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@chrisdel101
Last active Mar 22, 2018
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What would you like to do?
I mean redo the code entirely
#include <stdio.h>
#include <stdlib.h>
#include "bmp.h"
int main(int argc, char *argv[])
{
// ensure proper usage
if (argc != 4)
{
fprintf(stderr, "Usage: copy infile outfile\n");
return 1;
}
int n = atoi(argv[1]);
// remember filenames
char *infile = argv[2];
char *outfile = argv[3];
// open input file
FILE *inptr = fopen(infile, "r");
if (inptr == NULL)
{
fprintf(stderr, "Could not open %s.\n", infile);
return 2;
}
// open output file
FILE *outptr = fopen(outfile, "w");
if (outptr == NULL)
{
fclose(inptr);
fprintf(stderr, "Could not create %s.\n", outfile);
return 3;
}
// read infile's BITMAPFILEHEADER
BITMAPFILEHEADER bf;
fread(&bf, sizeof(BITMAPFILEHEADER), 1, inptr);
// read infile's BITMAPINFOHEADER
BITMAPINFOHEADER bi;
fread(&bi, sizeof(BITMAPINFOHEADER), 1, inptr);
// ensure infile is (likely) a 24-bit uncompressed BMP 4.0
if (bf.bfType != 0x4d42 || bf.bfOffBits != 54 || bi.biSize != 40 ||
bi.biBitCount != 24 || bi.biCompression != 0)
{
fclose(outptr);
fclose(inptr);
fprintf(stderr, "Unsupported file format.\n");
return 4;
}
// make new headers
BITMAPFILEHEADER bf2 = bf;
BITMAPINFOHEADER bi2 = bi;
// new width = old width * n
bi2.biWidth = bi.biWidth *= n;
// new height = old height * n
bi2.biHeight = bi.biHeight *= n;
int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// new padding uses bi2 width
int newPadding = (4 - (bi2.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// new biSizeIMage use new width, and new padding
bi2.biSizeImage = ((sizeof(RGBTRIPLE) * bi2.biWidth) + newPadding) * abs(bi2.biHeight);
// new bf size uses new biSize image and sizeof both new headers
bf2.bfSize = bi2.biSizeImage + sizeof(bf2) + sizeof(bi2);
// write outfile's BITMAPFILEHEADER
fwrite(&bf2, sizeof(BITMAPFILEHEADER), 1, outptr);
// write outfile's BITMAPINFOHEADER
fwrite(&bi2, sizeof(BITMAPINFOHEADER), 1, outptr);
// put pixels in an array - 1000 just to get past the trouble
RGBTRIPLE* arr = malloc(1000* sizeof(RGBTRIPLE));
int arrayIndex = 0;
// iterate over infile's scanlines
for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
// iterate over pixels in scanline
for (int j = 0; j < bi.biWidth; j++)
{
// temporary storage
RGBTRIPLE triple;
// read RGB triple from infile
fread(&triple, sizeof(RGBTRIPLE), 1, inptr);
// write each triple into array above
for(int k = 0;k < n;k++){
arrayIndex++;
arr[arrayIndex] = triple;
// printf("k%i", k);
// printf("%i", arrayIndex);
}
}
arrayIndex = 0;
// iterate n times, once equals a row
for(int row = 0;row < n; row++){
printf("row:%i\n", row);
//write to new width
for(int item = 0;item < bi2.biWidth;item++){
printf("item:%i\n", item);
fwrite(&arr, sizeof(RGBTRIPLE), 1, outptr);
}
if(newPadding > 0){
for (int padCount = 0; padCount < newPadding; padCount++)
{
// padding take width of file (width * n)
fputc(0x00, outptr);
}
}
// arrayIndex = 0;
}
fseek(inptr, padding, SEEK_CUR);
}
// close infile
fclose(inptr);
// close outfile
fclose(outptr);
free(arr);
// success
return 0;
}
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