".txt");
char buf[256];
sprintf(buf, "convert %s rgba:%s", filename, rawname);
if (system(buf) != 0) { fprintf(stderr, "Error reading image '%s': ImageMagick convert gave an error\n", filename); exit(1); }
sprintf(buf, "identify -format \"%%w %%h\" %s > %s", filename, txtname);
if (system(buf) != 0) { fprintf(stderr, "Error reading image '%s': ImageMagick identify gave an error\n", filename); exit(1); }
FILE *f = fopen(txtname, "rt");
if (!f) { fprintf(stderr, "Error reading image '%s': could not read output of ImageMagick identify\n", filename); exit(1); }
int w = 0, h = 0;
if (fscanf(f, "%d %d", &w, &h) != 2) { fprintf(stderr, "Error reading image '%s': could not get size from ImageMagick identify\n", filename); exit(1); }
fclose(f);
f = fopen(rawname, "rb");
BITMAP *ans = new BITMAP(w, h);
unsigned char *p = (unsigned char *) ans->data;
for (int i = 0; i < w*h*4; i++) {
int ch = fgetc(f);
if (ch == EOF) { fprintf(stderr, "Error reading image '%s': raw file is smaller than expected size %dx%dx4\n", filename, w, h, 4); exit(1); }
*p++ = ch;
}
fclose(f);
return ans;
}
void save_bitmap(BITMAP *bmp, const char *filename) {
//check_im();
char rawname[256];
strcpy(rawname, filename);
if (!strstr(rawname, ".")) { fprintf(stderr, "Error writing image '%s': no extension found\n", filename); exit(1); }
sprintf(strstr(rawname, "."), ".raw");//strstr查找子字符串
char buf[256];
FILE *f = fopen(rawname, "wb");
if (!f) { fprintf(stderr, "Error writing image '%s': could not open raw temporary file\n", filename); exit(1); }
unsigned char *p = (unsigned char *) bmp->data;
for (int i = 0; i < bmp->w*bmp->h*4; i++) {
fputc(*p++, f);
}
fclose(f);
sprintf(buf, "convert -size %dx%d -depth 8 rgba:%s %s", bmp->w, bmp->h, rawname, filename);
if (system(buf) != 0) { fprintf(stderr, "Error writing image '%s': ImageMagick convert gave an error\n", filename); exit(1); }
}
/* -------------------------------------------------------------------------
PatchMatch, using L2 distance between upright patches that translate only
------------------------------------------------------------------------- */
int patch_w = 7;
int pm_iters = 5;
int rs_max = INT_MAX;
#define XY_TO_INT(x, y) (((y)<<12)|(x)) //把x,y合成一个数，
#define INT_TO_X(v) ((v)&((1<<12)-1))
#define INT_TO_Y(v) ((v)>>12)
/* Measure distance between 2 patches with upper left corners (ax, ay) and (bx, by), terminating early if we exceed a cutoff distance.
You could implement your own descriptor here. */
int dist(BITMAP *a, BITMAP *b, int ax, int ay, int bx, int by, int cutoff=INT_MAX) {
int ans = 0;
for (int dy = 0; dy < patch_w; dy++) {
int *arow = &(*a)[ay+dy][ax];
int *brow = &(*b)[by+dy][bx];
for (int dx = 0; dx < patch_w; dx++) {
int ac = arow[dx];
int bc = brow[dx];
int dr = (ac&255)-(bc&255);
int dg = ((ac>>8)&255)-((bc>>8)&255);//???
int db = (ac>>16)-(bc>>16);
ans += dr*dr + dg*dg + db*db;
}
if (ans >= cutoff) { return cutoff; }
}
return ans;
}
void improve_guess(BITMAP *a, BITMAP *b, int ax, int ay, int &xbest, int &ybest, int &dbest, int bx, int by) {
int d = dist(a, b, ax, ay, bx, by, dbest);
if (d < dbest) {
dbest = d;
xbest = bx;
ybest = by;
}
}
/* Match image a to image b, returning the nearest neighbor field mapping a => b coords, stored in an RGB 24-bit image as (by<<12)|bx. */
void patchmatch(BITMAP *a, BITMAP *b, BITMAP *&ann, BITMAP *&annd) {
/* Initialize with random nearest neighbor field (NNF). */
ann = new BITMAP(a->w, a->h);
annd = new BITMAP(a->w, a->h);
int aew = a->w - patch_w+1, aeh = a->h - patch_w + 1; /* Effective width and height (possible upper left corners of patches). */
int bew = b->w - patch_w+1, beh = b->h - patch_w + 1;
memset(ann->data, 0, sizeof(int)*a->w*a->h);//memset用于清空结构数据
memset(annd->data, 0, sizeof(int)*a->w*a->h);
for (int ay = 0; ay < aeh; ay++) {
for (int ax = 0; ax < aew; ax++) {
int bx = rand()%bew;
int by = rand()%beh;
(*ann)[ay][ax] = XY_TO_INT(bx, by);
(*annd)[ay][ax] = dist(a, b, ax, ay, bx, by);
}
}
for (int iter = 0; iter < pm_iters; iter++) {
/* In each iteration, improve the NNF, by looping in scanline or reverse-scanline order. */
int ystart = 0, yend = aeh, ychange = 1;
int xstart = 0, xend = aew, xchange = 1;
