/* Read keypoints from the given file pointer and return the list of
* keypoints. The file format starts with 2 integers giving the total
* number of keypoints and the size of descriptor vector for each
* keypoint (currently assumed to be 128). Then each keypoint is
* specified by 4 floating point numbers giving subpixel row and
* column location, scale, and orientation (in radians from -PI to
* PI). Then the descriptor vector for each keypoint is given as a
* list of integers in range [0,255]. */
std::vector<Keypoint> ReadKeys(FILE *fp, bool descriptor)
{
int i, j, num, len, val;
std::vector<Keypoint> kps;
if (fscanf(fp, "%d %d", &num, &len) != 2) {
printf("Invalid keypoint file beginning.");
return kps;
}
#ifdef KEY_LIMIT
num = MIN(num, 65536); // we'll store at most 65536 features per
// image
#endif /* KEY_LIMIT */
if (len != 128) {
printf("Keypoint descriptor length invalid (should be 128).");
return kps;
}
for (i = 0; i < num; i++) {
/* Allocate memory for the keypoint. */
unsigned char *d = new unsigned char[len];
float x, y, scale, ori;
if (fscanf(fp, "%f %f %f %f", &y, &x, &scale, &ori) != 4) {
printf("Invalid keypoint file format.");
return kps;
}
for (j = 0; j < len; j++) {
if (fscanf(fp, "%d", &val) != 1 || val < 0 || val > 255) {
printf("Invalid keypoint file value.");
return kps;
}
d[j] = (unsigned char) val;
}
if (descriptor) {
kps.push_back(KeypointWithDesc(x, y, d));
} else {
delete [] d;
kps.push_back(Keypoint(x, y));
}
}
return kps;
}
void CensureDetector::FindKeypoints(std::vector<Keypoint>& v)
{
for(int lv=0;lv<7;lv++)
{
int margin = extFilterSize[lv+1>6?6:lv+1]/2;
for(int i=margin;i<bufy-margin;i++)
{
for(int j=margin;j<bufx-margin;j++)
{
if(IsLocalExtremum(j,i,lv,param.nonMaxSuppThreshold))
{
// if(HarrisTest(j, i, lv, param.harrisThreshold))
// {
v.push_back(Keypoint(j,i,lv, filterResponse[lv][i*bufx+j]));
// }
}
}
}
}
}
/* Read keys using MMAP to speed things up */
std::vector<Keypoint> ReadKeysMMAP(FILE *fp)
{
int i, j, num, len, val, n;
std::vector<Keypoint> kps;
struct stat sb;
/* Stat the file */
if (fstat(fileno(fp), &sb) < 0) {
printf("[ReadKeysMMAP] Error: could not stat file\n");
return kps;
}
char *file = (char *)mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED,
fileno(fp), 0);
char *file_start = file;
char string_buf[1024];
char *str = string_buf;
/* Find the first '\n' */
char *newline = strchr(file, '\n');
int pos = (int) (newline - file);
memcpy(str, file, pos);
str[pos] = 0;
if (sscanf(str, "%d %d%n", &num, &len, &n) != 2) {
printf("[ReadKeysMMAP] Invalid keypoint file beginning.");
return kps;
}
#ifdef KEY_LIMIT
num = MIN(num, 65536); // we'll store at most 65536 features per
// image
#endif /* KEY_LIMIT */
file += (pos + 1);
if (len != 128) {
printf("[ReadKeysMMAP] Keypoint descriptor length invalid "
"(should be 128).");
return kps;
}
for (i = 0; i < num; i++) {
str = string_buf;
/* Allocate memory for the keypoint. */
unsigned char *d = new unsigned char[len];
float x, y, scale, ori;
/* Find the first '\n' */
newline = strchr(file, '\n');
pos = (int) (newline - file);
memcpy(str, file, pos);
str[pos] = 0;
if (sscanf(str, "%f %f %f %f%n", &y, &x, &scale, &ori, &n) != 4) {
printf("[ReadKeysMMAP] Invalid keypoint file format.");
return kps;
}
file += (pos + 1);
/* Find the next seven '\n's */
str = string_buf;
char *seventh_newline = strchrn(file, '\n', 7);
pos = (int) (seventh_newline - file);
memcpy(str, file, pos);
str[pos] = 0;
for (j = 0; j < len; j++) {
if (sscanf(str, "%d%n", &val, &n) != 1 || val < 0 || val > 255) {
printf("[ReadKeysMMAP] Invalid keypoint file value.");
return kps;
}
d[j] = (unsigned char) val;
str += n;
}
file += (pos + 1);
if (desc)
kps.Add(Keypoint(x, y, d));
else
kps.Add(Keypoint(x, y));
}
/* Unmap */
if (munmap(file_start, sb.st_size) < 0) {
printf("[ReadKeysMMAP] Error: could not unmap memory\n");
return kps;
}
return kps;
}
