基础图像处理---图像读写/保存与基础图像绘制框架(纯C代码，不依赖任何第三方库)

对于初学者要入门图像处理这一行，想必大家都遇到这样的问题：

1，单纯用C/C++语言进行图像处理，苦于各种图像读写保存的库的加载调用，或者说实在不想用MFC，不想用CImage等，但是又没有办法；

2，想用高级语言，比如C#/JAVA等，因为他们有强大的图像加载保存API，可以直接方便的调用，但是，算法处理还是C/C++为主，毕竟用C#/JAVA做图像处理项目的太少太少；

3，如果想要自己实现图像的读写/保存算法，没有一定的功底，几乎不太可能，严重阻碍了初学者学习的热情；

对于一个初学者，或者小白来说，要搞清楚这些东西，简直如同噩梦，针对这些问题，本文给出C语言实现的一个更适合初学者入门的基础图像处理框架：

①，BMP/JPG/PNG/TGA格式图像读写/保存代码；

②，点/线/圆/三角形/长方形/多边形等常用形状的绘制代码；

上述两点，均由C语言实现，不依赖任何第三方库，极大的方便了大家学习使用；

1，BMP/JPG/PNG/TGA格式图像读写

这部分代码来自于github上的开源代码：https://github.com/XiuSdk/stb

stb代码框架中包含了各种图像读写操作，所有代码基于C语言实现，不依赖任何第三方，这里，我进行了简单的封装，接口如下：

/************************************************************
*Function:  f_SF_ImgBase_ImageLoad
*Description: Image loading
*Params:    fileName-image file path,eg:"C:\\test.jpg".
*           width-image width.
*           height-image height.
*           component-the bits per pixel.
*                     1           grey
*                     2           grey, alpha
*                     3           red, green, blue
*                     4           red, green, blue, alpha
*Return:    image data.
************************************************************/
	unsigned char* f_SF_ImgBase_ImageLoad(char* fileName, int* width, int* height, int* component);
/************************************************************
*Function:  f_SF_ImgBase_ImageSave
*Description: Image loading
*Params:    fileName-image file path,eg:"C:\\save.jpg".
*           width-image width.
*           height-image height.
*           data-the result image data to save, with format BGRA32.
*           format-image format,0-BMP,1-JPG,2-PNG,3-TGA
*Return:    0-OK.
************************************************************/
	int f_SF_ImgBase_ImageSave(char const *fileName, int width, int height, const void* data, int format);

简单的两个接口，调用也非常简单，这两个接口，图像buffer都是bgra32格式，调用如下：

char* srcPath = "Test\\test.jpg";
	char* savePath = "Result\\res.jpg";
	int width = 0, height = 0, stride = 0, component = 0, mWidth = 0, mHeight = 0, mStride = 0, mComponent = 0;
	unsigned char* srcData = f_SF_ImgBase_ImageLoad(srcPath, &width, &height, &component);
	stride = width * 4;
    //srcData为bgra32数据
	f_SF_ImgBase_ImageSave(savePath, width, height, srcData, 1);

有了这两个接口，初学者再也不用接入什么MFC/CImage/LIBJPG/LIBPNG等复杂的东西了！

2，图像基础绘制

有了图像读写，我们在实际应用中，往往需要在图像中绘制一些标签，比如人脸检测的人脸框，绘制一个三角形，矩形，圆形，或者更复杂的绘制任意一个多边形等等，这些东西，以往我们都是使用opencv或者使用上层语言的GDI+绘制来实现的，但是，这里，本人用C语言实现了这些功能，一共350行代码，包含如下功能：

①绘制实心点和空心点

②绘制线段，允许设置线的宽度

③绘制三角形/矩形/多边形/圆形/椭圆，允许设置画笔宽度

④填充三角形/矩形/多边形/圆形/椭圆

功能接口以输入bgra32格式为主，接口如下：

/********************************************************************
*Function: ImgDrawPoints
*Description: Draw points using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          points-points array,eg:[x0,y0,x1,y1...].
*          pointNum-number of points.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          radius-size of point.
********************************************************************/
void ImgDrawPoints(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int points[], int pointNum, int r, int g, int b, int radius);

/********************************************************************
*Function: ImgDrawHollowPoints
*Description: Draw hollow points using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          points-points array,eg:[x0,y0,x1,y1...].
*          pointNum-number of points.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of pen color.
*          radius-size of point.
********************************************************************/
void ImgDrawHollowPoints(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int points[], int pointNum, int r, int g, int b, int penSize, int radius);
/********************************************************************
*Function: ImgDrawLine
*Description: Draw line using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          x1-x position of start point.
*          y1-y position of start point.
*          x2-x position of end point.
*          y2-y position of end point.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of line.
********************************************************************/
void ImgDrawLine(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride,int x1, int y1, int x2, int y2, int r, int g, int b, int penSize);
//draw rectangle
/********************************************************************
*Function: ImgDrawRectangle
*Description: Draw rectangles using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          x-x position of start point.
*          y-y position of start point.
*          w-width of rectangle.
*          h-height of rectangle.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of lines.
********************************************************************/
void ImgDrawRectangle(unsigned char*srcData, int srcWidth, int srcHeight, int srcStride, int x, int y, int w, int h, int r, int g, int b, int penSize);
/********************************************************************
*Function: ImgDrawTriangle
*Description: Draw triangles using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          x-x position of frist point.
*          y-y position of frist point.
*          x1-x position of second point.
*          y1-y position of second point.
*          x2-x position of third point.
*          y2-y position of third point.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of lines.
********************************************************************/
void ImgDrawTriangle(unsigned char*srcData, int srcWidth, int srcHeight, int srcStride, int x, int y, int x1, int y1, int x2, int y2, int r, int g, int b, int penSize);

