--- /dev/null
+/* GIF reading routines based on those in pbmplus:ppm/giftoppm.c, bearing
+ * following copyright notice:
+ */
+
+/* +-------------------------------------------------------------------+ */
+/* | Copyright 1990, David Koblas. | */
+/* | Permission to use, copy, modify, and distribute this software | */
+/* | and its documentation for any purpose and without fee is hereby | */
+/* | granted, provided that the above copyright notice appear in all | */
+/* | copies and that both that copyright notice and this permission | */
+/* | notice appear in supporting documentation. This software is | */
+/* | provided "as is" without express or implied warranty. | */
+/* +-------------------------------------------------------------------+ */
+
+
+#include "config.h"
+#include "tile.h"
+
+#ifndef MONITOR_HEAP
+extern long *FDECL(alloc, (unsigned int));
+#endif
+
+#define PPM_ASSIGN(p,red,grn,blu) do { (p).r = (red); (p).g = (grn); (p).b = (blu); } while ( 0 )
+
+#define MAX_LWZ_BITS 12
+
+#define INTERLACE 0x40
+#define LOCALCOLORMAP 0x80
+#define BitSet(byte, bit) (((byte) & (bit)) == (bit))
+
+#define ReadOK(file,buffer,len) (fread((genericptr_t)buffer, (int)len, 1, file) != 0)
+
+#define LM_to_uint(a,b) (((b)<<8)|(a))
+
+struct gifscreen {
+ int Width;
+ int Height;
+ int Colors;
+ int ColorResolution;
+ int Background;
+ int AspectRatio;
+ int Interlace;
+} GifScreen;
+
+struct {
+ int transparent;
+ int delayTime;
+ int inputFlag;
+ int disposal;
+} Gif89 = { -1, -1, -1, 0 };
+
+int ZeroDataBlock = FALSE;
+
+static FILE *gif_file;
+static int tiles_across, tiles_down, curr_tiles_across, curr_tiles_down;
+static pixel **image;
+static unsigned char input_code_size;
+
+static int FDECL(GetDataBlock, (FILE *fd, unsigned char *buf));
+static void FDECL(DoExtension, (FILE *fd, int label));
+static boolean FDECL(ReadColorMap, (FILE *fd, int number));
+static void FDECL(read_header, (FILE *fd));
+static int FDECL(GetCode, (FILE *fd, int code_size, int flag));
+static int FDECL(LWZReadByte, (FILE *fd, int flag, int input_code_size));
+static void FDECL(ReadInterleavedImage, (FILE *fd, int len, int height));
+static void FDECL(ReadTileStrip, (FILE *fd, int len));
+
+/* These should be in gif.h, but there isn't one. */
+boolean FDECL(fopen_gif_file, (const char *, const char *));
+boolean FDECL(read_gif_tile, (pixel(*)[]));
+int NDECL(fclose_gif_file);
+
+static int
+GetDataBlock(fd, buf)
+FILE *fd;
+unsigned char *buf;
+{
+ unsigned char count;
+
+ if (!ReadOK(fd,&count,1)) {
+ Fprintf(stderr, "error in getting DataBlock size\n");
+ return -1;
+ }
+
+ ZeroDataBlock = (count == 0);
+
+ if ((count != 0) && (!ReadOK(fd, buf, count))) {
+ Fprintf(stderr, "error in reading DataBlock\n");
+ return -1;
+ }
+
+ return count;
+}
+
+static void
+DoExtension(fd, label)
+FILE *fd;
+int label;
+{
+ static char buf[256];
+ char *str;
+
+ switch (label) {
+ case 0x01: /* Plain Text Extension */
+ str = "Plain Text Extension";
+#ifdef notdef
+ if (GetDataBlock(fd, (unsigned char*) buf) == 0)
+ ;
+
+ lpos = LM_to_uint(buf[0], buf[1]);
+ tpos = LM_to_uint(buf[2], buf[3]);
+ width = LM_to_uint(buf[4], buf[5]);
+ height = LM_to_uint(buf[6], buf[7]);
