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-rw-r--r--src/trace/potrace/greymap.cpp941
1 files changed, 0 insertions, 941 deletions
diff --git a/src/trace/potrace/greymap.cpp b/src/trace/potrace/greymap.cpp
deleted file mode 100644
index 4ef2ec8df..000000000
--- a/src/trace/potrace/greymap.cpp
+++ /dev/null
@@ -1,941 +0,0 @@
-/* Copyright (C) 2001-2015 Peter Selinger.
- This file is part of Potrace. It is free software and it is covered
- by the GNU General Public License. See the file COPYING for details. */
-
-
-/* Routines for manipulating greymaps, including reading pgm files. We
- only deal with greymaps of depth 8 bits. */
-
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <errno.h>
-
-#include "greymap.h"
-#include "bitops.h"
-
-#define INTBITS (8*sizeof(int))
-
-#define mod(a,n) ((a)>=(n) ? (a)%(n) : (a)>=0 ? (a) : (n)-1-(-1-(a))%(n))
-
-static int gm_readbody_pnm(FILE *f, greymap_t **gmp, int magic);
-static int gm_readbody_bmp(FILE *f, greymap_t **gmp);
-
-/* ---------------------------------------------------------------------- */
-/* basic greymap routines */
-
-/* return new un-initialized greymap. NULL with errno on error.
- Assumes w, h >= 0. */
-greymap_t *gm_new(int w, int h) {
- greymap_t *gm;
- ssize_t size = (ssize_t)w * (ssize_t)h * (ssize_t)sizeof(signed short int);
-
- /* check for overflow error */
- if (size < 0 || size / w / h != sizeof(signed short int)) {
- errno = ENOMEM;
- return NULL;
- }
-
- gm = (greymap_t *) malloc(sizeof(greymap_t));
- if (!gm) {
- return NULL;
- }
- gm->w = w;
- gm->h = h;
- gm->map = (signed short int *) malloc(size);
- if (!gm->map) {
- free(gm);
- return NULL;
- }
- return gm;
-}
-
-/* free the given greymap */
-void gm_free(greymap_t *gm) {
- if (gm) {
- free(gm->map);
- }
- free(gm);
-}
-
-/* duplicate the given greymap. Return NULL on error with errno set. */
-greymap_t *gm_dup(greymap_t *gm) {
- greymap_t *gm1 = gm_new(gm->w, gm->h);
- if (!gm1) {
- return NULL;
- }
- memcpy(gm1->map, gm->map, gm->w*gm->h*sizeof(signed short int));
- return gm1;
-}
-
-/* clear the given greymap to color b. */
-void gm_clear(greymap_t *gm, int b) {
- if (b==0) {
- memset(gm->map, 0, gm->w*gm->h*sizeof(signed short int));
- } else {
- for (int i=0; i<gm->w*gm->h; i++) {
- gm->map[i] = b;
- }
- }
-}
-
-/* ---------------------------------------------------------------------- */
-/* routines for reading pnm streams */
-
-/* read next character after whitespace and comments. Return EOF on
- end of file or error. */
-static int fgetc_ws(FILE *f) {
- int c;
-
- while (1) {
- c = fgetc(f);
- if (c=='#') {
- while (1) {
- c = fgetc(f);
- if (c=='\n' || c==EOF) {
- break;
- }
- }
- }
- /* space, tab, line feed, carriage return, form-feed */
- if (c!=' ' && c!='\t' && c!='\r' && c!='\n' && c!=12) {
- return c;
- }
- }
-}
-
-/* skip whitespace and comments, then read a non-negative decimal
- number from a stream. Return -1 on EOF. Tolerate other errors (skip
- bad characters). Do not the read any characters following the
