/*! \fn int gaussPGM(Pgm* pgmIn, Pgm* pgmOut, double sigma, int dim)
* \brief Gaussian blur of an image \a pgmIn.
*
* Apply as a filter two 1D Gaussian filters with the same \a sigma and matrix linear dimension \a dim.
* \param pgmIn Pointer to the input Pgm image structure.
* \param pgmOut Pointer to the output Pgm image structure.
* \param sigma The sigma of the gaussians.
* \param dim The dimension of the gaussian filter. If 0 it will default to the nearest odd value close to 6 sigma.
* \return 0 on success, -1 if either pgmIn or pgmOut are NULL.
*/
int gaussPGM(Pgm* pgmIn, Pgm* pgmOut, double sigma, int dim)
{
if(!pgmIn)
{
fprintf(stderr, "Error! No input data. Please Check.\n");
return -1;
}
if(!pgmOut)
{
fprintf(stderr, "Error! No space to store the result. Please Check.\n");
return -1;
}
Filter* filter;
Pgm* imgOut1 = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
// linear X guassian filter
filter = gauss1DXFilter(sigma, dim);
convolution1DXPGM(pgmIn, imgOut1, filter);
freeFilter(&filter);
// linear Y guassian filter
filter = gauss1DYFilter(sigma, dim);
convolution1DYPGM(imgOut1, pgmOut, filter);
freeFilter(&filter);
freePGM(&imgOut1);
return 0;
}
/*! \fn cedPGM(Pgm* pgmIn, Pgm* pgmOut, double sigma, int dim, int threshold_low, int threshold_high)
* \brief Filter the image \a pgmIn with two Prewitt filters alogn the vertical and horizontal direction.
* Returns either the magnitute or the phase based on \a phase.
*
* Apply the vertical and horizontal Prewitt filters and returns the magnitute if \a phase is 0
* or the phase if \a phase is 1.
* \param pgmIn Pointer to the input PGM image structure.
* \param pgmOut Pointer to the output PGM image structure.
* \param sigma The external sigma of the DoG filter. The internal sigma is set to \a sigma / 1.66 .
* \param dim The rows and columns of the DoG filter. If set to 0 then it will be the smallest odd next to 6 \a sigma.
* \param threshold_low Lower threshold used by the Canny algorithm.
* \param threshold_high Hihger threshold used by the Canny algorithm.
* \return 0 on success, -1 if either pgmIn or pgmOut are NULL.
*/
int cedPGM(Pgm* pgmIn, Pgm* pgmOut, double sigma, int dim, int threshold_low, int threshold_high)
{
int i;
Pgm* imgOutX = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
Pgm* imgOutY = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
Pgm* imgOutMod = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
Pgm* imgOutPhi = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
gaussPGM(pgmIn, pgmOut, sigma, dim);
Filter* gx = sobelXFilter();
Filter* gy = sobelYFilter();
convolution2DPGM(pgmOut, imgOutX, gx);
convolution2DPGM(pgmOut, imgOutY, gy);
modulePGM(imgOutX, imgOutY, imgOutMod);
phasePGM(imgOutX, imgOutY, imgOutPhi);
resetPGM(pgmOut);
suppressionPGM(imgOutMod, imgOutPhi, pgmOut);
freePGM(&imgOutX);
freePGM(&imgOutY);
freePGM(&imgOutMod);
freePGM(&imgOutPhi);
// Find strong and weak edges with thresholding
Pgm *imgNH = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
thresholdPGM(pgmOut, imgNH, threshold_high);
Pgm *imgNLshadow = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
thresholdPGM(pgmOut, imgNLshadow, threshold_low);
Pgm *imgNL = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
linearAddPGM(imgNLshadow, imgNH, 1.0, -1.0, imgNL);
int change = 1;
// Find 8-connected pixels in imgNL by a repeated search
for (i=0; (i<50) && change; i++) {
connectivityPGM(imgNH, imgNL, pgmOut);
change = comparePGM(imgNH, pgmOut);
copyPGM(pgmOut, imgNH);
}
copyPGM(imgNH, pgmOut);
freePGM(&imgNLshadow);
freePGM(&imgNH);
freePGM(&imgNL);
return 0;
}
/*! \fn int prewittPGM(Pgm* pgmIn, Pgm* pgmOut, uint8_t phase)
* \brief Filter the image \a pgmIn with two Prewitt filters alogn the vertical and horizontal direction.
* Returns either the magnitute or the phase based on \a phase.
