./ 755 3760 0 0 4446542150 4161 ./gif2sun.c 644 3760 1 23332 4446542147 6021 /* gif2sun.c -- convert GIF picture files to Sun rasterfile format runs on Sun 3/4 -- not 386 -- byteorder must be Motorola-style version 1.1 note: bug fixed in extension reading code. Timo Rossi 1989 -- converted from gif2iff.c converted from agif.c */ #include #include #include char *malloc(); typedef char BYTE; typedef unsigned char UBYTE; typedef short WORD; typedef unsigned short UWORD; typedef long LONG; typedef unsigned long ULONG; #define TRUE 1 #define FALSE 0 /* GIF stuff */ #define GIF_SIGNATURE "GIF87a" /* GIF file identifier */ #define IMAGE_SEPARATOR ',' #define EXTENSION_INTRODUCER '!' #define GIF_TERMINATOR ';' struct ScreenDescriptor { UWORD Width,Height; UBYTE PixelFlags; UBYTE Background; UBYTE NotUsed; }; struct ImageDescriptor { UWORD Left,Top; UWORD Width,Height; UBYTE PixelFlags; }; /* sizeof(struct ScreenDescriptor) or sizeof(struct Imagedescriptor) can't be used when reading from file because of structure alignment the following values are used */ #define SCR_DESCR_LENGTH 7 #define IMG_DESCR_LENGTH 9 #define MAX_PLANES 8 #define MAX_COLORS (1<=&stack[STACKSIZE]) \ fatal_error("stack overflow"); } #define pop() (*--stackpointer) /* global variables for decompressing routine */ int code_size,clear_code,nbits; int byte_count,ch,bt,end_of_data; #define END_CODE (clear_code+1) #define FIRST (clear_code+2) struct tabentry table[MAXMAX+10]; char stack[STACKSIZE+10]; /* function declarations */ void read_gif(); void read_image(); void decompress_image(); int read_code(); void fatal_error(); void init_image(); void put_pixel(); void read_file(); int read_char(); void seek_file(); void write_file(); void write_long(); char *xmalloc(); void save_raster(); void flip_word(); /* the main program */ void main(argc,argv) int argc; char *argv[]; { if(argc>3) { fprintf(stderr,"Usage: gif2sun [inputfile [outputfile]]\n"); exit(1); } fname=( argc>=2 ? argv[1] : NULL ); read_gif(fname); fname=( argc==3 ? argv[2] : NULL ); save_raster(fname); exit(0); } /* display error message & exit */ void fatal_error(errmsg) char *errmsg; { fprintf(stderr,"gif2sun: "); fprintf(stderr,errmsg,fname); putc('\n',stderr); exit(1); } /* the main GIF-picture reading routine parses the structure of the GIF file, calls read_image() for all images in GIF file */ void read_gif(name) char *name; { char id[6]; struct ScreenDescriptor scrdesc; int n,c,ncolors; int keepgoing=TRUE; if(name) { if((fp=fopen(name,"r"))==NULL) fatal_error("can't open file '%s'"); } else fp=stdin; read_file(fp,id,6); if(strncmp(id,GIF_SIGNATURE,6)) { if(name) fatal_error("'%s' is not a GIF file"); else fatal_error("stdin: not GIF format"); } read_file(fp,(char *)&scrdesc,SCR_DESCR_LENGTH); flip_word(&scrdesc.Width); flip_word(&scrdesc.Height); depth=(scrdesc.PixelFlags & 7) + 1; if(scrdesc.PixelFlags & 0x80) /* global color map */ { ncolors= 1<MAX_COLORS) ncolors=MAX_COLORS; read_file(fp,(char *)color_map,3*ncolors); color_map_used=1; } width=scrdesc.Width; height=scrdesc.Height; width2=(width+1)&(-2); /* even width */ pixmap=(UBYTE *)xmalloc(width2*height); while(keepgoing) /* loop all images in a file */ { while((c=read_char(fp))!=EOF && c!=IMAGE_SEPARATOR && c!=EXTENSION_INTRODUCER && c!=GIF_TERMINATOR); /* skip all other bytes */ switch(c) { case IMAGE_SEPARATOR: read_image(); break; case EXTENSION_INTRODUCER: /* skip extension */ (void)read_char(fp); /* skip function code */ while((n=read_char(fp)) && n!