- number (put next character back into the stream) */
-
-static int readnum(FILE *f) {
- int c;
- int acc;
-
- /* skip whitespace and comments */
- while (1) {
- c = fgetc_ws(f);
- if (c==EOF) {
- return -1;
- }
- if (c>='0' && c<='9') {
- break;
- }
- }
-
- /* first digit is already in c */
- acc = c-'0';
- while (1) {
- c = fgetc(f);
- if (c==EOF) {
- break;
- }
- if (c<'0' || c>'9') {
- ungetc(c, f);
- break;
- }
- acc *= 10;
- acc += c-'0';
- }
- return acc;
-}
-
-/* similar to readnum, but read only a single 0 or 1, and do not read
- any characters after it. */
-
-static int readbit(FILE *f) {
- int c;
-
- /* skip whitespace and comments */
- while (1) {
- c = fgetc_ws(f);
- if (c==EOF) {
- return -1;
- }
- if (c>='0' && c<='1') {
- break;
- }
- }
-
- return c-'0';
-}
-
-/* ---------------------------------------------------------------------- */
-
-/* read a PNM stream: P1-P6 format (see pnm(5)), or a BMP stream, and
- convert the output to a greymap. Return greymap in *gmp. Return 0
- on success, -1 on error with errno set, -2 on bad file format (with
- error message in gm_read_error), and 1 on premature end of file, -3
- on empty file (including files with only whitespace and comments),
- -4 if wrong magic number. If the return value is >=0, *gmp is
- valid. */
-
-char const *gm_read_error = NULL;
-
-int gm_read(FILE *f, greymap_t **gmp) {
- int magic[2];
-
- /* read magic number. We ignore whitespace and comments before the
- magic, for the benefit of concatenated files in P1-P3 format.
- Multiple P1-P3 images in a single file are not formally allowed
- by the PNM standard, but there is no harm in being lenient. */
-
- magic[0] = fgetc_ws(f);
- if (magic[0] == EOF) {
- /* files which contain only comments and whitespace count as "empty" */
- return -3;
- }
- magic[1] = fgetc(f);
- if (magic[0] == 'P' && magic[1] >= '1' && magic[1] <= '6') {
- return gm_readbody_pnm(f, gmp, magic[1]);
- }
- if (magic[0] == 'B' && magic[1] == 'M') {
- return gm_readbody_bmp(f, gmp);
- }
- return -4;
-}
-
-/* ---------------------------------------------------------------------- */
-/* read PNM format */
-
-/* read PNM stream after magic number. Return values as for gm_read */
-static int gm_readbody_pnm(FILE *f, greymap_t **gmp, int magic) {
- greymap_t *gm;
- int x, y, i, j, b, b1, sum;
- int bpr; /* bytes per row (as opposed to 4*gm->c) */
- int w, h, max;
-
- gm = NULL;
-
- w = readnum(f);
- if (w<0) {
- goto format_error;
- }
-
- h = readnum(f);
- if (h<0) {
- goto format_error;
- }
-
- /* allocate greymap */
- gm = gm_new(w, h);
- if (!gm) {
- return -1;
- }
-
- /* zero it out */
- gm_clear(gm, 0);
-
- switch (magic) {
- default:
- /* not reached */
- goto format_error;
-
- case '1':
- /* read P1 format: PBM ascii */
-
- for (y=h-1; y>=0; y--) {
- for (x=0; x<w; x++) {
- b = readbit(f);
- if (b<0) {
- goto eof;
- }
- GM_UPUT(gm, x, y, b ? 0 : 255);
- }
- }
- break;
-
- case '2':
- /* read P2 format: PGM ascii */
-
- max = readnum(f);
- if (max<1) {
