/* * pcxtoppm.c - Converts from a PC Paintbrush PCX file to a PPM file. * * Copyright (c) 1990 by Michael Davidson * * 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 file is provided AS IS with no warranties of any kind. The author * shall have no liability with respect to the infringement of copyrights, * trade secrets or any patents by this file or any part thereof. In no * event will the author be liable for any lost revenue or profits or * other special, indirect and consequential damages. * * Modifications by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de) * 20/Apr/94: * - checks if 16-color-palette is completely black -> use standard palette * - "-stdpalette" option to enforce this * - row-by-row operation (PPM output) * 11/Dec/94: * - support for 24bit and 32bit (24bit + 8bit intensity) images * - row-by-row operation (PCX input, for 16-color and truecolor images) * - some code restructuring * 15/Feb/95: * - bugfix for 16 color-images: few bytes allocated for rawrow in some cases * - added sanity checks for cols<->BytesPerLine * 17/Jul/95: * - moved check of 16-color-palette into pcx_16col_to_ppm(), * now checks if it contains only a single color */ #include "ppm.h" #include "shhopt.h" #define PCX_MAGIC 0x0a /* PCX magic number */ #define PCX_HDR_SIZE 128 /* size of PCX header */ #define PCX_256_COLORS 0x0c /* magic number for 256 colors */ #define PCX_MAXVAL (pixval)255 /* prototypes */ static void pcx_16col_to_ppm ARGS((FILE *ifp, int cols, int rows, int BytesPerLine, int BitsPerPixel, int Planes, pixel *cmap)); static void pcx_256col_to_ppm ARGS((FILE *ifp, int cols, int rows, int BytesPerLine)); static void pcx_truecol_to_ppm ARGS((FILE *ifp, int cols, int rows, int BytesPerLine, int Planes)); static void GetPCXRow ARGS((FILE *ifp, unsigned char *pcxrow, int bytesperline)); static void pcx_planes_to_pixels ARGS(( unsigned char *pixels, unsigned char *bitplanes, int bytesperline, int planes, int bitsperpixel )); static void pcx_unpack_pixels ARGS(( unsigned char *pixels, unsigned char *bitplanes, int bytesperline, int planes, int bitsperpixel )); static int GetByte ARGS(( FILE *fp )); /* standard palette */ static unsigned char const StdRed[] = { 0, 255, 0, 0, 170, 170, 170, 170, 85, 85, 85, 85, 255, 255, 255, 255 }; static unsigned char const StdGreen[] = { 0, 255, 170, 170, 0, 0, 170, 170, 85, 85, 255, 255, 85, 85, 255, 255 }; static unsigned char const StdBlue[] = { 0, 255, 0, 170, 0, 170, 0, 170, 85, 255, 85, 255, 85, 255, 85, 255 }; static pixel stdPalette[16]; static void generateStdPalette(void) { int i; for (i = 0; i < 16; i++) PPM_ASSIGN(stdPalette[i], StdRed[i], StdGreen[i], StdBlue[i]); } struct cmdlineInfo { /* All the information the user supplied in the command line, in a form easy for the program to use. */ const char *inputFilespec; /* '-' if stdin */ unsigned int verbose; unsigned int stdpalette; }; static void parseCommandLine ( int argc, char ** argv, struct cmdlineInfo *cmdlineP ) { /*---------------------------------------------------------------------------- parse program command line described in Unix standard form by argc and argv. Return the information in the options as *cmdlineP. If command line is internally inconsistent (invalid options, etc.), issue error message to stderr and abort program. Note that the strings we return are stored in the storage that was passed to us as the argv array. We also trash *argv. -----------------------------------------------------------------------------*/ optEntry *option_def = malloc( 100*sizeof( optEntry ) ); /* Instructions to optParseOptions3 on how to parse our options. */ optStruct3 opt; unsigned int option_def_index; option_def_index = 0; /* incremented by OPTENT3 */ OPTENT3(0, "stdpalette", OPT_FLAG, NULL, &cmdlineP->stdpalette, 0 ); OPTENT3(0, "verbose", OPT_FLAG, NULL, &cmdlineP->verbose, 0 ); opt.opt_table = option_def; opt.short_allowed = FALSE; /* We have no short (old-fashioned) options */ opt.allowNegNum = FALSE; /* We have no parms that are negative numbers */ optParseOptions3( &argc, argv, opt, sizeof(opt), 0 ); /* Uses and sets argc, argv, and some of *cmdline_p and others. */ if (argc-1 < 1) cmdlineP->inputFilespec = "-"; else if (argc-1 == 1) cmdlineP->inputFilespec = argv[1]; else pm_error("Program takes at most one argument " "(input file specification). You specified %d", argc-1); } struct pcxHeader { int Version; /* Xmin, Ymin, Xmax, and Ymax are positions in some field (in units of pixels) of the edges of the image. They may be negative. You can derive the image width and height from these. */ short Xmin; short Ymin; short Xmax; short Ymax; short Encoding; short Planes; short BitsPerPixel; short BytesPerLine; /* Number of decompressed bytes each plane of each row of the image takes. Due to padding (this is always an even number), there may be garbage on the right end that isn't part of the image. */ short PaletteInfo; short HorizontalResolution; short VerticalResolution; pixel cmap16[16]; }; static void readInt(FILE * const ifP, short * const retvalP) { /*---------------------------------------------------------------------------- Read a 2-byte little-endian word from the file. -----------------------------------------------------------------------------*/ int rc; rc = pm_readlittleshort(ifP, retvalP); if (rc != 0) pm_error("EOF/error reading integer from input file."); } static void readPcxHeader(FILE * const ifP, struct pcxHeader * const pcxHeaderP) { /*---------------------------------------------------------------------------- Read the PCX header -----------------------------------------------------------------------------*/ if (GetByte(ifP) != PCX_MAGIC) pm_error("bad magic number - not a PCX file"); pcxHeaderP->Version = GetByte(ifP); /* get version # */ pcxHeaderP->Encoding = GetByte(ifP); if (pcxHeaderP->Encoding != 1) /* check for PCX run length encoding */ pm_error("unknown encoding scheme: %d", pcxHeaderP->Encoding); pcxHeaderP->BitsPerPixel= GetByte(ifP); readInt(ifP, &pcxHeaderP->Xmin); readInt(ifP, &pcxHeaderP->Ymin); readInt(ifP, &pcxHeaderP->Xmax); readInt(ifP, &pcxHeaderP->Ymax); if (pcxHeaderP->Xmax < pcxHeaderP->Xmin) pm_error("Invalid PCX input: minimum X value (%d) is greater than " "maximum X value (%d).", pcxHeaderP->Xmin, pcxHeaderP->Xmax); if (pcxHeaderP->Ymax < pcxHeaderP->Ymin) pm_error("Invalid PCX input: minimum Y value (%d) is greater than " "maximum Y value (%d).", pcxHeaderP->Ymin, pcxHeaderP->Ymax); readInt(ifP, &pcxHeaderP->HorizontalResolution); readInt(ifP, &pcxHeaderP->VerticalResolution); { int i; /* * get the 16-color color map */ for (i = 0; i < 16; i++) { int r, g, b; r = GetByte(ifP); g = GetByte(ifP); b = GetByte(ifP); PPM_ASSIGN(pcxHeaderP->cmap16[i], r, g, b); } } GetByte(ifP); /* skip reserved byte */ pcxHeaderP->Planes = GetByte(ifP); /* # of color planes */ readInt(ifP, &pcxHeaderP->BytesPerLine); readInt(ifP, &pcxHeaderP->PaletteInfo); /* Read past a bunch of