if (iter % 2 == 1) {//奇数次循环
xstart = xend-1; xend = -1; xchange = -1;
ystart = yend-1; yend = -1; ychange = -1;
}
for (int ay = ystart; ay != yend; ay += ychange) {
for (int ax = xstart; ax != xend; ax += xchange) {
/* Current (best) guess. */
int v = (*ann)[ay][ax];
int xbest = INT_TO_X(v), ybest = INT_TO_Y(v);
int dbest = (*annd)[ay][ax];
/* Propagation: Improve current guess by trying instead correspondences from left and above (below and right on odd iterations). */
if ((unsigned) (ax - xchange) < (unsigned) aew) {
int vp = (*ann)[ay][ax-xchange];
int xp = INT_TO_X(vp) + xchange, yp = INT_TO_Y(vp);//选取左相邻块的匹配块的右临近块比较
if ((unsigned) xp < (unsigned) bew) {
improve_guess(a, b, ax, ay, xbest, ybest, dbest, xp, yp);//选取距离较小的块，存储位置和距离在xbest, ybest, dbest中
}
}
if ((unsigned) (ay - ychange) < (unsigned) aeh) {
int vp = (*ann)[ay-ychange][ax];
int xp = INT_TO_X(vp), yp = INT_TO_Y(vp) + ychange;//选取上相邻块的匹配块的下临近块比较
if ((unsigned) yp < (unsigned) beh) {
improve_guess(a, b, ax, ay, xbest, ybest, dbest, xp, yp);
}
}
/* Random search: Improve current guess by searching in boxes of exponentially decreasing size around the current best guess. */
int rs_start = rs_max;
if (rs_start > MAX(b->w, b->h)) { rs_start = MAX(b->w, b->h); }
for (int mag = rs_start; mag >= 1; mag /= 2) {
/* Sampling window */ //在一定区域内随机搜索，并逐渐缩小区域范围
int xmin = MAX(xbest-mag, 0), xmax = MIN(xbest+mag+1,bew);
int ymin = MAX(ybest-mag, 0), ymax = MIN(ybest+mag+1,beh);
int xp = xmin+rand()%(xmax-xmin);
int yp = ymin+rand()%(ymax-ymin);
improve_guess(a, b, ax, ay, xbest, ybest, dbest, xp, yp);
}
(*ann)[ay][ax] = XY_TO_INT(xbest, ybest);
(*annd)[ay][ax] = dbest;
}
}
}
}
//vote
void voteimage(BITMAP *a, BITMAP *b, BITMAP *ann, BITMAP *&res)//res前面一定要加引用符号，否则改变不了
{
res = new BITMAP(a->w, a->h);
int aew = a->w - patch_w + 1, aeh = a->h - patch_w + 1;
memset(res->data, 0, sizeof(int)*a->w*a->h);//memset用于清空结构数据
for (int ay = 0; ay < aeh; ay++) {
for (int ax = 0; ax < aew; ax++) {
int v = (*ann)[ay][ax];
int xbest = INT_TO_X(v), ybest = INT_TO_Y(v);
(*res)[ay][ax] = (*b)[ybest][xbest];
}
}
}
//void save_res(BITMAP *bmp, const char *filename)
//{
// char rawname[256];
// strcpy(rawname, filename);
// if (!strstr(rawname, ".")) { fprintf(stderr, "Error writing image '%s': no extension found\n", filename); exit(1); }
// sprintf(strstr(rawname, "."), ".raw");//strstr查找子字符串
// char buf[256];
// FILE *f = fopen(rawname, "wb");
// if (!f) { fprintf(stderr, "Error writing image '%s': could not open raw temporary file\n", filename); exit(1); }
// int *p = (int *)bmp->data;
// for (int i = 0; i < bmp->w*bmp->h * 4; i++) {
// fputc(*p++, f);
// }
// fclose(f);
// sprintf(buf, "convert -size %dx%d -depth 8 rgba:%s %s", bmp->w, bmp->h, rawname, filename);
// if (system(buf) != 0) { fprintf(stderr, "Error writing image '%s': ImageMagick convert gave an error\n", filename); exit(1); }
// //FILE *fp = fopen("res.txt","wb");
// //for (int i = 0; i < bmp->w*bmp->h ; i++) {
// // fprintf(fp, "%d ", bmp[bmp->h][bmp->w]);
// //}
// //fclose(fp);
//}
void save_res1(BITMAP *bmp)
{
FILE *fp = fopen("res.txt","wb");
for (int i = 0; i < bmp->h; i++) {
for (int j = 0; j < bmp->w; j++) {
fprintf(fp, "%d ", (*bmp)[i][j]);
}
}
fclose(fp);
}
int main(int argc, char *argv[]) {
argc--;
argv++;
/* if (argc != 5) { fprintf(stderr, "pm_minimal a b ann annd\n"
"Given input images a, b outputs nearest neighbor field 'ann' mapping a => b coords, and the squared L2 distance 'annd'\n"
"These are stored as RGB 24-bit images, with a 24-bit int at every pixel. For the NNF we store (by<<12)|bx."); exit(1); }*/
printf("Loading input images\n");
BITMAP *a = load_bitmap(argv[0]);
BITMAP *b = load_bitmap(argv[1]);
BITMAP *ann = NULL, *annd = NULL;
BITMAP *res = NULL;
printf("Running PatchMatch\n");
patchmatch(a, b, ann, annd);
voteimage(a, b, ann, res);
printf("Saving output images\n");
save_bitmap(ann, argv[2]);
save_bitmap(annd, argv[3]);
save_res1(res);
save_bitmap(res, argv[4]);
return 0;
}
其中votemex和save_res函数是为了看效果加上的
在VS中编译后，找到EXE文件目录，调出cmd,运行如下程序
patchmatch_simple.exe a_gray.png b_gray.png a11.jpg b11.jpg c11.jpg
由于没有加上旋转，所以效果并不好，下面两张图分别为图a和图b
结果图如下
可以看到效果一般