+ cellw = buf[8];
+ cellh = buf[9];
+ foreground = buf[10];
+ background = buf[11];
+
+ while (GetDataBlock(fd, (unsigned char*) buf) != 0) {
+ PPM_ASSIGN(image[ypos][xpos],
+ cmap[CM_RED][v],
+ cmap[CM_GREEN][v],
+ cmap[CM_BLUE][v]);
+ ++index;
+ }
+
+ return;
+#else
+ break;
+#endif
+ case 0xff: /* Application Extension */
+ str = "Application Extension";
+ break;
+ case 0xfe: /* Comment Extension */
+ str = "Comment Extension";
+ while (GetDataBlock(fd, (unsigned char*) buf) != 0) {
+ Fprintf(stderr, "gif comment: %s\n", buf );
+ }
+ return;
+ case 0xf9: /* Graphic Control Extension */
+ str = "Graphic Control Extension";
+ (void) GetDataBlock(fd, (unsigned char*) buf);
+ Gif89.disposal = (buf[0] >> 2) & 0x7;
+ Gif89.inputFlag = (buf[0] >> 1) & 0x1;
+ Gif89.delayTime = LM_to_uint(buf[1],buf[2]);
+ if ((buf[0] & 0x1) != 0)
+ Gif89.transparent = buf[3];
+
+ while (GetDataBlock(fd, (unsigned char*) buf) != 0)
+ ;
+ return;
+ default:
+ str = buf;
+ Sprintf(buf, "UNKNOWN (0x%02x)", label);
+ break;
+ }
+
+ Fprintf(stderr, "got a '%s' extension\n", str);
+
+ while (GetDataBlock(fd, (unsigned char*) buf) != 0)
+ ;
+}
+
+static
+boolean
+ReadColorMap(fd,number)
+FILE *fd;
+int number;
+{
+ int i;
+ unsigned char rgb[3];
+
+ for (i = 0; i < number; ++i) {
+ if (!ReadOK(fd, rgb, sizeof(rgb))) {
+ return(FALSE);
+ }
+
+ ColorMap[CM_RED][i] = rgb[0] ;
+ ColorMap[CM_GREEN][i] = rgb[1] ;
+ ColorMap[CM_BLUE][i] = rgb[2] ;
+ }
+ colorsinmap = number;
+ return TRUE;
+}
+
+/*
+ * Read gif header, including colormaps. We expect only one image per
+ * file, so if that image has a local colormap, overwrite the global one.
+ */
+static void
+read_header(fd)
+FILE *fd;
+{
+ unsigned char buf[16];
+ unsigned char c;
+ char version[4];
+
+ if (!ReadOK(fd,buf,6)) {
+ Fprintf(stderr, "error reading magic number\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (strncmp((genericptr_t)buf,"GIF",3) != 0) {
+ Fprintf(stderr, "not a GIF file\n");
+ exit(EXIT_FAILURE);
+ }
+
+ (void) strncpy(version, (char *)buf + 3, 3);
+ version[3] = '\0';
+
+ if ((strcmp(version, "87a") != 0) && (strcmp(version, "89a") != 0)) {
+ Fprintf(stderr, "bad version number, not '87a' or '89a'\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (!ReadOK(fd,buf,7)) {
+ Fprintf(stderr, "failed to read screen descriptor\n");
+ exit(EXIT_FAILURE);
+ }
+
+ GifScreen.Width = LM_to_uint(buf[0],buf[1]);
+ GifScreen.Height = LM_to_uint(buf[2],buf[3]);
+ GifScreen.Colors = 2<<(buf[4]&0x07);
+ GifScreen.ColorResolution = (((buf[4]&0x70)>>3)+1);
+ GifScreen.Background = buf[5];
+ GifScreen.AspectRatio = buf[6];
+
+ if (BitSet(buf[4], LOCALCOLORMAP)) { /* Global Colormap */
+ if (!ReadColorMap(fd, GifScreen.Colors)) {
+ Fprintf(stderr, "error reading global colormap\n");
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ if (GifScreen.AspectRatio != 0 && GifScreen.AspectRatio != 49) {
+ Fprintf(stderr, "warning - non-square pixels\n");
+ }
+
+ for (;;) {
+ if (!ReadOK(fd,&c,1)) {
+ Fprintf(stderr, "EOF / read error on image data\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (c == ';') { /* GIF terminator */
+ return;
+ }
+
+ if (c == '!') { /* Extension */
+ if (!ReadOK(fd,&c,1)) {
+ Fprintf(stderr,
