/**
* resize.c
*
* Computer Science 50
* Problem Set 4
*
* Resizes a 24-bit uncompressed bmp by a factor of n
*/
#include <stdio.h>
#include <stdlib.h>
#include "bmp.h"
int main(int argc, char* argv[])
{
// ensure proper usage
if (argc != 4 || atoi(argv[1]) > 100 || atoi(argv[1]) < 1)
{
printf("Usage: ./resize n infile outfile, where n is greater than 0 and less than or equal to 100\n");
return 1;
}
// remember filenames
char* infile = argv[2];
char* outfile = argv[3];
int n = atoi(argv[1]);
// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("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;
}
int inPadding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4; // Calculates input padding before rewriting header files so I can use it to scan accurately over input file
// resize BITMAPFILEHEADER
bi.biHeight = bi.biHeight * n; // Multiply the height by n
bi.biWidth = bi.biWidth * n; // Multiplies the width by n
// determine padding for scanlines
int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// Determine the SizeImage after the padding is set which requires biWidth be set; normally SizeImage would be right after width
bi.biSizeImage = bi.biWidth * abs(bi.biHeight) * sizeof(RGBTRIPLE) + padding * abs(bi.biHeight);
bf.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + bi.biSizeImage; // concentrates just on the size of the bitmap, subtracting out the headers, multiplies by n to expand number of pixels, multiples by the number of bytes per pixel (the number of bytes per pixel)
// write outfile's BITMAPFILEHEADER
fwrite(&bf, sizeof(BITMAPFILEHEADER), 1, outptr);
// write outfile's BITMAPINFOHEADER
fwrite(&bi, sizeof(BITMAPINFOHEADER), 1, outptr);
// iterate over infile's scanlines
for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
for (int m = 0; m < n; m++)
{
// iterate over pixels in scanline
for (int j = 0; j < bi.biWidth/n; j++)
{
// temporary storage
RGBTRIPLE triple;
// read RGB triple from infile
fread(&triple, sizeof(RGBTRIPLE), 1, inptr);
for (int l = 0; l < n; l++)
{
// write RGB triple to outfile
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}
fseek(inptr, inPadding, SEEK_CUR);
for (int k = 0; k < padding; k++) // Adds padding to each row
{
fputc(0x00, outptr);
}
if(m < (n-1))
{
fseek(inptr, -(bi.biWidth/n * sizeof(RGBTRIPLE) + inPadding), SEEK_CUR); // Resets the INPUT file selector location to the beginning of the row
}
}
}
// close infile
fclose(inptr);
// close outfile
fclose(outptr);
// that's all folks
return 0;
}
/**
* resize.c
*
* Computer Science 50
* Problem Set 4
*
* Resizes a 24-bit uncompressed bmp by a factor of n
*/
#include <stdio.h>
#include <stdlib.h>
#include "bmp.h"
int main(int argc, char* argv[])
{
// ensure proper usage
if (argc != 4 || atoi(argv[1]) > 100 || atoi(argv[1]) < 1)
{
printf("Usage: ./resize n infile outfile, where n is greater than 0 and less than or equal to 100\n");
return 1;
}
// remember filenames
char* infile = argv[2];
char* outfile = argv[3];
int n = atoi(argv[1]);
// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("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;
}
int inPadding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4; // Calculates input padding before rewriting header files so I can use it to scan accurately over input file
// resize BITMAPFILEHEADER
bi.biHeight = bi.biHeight * n; // Multiply the height by n
bi.biWidth = bi.biWidth * n; // Multiplies the width by n
// determine padding for scanlines
int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// Determine the SizeImage after the padding is set which requires biWidth be set; normally SizeImage would be right after width
bi.biSizeImage = bi.biWidth * abs(bi.biHeight) * sizeof(RGBTRIPLE) + padding * abs(bi.biHeight);
bf.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + bi.biSizeImage; // concentrates just on the size of the bitmap, subtracting out the headers, multiplies by n to expand number of pixels, multiples by the number of bytes per pixel (the number of bytes per pixel)
// write outfile's BITMAPFILEHEADER
fwrite(&bf, sizeof(BITMAPFILEHEADER), 1, outptr);
// write outfile's BITMAPINFOHEADER
fwrite(&bi, sizeof(BITMAPINFOHEADER), 1, outptr);
// iterate over infile's scanlines
for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
for (int m = 0; m < n; m++)
{
// iterate over pixels in scanline
for (int j = 0; j < bi.biWidth/n; j++)
{
// temporary storage
RGBTRIPLE triple;
// read RGB triple from infile
fread(&triple, sizeof(RGBTRIPLE), 1, inptr);
for (int l = 0; l < n; l++)
{
// write RGB triple to outfile
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}
fseek(inptr, inPadding, SEEK_CUR);
for (int k = 0; k < padding; k++) // Adds padding to each row
{
fputc(0x00, outptr);
}
if(m < (n-1))
{
fseek(inptr, -(bi.biWidth/n * sizeof(RGBTRIPLE) + inPadding), SEEK_CUR); // Resets the INPUT file selector location to the beginning of the row
}
}
}
// close infile
fclose(inptr);
// close outfile
fclose(outptr);
// that's all folks
return 0;
}
/**
* resize.c
*
* Computer Science 50
* Problem Set 4
*
* Resizes a 24-bit uncompressed bmp by a factor of n
*/
#include <stdio.h>
#include <stdlib.h>
#include "bmp.h"
int main(int argc, char* argv[])
{
// ensure proper usage
if (argc != 4 || atoi(argv[1]) > 100 || atoi(argv[1]) < 1)
{
