/**
* Select pivot index to use in partition. Select median of medians.
*
* \param vals the array of elements.
* \param left the left end of the subarray range
* \param right the right end of the subarray range
* \return int in the range [left, right] to use in partition.
*/
int selectPivotIndex (void **vals, int left, int right) {
return selectMedian (vals, &ascending, left, right);
}
int
main(int argc,
char * argv[]) {
struct cmdlineInfo cmdline;
FILE * ifP;
int cols, rows;
int median;
enum medianMethod medianMethod;
pgm_init(&argc, argv);
parseCommandLine(argc, argv, &cmdline);
ifP = pm_openr(cmdline.inputFileName);
ccolso2 = cmdline.width / 2;
crowso2 = cmdline.height / 2;
pgm_readpgminit(ifP, &cols, &rows, &maxval, &format);
pgm_writepgminit(stdout, cols, rows, maxval, forceplain);
/* Allocate space for number of rows in mask size. */
grays = pgm_allocarray(cols, cmdline.height);
grayrow = pgm_allocrow(cols);
/* Read in and write out initial rows that won't get changed. */
for (row = 0; row < cmdline.height - 1; ++row) {
pgm_readpgmrow(ifP, grays[row], cols, maxval, format);
/* Write out the unchanged row. */
if (row < crowso2)
pgm_writepgmrow(stdout, grays[row], cols, maxval, forceplain);
}
median = (cmdline.height * cmdline.width) / 2;
/* Choose which sort to run. */
if (cmdline.type == MEDIAN_UNSPECIFIED) {
if ((maxval / ((cmdline.width * cmdline.height) - 1)) < cmdline.cutoff)
medianMethod = HISTOGRAM_SORT_MEDIAN;
else
medianMethod = SELECT_MEDIAN;
} else
medianMethod = cmdline.type;
switch (medianMethod) {
case SELECT_MEDIAN:
selectMedian(ifP, cmdline.width, cmdline.height, cols, rows, median);
break;
case HISTOGRAM_SORT_MEDIAN:
histogramSortMedian(ifP, cmdline.width, cmdline.height,
cols, rows, median);
break;
case MEDIAN_UNSPECIFIED:
pm_error("INTERNAL ERROR: median unspecified");
}
pm_close(ifP);
pm_close(stdout);
pgm_freearray(grays, cmdline.height);
pgm_freerow(grayrow);
return 0;
}