*
* Apply the vertical and horizontal Prewitt filters and returns the magnitute if \a phase is 0
* or the phase if \a phase is 1.
* \param pgmIn Pointer to the input PGM image structure.
* \param pgmOut Pointer to the output PGM image structure.
* \param phase Returns the phase if set to 1. Otherwise it returns the magnitude.
* \return 0 on success, -1 if either pgmIn or pgmOut are NULL.
*/
int prewittPGM(Pgm* pgmIn, Pgm* pgmOut, unsigned int phase)
{
if(!pgmIn)
{
fprintf(stderr, "Error! No input data. Please Check.\n");
return -1;
}
if(!pgmOut)
{
fprintf(stderr, "Error! No space to store the result. Please Check.\n");
return -1;
}
Filter* filter;
Pgm* gx = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
// apply a sobel horizontal filter
filter = prewittXFilter();
convolution2DPGM(pgmIn, gx, filter);
freeFilter(&filter);
Pgm* gy = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
// apply a sobel vertical filter
filter = prewittYFilter();
convolution2DPGM(pgmIn, gy, filter);
freeFilter(&filter);
// compute the module of the two images with the
// applied sobel filters
resetPGM(pgmOut);
if (phase == 0) {
modulePGM(gx, gy, pgmOut);
} else
phasePGM(gx, gy, pgmOut);
freePGM(&gx);
freePGM(&gy);
return 0;
}
/*! \fn execImageOps(Pgm *pgmIn, Pgm* pgmOut, FILE *fp)
* \brief Filter the image \a pgmIn with the filters listed in file \a fp.
*
* The file \a fp contains a list of filters, one per line, that will be applied in sequence to
* the image pointed by \a pgmIn. The output will be stored in the Pgm structure pointed by
* \a pgmOut. Certain filters have optional parameters.
*
* \param pgmIn Pointer to the input PGM image structure.
* \param pgmOut Pointer to the output PGM image structure.
* \param fp Pointer to a file with the list of filters.
*
* \par List of implemented filters
*
* - threshold [threshold_value (default 0)]
* - uniform_noise [range_value (default 32)]
* - salt_n_pepper [density (default 0.05)]
* - normalize
* - equalize
* - median
* - average
* - internal_contour
* - operator_39
* - nagao
* - sharpening
* - prewitt [mod|phase (default mod)]
* - sobel [mod|phase (default mod)]
* - gauss [sigma (default 1)] [dim (default 0)]
* - dog [sigma (default 1)] [dim (default 0)]
* - ced [sigma (default sqrt(2))] [threshold (default 25)]
*/
void execImageOps(Pgm *pgmIn, Pgm* pgmOut, FILE *fp)
{
char buffer[64];
char *ch, *cmdline;
int iarg;
float farg;
Pgm* pgmTmp = newPGM(pgmIn->width, pgmIn->height, pgmIn->max_val);
copyPGM(pgmIn, pgmOut);
while (fgets(buffer,sizeof(buffer),fp)!=NULL) {
copyPGM(pgmOut, pgmTmp);
// Read a line till \n or 64 char
cmdline = trimwhitespace(buffer);
ch = strtok(cmdline, " ");
if (strcmp(ch,"threshold")==0) {
ch = strtok(NULL, " ");
if (ch == NULL) {
iarg = 0;
} else
iarg = atoi(ch);
thresholdPGM(pgmTmp, pgmOut, iarg);
} else if (strcmp(ch,"uniform_noise")==0) {
ch = strtok(NULL, " ");
if (ch == NULL) {
iarg = 32;
} else
iarg = atoi(ch);
addUniformNoisePGM(pgmTmp, pgmOut, iarg);
} else if (strcmp(ch,"salt_n_pepper")==0) {
ch = strtok(NULL, " ");
if (ch == NULL) {
farg = 0.05;
} else
sscanf(ch,"%f",&farg);
addSaltPepperNoisePGM(pgmTmp, pgmOut, farg);
} else if (strcmp(ch,"normalize")==0) {
normalizePGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"equalize")==0) {
equalizePGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"median")==0) {
fprintf(stderr,"Start median\n");
medianPGM(pgmTmp, pgmOut);