/********************************************************************
*Function: ImgDrawCircle
*Description: Draw circle using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          centerX-x position of center point.
*          centerY-y position of center point.
*          radius-radius of circle.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of pen color.
********************************************************************/
void ImgDrawCircle(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int centerX, int centerY, int radius, int r, int g, int b, int penSize);
/********************************************************************
*Function: ImgDrawFillCircle
*Description: Fill circle using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          centerX-x position of center point.
*          centerY-y position of center point.
*          radius-radius of circle.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawFillCircle(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int centerX, int centerY, int radius, int r, int g, int b);
/********************************************************************
*Function: ImgDrawFillTriangle
*Description: Fill triangles using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          x-x position of frist point.
*          y-y position of frist point.
*          w-width of rectangle.
*          h-height of rectangle.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawFillRectangle(unsigned char*srcData, int srcWidth, int srcHeight, int srcStride, int x, int y, int w, int h, int r, int g, int b);
/********************************************************************
*Function: ImgDrawFillTriangle
*Description: Fill triangles using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          x-x position of frist point.
*          y-y position of frist point.
*          x1-x position of second point.
*          y1-y position of second point.
*          x2-x position of third point.
*          y2-y position of third point.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawFillTriangle(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int x, int y, int x1, int y1, int x2, int y2, int r, int g, int b);
/********************************************************************
*Function: ImgDrawPolygon
*Description: Draw Polygon using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          polygonPoints-points array of polygon, eg:[x0, y0, x1, y1,...].
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
*          penSize-size of pen color.
********************************************************************/
void ImgDrawPolygon(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int polygonPoints[], int pointNum, int r, int g, int b, int penSize);
/********************************************************************
*Function: ImgDrawFillPolygon
*Description: Fill Polygon using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          polygonPoints-points array of polygon, eg:[x0, y0, x1, y1,...].
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawFillPolygon(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int polygonPoints[], int pointNum, int r, int g, int b);
/********************************************************************
*Function: ImgDrawEllipse
*Description: Draw Ellipse using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          centerX-center x of eclipse.
*          centerY-center y of eclipse.
*          A-A of eclipse(A > B).
*          B-B of eclipse(B < A).
*          penSize-size of pen color.
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawEllipse(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int centerX, int centerY,  int A, int B, int r, int g, int b, int penSize);
/********************************************************************
*Function: ImgDrawFillEclipse
*Description: Fill Ellipse using specified color.
*Params:  
*          srcData-source image with bgra32 pixelformat.
*          srcWidth-width of source image.
*          srcHeight-height of source image.
*          srcStride-stride of source image.
*          centerX-center x of eclipse.
*          centerY-center y of eclipse.
*          A-A of eclipse(A > B).
*          B-B of eclipse(B < A).
*          r-Red component of pen color.
*          g-Green component of pen color.
*          b-Blue component of pen color.
********************************************************************/
void ImgDrawFillEllipse(unsigned char* srcData, int srcWidth, int srcHeight, int srcStride, int centerX, int centerY, int A, int B, int r, int g, int b);

调用举例如下：

	//Drawing Rectangle
	int x = 100, y = 100, w = 50, h = 50;
	ImgDrawRectangle(srcData, width, height, stride, x, y, w, h, penColorR, penColorG, penColorB, 3);
	//Drawing Triangle
	ImgDrawTriangle(srcData, width, height, stride, x, y, x + 100, y, x, y + 100, penColorG, penColorR, penColorB, 1);
	//fill rectangle
	ImgDrawFillRectangle(srcData, width, height, stride, 100, 300, w, h, penColorR, penColorG, penColorB);
	//fill triangle
	ImgDrawFillTriangle(srcData, width, height, stride, x, y + 100, x + 100, y + 100, x, y + 200, penColorG, penColorR, penColorB);
	int polyPoints[8] = {200, 200, 250, 130, 280, 220, 230, 300};
	//draw polygon
	ImgDrawPolygon(srcData, width, height, stride, polyPoints, 4, 200, 100, 50, 2);
	int polyPoints1[8] = {300, 400, 350, 130, 480, 220, 330, 400};
	//fill polygon
	ImgDrawFillPolygon(srcData, width, height, stride, polyPoints1, 4, 200, 100, 250);
	//fill ellipse
	ImgDrawFillEllipse(srcData, width, height, stride, 500, 500, 100, 50, 155, 245,67);
	//draw ellipse
	ImgDrawEllipse(srcData, width, height, stride, 200, 500, 100, 50, 255, 45,67, 1);

对应效果图如下：

整体算法编译DLL不足100K，可谓轻量级的库。

在使用时，只需要把库ImageProcessBasicFramework.dll和ImageProcessBasicFramework.lib以及头文件ImgBasic文件夹放到工程路径下，点击工程属性，配置link-input与VC++目录即可，如下所示：

最后，给出代码库及DEMO下载链接：https://download.csdn.net/download/trent1985/11218979

代码库为VS2010 编译，DEMO为VS2010工程。