reserved space in the header. We have read 70 bytes of the header so far. We would just seek here, except that we want to work with unseekable (e.g. pipe input). */ { unsigned int pos; for (pos = 70; pos < PCX_HDR_SIZE; ++pos) GetByte(ifP); } } static void reportPcxHeader(struct pcxHeader const pcxHeader) { pm_message("Version: %d", pcxHeader.Version); pm_message("BitsPerPixel: %d", pcxHeader.BitsPerPixel); pm_message("Xmin: %d Ymin: %d Xmax: %d Ymax: %d", pcxHeader.Xmin, pcxHeader.Ymin, pcxHeader.Xmax, pcxHeader.Ymax); pm_message("Planes: %d BytesPerLine: %d PaletteInfo: %d", pcxHeader.Planes, pcxHeader.BytesPerLine, pcxHeader.PaletteInfo); } int main(int argc, char *argv[]) { FILE *ifP; struct cmdlineInfo cmdline; struct pcxHeader pcxHeader; int Width, Height; pixel *cmap16; ppm_init( &argc, argv ); generateStdPalette(); parseCommandLine(argc, argv, &cmdline); ifP = pm_openr(cmdline.inputFilespec); readPcxHeader(ifP, &pcxHeader); if (cmdline.verbose) reportPcxHeader(pcxHeader); Width = (pcxHeader.Xmax - pcxHeader.Xmin) + 1; Height = (pcxHeader.Ymax - pcxHeader.Ymin) + 1; if (cmdline.stdpalette) cmap16 = stdPalette; else cmap16 = pcxHeader.cmap16; ppm_writeppminit(stdout, Width, Height, PCX_MAXVAL, 0); switch (pcxHeader.BitsPerPixel) { case 1: if(pcxHeader.Planes >= 1 && pcxHeader.Planes <= 4) pcx_16col_to_ppm(ifP, Width, Height, pcxHeader.BytesPerLine, pcxHeader.BitsPerPixel, pcxHeader.Planes, cmap16); else goto fail; break; case 2: case 4: if (pcxHeader.Planes == 1) pcx_16col_to_ppm(ifP, Width, Height, pcxHeader.BytesPerLine, pcxHeader.BitsPerPixel, pcxHeader.Planes, cmap16); else goto fail; break; case 8: switch(pcxHeader.Planes) { case 1: pcx_256col_to_ppm(ifP, Width, Height, pcxHeader.BytesPerLine); break; case 3: case 4: pcx_truecol_to_ppm(ifP, Width, Height, pcxHeader.BytesPerLine, pcxHeader.Planes); break; default: goto fail; } break; default: fail: pm_error("can't handle %d bits per pixel image with %d planes", pcxHeader.BitsPerPixel, pcxHeader.Planes); } pm_close(ifP); exit(0); } static void pcx_16col_to_ppm(ifp, cols, rows, BytesPerLine, BitsPerPixel, Planes, cmap) FILE *ifp; int cols, rows; int BytesPerLine, BitsPerPixel, Planes; pixel *cmap; /* colormap from header */ { int row, col, rawcols, colors; unsigned char *pcxrow, *rawrow; pixel *ppmrow; short palette_ok = 0; #ifdef DEBUG pm_message("16 color -> ppm"); #endif /* check if palette is ok */ colors = (1 << BitsPerPixel) * (1 << Planes); for( col = 0; col < colors-1; col++ ) { if( !PPM_EQUAL(cmap[col], cmap[col+1]) ) { palette_ok = 1; break; } } if( !palette_ok ) { pm_message("warning - useless header palette, " "using builtin standard palette"); for( col = 0; col < colors; col++ ) PPM_ASSIGN(cmap[col], StdRed[col], StdGreen[col], StdBlue[col]); } /* BytesPerLine should be >= BitsPerPixel * cols / 8 */ rawcols = BytesPerLine * 8 / BitsPerPixel; if( cols > rawcols ) { pm_message("warning - BytesPerLine = %d, " "truncating image to %d pixels", BytesPerLine, rawcols); cols = rawcols; } pcxrow = (unsigned char *) pm_allocrow(Planes * BytesPerLine, sizeof(unsigned char)); rawrow = (unsigned char *)pm_allocrow(rawcols, sizeof(unsigned char)); ppmrow = ppm_allocrow(cols); for( row = 0; row < rows; row++ ) { GetPCXRow(ifp, pcxrow, Planes * BytesPerLine); if (Planes == 1) pcx_unpack_pixels(rawrow, pcxrow, BytesPerLine, Planes, BitsPerPixel); else pcx_planes_to_pixels(rawrow, pcxrow, BytesPerLine, Planes, BitsPerPixel); for( col = 0; col < cols; col++ ) ppmrow[col] = cmap[rawrow[col]]; ppm_writeppmrow(stdout, ppmrow, cols, PCX_MAXVAL, 0); } #ifdef DEBUG pm_message("done!"); #endif ppm_freerow(ppmrow); pm_freerow((char*)rawrow); pm_freerow((void*)pcxrow); } static void pcx_256col_to_ppm(ifp, cols, rows, BytesPerLine) FILE *ifp; int cols, rows; int BytesPerLine; { pixel colormap[256]; pixel *ppmrow; unsigned char **image; unsigned char colormapSignature; int row, col; #ifdef DEBUG pm_message("256 color -> ppm, reading index array..."); #endif if( cols > BytesPerLine ) { pm_message("warning - BytesPerLine = %d, " "truncating image to %d pixels", BytesPerLine, BytesPerLine); cols = BytesPerLine; } image = (unsigned char **)pm_allocarray(BytesPerLine, rows, sizeof(unsigned char)); for( row = 0; row < rows; row++ ) GetPCXRow(ifp, image[row], BytesPerLine); #ifdef DEBUG pm_message("ok, now reading colormap..."); #endif /* * 256 color images have their color map at the end of the file * preceeded by a magic byte */ colormapSignature = GetByte(ifp); if (colormapSignature != PCX_256_COLORS) pm_error("bad color map signature. In a 1-plane PCX image " "such as this, we expect a magic number of %u in the byte " "following the raster, to introduce the color map. " "Instead, this image has %u.", PCX_256_COLORS, colormapSignature); else { unsigned int colorIndex; for(colorIndex = 0; colorIndex < 256; ++colorIndex) { int r, g, b; r = GetByte(ifp); g = GetByte(ifp); b = GetByte(ifp); PPM_ASSIGN(colormap[colorIndex], r, g, b); } } #ifdef DEBUG pm_message("ok, converting..."); #endif ppmrow = ppm_allocrow(cols); for( row = 0; row < rows; row++ ) { for( col = 0; col < cols; col++ ) ppmrow[col] = colormap[image[row][col]]; ppm_writeppmrow(stdout, ppmrow, cols, PCX_MAXVAL, 0); } #ifdef DEBUG pm_message("done!"); #endif ppm_freerow(ppmrow); pm_freearray((void *)image, rows); } static void pcx_truecol_to_ppm(ifp, cols, rows, BytesPerLine, Planes) FILE *ifp; int cols, rows; int BytesPerLine, Planes; { unsigned char *redrow, *greenrow, *bluerow, *intensityrow; pixel *ppmrow; int row, col; int r, g, b, i; #ifdef DEBUG pm_message("%dbit truecolor -> ppm", Planes * 8); #endif if( cols > BytesPerLine ) { pm_message("warning - BytesPerLine = %d, " "truncating image to %d pixels", BytesPerLine, BytesPerLine); cols = BytesPerLine; } redrow = (unsigned char *) pm_allocrow(BytesPerLine, sizeof(unsigned char*)); greenrow = (unsigned char *) pm_allocrow(BytesPerLine, sizeof(unsigned char*)); bluerow = (unsigned char *) pm_allocrow(BytesPerLine, sizeof(unsigned char*)); if( Planes == 4 ) intensityrow = (unsigned char *) pm_allocrow(BytesPerLine, sizeof(unsigned char*)); else intensityrow = (unsigned char *)NULL; ppmrow = ppm_allocrow(cols); for( row = 0; row < rows; row++ ) { GetPCXRow(ifp, redrow, BytesPerLine); GetPCXRow(ifp, greenrow, BytesPerLine); GetPCXRow(ifp, bluerow, BytesPerLine); if( intensityrow ) GetPCXRow(ifp, intensityrow, BytesPerLine); for( col = 0; col < cols; col++ ) { r = redrow[col]; g = greenrow[col]; b = bluerow[col]; if( intensityrow ) { i = intensityrow[col]; r = r * i / 256; g = g * i / 256; b = b * i / 256; } PPM_ASSIGN(ppmrow[col], r, g, b); } ppm_writeppmrow(stdout, ppmrow, cols, PCX_MAXVAL, 0); } #ifdef DEBUG pm_message("done!"); #endif ppm_freerow(ppmrow); if( intensityrow ) pm_freerow((void*)intensityrow); pm_freerow((void*)bluerow); pm_freerow((void*)greenrow); pm_freerow((void*)redrow); } /* * convert multi-plane format into 1 pixel per byte */ static void