fprintf(stderr,"Median completed\n");
} else if (strcmp(ch,"average")==0) {
averagePGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"internal_contour")==0) {
contourN8IntPGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"operator_39")==0) {
op39PGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"nagao")==0) {
nagaoPGM(pgmTmp, pgmOut);
} else if (strcmp(ch,"sharpening")==0) {
sharpeningPGM(pgmTmp, pgmOut);
} else if (strcmp(ch, "prewitt")==0) {
ch = strtok(NULL, " ");
if (ch==NULL) {
iarg = 0;
} else
if (strcmp(ch, "phase") == 0) {
iarg = 1;
}
else
iarg = 0;
prewittPGM(pgmTmp, pgmOut, iarg);
} else if (strcmp(ch, "sobel")==0) {
ch = strtok(NULL, " ");
if (ch==NULL) {
iarg = 0;
} else
if (strcmp(ch, "phase") == 0) {
iarg = 1;
}
else
iarg = 0;
sobelPGM(pgmTmp, pgmOut, iarg);
} else if (strcmp(ch, "gauss")==0) {
ch = strtok(NULL, " ");
if (ch==NULL) {
farg = 1.0;
iarg = 0;
} else
sscanf(ch, "%f", &farg);
ch = strtok(NULL, " ");
if ( ch == NULL) {
iarg = 0;
}
else
iarg = atoi(ch);
gaussPGM(pgmTmp, pgmOut, farg, iarg);
} else if (strcmp(ch, "dog")==0) {
ch = strtok(NULL, " ");
if (ch==NULL) {
farg = 1.0;
iarg = 0;
} else
sscanf(ch, "%f", &farg);
ch = strtok(NULL, " ");
if ( ch == NULL) {
iarg = 0;
}
else
iarg = atoi(ch);
dogPGM(pgmTmp, pgmOut, farg, iarg);
} else if (strcmp(ch, "ced")==0) {
ch = strtok(NULL, " ");
if (ch==NULL) {
farg = sqrt(2.0);
iarg = 0;
} else
sscanf(ch, "%f", &farg);
ch = strtok(NULL, " ");
if ( ch == NULL) {
iarg = 25;
}
else
iarg = atoi(ch);
cedPGM(pgmTmp, pgmOut, farg, 0, iarg, iarg*3);
}
}
freePGM(&pgmTmp);
return;
}
int main(int argc, char *argv[]) {
imagePGM srcImg;
imagePGM dstImg;
char *srcFilename;
char *dstFilename;
int FileLoad = 0, FileLoadFilename = 0, FileSave = 0, FileSaveFilename = 0, flagInfo = 0, FileInfoOptions = 0;
int FileImage = 0, FileImageOptions = 0, rotAngle = 0;
int c;
int index;
while ((c = getopt(argc, argv, "i:o:hnr:")) != -1) {
switch (c) {
case 'h':
printHelp();
exit(EXIT_SUCCESS);
case 'n':
flagInfo = 1;
break;
case 'i':
FileLoad = 1;
FileLoadFilename = 1;
srcFilename = optarg;
break;
case 'o':
FileSave = 1;
FileSaveFilename = 1;
dstFilename = optarg;
break;
case 'r':
FileImage = 1;
FileImageOptions = 1;
rotAngle = atoi(optarg);
break;
case '?':
break;
/*
if (optopt == 'i')
fprintf(stderr, "Option -%c requires an argument.\n", optopt);
else if (optopt == 'o')
fprintf(stderr, "Option -%c requires an argument.\n", optopt);
else if (optopt == 'r')
fprintf(stderr, "Option -%c requires an argument.\n", optopt);
else if (isprint(optopt))
fprintf(stderr, "Unknown option `-%c'.\n", optopt);
else
fprintf(stderr, "Unknown option character `\\x%x'.\n", optopt);
return 1;
*/
default:
fprintf(stderr, "Wrong arguments. try simpleocr -h for help.");
exit(EXIT_FAILURE);
}
}
///printf("src = %s\n", dstFilename);
if (FileLoad && FileLoadFilename) {
srcImg = loadPGM(srcFilename);
if (flagInfo) {
printf ("Properties:\n");
printf ("format: %s\n", getFormatPGM(srcImg));
printf ("depth: %d\n", getMaxIntensityPGM(srcImg));
printf ("width: %d\n", getColsPGM(srcImg));
printf ("height: %d\n", getRowsPGM(srcImg));
printf ("###: %d\n", getRowsPGM(srcImg));
dstImg = buildHistogram(srcImg);
savePGM("histogram.pgm", dstImg);
}
}
if (FileSave && FileSaveFilename) {
if (FileImage) {
dstImg = rotatePGM(srcImg, rotAngle);
}
savePGM(dstFilename, dstImg);
freePGM(dstImg);
printf ("Done\n");
}
return 0;
}