+ "EOF / read error on extension function code\n");
+ exit(EXIT_FAILURE);
+ }
+ DoExtension(fd, (int)c);
+ continue;
+ }
+
+ if (c != ',') { /* Not a valid start character */
+ Fprintf(stderr,
+ "bogus character 0x%02x, ignoring\n", (int) c);
+ continue;
+ }
+
+ if (!ReadOK(fd,buf,9)) {
+ Fprintf(stderr, "couldn't read left/top/width/height\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (BitSet(buf[8], LOCALCOLORMAP)) {
+ /* replace global color map with local */
+ GifScreen.Colors = 1<<((buf[8]&0x07)+1);
+ if (!ReadColorMap(fd, GifScreen.Colors)) {
+ Fprintf(stderr, "error reading local colormap\n");
+ exit(EXIT_FAILURE);
+ }
+
+ }
+ if (GifScreen.Width != LM_to_uint(buf[4],buf[5])) {
+ Fprintf(stderr, "warning: widths don't match\n");
+ GifScreen.Width = LM_to_uint(buf[4],buf[5]);
+ }
+ if (GifScreen.Height != LM_to_uint(buf[6],buf[7])) {
+ Fprintf(stderr, "warning: heights don't match\n");
+ GifScreen.Height = LM_to_uint(buf[6],buf[7]);
+ }
+ GifScreen.Interlace = BitSet(buf[8], INTERLACE);
+ return;
+ }
+}
+
+static int
+GetCode(fd, code_size, flag)
+FILE *fd;
+int code_size;
+int flag;
+{
+ static unsigned char buf[280];
+ static int curbit, lastbit, done, last_byte;
+ int i, j, ret;
+ unsigned char count;
+
+ if (flag) {
+ curbit = 0;
+ lastbit = 0;
+ done = FALSE;
+ return 0;
+ }
+
+ if ((curbit+code_size) >= lastbit) {
+ if (done) {
+ if (curbit >= lastbit)
+ Fprintf(stderr, "ran off the end of my bits\n");
+ return -1;
+ }
+ buf[0] = buf[last_byte-2];
+ buf[1] = buf[last_byte-1];
+
+ if ((count = GetDataBlock(fd, &buf[2])) == 0)
+ done = TRUE;
+
+ last_byte = 2 + count;
+ curbit = (curbit - lastbit) + 16;
+ lastbit = (2+count)*8 ;
+ }
+
+ ret = 0;
+ for (i = curbit, j = 0; j < code_size; ++i, ++j)
+ ret |= ((buf[ i / 8 ] & (1 << (i % 8))) != 0) << j;
+
+ curbit += code_size;
+
+ return ret;
+}
+
+static int
+LWZReadByte(fd, flag, input_code_size)
+FILE *fd;
+int flag;
+int input_code_size;
+{
+ static int fresh = FALSE;
+ int code, incode;
+ static int code_size, set_code_size;
+ static int max_code, max_code_size;
+ static int firstcode, oldcode;
+ static int clear_code, end_code;
+ static int table[2][(1<< MAX_LWZ_BITS)];
+ static int stack[(1<<(MAX_LWZ_BITS))*2], *sp;
+ register int i;
+
+ if (flag) {
+ set_code_size = input_code_size;
+ code_size = set_code_size+1;
+ clear_code = 1 << set_code_size ;
+ end_code = clear_code + 1;
+ max_code_size = 2*clear_code;
+ max_code = clear_code+2;
+
+ (void) GetCode(fd, 0, TRUE);
+
+ fresh = TRUE;
+
+ for (i = 0; i < clear_code; ++i) {
+ table[0][i] = 0;
+ table[1][i] = i;
+ }
+ for (; i < (1<<MAX_LWZ_BITS); ++i)
+ table[0][i] = table[1][0] = 0;
+
+ sp = stack;
+
+ return 0;
+ } else if (fresh) {
+ fresh = FALSE;
+ do {
+ firstcode = oldcode = GetCode(fd, code_size, FALSE);
+ } while (firstcode == clear_code);
+ return firstcode;
+ }
+
+ if (sp > stack)
+ return *--sp;
+
+ while ((code = GetCode(fd, code_size, FALSE)) >= 0) {
+ if (code == clear_code) {
+ for (i = 0; i < clear_code; ++i) {
+ table[0][i] = 0;
+ table[1][i] = i;
+ }
+ for (; i < (1<<MAX_LWZ_BITS); ++i)
+ table[0][i] = table[1][i] = 0;
+ code_size = set_code_size+1;
+ max_code_size = 2*clear_code;