- goto format_error;
- }
-
- for (y=h-1; y>=0; y--) {
- for (x=0; x<w; x++) {
- b = readnum(f);
- if (b<0) {
- goto eof;
- }
- GM_UPUT(gm, x, y, b*255/max);
- }
- }
- break;
-
- case '3':
- /* read P3 format: PPM ascii */
-
- max = readnum(f);
- if (max<1) {
- goto format_error;
- }
-
- for (y=h-1; y>=0; y--) {
- for (x=0; x<w; x++) {
- sum = 0;
- for (i=0; i<3; i++) {
- b = readnum(f);
- if (b<0) {
- goto eof;
- }
- sum += b;
- }
- GM_UPUT(gm, x, y, sum*(255/3)/max);
- }
- }
- break;
-
- case '4':
- /* read P4 format: PBM raw */
-
- b = fgetc(f); /* read single white-space character after height */
- if (b==EOF) {
- goto format_error;
- }
-
- bpr = (w+7)/8;
-
- for (y=h-1; y>=0; y--) {
- for (i=0; i<bpr; i++) {
- b = fgetc(f);
- if (b==EOF) {
- goto eof;
- }
- for (j=0; j<8; j++) {
- GM_PUT(gm, i*8+j, y, b & (0x80 >> j) ? 0 : 255);
- }
- }
- }
- break;
-
- case '5':
- /* read P5 format: PGM raw */
-
- max = readnum(f);
- if (max<1) {
- goto format_error;
- }
-
- b = fgetc(f); /* read single white-space character after max */
- if (b==EOF) {
- goto format_error;
- }
-
- for (y=h-1; y>=0; y--) {
- for (x=0; x<w; x++) {
- b = fgetc(f);
- if (b==EOF)
- goto eof;
- if (max>=256) {
- b <<= 8;
- b1 = fgetc(f);
- if (b1==EOF)
- goto eof;
- b |= b1;
- }
- GM_UPUT(gm, x, y, b*255/max);
- }
- }
- break;
-
- case '6':
- /* read P6 format: PPM raw */
-
- max = readnum(f);
- if (max<1) {
- goto format_error;
- }
-
- b = fgetc(f); /* read single white-space character after max */
- if (b==EOF) {
- goto format_error;
- }
-
- for (y=h-1; y>=0; y--) {
- for (x=0; x<w; x++) {
- sum = 0;
- for (i=0; i<3; i++) {
- b = fgetc(f);
- if (b==EOF) {
- goto eof;
- }
- if (max>=256) {
- b <<= 8;
- b1 = fgetc(f);
- if (b1==EOF)
- goto eof;
- b |= b1;
- }
- sum += b;
- }
- GM_UPUT(gm, x, y, sum*(255/3)/max);
- }
- }
- break;
- }
-
- *gmp = gm;
- return 0;
-
- eof:
- *gmp = gm;
- return 1;
-
- format_error:
- gm_free(gm);
- if (magic == '1' || magic == '4') {
- gm_read_error = "invalid pbm file";
- } else if (magic == '2' || magic == '5') {
- gm_read_error = "invalid pgm file";
- } else {
- gm_read_error = "invalid ppm file";
- }
- return -2;
-}
-
-/* ---------------------------------------------------------------------- */
-/* read BMP format */
-
-struct bmp_info_s {
- unsigned int FileSize;
- unsigned int reserved;
- unsigned int DataOffset;
- unsigned int InfoSize;
- unsigned int w; /* width */
- unsigned int h; /* height */
- unsigned int Planes;
- unsigned int bits; /* bits per sample */
- unsigned int comp; /* compression mode */
- unsigned int ImageSize;
- unsigned int XpixelsPerM;
- unsigned int YpixelsPerM;
- unsigned int ncolors; /* number of colors in palette */
- unsigned int ColorsImportant;
- unsigned int RedMask;
- unsigned int GreenMask;
- unsigned int BlueMask;
- unsigned int AlphaMask;
- unsigned int ctbits; /* sample size for color table */
- int topdown; /* top-down mode? */
-};
-typedef struct bmp_info_s bmp_info_t;
-
-/* auxiliary */
-
-static int bmp_count = 0; /* counter for byte padding */
