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//
// mxToolKit (c) 1999 by Mete Ciragan
//
// file: mxBmp.cpp
// implementation: all
// last modified: Apr 15 1999, Mete Ciragan
// copyright: The programs and associated files contained in this
// distribution were developed by Mete Ciragan. The programs
// are not in the public domain, but they are freely
// distributable without licensing fees. These programs are
// provided without guarantee or warrantee expressed or
// implied.
// lbmlib.c
#include "mxtk/mxBmp.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
mxImage * mxBmpRead (const char *filename) { int i; FILE *pfile = 0; mxBitmapFileHeader bmfh; mxBitmapInfoHeader bmih; mxBitmapRGBQuad rgrgbPalette[256]; int cbBmpBits; byte *pbBmpBits; byte *pb, *pbPal = 0; int cbPalBytes; int biTrueWidth; mxImage *image = 0;
// File exists?
if ((pfile = fopen (filename, "rb")) == 0) return 0; // Read file header
if (fread (&bmfh, sizeof bmfh, 1/*count*/, pfile) != 1) goto GetOut;
// Bogus file header check
if (!(bmfh.bfReserved1 == 0 && bmfh.bfReserved2 == 0)) goto GetOut;
// Read info header
if (fread (&bmih, sizeof bmih, 1/*count*/, pfile) != 1) goto GetOut;
// Bogus info header check
if (!(bmih.biSize == sizeof bmih && bmih.biPlanes == 1)) goto GetOut;
// Bogus bit depth? Only 8-bit supported.
if (bmih.biBitCount != 8) goto GetOut;
// Bogus compression? Only non-compressed supported.
if (bmih.biCompression != 0) //BI_RGB)
goto GetOut;
// Figure out how many entires are actually in the table
if (bmih.biClrUsed == 0) { bmih.biClrUsed = 256; cbPalBytes = (1 << bmih.biBitCount) * sizeof (mxBitmapRGBQuad); } else { cbPalBytes = bmih.biClrUsed * sizeof (mxBitmapRGBQuad); }
// Read palette (bmih.biClrUsed entries)
if (fread (rgrgbPalette, cbPalBytes, 1/*count*/, pfile) != 1) goto GetOut;
image = new mxImage (); if (!image) goto GetOut;
if (!image->create (bmih.biWidth, bmih.biHeight, 8)) { delete image; goto GetOut; }
pb = (byte *) image->palette;
// Copy over used entries
for (i = 0; i < (int) bmih.biClrUsed; i++) { *pb++ = rgrgbPalette[i].rgbRed; *pb++ = rgrgbPalette[i].rgbGreen; *pb++ = rgrgbPalette[i].rgbBlue; }
// Fill in unused entires will 0,0,0
for (i = bmih.biClrUsed; i < 256; i++) { *pb++ = 0; *pb++ = 0; *pb++ = 0; }
// Read bitmap bits (remainder of file)
cbBmpBits = bmfh.bfSize - ftell (pfile); pb = (byte *) malloc (cbBmpBits * sizeof (byte)); if (pb == 0) { free (pbPal); goto GetOut; }
if (fread (pb, cbBmpBits, 1/*count*/, pfile) != 1) { free (pb); free (pbPal); goto GetOut; } /*
pbBmpBits = malloc(cbBmpBits); if (pbBmpBits == 0) { free (pb); free (pbPal); goto GetOut; } */ pbBmpBits = (byte *) image->data;
// data is actually stored with the width being rounded up to a multiple of 4
biTrueWidth = (bmih.biWidth + 3) & ~3; // reverse the order of the data.
pb += (bmih.biHeight - 1) * biTrueWidth; for(i = 0; i < bmih.biHeight; i++) { memmove (&pbBmpBits[biTrueWidth * i], pb, biTrueWidth); pb -= biTrueWidth; }
pb += biTrueWidth; free (pb);
GetOut: if (pfile) fclose (pfile);
return image; }
bool mxBmpWrite (const char *filename, mxImage *image) { int i; FILE *pfile = 0; mxBitmapFileHeader bmfh; mxBitmapInfoHeader bmih; mxBitmapRGBQuad rgrgbPalette[256]; int cbBmpBits; byte *pbBmpBits; byte *pb = 0; int cbPalBytes; int biTrueWidth;
if (!image || !image->data || !image->palette) return false;
// File exists?
if ((pfile = fopen(filename, "wb")) == 0) return false;
biTrueWidth = ((image->width + 3) & ~3); cbBmpBits = biTrueWidth * image->height; cbPalBytes = 256 * sizeof (mxBitmapRGBQuad);
// Bogus file header check
//bmfh.bfType = MAKEWORD( 'B', 'M' );
bmfh.bfType = (word) (('M' << 8) | 'B'); bmfh.bfSize = sizeof bmfh + sizeof bmih + cbBmpBits + cbPalBytes; bmfh.bfReserved1 = 0; bmfh.bfReserved2 = 0; bmfh.bfOffBits = sizeof bmfh + sizeof bmih + cbPalBytes;
// Write file header
if (fwrite (&bmfh, sizeof bmfh, 1/*count*/, pfile) != 1) { fclose (pfile); return false; }
// Size of structure
bmih.biSize = sizeof bmih; // Width
bmih.biWidth = biTrueWidth; // Height
bmih.biHeight = image->height; // Only 1 plane
bmih.biPlanes = 1; // Only 8-bit supported.
bmih.biBitCount = 8; // Only non-compressed supported.
bmih.biCompression = 0; //BI_RGB;
bmih.biSizeImage = 0;
// huh?
bmih.biXPelsPerMeter = 0; bmih.biYPelsPerMeter = 0;
// Always full palette
bmih.biClrUsed = 256; bmih.biClrImportant = 0; // Write info header
if (fwrite (&bmih, sizeof bmih, 1/*count*/, pfile) != 1) { fclose (pfile); return false; }
// convert to expanded palette
pb = (byte *) image->palette;
// Copy over used entries
for (i = 0; i < (int) bmih.biClrUsed; i++) { rgrgbPalette[i].rgbRed = *pb++; rgrgbPalette[i].rgbGreen = *pb++; rgrgbPalette[i].rgbBlue = *pb++; rgrgbPalette[i].rgbReserved = 0; }
// Write palette (bmih.biClrUsed entries)
cbPalBytes = bmih.biClrUsed * sizeof (mxBitmapRGBQuad); if (fwrite (rgrgbPalette, cbPalBytes, 1/*count*/, pfile) != 1) { fclose (pfile); return false; }
pbBmpBits = (byte *) malloc (cbBmpBits * sizeof (byte)); if (!pbBmpBits) { fclose (pfile); return false; }
pb = (byte *) image->data; // reverse the order of the data.
pb += (image->height - 1) * image->width; for(i = 0; i < bmih.biHeight; i++) { memmove (&pbBmpBits[biTrueWidth * i], pb, image->width); pb -= image->width; }
// Write bitmap bits (remainder of file)
if (fwrite (pbBmpBits, cbBmpBits, 1/*count*/, pfile) != 1) { free (pbBmpBits); fclose (pfile); return false; }
free (pbBmpBits); fclose (pfile);
return true; }
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