+ max_code = clear_code+2;
+ sp = stack;
+ firstcode = oldcode = GetCode(fd, code_size, FALSE);
+ return firstcode;
+ } else if (code == end_code) {
+ int count;
+ unsigned char buf[260];
+
+ if (ZeroDataBlock)
+ return -2;
+
+ while ((count = GetDataBlock(fd, buf)) > 0)
+ ;
+
+ if (count != 0)
+ Fprintf(stderr,
+ "missing EOD in data stream (common occurrence)\n");
+ return -2;
+ }
+
+ incode = code;
+
+ if (code >= max_code) {
+ *sp++ = firstcode;
+ code = oldcode;
+ }
+
+ while (code >= clear_code) {
+ *sp++ = table[1][code];
+ if (code == table[0][code]) {
+ Fprintf(stderr, "circular table entry BIG ERROR\n");
+ exit(EXIT_FAILURE);
+ }
+ code = table[0][code];
+ }
+
+ *sp++ = firstcode = table[1][code];
+
+ if ((code = max_code) <(1<<MAX_LWZ_BITS)) {
+ table[0][code] = oldcode;
+ table[1][code] = firstcode;
+ ++max_code;
+ if ((max_code >= max_code_size) &&
+ (max_code_size < (1<<MAX_LWZ_BITS))) {
+ max_code_size *= 2;
+ ++code_size;
+ }
+ }
+
+ oldcode = incode;
+
+ if (sp > stack)
+ return *--sp;
+ }
+ return code;
+}
+
+
+static void
+ReadInterleavedImage(fd, len, height)
+FILE *fd;
+int len, height;
+{
+ int v;
+ int xpos = 0, ypos = 0, pass = 0;
+
+ while ((v = LWZReadByte(fd,FALSE,(int)input_code_size)) >= 0 ) {
+ PPM_ASSIGN(image[ypos][xpos], ColorMap[CM_RED][v],
+ ColorMap[CM_GREEN][v], ColorMap[CM_BLUE][v]);
+
+ ++xpos;
+ if (xpos == len) {
+ xpos = 0;
+ switch (pass) {
+ case 0:
+ case 1:
+ ypos += 8; break;
+ case 2:
+ ypos += 4; break;
+ case 3:
+ ypos += 2; break;
+ }
+
+ if (ypos >= height) {
+ ++pass;
+ switch (pass) {
+ case 1:
+ ypos = 4; break;
+ case 2:
+ ypos = 2; break;
+ case 3:
+ ypos = 1; break;
+ default:
+ goto fini;
+ }
+ }
+ }
+ if (ypos >= height)
+ break;
+ }
+
+fini:
+ if (LWZReadByte(fd,FALSE,(int)input_code_size)>=0)
+ Fprintf(stderr, "too much input data, ignoring extra...\n");
+}
+
+static
+void
+ReadTileStrip(fd,len)
+FILE *fd;
+int len;
+{
+ int v;
+ int xpos = 0, ypos = 0;
+
+ while ((v = LWZReadByte(fd,FALSE,(int)input_code_size)) >= 0 ) {
+ PPM_ASSIGN(image[ypos][xpos], ColorMap[CM_RED][v],
+ ColorMap[CM_GREEN][v], ColorMap[CM_BLUE][v]);
+
+ ++xpos;
+ if (xpos == len) {
+ xpos = 0;
+ ++ypos;
+ }
+ if (ypos >= TILE_Y)
+ break;
+ }
+}
+
+
+
+
+boolean
+fopen_gif_file(filename, type)
+const char *filename;
+const char *type;
+{
+ int i;
+
+ if (strcmp(type, RDBMODE)) {
+ Fprintf(stderr, "using reading routine for non-reading?\n");
+ return FALSE;
+ }
+ gif_file = fopen(filename, type);
+ if (gif_file == (FILE *)0) {
+ Fprintf(stderr, "cannot open gif file %s\n", filename);
+ return FALSE;
+ }
+
+ read_header(gif_file);
+ if (GifScreen.Width % TILE_X) {
+ Fprintf(stderr, "error: width %d not divisible by %d\n",
+ GifScreen.Width, TILE_X);
+ exit(EXIT_FAILURE);
+ }
+ tiles_across = GifScreen.Width / TILE_X;
+ curr_tiles_across = 0;
+ if (GifScreen.Height % TILE_Y) {
+ Fprintf(stderr, "error: height %d not divisible by %d\n",
+ GifScreen.Height, TILE_Y);
+ /* exit(EXIT_FAILURE) */;
+ }
+ tiles_down = GifScreen.Height / TILE_Y;
+ curr_tiles_down = 0;
+
+ if (GifScreen.Interlace) {
+ /* sigh -- hope this doesn't happen on micros */
+ image = (pixel **)alloc(GifScreen.Height * sizeof(pixel *));
