算法ByteRun，解压缩出错，.bmp

Question

我对算法ByteRun有一点问题（非常类似于RLE）。好吧，当我使解压缩smth出错并且我的输出与输入不同时。原始cookie以.bmp格式（24像素）保存。输出应该是我们的格式，例如。 “.xd”。

我看到（目前为止）只有4个选项，它取决于我们在宽度上有多少像素。

我们有421

对于422我们有

我们有423

我们有424

和原文：

Tbh我认为我考虑填充但是idk是什么让我的可怜的饼干破了。 :(请帮我保存饼干。：D

#include <iostream>
#include <stdlib.h>
#include <fstream>
using namespace std;

struct colour                               // structure of every pixel BGR
{
    unsigned char   b;
    unsigned char   g;
    unsigned char   r;
};

unsigned int reading_and_writing_the_header(FILE *file_in, FILE *file_out, unsigned char header[])
{

unsigned int width = 0;
unsigned int height = 0;
unsigned int bite_for_pixel = 0;
unsigned int amount_of_pixels = 0;
unsigned int padding = 0;
unsigned int row = 0;

fread(header, 1, 54, file_in);                      // reading the header  // 1=sizeof(unsigned int) = sizof(uni8_t)
fwrite(header, 1, 54, file_out);                    // wrting header


width = *(unsigned int*)&header[18];
height = *(unsigned int*)&header[22];
bite_for_pixel = *(unsigned int*)&header[28];

padding = width % 4;                                    // counting padding
row = width * 3 + padding;                              // bites in a row
amount_of_pixels = height * row;                        // amount of bites after header
return amount_of_pixels;
}

void compression_ByteRun(FILE *file_in,FILE *file_out, unsigned int aop)
{
colour *q = new colour[aop];

fread(q, 1, aop, file_in);
int k = 0;
colour x, y;
int counter1 = 0;
int counter2 = 0;
char *the_same_colours = new char[4];
char *diffrent_colours = new char[128 * 3 + 1];

while (k < (aop / 3))
{
    x = q[k];
    y = q[k + 1];
    if (x.r == y.r && x.b == y.b && x.g == y.g)         //if the same R and B and G                                                     
    {
        if (counter1 == 126)                          // not sure about what exactly should be here 
        {
            the_same_colours[0] = (counter1)*(-1);
            fwrite(the_same_colours, 1, 4, file_out);
            counter1 = 0;
        }
        if (counter2 != 0)
        {
            diffrent_colours[0] = counter2 / 3 - 1;
            fwrite(diffrent_colours, 1, counter2 + 1, file_out);
            counter2 = 0;
        }

        counter1++;
        k++;
        continue;
    }
    else                                        // if we have diffrent colours side by side
    {
        if (counter1 != 0)
        {
            the_same_colours[0] = (counter1)*(-1);
            the_same_colours[1] = x.b;
            the_same_colours[2] = x.g;
            the_same_colours[3] = x.r;
            fwrite(the_same_colours, 1, 4, file_out);
            counter1 = 0;
            k++;
        }
        else
        {
            diffrent_colours[counter2 + 1] = x.b;
            diffrent_colours[counter2 + 2] = x.g;
            diffrent_colours[counter2 + 3] = x.r;
            counter2 = counter2+ 3;


            if (counter2 / 3 == 127)                    // same here, not sure about what exactly should be here 
            {
                diffrent_colours[0] = counter2 / 3 - 1;
                fwrite(diffrent_colours, 1, counter2 + 1, file_out);
                counter2 = 0;
            }
            k++;
        }
    }
}
}

void decompression_ByteRun(FILE *file_in,FILE *file_out)
{
char x;                                 // variavle where we keep how many colours we need 2 write 
char y, z, o;                           // variables for comparing values
bool  game_over;                        // variable for checking if the file isn't over 


game_over = fread(&x, 1, 1, file_in);                                                   
while (game_over == true)
{
    if (x >= 0)                         // if we had diffrent colours side by dide
    {
        for (int i = 1; i <= x * 3 + 3; i++)
        {
            fread(&y, 1, 1, file_in);
            fwrite(&y, 1, 1, file_out);
        }
        game_over = fread(&x, 1, 1, file_in);
        continue;
    }

    else                                // if we have the same colours
    {
        fread(&z, 1, 1, file_in);
        fread(&o, 1, 1, file_in);
        fread(&y, 1, 1, file_in);
        for (int i = 1; i <= (-(x)+1); i++)
        {
            fwrite(&z, 1, 1, file_out);
            fwrite(&o, 1, 1, file_out);
            fwrite(&y, 1, 1, file_out);
        }
        game_over = fread(&x, 1, 1, file_in);
    }
}
}

int main()
{
FILE *file_in;
FILE *file_out;
int number = 0;
char* name = new char;
char* name_out = new char;
unsigned char header[54];
unsigned int amount_of_pixels = 0;

cout << "Write input file: " << endl;
cin >> name;
cout << endl;

cout << "Write output file:" << endl;
cin >> name_out;
cout << endl;

cout << "What u wanna do (1- compression or 2- decompression ";
cin >> number;

file_in = fopen(name, "rb");
if (file_in == NULL)
{
    cout << "Error we couldn't open that file.\n Contact our IT group 4 more help" << endl;
    system("PAUSE");
    exit(0);
}

file_out = fopen(name_out, "wb");
if (file_out == NULL)
{
    cout << "Error we couldn't open that file.\n Contact our IT group 4 more help" << endl;
    system("PAUSE");
    exit(0);
}

switch (number)
{
case 1:
    cout << "Compression Byterun" << endl;
    amount_of_pixels = reading_and_writing_the_header(file_in, file_out, header);
    compression_ByteRun(file_in, file_out, amount_of_pixels);
    break;
case 2:
    cout << "Decompression Byterun" << endl;
    amount_of_pixels = reading_and_writing_the_header(file_in, file_out, header);
    decompression_ByteRun(file_in, file_out);
    break;
}
system("PAUSE");
return 0;
}