/***************************************************************************** * * iff.c * * from DKBTrace (c) 1990 David Buck * * This file implements a simple IFF format file reader. * * This software is freely distributable. The source and/or object code may be * copied or uploaded to communications services so long as this notice remains * at the top of each file. If any changes are made to the program, you must * clearly indicate in the documentation and in the programs startup message * who it was who made the changes. The documentation should also describe what * those changes were. This software may not be included in whole or in * part into any commercial package without the express written consent of the * author. It may, however, be included in other public domain or freely * distributed software so long as the proper credit for the software is given. * * This software is provided as is without any guarantees or warranty. Although * the author has attempted to find and correct any bugs in the software, he * is not responsible for any damage caused by the use of the software. The * author is under no obligation to provide service, corrections, or upgrades * to this package. * * Despite all the legal stuff above, if you do find bugs, I would like to hear * about them. Also, if you have any comments or questions, you may contact me * at the following address: * * David Buck * 22C Sonnet Cres. * Nepean Ontario * Canada, K2H 8W7 * * I can also be reached on the following bulleton boards: * * ATX (613) 526-4141 * OMX (613) 731-3419 * Mystic (613) 731-0088 or (613) 731-6698 * * Fidonet: 1:163/109.9 * Internet: David_Buck@Carleton.CA * * IBM Port by Aaron A. Collins. Aaron may be reached on the following BBS'es: * * Lattice BBS (708) 916-1200 * The Information Exchange BBS (708) 945-5575 * Stillwaters BBS (708) 403-2826 * *****************************************************************************/ #include "frame.h" #include "dkbproto.h" static IMAGE_COLOUR *iff_colour_map; static int colourmap_size; static CHUNK_HEADER Chunk_Header; #define FORM 0x464f524dL #define ILBM 0x494c424dL #define BMHD 0x424d4844L #define CAMG 0x43414d47L #define CMAP 0x434d4150L #define BODY 0x424f4459L #define CMPNONE 0 #define HAM 0x800 void iff_error () { printf ("Invalid iff file\n"); exit(1); } int read_byte(f) FILE *f; { int c; if ((c = getc(f)) == EOF) iff_error(); return (c); } int read_word(f) FILE *f; { int result; result = read_byte(f)*256; result += read_byte(f); return (result); } long read_long(f) FILE *f; { int i; long result; result = 0; for (i = 0 ; i < 4 ; i++) result = result * 256 + read_byte(f); return (result); } void Read_Chunk_Header (f, dest) FILE *f; CHUNK_HEADER *dest; { dest->name = read_long(f); dest->size = read_long(f); } void read_iff_image(Image, filename) IMAGE *Image; char *filename; { FILE *f; unsigned char **row_bytes; int c, i, j, k, creg, index, nBytes, nBytesRead, nPlanes, compression, mask, byte_index, count, viewmodes; int Previous_Red, Previous_Green, Previous_Blue; if ((f = fopen(filename, "rb")) == NULL) { printf ("Cannot open IFF file %s\n", filename); exit(1); } Previous_Red = Previous_Green = Previous_Blue = 0; viewmodes = 0; while (1) { Read_Chunk_Header(f, &Chunk_Header); switch ((int) Chunk_Header.name) { case FORM: if (read_long(f) != ILBM) iff_error(); break; case BMHD: Image->iwidth = read_word(f); Image->width = (DBL)Image->iwidth; Image->iheight = read_word(f); Image->height = (DBL)Image->iheight; read_word(f); /* x position ignored */ read_word(f); /* y position ignored */ nPlanes = read_byte(f); colourmap_size = 1<iwidth+7)/8)) == NULL) { printf ("Not enough memory\n"); exit(1); } if (((Image->red = (unsigned char *) malloc(Image->iwidth*Image->iheight))==NULL) || ((Image->green = (unsigned char *) malloc(Image->iwidth*Image->iheight))==NULL) || ((Image->blue = (unsigned char *) malloc(Image->iwidth*Image->iheight))==NULL)) { printf ("Cannot allocate memory for picture\n"); exit(1); } for (i = 0 ; i < Image->iheight ; i++) { for (j = 0 ; j < nPlanes ; j++) if (compression == CMPNONE) { for (k = 0 ; k < (Image->iwidth+7)/8 ; k++) row_bytes[j][k] = read_byte(f); if ((Image->iwidth & 7) != 0) read_byte(f); } else { nBytes = 0; nBytesRead = 0; while (nBytes != (Image->iwidth+7)/8) { c = read_byte(f); nBytesRead++; if ((c >= 0) && (c <= 127)) for (k = 0 ; k <= c ; k++) row_bytes[j][nBytes++] = read_byte(f); else if ((c >= 129) && (c <= 255)) { count = 257-c; c = read_byte(f); nBytesRead++; for (k = 0 ; k < count ; k++) row_bytes[j][nBytes++] = c; } } } mask = 0x80; byte_index = 0; for (j = 0 ; j < Image->iwidth ; j++) { creg = 0; for (k = nPlanes-1 ; k >= 0 ; k--) if (row_bytes[k][byte_index] & mask) creg = creg*2 + 1; else creg *= 2; index = (Image->iheight-i-1)*Image->iwidth + j; if (viewmodes & HAM) { switch (creg >> 4) { case 0: Previous_Red = Image->red[index] = iff_colour_map[creg].Red; Previous_Green = Image->green[index] = iff_colour_map[creg].Green; Previous_Blue = Image->blue[index] = iff_colour_map[creg].Blue; break; case 1: Image->red[index] = Previous_Red; Image->green[index] = Previous_Green; Previous_Blue = Image->blue[index] = ((creg & 0xf)<<4) + (creg&0xf); break; case 2: Previous_Red = Image->red[index] = ((creg & 0xf)<<4) + (creg&0xf); Image->green[index] = Previous_Green; Image->blue[index] = Previous_Blue; break; case 3: Image->red[index] = Previous_Red; Previous_Green = Image->green[index] = ((creg & 0xf)<<4) + (creg&0xf); Image->blue[index] = Previous_Blue; break; } } else { Image->red[index] = iff_colour_map[creg].Red; Image->green[index] = iff_colour_map[creg].Green; Image->blue[index] = iff_colour_map[creg].Blue; } mask >>= 1; if (mask == 0) { mask = 0x80; byte_index++; } } } free (row_bytes); fclose (f); return; default: for (i = 0 ; i < Chunk_Header.size ; i++) if (getc(f) == EOF) iff_error(); break; } } }