pcx_planes_to_pixels(pixels, bitplanes, bytesperline, planes, bitsperpixel) unsigned char *pixels; unsigned char *bitplanes; int bytesperline; int planes; int bitsperpixel; { int i, j; int npixels; unsigned char *p; if (planes > 4) pm_error("can't handle more than 4 planes" ); if (bitsperpixel != 1) pm_error("can't handle more than 1 bit per pixel" ); /* * clear the pixel buffer */ npixels = (bytesperline * 8) / bitsperpixel; p = pixels; while (--npixels >= 0) *p++ = 0; /* * do the format conversion */ for (i = 0; i < planes; i++) { int pixbit, bits, mask; p = pixels; pixbit = (1 << i); for (j = 0; j < bytesperline; j++) { bits = *bitplanes++; for (mask = 0x80; mask != 0; mask >>= 1, p++) if (bits & mask) *p |= pixbit; } } } /* * convert packed pixel format into 1 pixel per byte */ static void pcx_unpack_pixels(pixels, bitplanes, bytesperline, planes, bitsperpixel) unsigned char *pixels; unsigned char *bitplanes; int bytesperline; int planes; int bitsperpixel; { register int bits; if (planes != 1) pm_error("can't handle packed pixels with more than 1 plane" ); #if 0 if (bitsperpixel == 8) { while (--bytesperline >= 0) *pixels++ = *bitplanes++; } else #endif if (bitsperpixel == 4) { while (--bytesperline >= 0) { bits = *bitplanes++; *pixels++ = (bits >> 4) & 0x0f; *pixels++ = (bits ) & 0x0f; } } else if (bitsperpixel == 2) { while (--bytesperline >= 0) { bits = *bitplanes++; *pixels++ = (bits >> 6) & 0x03; *pixels++ = (bits >> 4) & 0x03; *pixels++ = (bits >> 2) & 0x03; *pixels++ = (bits ) & 0x03; } } else if (bitsperpixel == 1) { while (--bytesperline >= 0) { bits = *bitplanes++; *pixels++ = ((bits & 0x80) != 0); *pixels++ = ((bits & 0x40) != 0); *pixels++ = ((bits & 0x20) != 0); *pixels++ = ((bits & 0x10) != 0); *pixels++ = ((bits & 0x08) != 0); *pixels++ = ((bits & 0x04) != 0); *pixels++ = ((bits & 0x02) != 0); *pixels++ = ((bits & 0x01) != 0); } } else pm_error("pcx_unpack_pixels - can't handle %d bits per pixel", bitsperpixel); } static int rowsRead=0; static int GetByte(FILE * const fp) { int c; if ((c = fgetc(fp)) == EOF) pm_error("unexpected end of file" ); return c; } /* * read a single row encoded row, handles encoding across rows */ static void GetPCXRow(FILE * const ifP, unsigned char * const pcxrow, int const bytesperline) { /*---------------------------------------------------------------------------- Read one row from the PCX raster. The PCX raster is run length encoded as follows: If the upper two bits of a byte are 11, the lower 6 bits are a repetition count for the raster byte that follows. If the upper two bits are not 11, the byte _is_ a raster byte, with repetition count 1. A run can't span rows, but it can span planes within a row. That's why 'repetitionsLeft' and 'c' are static variables in this subroutine. -----------------------------------------------------------------------------*/ static int repetitionsLeft = 0; static int c; int bytesGenerated; bytesGenerated = 0; while( bytesGenerated < bytesperline ) { if(repetitionsLeft > 0) { pcxrow[bytesGenerated++] = c; --repetitionsLeft; } else { if (rowsRead==241) pm_message("Reading Byte %ld", ftell(ifP)); c = GetByte(ifP); if ((c & 0xc0) != 0xc0) /* This is a 1-shot byte, not a repetition count */ pcxrow[bytesGenerated++] = c; else { /* This is a repetition count for the following byte */ repetitionsLeft = c & 0x3f; if (rowsRead == 241) pm_message("doing run of %d of Byte %ld in Row 241", repetitionsLeft, ftell(ifP)); c = GetByte(ifP); } } } rowsRead++; }