+ for (i = 0; i < GifScreen.Height; i++) {
+ image[i] = (pixel *) alloc(GifScreen.Width * sizeof(pixel));
+ }
+ } else {
+ image = (pixel **)alloc(TILE_Y * sizeof(pixel *));
+ for (i = 0; i < TILE_Y; i++) {
+ image[i] = (pixel *) alloc(GifScreen.Width * sizeof(pixel));
+ }
+ }
+
+ /*
+ ** Initialize the Compression routines
+ */
+ if (!ReadOK(gif_file,&input_code_size,1)) {
+ Fprintf(stderr, "EOF / read error on image data\n");
+ exit(EXIT_FAILURE);
+ }
+
+ if (LWZReadByte(gif_file, TRUE, (int)input_code_size) < 0) {
+ Fprintf(stderr, "error reading image\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* read first section */
+ if (GifScreen.Interlace) {
+ ReadInterleavedImage(gif_file,
+ GifScreen.Width,GifScreen.Height);
+ } else {
+ ReadTileStrip(gif_file,GifScreen.Width);
+ }
+ return TRUE;
+}
+
+/* Read a tile. Returns FALSE when there are no more tiles */
+boolean
+read_gif_tile(pixels)
+pixel (*pixels)[TILE_X];
+{
+ int i, j;
+
+ if (curr_tiles_down >= tiles_down) return FALSE;
+ if (curr_tiles_across == tiles_across) {
+ curr_tiles_across = 0;
+ curr_tiles_down++;
+ if (curr_tiles_down >= tiles_down) return FALSE;
+ if (!GifScreen.Interlace)
+ ReadTileStrip(gif_file,GifScreen.Width);
+ }
+ if (GifScreen.Interlace) {
+ for (j = 0; j < TILE_Y; j++) {
+ for (i = 0; i < TILE_X; i++) {
+ pixels[j][i] = image[curr_tiles_down*TILE_Y + j]
+ [curr_tiles_across*TILE_X + i];
+ }
+ }
+ } else {
+ for (j = 0; j < TILE_Y; j++) {
+ for (i = 0; i < TILE_X; i++) {
+ pixels[j][i] = image[j][curr_tiles_across*TILE_X + i];
+ }
+ }
+ }
+ curr_tiles_across++;
+
+ /* check for "filler" tile */
+ for (j = 0; j < TILE_Y; j++) {
+ for (i = 0; i < TILE_X && i < 4; i += 2) {
+ if (pixels[j][i].r != ColorMap[CM_RED][0] ||
+ pixels[j][i].g != ColorMap[CM_GREEN][0] ||
+ pixels[j][i].b != ColorMap[CM_BLUE][0] ||
+ pixels[j][i+1].r != ColorMap[CM_RED][1] ||
+ pixels[j][i+1].g != ColorMap[CM_GREEN][1] ||
+ pixels[j][i+1].b != ColorMap[CM_BLUE][1])
+ return TRUE;
+ }
+ }
+ return FALSE;
+}
+
+int
+fclose_gif_file()
+{
+ int i;
+
+ if (GifScreen.Interlace) {
+ for (i = 0; i < GifScreen.Height; i++) {
+ free((genericptr_t)image[i]);
+ }
+ free((genericptr_t)image);
+ } else {
+ for (i = 0; i < TILE_Y; i++) {
+ free((genericptr_t)image[i]);
+ }
+ free((genericptr_t)image);
+ }
+ return(fclose(gif_file));
+}
+
+#ifndef AMIGA
+static char *std_args[] = { "tilemap", /* dummy argv[0] */
+ "monsters.gif", "monsters.txt",
+ "objects.gif", "objects.txt",
+ "other.gif", "other.txt" };
+
+int
+main(argc, argv)
+int argc;
+char *argv[];
+{
+ pixel pixels[TILE_Y][TILE_X];
+
+ if (argc == 1) {
+ argc = SIZE(std_args);
+ argv = std_args;
+ } else if (argc != 3) {
+ Fprintf(stderr, "usage: gif2txt giffile txtfile\n");
+ exit(EXIT_FAILURE);
+ }
+
+ while (argc > 1) {
+ if (!fopen_gif_file(argv[1], RDBMODE))
+ exit(EXIT_FAILURE);
+
+ init_colormap();
+
+ if (!fopen_text_file(argv[2], WRTMODE)) {
+ (void) fclose_gif_file();
+ exit(EXIT_FAILURE);
+ }
+
+ while (read_gif_tile(pixels))
+ (void) write_text_tile(pixels);
+
+ (void) fclose_gif_file();
+ (void) fclose_text_file();
+
+ argc -= 2;
+ argv += 2;
+ }
+ exit(EXIT_SUCCESS);
+ /*NOTREACHED*/
+ return 0;
+}
+#endif
projects / nethack / commitdiff