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Some formatting.
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Chris Anders committed Jan 21, 2013
1 parent 71bebf6 commit d4198bb
Showing 1 changed file with 122 additions and 122 deletions.
244 changes: 122 additions & 122 deletions pset4/bmp/resize.c
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Original file line number Diff line number Diff line change
Expand Up @@ -6,133 +6,133 @@
*
* Resizes a BMP by a specified factor.
***************************************************************************/

#include <stdio.h>
#include <stdlib.h>

#include "bmp.h"

int main(int argc, char* argv[])
{
// ensure proper usage
if (argc != 4)
{
printf("Usage:resize n infile outfile\n");
return 1;
}
// Check the resize factor
int factor = atoi(argv[1]);
if(factor < 0 || factor > 100)
{
printf("The resize factor should be a positive integer <= 100.\n");
return 2;
}

// remember filenames and factor
char* infile = argv[2];
char* outfile = argv[3];

// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("Could not open %s.\n", infile);
return 3;
}

// open output file
FILE* outptr = fopen(outfile, "w");
if (outptr == NULL)
{
fclose(inptr);
fprintf(stderr, "Could not create %s.\n", outfile);
return 4;
}

// 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;
}

// construct bitmap headers for the outfile
BITMAPFILEHEADER out_bf;
BITMAPINFOHEADER out_bi;
out_bf = bf;
out_bi = bi;
out_bi.biWidth = bi.biWidth * factor;
out_bi.biHeight = bi.biHeight * factor;

// determine padding for scanlines
// Needed for SizeImage calculation
int in_padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
int out_padding = (4 - (out_bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;

// Calculate file and image size
// Kudos for the folks at https://code.google.com/p/kupl09/ for suggesting the formula for
// biSizeImage calculation.
out_bf.bfSize = 54 + out_bi.biWidth * abs(out_bi.biHeight) * 3 + abs(out_bi.biHeight) * out_padding;
out_bi.biSizeImage = ((((out_bi.biWidth * out_bi.biBitCount) + 31) & ~31) / 8) * abs(out_bi.biHeight);

// write outfile's BITMAPFILEHEADER
fwrite(&out_bf, sizeof(BITMAPFILEHEADER), 1, outptr);

// write outfile's BITMAPINFOHEADER
fwrite(&out_bi, sizeof(BITMAPINFOHEADER), 1, outptr);

for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
// Write each line factor-times
for(int n = 0; n < factor; n++)
{
// 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 RGB triple to outfile
for(int m = 0; m < factor; m++)
{
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}

// skip over padding in infile
fseek(inptr, in_padding, SEEK_CUR);

// then add it to outfile
for (int k = 0; k <out_padding; k++)
fputc(0x00, outptr);

fseek(inptr, -(bi.biWidth * 3 + in_padding ), SEEK_CUR);

}
fseek(inptr, bi.biWidth*3+in_padding, SEEK_CUR);
}

// close infile
fclose(inptr);

// close outfile
fclose(outptr);

// that's all folks
return 0;
// ensure proper usage
if (argc != 4)
{
printf("Usage:resize n infile outfile\n");
return 1;
}

// Check the resize factor
int factor = atoi(argv[1]);
if(factor < 0 || factor > 100)
{
printf("The resize factor should be a positive integer <= 100.\n");
return 2;
}

// remember filenames and factor
char* infile = argv[2];
char* outfile = argv[3];

// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("Could not open %s.\n", infile);
return 3;
}

// open output file
FILE* outptr = fopen(outfile, "w");
if (outptr == NULL)
{
fclose(inptr);
fprintf(stderr, "Could not create %s.\n", outfile);
return 4;
}

// 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;
}

// construct bitmap headers for the outfile
BITMAPFILEHEADER out_bf;
BITMAPINFOHEADER out_bi;
out_bf = bf;
out_bi = bi;
out_bi.biWidth = bi.biWidth * factor;
out_bi.biHeight = bi.biHeight * factor;

// determine padding for scanlines
// Needed for SizeImage calculation
int in_padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
int out_padding = (4 - (out_bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;

// Calculate file and image size
// Kudos for the folks at https://code.google.com/p/kupl09/ for suggesting the formula for
// biSizeImage calculation.
out_bf.bfSize = 54 + out_bi.biWidth * abs(out_bi.biHeight) * 3 + abs(out_bi.biHeight) * out_padding;
out_bi.biSizeImage = ((((out_bi.biWidth * out_bi.biBitCount) + 31) & ~31) / 8) * abs(out_bi.biHeight);

// write outfile's BITMAPFILEHEADER
fwrite(&out_bf, sizeof(BITMAPFILEHEADER), 1, outptr);

// write outfile's BITMAPINFOHEADER
fwrite(&out_bi, sizeof(BITMAPINFOHEADER), 1, outptr);

for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
// Write each line factor-times
for(int n = 0; n < factor; n++)
{
// 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 RGB triple to outfile
for(int m = 0; m < factor; m++)
{
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}

// skip over padding in infile
fseek(inptr, in_padding, SEEK_CUR);

// then add it to outfile
for (int k = 0; k <out_padding; k++)
fputc(0x00, outptr);

fseek(inptr, -(bi.biWidth * 3 + in_padding ), SEEK_CUR);

}
fseek(inptr, bi.biWidth*3+in_padding, SEEK_CUR);
}

// close infile
fclose(inptr);

// close outfile
fclose(outptr);

// that's all folks
return 0;
}

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