-static int bmp_pos = 0; /* counter from start of BMP data */
-
-/* read n-byte little-endian integer. Return 1 on EOF or error, else
- 0. Assume n<=4. */
-static int bmp_readint(FILE *f, int n, unsigned int *p) {
- int i;
- unsigned int sum = 0;
- int b;
-
- for (i=0; i<n; i++) {
- b = fgetc(f);
- if (b==EOF) {
- return 1;
- }
- sum += b << (8*i);
- }
- bmp_count += n;
- bmp_pos += n;
- *p = sum;
- return 0;
-}
-
-/* reset padding boundary */
-static void bmp_pad_reset(void) {
- bmp_count = 0;
-}
-
-/* read padding bytes to 4-byte boundary. Return 1 on EOF or error,
- else 0. */
-static int bmp_pad(FILE *f) {
- int c, i, b;
-
- c = (-bmp_count) & 3;
- for (i=0; i<c; i++) {
- b = fgetc(f);
- if (b==EOF) {
- return 1;
- }
- }
- bmp_pos += c;
- bmp_count = 0;
- return 0;
-}
-
-/* forward to the new file position. Return 1 on EOF or error, else 0 */
-static int bmp_forward(FILE *f, int pos) {
- int b;
-
- while (bmp_pos < pos) {
- b = fgetc(f);
- if (b==EOF) {
- return 1;
- }
- bmp_pos++;
- bmp_count++;
- }
- return 0;
-}
-
-#define TRY(x) if (x) goto try_error
-#define TRY_EOF(x) if (x) goto eof
-
-/* correct y-coordinate for top-down format */
-#define ycorr(y) (bmpinfo.topdown ? bmpinfo.h-1-y : y)
-
-/* read BMP stream after magic number. Return values as for gm_read.
- We choose to be as permissive as possible, since there are many
- programs out there which produce BMP. For instance, ppmtobmp can
- produce codings with anywhere from 1-8 or 24 bits per sample,
- although most specifications only allow 1,4,8,24,32. We can also
- read both the old and new OS/2 BMP formats in addition to the
- Windows BMP format. */
-static int gm_readbody_bmp(FILE *f, greymap_t **gmp) {
- bmp_info_t bmpinfo;
- int *coltable;
- unsigned int b, c;
- unsigned int i, j;
- greymap_t *gm;
- unsigned int x, y;
- int col[2];
- unsigned int bitbuf;
- unsigned int n;
- unsigned int redshift, greenshift, blueshift;
-
- gm_read_error = NULL;
- gm = NULL;
- coltable = NULL;
-
- bmp_pos = 2; /* set file position */
-
- /* file header (minus magic number) */
- TRY(bmp_readint(f, 4, &bmpinfo.FileSize));
- TRY(bmp_readint(f, 4, &bmpinfo.reserved));
- TRY(bmp_readint(f, 4, &bmpinfo.DataOffset));
-
- /* info header */
- TRY(bmp_readint(f, 4, &bmpinfo.InfoSize));
- if (bmpinfo.InfoSize == 40 || bmpinfo.InfoSize == 64
- || bmpinfo.InfoSize == 108 || bmpinfo.InfoSize == 124) {
- /* Windows or new OS/2 format */
- bmpinfo.ctbits = 32; /* sample size in color table */
- TRY(bmp_readint(f, 4, &bmpinfo.w));
- TRY(bmp_readint(f, 4, &bmpinfo.h));
- TRY(bmp_readint(f, 2, &bmpinfo.Planes));
- TRY(bmp_readint(f, 2, &bmpinfo.bits));
- TRY(bmp_readint(f, 4, &bmpinfo.comp));
- TRY(bmp_readint(f, 4, &bmpinfo.ImageSize));
- TRY(bmp_readint(f, 4, &bmpinfo.XpixelsPerM));
- TRY(bmp_readint(f, 4, &bmpinfo.YpixelsPerM));
- TRY(bmp_readint(f, 4, &bmpinfo.ncolors));
- TRY(bmp_readint(f, 4, &bmpinfo.ColorsImportant));
- if (bmpinfo.InfoSize >= 108) { /* V4 and V5 bitmaps */
- TRY(bmp_readint(f, 4, &bmpinfo.RedMask));
