diff options
Diffstat (limited to 'editor/specialty/ppmshift.c')
| -rw-r--r-- | editor/specialty/ppmshift.c | 235 |
1 files changed, 147 insertions, 88 deletions
diff --git a/editor/specialty/ppmshift.c b/editor/specialty/ppmshift.c index a765daa5..27cbb78c3 100644 --- a/editor/specialty/ppmshift.c +++ b/editor/specialty/ppmshift.c @@ -9,124 +9,183 @@ /* V1.1 16.11.1993 Rewritten to be NetPBM.programming conforming */ /*********************************************************************/ +#include <stdbool.h> + +#include "mallocvar.h" +#include "rand.h" +#include "shhopt.h" #include "ppm.h" -/**************************/ -/* start of main function */ -/**************************/ + +struct CmdlineInfo { + /* All the information the user supplied in the command line, + in a form easy for the program to use. + */ + const char * inputFileName; + + unsigned int shift; + unsigned int seedSpec; + unsigned int seed; +}; + + + +static void +parseCommandLine(int argc, const char ** const argv, + struct CmdlineInfo * const cmdlineP) { +/*---------------------------------------------------------------------------- + Note that the file spec array we return is stored in the storage that + was passed to us as the argv array. +-----------------------------------------------------------------------------*/ + optEntry * option_def; + /* Instructions to OptParseOptions3 on how to parse our options. */ + optStruct3 opt; + + unsigned int option_def_index; + + MALLOCARRAY(option_def, 100); + + opt.opt_table = option_def; + opt.short_allowed = false; /* We have no short (old-fashioned) options */ + opt.allowNegNum = true; /* We have no parms that are negative numbers */ + + option_def_index = 0; /* incremented by OPTENT3 */ + OPTENT3(0, "seed", OPT_UINT, &cmdlineP->seed, + &cmdlineP->seedSpec, 0); + + pm_optParseOptions3(&argc, (char **)argv, opt, sizeof(opt), 0); + /* Uses and sets argc, argv, and some of *cmdlineP and others. */ + + if (argc-1 < 1) + pm_error("You must specify the shift factor as an argument"); + else { + int const arg1 = atoi(argv[1]); + if (arg1 < 0) + pm_error("shift factor must be 0 or more"); + cmdlineP->shift = arg1; + + if (argc-1 < 2) + cmdlineP->inputFileName = "-"; + else { + cmdlineP->inputFileName = argv[2]; + + if (argc-1 > 2) + pm_error("Too many arguments (%u). " + "Shift factor and input file name are the only " + "possible arguments", argc-1); + } + } + free(option_def); +} + + + +static void +shiftRow(pixel * const srcrow, + unsigned int const cols, + unsigned int const shift, + pixel * const destrow, + struct pm_randSt * const randStP) { + + /* the range by which a line is shifted lays in the range from */ + /* -shift/2 .. +shift/2 pixels; however, within this range it is */ + /* randomly chosen */ + + pixel * pP; + pixel * pP2; + int nowshift; + + if (shift != 0) + nowshift = (pm_rand(randStP) % (shift+1)) - ((shift+1) / 2); + else + nowshift = 0; + + pP = &srcrow[0]; + pP2 = &destrow[0]; + + /* if the shift value is less than zero, we take the original + pixel line and copy it into the destination line translated + to the left by x pixels. The empty pixels on the right end + of the destination line are filled up with the pixel that + is the right-most in the original pixel line. + */ + if (nowshift < 0) { + unsigned int col; + pP += abs(nowshift); + for (col = 0; col < cols; ++col) { + PPM_ASSIGN(*pP2, PPM_GETR(*pP), PPM_GETG(*pP), PPM_GETB(*pP)); + ++pP2; + if (col < (cols + nowshift) - 1) + ++pP; + } + } else { + unsigned int col; + /* The shift value is 0 or positive, so fill the first + <nowshift> pixels of the destination line with the + first pixel from the source line, and copy the rest of + the source line to the dest line + */ + for (col = 0; col < cols; ++col) { + PPM_ASSIGN(*pP2, PPM_GETR(*pP), PPM_GETG(*pP), PPM_GETB(*pP)); + ++pP2; + if (col >= nowshift) + ++pP; + } + } +} + + + int -main(int argc, - char * argv[]) { +main(int argc, const char ** argv) { FILE * ifP; - unsigned int row; - int argn, rows, cols, format; + struct CmdlineInfo cmdline; + int rows, cols, format; + pixval maxval; pixel * srcrow; pixel * destrow; - pixval maxval; - int shift, nowshift; - int shiftArg; - - const char * const usage = "shift [ppmfile]\n shift: maximum number of pixels to shift a line by\n"; + unsigned int row; + unsigned int shift; + struct pm_randSt randSt; /* parse in 'default' parameters */ - ppm_init(&argc, argv); - - argn = 1; - - /* parse in shift number */ - if (argn == argc) - pm_usage(usage); - if (sscanf(argv[argn], "%d", &shiftArg) != 1) - pm_usage(usage); - if (shiftArg < 0) - pm_error("shift factor must be 0 or more"); - ++argn; - - /* parse in filename (if present, stdin otherwise) */ - if (argn != argc) - { - ifP = pm_openr(argv[argn]); - ++argn; - } - else - ifP = stdin; + pm_proginit(&argc, argv); + + parseCommandLine(argc, argv, &cmdline); + + pm_randinit(&randSt); + pm_srand2(&randSt, cmdline.seedSpec, cmdline.seed); - if (argn != argc) - pm_usage(usage); + ifP = pm_openr(cmdline.inputFileName); /* read first data from file */ ppm_readppminit(ifP, &cols, &rows, &maxval, &format); - if (shiftArg > cols) { + if (cmdline.shift > cols) { shift = cols; - pm_message("shift amount is larger than picture width - reset to %d", + pm_message("shift amount is larger than picture width - reset to %u", shift); } else - shift = shiftArg; - - srcrow = ppm_allocrow(cols); + shift = cmdline.shift; + srcrow = ppm_allocrow(cols); destrow = ppm_allocrow(cols); ppm_writeppminit(stdout, cols, rows, maxval, 0); - srand(pm_randseed()); - - /** now do the shifting **/ - /* the range by which a line is shifted lays in the range from */ - /* -shift/2 .. +shift/2 pixels; however, within this range it is */ - /* randomly chosen */ for (row = 0; row < rows; ++row) { - pixel * pP; - pixel * pP2; - - if (shift != 0) - nowshift = (rand() % (shift+1)) - ((shift+1) / 2); - else - nowshift = 0; - ppm_readppmrow(ifP, srcrow, cols, maxval, format); - pP = &srcrow[0]; - pP2 = &destrow[0]; - - /* if the shift value is less than zero, we take the original - pixel line and copy it into the destination line translated - to the left by x pixels. The empty pixels on the right end - of the destination line are filled up with the pixel that - is the right-most in the original pixel line. - */ - if (nowshift < 0) { - unsigned int col; - pP += abs(nowshift); - for (col = 0; col < cols; ++col) { - PPM_ASSIGN(*pP2, PPM_GETR(*pP), PPM_GETG(*pP), PPM_GETB(*pP)); - ++pP2; - if (col < (cols + nowshift) - 1) - ++pP; - } - } else { - unsigned int col; - /* The shift value is 0 or positive, so fill the first - <nowshift> pixels of the destination line with the - first pixel from the source line, and copy the rest of - the source line to the dest line - */ - for (col = 0; col < cols; ++col) { - PPM_ASSIGN(*pP2, PPM_GETR(*pP), PPM_GETG(*pP), PPM_GETB(*pP)); - ++pP2; - if (col >= nowshift) - ++pP; - } - } + shiftRow(srcrow, cols, shift, destrow, &randSt); ppm_writeppmrow(stdout, destrow, cols, maxval, 0); } - pm_close(ifP); - ppm_freerow(srcrow); ppm_freerow(destrow); + ppm_freerow(srcrow); + pm_close(ifP); + pm_randterm(&randSt); return 0; } |