=EOF) seek_file(fp,(long)n,1); break; case GIF_TERMINATOR: case EOF: keepgoing=FALSE; break; } } if(name) fclose(fp); } /* read one image in GIF file reads image descriptor, calls decompress_image() to read the image */ void read_image() { struct ImageDescriptor imdesc; read_file(fp,(char *)&imdesc,IMG_DESCR_LENGTH); flip_word(&imdesc.Left); flip_word(&imdesc.Top); flip_word(&imdesc.Width); flip_word(&imdesc.Height); if(imdesc.PixelFlags & 0x80) { /* This program cannot really handle local color maps but it can skip them anyway. */ fprintf(stderr,"gif2sun: skipping local color map\n"); seek_file(fp,(long)(3*(1 << ( (imdesc.PixelFlags & 7) + 1))),1); } init_image( (int)imdesc.Left,(int)imdesc.Top,(int)imdesc.Width,(int)imdesc.Height, (int)(imdesc.PixelFlags&0x40)); decompress_image(); } /* decompresses LZW-compressed image calls put_pixel note that pixels are compressed, not bytes */ void decompress_image() { int k,fin_char; register int cur_code,max_code; register int old_code,in_code,free_code; register char *stackpointer=stack; code_size=read_char(fp); byte_count=read_char(fp); clear_code=1<=free_code) { cur_code=old_code; push(fin_char); } while(cur_code>=clear_code) { push(table[cur_code].ch); cur_code=table[cur_code].next; } k=fin_char=cur_code; push(k); /* output pixels from stack in reverse order */ while(stackpointer>stack) put_pixel(pop()); table[free_code].ch=k; /* add code */ table[free_code].next=old_code; if(++free_code>=max_code) { if(nbits> (8-bt))&masks[bb]) << (nbits-bl)); bl-=bb; bt-=bb; } return code; } /* swaps the low and high bytes in a 16-bit word this is necessary because GIF uses lo-byte/hi-byte order. */ void flip_word(ptr) UWORD *ptr; { register char a,*c=(char *)ptr; a=c[0];c[0]=c[1];c[1]=a; } /* global variables for image output */ int xpos,ypos,xstart,ystart,xend,yend,lacepass,no_more_pixels; long planepos; /* pixel output initializing routine */ void init_image(left,top,width,height,lace) int left,top,width,height,lace; { xpos=xstart=left; ypos=ystart=top; xend=left+width; yend=top+height; /* check if image fits on screen */ if(xend>width || yend>height) fatal_error("illegal image dimensions"); lacepass = lace ? 1 : 0; no_more_pixels=FALSE; planepos=width2*ypos+xpos; } /* pixel output routine handles GIF interlace scan line order ( note that GIF interlace has nothing to do with Amiga interlace display mode ) */ void put_pixel(c) register int c; { /* arrays for decoding GIF interlace */ static int lace_incr[]={ 0,8,8,4,2 }; /* first element of array not used */ static int lace_strt[]={ 0,0,4,2,1 }; /* 2 first elements not used */ if(no_more_pixels) return; pixmap[planepos++]=c; if(++xpos>=xend) { xpos=xstart; if(lacepass==0) { if(++ypos>=yend) no_more_pixels=TRUE; } else { if((ypos+=lace_incr[lacepass])>=yend) { if(lacepass<4) ypos=ystart+lace_strt[++lacepass]; else no_more_pixels=TRUE; } } planepos=width2*ypos+xpos; } } /* The rasterfile save routine */ void save_raster(name) char *name; { FILE *fp; struct rasterfile header; register int i,j; if(name) { if((fp=fopen(name,"w"))==NULL) fatal_error("can't open output file '%s'"); } else fp=stdout; header.ras_magic=RAS_MAGIC; header.ras_width=width2; header.ras_height=height; header.ras_depth=8; header.ras_length=width2*height; header.ras_type=RT_STANDARD; if(!color_map_used) { header.ras_maptype=RMT_NONE; header.ras_maplength=0; } else { header.ras_maptype=RMT_EQUAL_RGB; header.ras_maplength=3*MAX_COLORS; } write_file(fp,(char *)&header,sizeof(header)); if(color_map_used) { for(i=0;i<3;i++) for(j=0;j=yend) { if(lacepass<4) ypos=ystart+lace_strt[++lacepass]; else no_more_pixels=TRUE; } } planepos=width2*ypos+xpos; } } /* The rasterfile save routine */ void save_raster(name) char *name; { FILE *fp; struct rasterfile header; register int i,j; if(name) { if((fp=fopen(name,"w"))==NULL) fatal_error("can't open output file '%s'"); } else fp=stecompress_image() { int k,fin_char; register int cur_code,max_code; register int old_code,in_code,free_code; register char *stackpointer=stack; code_size=read_char(fp); byte_count=read_char(fp); clear_code=1<=free_code) { cur_code=old_code; push(fin_char); } while(cur_code>=clear_code) { push(table[cur_code].ch); cur_code=table[cur_code].next; } k=fin_char=cur_code; push(k); /* output pixels from stack in reverse order */ while(stackpointer>stack) put_pixel(pop()); table[free_code].ch=k; /* add code */ table[free_code].next=old_code; if(++free_code>=max_code) { if(nbits> (8-bt))&masks[bb]) << (nbits-bl)); bl-=bb; bt-=bb; } return code; } /* swaps the low and high bytes in a 16-bit word this is necessary because GIF uses lo-byte/hi-byte order. */ void flip_word(ptr) UWORD *ptr; { register char a,*c=(char *)ptr; a=c[0