/*============================================================================= pbmtolps =============================================================================== Convert a PBM image to Postscript. The output Postscript uses lines instead of the image operator to generate a (device dependent) picture which will be imaged much faster. The Postscript path length is constrained to be at most 1000 vertices so that no limits are overrun on the Apple Laserwriter and (presumably) no other printers. The typical limit is 1500. See "4.4 Path Construction" and "Appendix B: Implementation Limits" in: PostScript Language Reference Manual https://www.adobe.com/content/dam/acom/en/devnet/actionscript/ articles/psrefman.pdf To do: make sure encapsulated format is correct repetition of black-white strips make it more device independent (is this possible?) Author: George Phillips Department of Computer Science University of British Columbia =============================================================================*/ #include #include "pm_c_util.h" #include "mallocvar.h" #include "nstring.h" #include "shhopt.h" #include "pbm.h" static float const MAX_DPI = 5000; static float const MIN_DPI = 10; static unsigned int const MAX_PATH_VERTICES = 1000; struct CmdlineInfo { /* All the information the user supplied in the command line, in a form easy for the program to use. */ const char * inputFileName; /* File name of input file */ unsigned int inputFileSpec; /* Input file name specified */ float lineWidth; /* Line width, if specified */ unsigned int lineWidthSpec; /* Line width specified */ float dpi; /* Resolution in DPI, if specified */ unsigned int dpiSpec; /* Resolution specified */ }; static void validateDpi(float const dpi) { if (dpi > MAX_DPI || dpi < MIN_DPI) pm_error("Specified DPI value out of range (%f)", dpi); } static void parseCommandLine(int argc, const char ** const argv, struct CmdlineInfo * const cmdlineP) { /*---------------------------------------------------------------------------- Parse program command line described in Unix standard form by argc and argv. Return the information in the options as *cmdlineP. -----------------------------------------------------------------------------*/ optEntry * option_def; /* malloc'ed */ /* Instructions to OptParseOptions3 on how to parse our options. */ optStruct3 opt; unsigned int option_def_index; MALLOCARRAY_NOFAIL(option_def, 100); option_def_index = 0; /* incremented by OPTENTRY */ OPTENT3(0, "linewidth", OPT_FLOAT, &cmdlineP->lineWidth, &cmdlineP->lineWidthSpec, 0); OPTENT3(0, "dpi", OPT_FLOAT, &cmdlineP->dpi, &cmdlineP->dpiSpec, 0); opt.opt_table = option_def; opt.short_allowed = FALSE; /* We have no short (old-fashioned) options */ opt.allowNegNum = FALSE; /* We have no parms that are negative numbers */ pm_optParseOptions3(&argc, (char **)argv, opt, sizeof(opt), 0); /* Uses and sets argc, argv, and some of *cmdlineP and others. */ if (cmdlineP->dpiSpec) validateDpi(cmdlineP->dpi); else cmdlineP->dpi = 300; if (argc-1 < 1) cmdlineP->inputFileName = "-"; else { if (argc-1 > 1) pm_error("Program takes zero or one argument (filename). You " "specified %u", argc-1); else cmdlineP->inputFileName = argv[1]; } if (cmdlineP->inputFileName[0] == '-' && cmdlineP->inputFileName[1] == '\0') cmdlineP->inputFileSpec = false; else cmdlineP->inputFileSpec = true; free(option_def); } static void validateLineWidth(float const scCols, float const scRows, float const lineWidth) { if (lineWidth >= scCols || lineWidth >= scRows) pm_error("Absurdly large -linewidth value (%f)", lineWidth); } static void doRaster(FILE * const ifP, unsigned int const cols, unsigned int const rows, int const format, FILE * const ofP) { bit * bitrow; unsigned int row; unsigned int vertexCt; /* Number of vertices drawn since last stroke command */ bitrow = pbm_allocrow(cols); for (row = 0, vertexCt = 0; row < rows; ++row) { unsigned int col; bool firstRun; firstRun = true; /* initial value */ pbm_readpbmrow(ifP, bitrow, cols, format); /* output white-strip + black-strip sequences */ for (col = 0; col < cols; ) { unsigned int whiteCt; unsigned int blackCt; for (whiteCt = 0; col < cols && bitrow[col] == PBM_WHITE; ++col) ++whiteCt; for (blackCt = 0; col < cols && bitrow[col] == PBM_BLACK; ++col) ++blackCt; if (blackCt > 0) { if (vertexCt > MAX_PATH_VERTICES) { printf("m "); vertexCt = 0; } if (firstRun) { printf("%u %u moveto %u 0 rlineto\n", whiteCt, row, blackCt); firstRun = false; } else printf("%u %u a\n", blackCt, whiteCt); vertexCt += 2; } } } pbm_freerow(bitrow); } static void pbmtolps(FILE * const ifP, FILE * const ofP, struct CmdlineInfo const cmdline) { const char * const psName = cmdline.inputFileSpec ? cmdline.inputFileName : "noname"; int rows; int cols; int format; float scRows, scCols; /* Dimensions of the printed image in points */ pbm_readpbminit(ifP, &cols, &rows, &format); scRows = (float) rows / (cmdline.dpi / 72.0); scCols = (float) cols / (cmdline.dpi / 72.0); if (cmdline.lineWidthSpec) validateLineWidth(scCols, scRows, cmdline.lineWidth); fputs("%!PS-Adobe-2.0 EPSF-2.0\n", ofP); fputs("%%Creator: pbmtolps\n", ofP); fprintf(ofP, "%%%%Title: %s\n", psName); fprintf(ofP, "%%%%BoundingBox: %d %d %d %d\n", (int)(305.5 - scCols / 2.0), (int)(395.5 - scRows / 2.0), (int)(306.5 + scCols / 2.0), (int)(396.5 + scRows / 2.0)); fputs("%%EndComments\n", ofP); fputs("%%EndProlog\n", ofP); fputs("gsave\n", ofP); fprintf(ofP, "%f %f translate\n", 306.0 - scCols / 2.0, 396.0 + scRows / 2.0); fprintf(ofP, "72 %f div dup neg scale\n", cmdline.dpi); if (cmdline.lineWidthSpec) fprintf(ofP, "%f setlinewidth\n", cmdline.lineWidth); fputs("/a { 0 rmoveto 0 rlineto } def\n", ofP); fputs("/m { currentpoint stroke newpath moveto } def\n", ofP); fputs("newpath 0 0 moveto\n", ofP); doRaster(ifP, cols, rows, format, ofP); fputs("stroke grestore showpage\n", ofP); fputs("%%Trailer\n", ofP); } int main(int argc, const char *argv[]) { FILE * ifP; struct CmdlineInfo cmdline; pm_proginit(&argc, argv); parseCommandLine(argc, argv, &cmdline); ifP = pm_openr(cmdline.inputFileName); pbmtolps(ifP, stdout, cmdline); pm_close(ifP); return 0; }