- TRY(bmp_readint(f, 4, &bmpinfo.GreenMask));
- TRY(bmp_readint(f, 4, &bmpinfo.BlueMask));
- TRY(bmp_readint(f, 4, &bmpinfo.AlphaMask));
- }
- if (bmpinfo.w > 0x7fffffff) {
- goto format_error;
- }
- if (bmpinfo.h > 0x7fffffff) {
- bmpinfo.h = (-bmpinfo.h) & 0xffffffff;
- bmpinfo.topdown = 1;
- } else {
- bmpinfo.topdown = 0;
- }
- if (bmpinfo.h > 0x7fffffff) {
- goto format_error;
- }
- } else if (bmpinfo.InfoSize == 12) {
- /* old OS/2 format */
- bmpinfo.ctbits = 24; /* sample size in color table */
- TRY(bmp_readint(f, 2, &bmpinfo.w));
- TRY(bmp_readint(f, 2, &bmpinfo.h));
- TRY(bmp_readint(f, 2, &bmpinfo.Planes));
- TRY(bmp_readint(f, 2, &bmpinfo.bits));
- bmpinfo.comp = 0;
- bmpinfo.ncolors = 0;
- bmpinfo.topdown = 0;
- } else {
- goto format_error;
- }
-
- if (bmpinfo.comp == 3 && bmpinfo.InfoSize < 108) {
- /* bitfield feature is only understood with V4 and V5 format */
- goto format_error;
- }
-
- /* forward to color table (e.g., if bmpinfo.InfoSize == 64) */
- TRY(bmp_forward(f, 14+bmpinfo.InfoSize));
-
- if (bmpinfo.Planes != 1) {
- gm_read_error = "cannot handle bmp planes";
- goto format_error; /* can't handle planes */
- }
-
- if (bmpinfo.ncolors == 0) {
- bmpinfo.ncolors = 1 << bmpinfo.bits;
- }
-
- /* color table, present only if bmpinfo.bits <= 8. */
- if (bmpinfo.bits <= 8) {
- coltable = (int *) calloc(bmpinfo.ncolors, sizeof(int));
- if (!coltable) {
- goto std_error;
- }
- /* NOTE: since we are reading a greymap, we can immediately convert
- the color table entries to grey values. */
- for (i=0; i<bmpinfo.ncolors; i++) {
- TRY(bmp_readint(f, bmpinfo.ctbits/8, &c));
- c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
- coltable[i] = c/3;
- }
- }
-
- /* forward to data */
- if (bmpinfo.InfoSize != 12) { /* not old OS/2 format */
- TRY(bmp_forward(f, bmpinfo.DataOffset));
- }
-
- /* allocate greymap */
- gm = gm_new(bmpinfo.w, bmpinfo.h);
- if (!gm) {
- goto std_error;
- }
-
- /* zero it out */
- gm_clear(gm, 0);
-
- switch (bmpinfo.bits + 0x100*bmpinfo.comp) {
-
- default:
- goto format_error;
- break;
-
- case 0x001: /* monochrome palette */
-
- /* raster data */
- for (y=0; y<bmpinfo.h; y++) {
- bmp_pad_reset();
- for (i=0; 8*i<bmpinfo.w; i++) {
- TRY_EOF(bmp_readint(f, 1, &b));
- for (j=0; j<8; j++) {
- GM_PUT(gm, i*8+j, ycorr(y), b & (0x80 >> j) ? coltable[1] : coltable[0]);
- }
- }
- TRY(bmp_pad(f));
- }
- break;
-
- case 0x002: /* 2-bit to 8-bit palettes */
- case 0x003:
- case 0x004:
- case 0x005:
- case 0x006:
- case 0x007:
- case 0x008:
- for (y=0; y<bmpinfo.h; y++) {
- bmp_pad_reset();
- bitbuf = 0; /* bit buffer: bits in buffer are high-aligned */
- n = 0; /* number of bits currently in bitbuffer */
- for (x=0; x<bmpinfo.w; x++) {
- if (n < bmpinfo.bits) {
- TRY_EOF(bmp_readint(f, 1, &b));
- bitbuf |= b << (INTBITS - 8 - n);
- n += 8;
- }
- b = bitbuf >> (INTBITS - bmpinfo.bits);
- bitbuf <<= bmpinfo.bits;
- n -= bmpinfo.bits;
- GM_UPUT(gm, x, ycorr(y), coltable[b]);
- }
- TRY(bmp_pad(f));
- }
- break;
-
