diff options
| -rw-r--r-- | converter/other/pbmtopgm.c | 147 |
1 files changed, 90 insertions, 57 deletions
diff --git a/converter/other/pbmtopgm.c b/converter/other/pbmtopgm.c index 72a2afff..b9762e26 100644 --- a/converter/other/pbmtopgm.c +++ b/converter/other/pbmtopgm.c @@ -9,85 +9,118 @@ #include "nstring.h" #include "pgm.h" -int -main(int argc, char *argv[]) { - gray *outrow, maxval; - int right, left, down, up; - bit **inbits; - int rows, cols; - FILE *ifd; - int row; - unsigned int width, height; - const char * const usage = "<w> <h> [pbmfile]"; - const char * error; /* error message of pm_string_to_uint */ - pgm_init( &argc, argv ); +struct CmdlineInfo { + unsigned int convCols; + unsigned int convRows; + const char * inputFileName; +}; + + + +static void +parseCommandLine(int const argc, + const char ** const argv, + struct CmdlineInfo * const cmdlineP) { + + const char * error; /* error message from pm_string_to_uint */ + + if (argc-1 < 2) + pm_error("Insufficient arguments (%d). Need width and height " + "of convolution kernel, in pixels", argc-1); + else { + pm_string_to_uint(argv[1], &cmdlineP->convCols, &error); + if (error) + pm_error("Invalid convolution kernel width argument. %s", error); + + pm_string_to_uint(argv[2], &cmdlineP->convRows, &error); + if (error) + pm_error("Invalid convolution kernel height argument. %s", error); + if (cmdlineP->convCols < 1 || cmdlineP->convRows < 1) + pm_error("convolution kernel width and height must be > 0"); + + if (argc-1 >= 3) + cmdlineP->inputFileName = argv[3]; + else { + cmdlineP->inputFileName = "'"; + + if (argc-1 > 3) + pm_error("Too many arguments (%d). The most possible are " + "convolution kernel width and height " + "and input file name", argc-1); + } + } +} + + - if (argc > 4 || argc < 3) - pm_usage(usage); +int +main(int argc, const char ** argv) { - pm_string_to_uint(argv[1], &width, &error); - if (error) - pm_error("Invalid width argument: %s", error); - pm_string_to_uint(argv[2], &height, &error); - if (error) - pm_error("Invalid height argument: %s", error); - if (width < 1 || height < 1) - pm_error("width and height must be > 0"); + struct CmdlineInfo cmdline; + gray * outrow; + gray maxval; + unsigned int right, left, down, up; + bit ** inbits; + int rows, cols; + FILE * ifP; + unsigned int row; - if (argc == 4) - ifd = pm_openr(argv[3]); - else - ifd = stdin ; + pm_proginit(&argc, argv); - inbits = pbm_readpbm(ifd, &cols, &rows) ; + parseCommandLine(argc, argv, &cmdline); - if (width > cols) - pm_error("You specified a sample width (%u columns) which is greater " - "than the image width (%u columns)", width, cols); - if (height > rows) - pm_error("You specified a sample height (%u rows) which is greater " - "than the image height (%u rows)", height, rows); - if (width > INT_MAX / height) - /* prevent overflow of "value" below */ - pm_error("sample area (%u columns %u rows) too large", - width, height); + ifP = pm_openr(cmdline.inputFileName); - left = width / 2; right = width - left; - up = height / 2; down = height - up; + inbits = pbm_readpbm(ifP, &cols, &rows); + if (cmdline.convCols > cols) + pm_error("You specified a convolution kernel width (%u columns) " + "which is greater than the image width (%u columns)", + cmdline.convCols, cols); + if (cmdline.convRows > rows) + pm_error("You specified a convolution kernel height (%u rows) " + "which is greater than the image height (%u rows)", + cmdline.convRows, rows); + left = cmdline.convCols / 2; right = cmdline.convCols - left; + up = cmdline.convRows / 2; down = cmdline.convRows - up; outrow = pgm_allocrow(cols) ; - maxval = MIN(PGM_OVERALLMAXVAL, width*height); + maxval = MIN(PGM_OVERALLMAXVAL, cmdline.convCols * cmdline.convRows); pgm_writepgminit(stdout, cols, rows, maxval, 0) ; - for (row = 0; row < rows; row++) { - int const t = (row > up) ? (row-up) : 0; - int const b = (row+down < rows) ? (row+down) : rows; - int const onv = height - (t-row+up) - (row+down-b); + for (row = 0; row < rows; ++row) { + unsigned int const t = (row > up) ? (row - up) : 0; + unsigned int const b = (row + down < rows) ? (row + down) : rows; + unsigned int const actualConvRows = + cmdline.convRows - (t - row + up) - (row + down - b); unsigned int col; - for (col = 0; col < cols; col++) { - int const l = (col > left) ? (col-left) : 0; - int const r = (col+right < cols) ? (col+right) : cols; - int const onh = width - (l-col+left) - (col+right-r); - int value; /* See above */ - int x; - - value = 0; /* initial value */ - - for (x = l; x < r; ++x) { - int y; + for (col = 0; col < cols; ++col) { + unsigned int const l = (col > left) ? (col - left) : 0; + unsigned int const r = (col + right < cols) ? (col + right) : cols; + unsigned int const actualConvCols = + cmdline.convCols - (l - col + left) - (col + right - r); + unsigned int value; + unsigned int x; + + for (x = l, value = 0; x < r; ++x) { + unsigned int y; for (y = t; y < b; ++y) if (inbits[y][x] == PBM_WHITE) ++value; } - outrow[col] = (gray) ((double) maxval*value/(onh*onv)); + { + unsigned int const convKernelArea = + actualConvRows * actualConvCols; + outrow[col] = (gray) (((double) value/convKernelArea)*maxval); + } } pgm_writepgmrow(stdout, outrow, cols, maxval, 0) ; } - pm_close(ifd); + pbm_freearray(inbits, rows); + pm_close(ifP); return 0; } |