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.txt RGB array to BMP FAULTY OUTPUT

Jun 25, 2015 at 12:32am
dangerzone37 (4)
Hi everyone,


My purpose;

RGB values at txt,To convert a file in BMP format.


Bmp to blabla.txt


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#include <iostream>
#include <string>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include "bitmap_image.hpp"

using namespace std;

int main () {
    FILE *streamIn;

    streamIn = fopen("./Lenna.bmp", "r");
    if (streamIn == (FILE *)0) {
        printf("File opening error ocurred. Exiting program.\n");
        return 0;
    }

    unsigned char info[54];
    fread(info, sizeof(unsigned char), 54, streamIn);

    unsigned int width1 = *(int*)&info[18];
    unsigned int height1 = *(int*)&info[22];

    unsigned char image11[width1*height1][3];
    unsigned int i = 0;
    FILE *fw;
    fw = fopen("blabla.txt","w");

    for(i=0;i<width1*height1;i++) {
        image11[i][2] = getc(streamIn);
        image11[i][1] = getc(streamIn);
        image11[i][0] = getc(streamIn);
        //printf("pixel %d : [%d,%d,%d]\n",i+1,image11[i][0],image11[i][1],image11[i][2]);
        fprintf(fw,"%d %d %d\n",image11[i][0],image11[i][1],image11[i][2]);

    }
/*
    fclose(streamIn);
    bitmap_image image(512,512);
               image_drawer draw(image);
				int k = 0;
                for (unsigned int d = 0; d < image.width(); ++d)
               {
                  for (unsigned int m = 0; m < image.height(); ++m)
                  {
                  		image.set_pixel(d,m,image11[k][0],image11[k][1],image11[k][2]);
                    k++;

                  }
               }

               image.save_image("test18_color_maps.bmp");
*/

    return 0;
}
Edit & run on cpp.sh


My blabla.txt;

82 22 57
82 22 57
96 32 62
93 28 62
97 30 65
94 21 57
92 26 62
93 28 60
98 36 68
94 27 66
89 21 58
93 25 66
95 27 75
...

.txt to BMP
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#include <iostream>
#include <string>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string.h>
#include "bitmap_image.hpp"

using namespace std;
int next;

void numberlines(){
    ifstream openFile("blabla.txt");
    string line;

    while (getline(openFile, line)) {
    if (line.empty()) continue;

    istringstream iss(line);

    next = 1+next;

  }
  cout<<next<<endl;
}

int main () {
    FILE *streamIn;
    numberlines();  
    streamIn = fopen("./blabla.txt", "r");
    if (streamIn == (FILE *)0) {
        printf("File opening error ocurred. Exiting program.\n");
        return 0;
    }

    //unsigned char info[54];
    //fread(info, sizeof(unsigned char), 54, streamIn);

    unsigned char image11[next][3];
    unsigned int i = 0;
    for(i=0;i<next;i++) {
        image11[i][0] = getc(streamIn);
        image11[i][1] = getc(streamIn);
        image11[i][2] = getc(streamIn);
        printf("pixel %d : [%d,%d,%d]\n",i+1,image11[i][0],image11[i][1],image11[i][2]);    //FAULTY OUTPUT
    }


fclose(streamIn);
    bitmap_image image(512,512);
               image_drawer draw(image);
				int k = 0;
                for (unsigned int d = 0; d < image.width(); ++d)
               {
                  for (unsigned int m = 0; m < image.height(); ++m)
                  {
                  		image.set_pixel(d,m,image11[k][0],image11[k][1],image11[k][2]);
                    k++;

                  }
               }
  cout<<next<<endl;
               image.save_image("test18_color_maps.bmp");


    return 0;
}
Edit & run on cpp.sh


FAULTY OUTPUT

My blabla.txt
Line 1 = 82 22 57
txt to BMP
Line 1 = 56 50 32

İf;

unsigned char info[54];
fread(info, sizeof(unsigned char), 54, streamIn);
Line 1 = 57 50 32

54 instead of 12
Line 1 = 50 50 32

...

Why is this happening ?
Last edited on Jun 25, 2015 at 12:43am
Jun 25, 2015 at 8:00am
coder777 (8449)
getc(streamIn); gets a single character like '8'. The ascii code for '8' is 56. See:

http://www.asciitable.com/


What you need is fscanf. See:

http://www.cplusplus.com/reference/cstdio/fscanf/?kw=fscanf
Jun 25, 2015 at 1:26pm
dangerzone37 (4)
Hmm I got, but;

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unsigned char info [54];
....
...

image11[i][0] = fscanf (streamIn, "%s", info);
image11[i][1] = fscanf (streamIn, "%s", info);
image11[i][2] = fscanf (streamIn, "%s", info);


Line 1 = 1 1 1
Line 2 = 1 1 1
Line 3 = 1 1 1
....

Values do not get again ?
Jun 25, 2015 at 3:18pm
ne555 (10692)
man fscanf wrote:
RETURN VALUE
These functions return the number of input items successfully matched and assigned, which can be fewer
than provided for, or even zero in the event of an early matching failure.

Jun 25, 2015 at 10:03pm
dangerzone37 (4)
I understand exactly what you mean,

How do I need to change the code ?

getline() it works but when writing a bitmap, unsigned char I have to do the conversion.

How can I solve this problem?
Jun 26, 2015 at 6:07am
coder777 (8449)
Well, fscanf works similar to printf, hence use it similar:
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if(fscanf (streamIn, "%d %d %d", &image11[i][0], &image11[i][1], &image11[i][2]) != 3)
  ... // End of file or error -> break;
Jun 26, 2015 at 9:51am
dhayden (5799)
But image11 is an array of unsigned chars, not integers. I think you want:
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int r, g, b, i;
for (i=0; fscanf (streamIn, "%d %d %d", &r, &g, &b) == 3; ++i) {
    image11[i][0] = r;
    image11[i][1] = g;
    image11[i][2] = b;
}


This has the advantage of counting the lines (or entries anyway) for you too.
Jun 26, 2015 at 11:10am
dangerzone37 (4)
It is OK

Thanks to everyone who helped
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