- case 0x010: /* 16-bit encoding */
- /* can't do this format because it is not well-documented and I
- don't have any samples */
- gm_read_error = "cannot handle bmp 16-bit coding";
- goto format_error;
- break;
-
- case 0x018: /* 24-bit encoding */
- case 0x020: /* 32-bit encoding */
- for (y=0; y<bmpinfo.h; y++) {
- bmp_pad_reset();
- for (x=0; x<bmpinfo.w; x++) {
- TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
- c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
- GM_UPUT(gm, x, ycorr(y), c/3);
- }
- TRY(bmp_pad(f));
- }
- break;
-
- case 0x320: /* 32-bit encoding with bitfields */
- redshift = lobit(bmpinfo.RedMask);
- greenshift = lobit(bmpinfo.GreenMask);
- blueshift = lobit(bmpinfo.BlueMask);
-
- for (y=0; y<bmpinfo.h; y++) {
- bmp_pad_reset();
- for (x=0; x<bmpinfo.w; x++) {
- TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
- c = ((c & bmpinfo.RedMask) >> redshift) + ((c & bmpinfo.GreenMask) >> greenshift) + ((c & bmpinfo.BlueMask) >> blueshift);
- GM_UPUT(gm, x, ycorr(y), c/3);
- }
- TRY(bmp_pad(f));
- }
- break;
-
- case 0x204: /* 4-bit runlength compressed encoding (RLE4) */
- x = 0;
- y = 0;
- while (1) {
- TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
- TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
- if (b>0) {
- /* repeat count */
- col[0] = coltable[(c>>4) & 0xf];
- col[1] = coltable[c & 0xf];
- for (i=0; i<b && x<bmpinfo.w; i++) {
- if (x>=bmpinfo.w) {
- x=0;
- y++;
- }
- if (y>=bmpinfo.h) {
- break;
- }
- GM_UPUT(gm, x, ycorr(y), col[i&1]);
- x++;
- }
- } else if (c == 0) {
- /* end of line */
- y++;
- x = 0;
- } else if (c == 1) {
- /* end of greymap */
- break;
- } else if (c == 2) {
- /* "delta": skip pixels in x and y directions */
- TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
- TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
- x += b;
- y += c;
- } else {
- /* verbatim segment */
- for (i=0; i<c; i++) {
- if ((i&1)==0) {
- TRY_EOF(bmp_readint(f, 1, &b));
- }
- if (x>=bmpinfo.w) {
- x=0;
- y++;
- }
- if (y>=bmpinfo.h) {
- break;
- }
- GM_PUT(gm, x, ycorr(y), coltable[(b>>(4-4*(i&1))) & 0xf]);
- x++;
- }
- if ((c+1) & 2) {
- /* pad to 16-bit boundary */
- TRY_EOF(bmp_readint(f, 1, &b));
- }
- }
- }
- break;
-
- case 0x108: /* 8-bit runlength compressed encoding (RLE8) */
- x = 0;
- y = 0;
- while (1) {
- TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
- TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
- if (b>0) {
- /* repeat count */
- for (i=0; i<b; i++) {
- if (x>=bmpinfo.w) {
- x=0;
- y++;
- }
- if (y>=bmpinfo.h) {
- break;
- }
- GM_UPUT(gm, x, ycorr(y), coltable[c]);
- x++;
- }
- } else if (c == 0) {
- /* end of line */
- y++;
- x = 0;
- } else if (c == 1) {
- /* end of greymap */
- break;
- } else if (c == 2) {
- /* "delta": skip pixels in x and y directions */
- TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
- TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
- x += b;
- y += c;
- } else {
- /* verbatim segment */
- for (i=0; i<c; i++) {
- TRY_EOF(bmp_readint(f, 1, &b));
