c++ - 将类似值 bmp 计数为像素值 C++

Question

我拍摄了一张位图图像，并从中提取了指定像素行的 R、G、B 整数。将 int 转换为字符串，以便我可以打印 6 种特定颜色。我不知道如何用 int 来做。

问题我能够将第 0-184 行(对应于该行中的像素)打印为顺序数据 1234... 或红色、红色、红色、黑色、黑色、灰色....

但是我需要计算相似/相同的颜色，显示相似颜色的总和，并重置计数器直到该颜色再次出现，然后重新计数。我认为 if 或 if else 会做，但不完全是。可能是我的代码结构导致了问题？

所以我想要的是:

5   red,
10  black,
2   red,
1   gray,

等等……

这是我的代码，我是初学者所以批评我缺乏知识，以便我可以正确学习。

#include <iostream>
#include <sstream>
#include <string>
#include "EasyBMP.h"
#include "EasyBMP_BMP.h"
#include "EasyBMP_DataStructures.h"
#include "EasyBMP_VariousBMPutilities.h"

//Conversion and comparison function
void calculate(int i, int x, int p);

int main(int argc, const char * argv[])
{

BMP Image;
Image.ReadFromFile( "BMP GOES HERE 24bit" );

std::cout << "Image Height and Width: " << Image.TellHeight() << " x " << Image.TellWidth() << std::endl;

std::cout << "Enter your row: ";

int pixX = 0;
std::cin >> pixX;

//Set getpixel to top of row
int pixY  = 0;

for( pixY = 0; pixY < Image.TellHeight() ; pixY++ )
{
    std::cout << "Pixel: " << pixY + 1;

    RGBApixel Temp = Image.GetPixel(pixX,pixY);

    //Array to store pixel color ints
    int pixy[3];
    pixy[0] = Temp.Red;
    pixy[1] = Temp.Green;
    pixy[2] = Temp.Blue;

    calculate(pixy[0], pixy[1], pixy[2]);
}

return 0;
}


void calculate(int rnum, int gnum, int bnum)
{

//String which will contain the result
std::string result;

//Stream used for the conversion
std::ostringstream convert;

//Insert the textual representation of 'Number' in the characters in the stream
convert << rnum;                

convert << gnum;

convert << bnum;

// set 'Result' to the contents of the stream
result = convert.str();    

// compare result to my given value
if (result == "25500")
{
    std::cout << " RED  " << std::endl;
}
if (result == "255255255")
{
    std::cout << " WHITE " << std::endl;
}
if (result == "000")
{
    std::cout << " BLACK" << std::endl;
}
if (result == "148148148")
{
    std::cout << " GRAY " << std::endl;
}
if (result == "267326")
{
    std::cout << " GREEN " << std::endl;
}
if (result == "2551260")
{
    std::cout << " ORANGE " << std::endl;
}
}

以下是工作代码。请注意，如果您使用它，我的图像只有 6 种特定颜色。要更改打印输出，必须根据需要修改 switch 语句的大小写。

#include <iostream>
#include <vector>
#include "EasyBMP.h"    
#include "EasyBMP_BMP.h"
#include "EasyBMP_DataStructures.h"
#include "EasyBMP_VariousBMPutilities.h"

long toRGB(long red, long grn, long blu);


int main(int argc, const char * argv[])
{

BMP Image;
Image.ReadFromFile( "Your BMP HERE" );

std::cout << "Image Height and Width: " << Image.TellHeight() << " x " << Image.TellWidth() << std::endl;

std::cout << "Enter your row: ";

int pixX = 0;
std::cin >> pixX;
if (pixX != 0)                              //Subtract one from input if not 0, image starts at 0,0
{
    pixX -= 1;
}

long pop  = 0;
long pop1 = 0;

RGBApixel current = Image.GetPixel(pixX,0);

long pixy1[3];                                        //Array to store pixel color ints
pixy1[0] = current.Red;
pixy1[1] = current.Green;
pixy1[2] = current.Blue;

pop1 = toRGB(pixy1[0], pixy1[1], pixy1[2]);


int count = 0;
for( int pixY = 0; pixY < Image.TellHeight() ; pixY++ )
{
    RGBApixel Temp = Image.GetPixel(pixX,pixY);

    long pixy[3];                                        //Array to store pixel color ints
    pixy[0] = Temp.Red;
    pixy[1] = Temp.Green;
    pixy[2] = Temp.Blue;

    pop = toRGB(pixy[0], pixy[1], pixy[2]);

    if (pop == pop1)
    {
        count++;
    }
    else
    {
        switch (pop1) {
            case 0:
                std::cout << "(" << count << ")\t" << "BLACK\n" << std::endl;
                break;
            case 16711680:
                std::cout << "(" << count << ")\t" << "RED\n" << std::endl;
                break;
            case 9737364:
                std::cout << "(" << count << ")\t" << "GRAY\n" << std::endl;
                break;
            case 16777215:
                std::cout << "(" << count << ")\t" << "WHITE\n" << std::endl;
                break;
            case 1722650:
                std::cout << "(" << count << ")\t" << "GREEN\n" << std::endl;
                break;
            case 16743936:
                std::cout << "(" << count << ")\t" << "ORANGE\n" << std::endl;
                break;
            default:
                std::cout << " !!!NO Specified COLOR For!!! " << pop1 << std::endl;
                break;
        }

        pop1 = pop;                                     //Reset the count and current     color
        count = 1;
    }
}
    if (count > 0)                                      //Returns last color and count
    {
        switch (pop1) {
            case 0:
                std::cout << "(" << count << ")\t" << "BLACK\n" << std::endl;
                break;
            case 16711680:
                std::cout << "(" << count << ")\t" << "RED\n" << std::endl;
                break;
            case 9737364:
                std::cout << "(" << count << ")\t" << "GRAY\n" << std::endl;
                break;
            case 16777215:
                std::cout << "(" << count << ")\t" << "WHITE\n" << std::endl;
                break;
            case 1722650:
                std::cout << "(" << count << ")\t" << "GREEN\n" << std::endl;
                break;
            case 16743936:
                std::cout << "(" << count << ")\t" << "ORANGE\n" << std::endl;
                break;
            default:
                std::cout << " !!!NO Specified COLOR For!!! " << pop1 << std::endl;
                break;
    }
}

return 0;
}

long toRGB(long a, long b, long c)                          //Function to convert R, G, B      values to unique value
{
long color = 0;
color |= (a & 255) << 16;
color |= (b & 255) << 8;
color |= (c & 255);

return color;
}

Answer 1

我之前并没有真正理解你的问题，所以我写了一个更适合你的问题的新答案。

我想你可以用这样的东西(修改你的代码)得到你想要的东西:

RGBApixel current = Image.GetPixel(pixX,0);
int count = 0;
for( pixY = 0; pixY < Image.TellHeight() ; pixY++ )
{
    RGBApixel Temp = Image.GetPixel(pixX,pixY);
    if (Temp == current)
    {
         count++;
    }
    else
    {
         // same-color sequence ended
         // Add code here to print out current color and count
         --- your output code ----

         // now reset the count and current color
         current = Temp;
         count = 1;
    }
}

// Now just print out the last sequence
if (count > 0)
{
    --- your output code here again ---
}      

我不确定的一件事是，如果有的话，== 运算符是如何为 RGBApixel 定义的。如果它没有定义或者似乎没有根据它们的颜色等同像素，只需编写一个像 pixelsAreEqual(RBGAPIxel p1, RGBApixel p2) 这样的函数，它需要两个像素，如果它们有相同的 RGB 值。