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Diffstat (limited to 'Build/source/libs/potrace/potrace-1.11/src/greymap.c')
-rw-r--r--Build/source/libs/potrace/potrace-1.11/src/greymap.c929
1 files changed, 929 insertions, 0 deletions
diff --git a/Build/source/libs/potrace/potrace-1.11/src/greymap.c b/Build/source/libs/potrace/potrace-1.11/src/greymap.c
new file mode 100644
index 00000000000..ebbe21213af
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-1.11/src/greymap.c
@@ -0,0 +1,929 @@
+/* Copyright (C) 2001-2013 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 "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 */
+
+greymap_t *gm_new(int w, int h) {
+ greymap_t *gm;
+
+ gm = (greymap_t *) malloc(sizeof(greymap_t));
+ if (!gm) {
+ return NULL;
+ }
+ gm->w = w;
+ gm->h = h;
+ gm->map = (signed short int *) malloc(w*h*sizeof(signed short int));
+ 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) {
+ int i;
+
+ if (b==0) {
+ memset(gm->map, 0, gm->w*gm->h*sizeof(signed short int));
+ } else {
+ for (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 *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 ((signed int)bmpinfo.h < 0) {
+ bmpinfo.h = -bmpinfo.h;
+ bmpinfo.topdown = 1;
+ } else {
+ bmpinfo.topdown = 0;
+ }
+ } 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 *) malloc(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 2.39.1) at 2024-12-27 04:26:11 +0000