printf("Usage: ./resize n infile outfile, where n is greater than 0 and less than or equal to 100\n");
return 1;
}
// remember filenames
char* infile = argv[2];
char* outfile = argv[3];
int n = atoi(argv[1]);
// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("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;
}
int inPadding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4; // Calculates input padding before rewriting header files so I can use it to scan accurately over input file
// resize BITMAPFILEHEADER
bi.biHeight = bi.biHeight * n; // Multiply the height by n
bi.biWidth = bi.biWidth * n; // Multiplies the width by n
// determine padding for scanlines
int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// Determine the SizeImage after the padding is set which requires biWidth be set; normally SizeImage would be right after width
bi.biSizeImage = bi.biWidth * abs(bi.biHeight) * sizeof(RGBTRIPLE) + padding * abs(bi.biHeight);
bf.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + bi.biSizeImage; // concentrates just on the size of the bitmap, subtracting out the headers, multiplies by n to expand number of pixels, multiples by the number of bytes per pixel (the number of bytes per pixel)
// write outfile's BITMAPFILEHEADER
fwrite(&bf, sizeof(BITMAPFILEHEADER), 1, outptr);
// write outfile's BITMAPINFOHEADER
fwrite(&bi, sizeof(BITMAPINFOHEADER), 1, outptr);
// iterate over infile's scanlines
for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
for (int m = 0; m < n; m++)
{
// iterate over pixels in scanline
for (int j = 0; j < bi.biWidth/n; j++)
{
// temporary storage
RGBTRIPLE triple;
// read RGB triple from infile
fread(&triple, sizeof(RGBTRIPLE), 1, inptr);
for (int l = 0; l < n; l++)
{
// write RGB triple to outfile
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}
fseek(inptr, inPadding, SEEK_CUR);
for (int k = 0; k < padding; k++) // Adds padding to each row
{
fputc(0x00, outptr);
}
if(m < (n-1))
{
fseek(inptr, -(bi.biWidth/n * sizeof(RGBTRIPLE) + inPadding), SEEK_CUR); // Resets the INPUT file selector location to the beginning of the row
}
}
}
// close infile
fclose(inptr);
// close outfile
fclose(outptr);
// that's all folks
return 0;
}
Resize - output files look right but check50 gives errors
I'm running resize.
The headers are right when I check them using peek.
The files look right (smiley, small, even whodunit).
But when I run check50 I get these errors:
:( resizes 1x1-pixel BMP to 2x2 correctly when n is 2
:( resizes 1x1-pixel BMP to 3x3 correctly when n is 3
:( resizes 1x1-pixel BMP to 4x4 correctly when n is 4
:( resizes 1x1-pixel BMP to 5x5 correctly when n is 5
:( resizes 2x2-pixel BMP to 4x4 correctly when n is 2
Any ideas? I notice my file sizes are larger than the staff versions.
Here is my code:
/**
* resize.c
*
* Computer Science 50
* Problem Set 4
*
* Resizes a 24-bit uncompressed bmp by a factor of n
*/
#include <stdio.h>
#include <stdlib.h>
#include "bmp.h"
int main(int argc, char* argv[])
{
// ensure proper usage
if (argc != 4 || atoi(argv[1]) > 100 || atoi(argv[1]) < 1)
{
printf("Usage: ./resize n infile outfile, where n is greater than 0 and less than or equal to 100\n");
return 1;
}
// remember filenames
char* infile = argv[2];
char* outfile = argv[3];
int n = atoi(argv[1]);
// open input file
FILE* inptr = fopen(infile, "r");
if (inptr == NULL)
{
printf("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;
}
int inPadding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4; // Calculates input padding before rewriting header files so I can use it to scan accurately over input file
// resize BITMAPFILEHEADER
bi.biHeight = bi.biHeight * n; // Multiply the height by n
bi.biWidth = bi.biWidth * n; // Multiplies the width by n
// determine padding for scanlines
int padding = (4 - (bi.biWidth * sizeof(RGBTRIPLE)) % 4) % 4;
// Determine the SizeImage after the padding is set which requires biWidth be set; normally SizeImage would be right after width
bi.biSizeImage = bi.biWidth * abs(bi.biHeight) * sizeof(RGBTRIPLE) + padding * abs(bi.biHeight);
bf.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + bi.biSizeImage; // concentrates just on the size of the bitmap, subtracting out the headers, multiplies by n to expand number of pixels, multiples by the number of bytes per pixel (the number of bytes per pixel)
// write outfile's BITMAPFILEHEADER
fwrite(&bf, sizeof(BITMAPFILEHEADER), 1, outptr);
// write outfile's BITMAPINFOHEADER
fwrite(&bi, sizeof(BITMAPINFOHEADER), 1, outptr);
// iterate over infile's scanlines
for (int i = 0, biHeight = abs(bi.biHeight); i < biHeight; i++)
{
for (int m = 0; m < n; m++)
{
// iterate over pixels in scanline
for (int j = 0; j < bi.biWidth/n; j++)
{
// temporary storage
RGBTRIPLE triple;
// read RGB triple from infile
fread(&triple, sizeof(RGBTRIPLE), 1, inptr);
for (int l = 0; l < n; l++)
{
// write RGB triple to outfile
fwrite(&triple, sizeof(RGBTRIPLE), 1, outptr);
}
}
fseek(inptr, inPadding, SEEK_CUR);
for (int k = 0; k < padding; k++) // Adds padding to each row
{
fputc(0x00, outptr);
}
if(m < (n-1))
{
fseek(inptr, -(bi.biWidth/n * sizeof(RGBTRIPLE) + inPadding), SEEK_CUR); // Resets the INPUT file selector location to the beginning of the row
}
}
}
// close infile
fclose(inptr);
// close outfile
fclose(outptr);
// that's all folks
return 0;
}
default