- if (x>=bmpinfo.w) {
- x=0;
- y++;
- }
- if (y>=bmpinfo.h) {
- break;
- }
- GM_PUT(gm, x, ycorr(y), coltable[b]);
- x++;
- }
- if (c & 1) {
- /* pad input to 16-bit boundary */
- TRY_EOF(bmp_readint(f, 1, &b));
- }
- }
- }
- break;
-
- } /* switch */
-
- /* skip any potential junk after the data section, but don't
- complain in case EOF is encountered */
- bmp_forward(f, bmpinfo.FileSize);
-
- free(coltable);
- *gmp = gm;
- return 0;
-
- eof:
- free(coltable);
- *gmp = gm;
- return 1;
-
- format_error:
- try_error:
- free(coltable);
- free(gm);
- if (!gm_read_error) {
- gm_read_error = "invalid bmp file";
- }
- return -2;
-
- std_error:
- free(coltable);
- free(gm);
- return -1;
-}
-
-/* ---------------------------------------------------------------------- */
-
-/* write a pgm stream, either P2 or (if raw != 0) P5 format. Include
- one-line comment if non-NULL. Mode determines how out-of-range
- color values are converted. Gamma is the desired gamma correction,
- if any (set to 2.2 if the image is to look optimal on a CRT monitor,
- 2.8 for LCD). Set to 1.0 for no gamma correction */
-
-int gm_writepgm(FILE *f, greymap_t *gm, char *comment, int raw, int mode, double gamma) {
- int x, y, v;
- int gammatable[256];
-
- /* prepare gamma correction lookup table */
- if (gamma != 1.0) {
- gammatable[0] = 0;
- for (v=1; v<256; v++) {
- gammatable[v] = (int)(255 * exp(log(v/255.0)/gamma) + 0.5);
- }
- } else {
- for (v=0; v<256; v++) {
- gammatable[v] = v;
- }
- }
-
- fprintf(f, raw ? "P5\n" : "P2\n");
- if (comment && *comment) {
- fprintf(f, "# %s\n", comment);
- }
- fprintf(f, "%d %d 255\n", gm->w, gm->h);
- for (y=gm->h-1; y>=0; y--) {
- for (x=0; x<gm->w; x++) {
- v = GM_UGET(gm, x, y);
- if (mode == GM_MODE_NONZERO) {
- if (v > 255) {
- v = 510 - v;
- }
- if (v < 0) {
- v = 0;
- }
- } else if (mode == GM_MODE_ODD) {
- v = mod(v, 510);
- if (v > 255) {
- v = 510 - v;
- }
- } else if (mode == GM_MODE_POSITIVE) {
- if (v < 0) {
- v = 0;
- } else if (v > 255) {
- v = 255;
- }
- } else if (mode == GM_MODE_NEGATIVE) {
- v = 510 - v;
- if (v < 0) {
- v = 0;
- } else if (v > 255) {
- v = 255;
- }
- }
- v = gammatable[v];
-
- if (raw) {
- fputc(v, f);
- } else {
- fprintf(f, x == gm->w-1 ? "%d\n" : "%d ", v);
- }
- }
- }
- return 0;
-}
-
-/* ---------------------------------------------------------------------- */
-/* output - for primitive debugging purposes only! */
-
-/* print greymap to screen */
-int gm_print(FILE *f, greymap_t *gm) {
- int x, y;
- int xx, yy;
- int d, t;
- int sw, sh;
-
- sw = gm->w < 79 ? gm->w : 79;
- sh = gm->w < 79 ? gm->h : gm->h*sw*44/(79*gm->w);
-
- for (yy=sh-1; yy>=0; yy--) {
- for (xx=0; xx<sw; xx++) {
- d=0;
- t=0;
- for (x=xx*gm->w/sw; x<(xx+1)*gm->w/sw; x++) {
- for (y=yy*gm->h/sh; y<(yy+1)*gm->h/sh; y++) {
- d += GM_GET(gm, x, y);
- t += 256;
- }
- }
- fputc("*#=- "[5*d/t], f); /* what a cute trick :) */
- }
- fputc('\n', f);
- }
- return 0;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2026-05-19 10:49:54 +0000