DCM医学影像文件的格式与读取方法分享

 

DCM医学影像文件的格式与读取方法分享

转自 http://bbs.csdn.net/topics/390146622

2014-01-10 13:25  636人阅读  评论(0)  收藏  举报

医学影像DCM是个类似PNG的分块格式，内涵丰富医疗信息，由于应用领域较窄，OpenCV没有提供对其加载支持，一般采用dcmtk库进行加载。

博主本着研究探索的精神写了这段代码，并分享出来，提供了解析DCM的DIB数据、宽高、窗宽窗位、像素间距的功能，支持反色DCM。

将来可以参考spec文档进行扩充，可以在大框架中加入块的处理，从而抽取更多感兴趣的信息，也可以加入压缩DCM的支持。

 // 输入：文件名
 // 输出：宽高 窗宽窗位 像素间距 dib
 unsigned short* dcmLoadImage(char* fn, int& width, int& height, int& windowWidth, int& windowLevel, double& pixelSpacing)
 {
     // 读取整个文件到内存
     FILE* f = fopen(fn, "rb");
     fseek(f, 0, SEEK_END);
     int dcmSize = ftell(f);
     fseek(f, 0, SEEK_SET);
     unsigned char* dcm = new unsigned char[dcmSize];
     fread(dcm, dcmSize, 1, f);
     fclose(f);

     // 解析
     width = -1;
     height = -1;
     windowWidth = -1;
     windowLevel = -1;
     pixelSpacing = 0.0;
     bool invert = false;
     unsigned short* dib = NULL;
     int dibSize = -1;
     int p = 132;
     while( p
     {
         short group = *(short*)(dcm+p);
         p+=2;
         short element = *(short*)(dcm+p);
         p+=2;
         //cout<


         if(group==0x0002)
         {
             if(element==0x0001)// 2,1
             {
                 p+=10;
             }
             else// 2,*
             {
                 char vr[3];
                 vr[0] = dcm[p++];
                 vr[1] = dcm[p++];
                 vr[2] = '\0';
                 short size = *(short*)(dcm+p);
                 p+=2;
                 p+=size;
             }
         }
         else// *
         {
             int size = *(int*)(dcm+p);
             p+=4;
             if(size==-1)
                 size=0;
             if(group==0x0028&&element==0x0010)
                 height = *(short*)(dcm+p);
             if(group==0x0028&&element==0x0030)
                 pixelSpacing = atof((char*)dcm+p);
             if(group==0x0028&&element==0x0004)
                 invert = !strncmp((char*)dcm+p, "MONOCHROME1", 11);
             else if(group==0x0028&&element==0x0011)
                 width = *(short*)(dcm+p);
             else if(group==0x0028&&element==0x1050)
                 windowLevel = atoi((char*)dcm+p);
             else if(group==0x0028&&element==0x1051)
                 windowWidth = atoi((char*)dcm+p);
             else if(group==0x7FE0&&element==0x0010)
             {
                 dibSize = size;
                 dib = new unsigned short[dibSize];
                 memcpy(dib, dcm+p, dibSize);
             }
             p+=size;
         }
     }
     assert(p==dcmSize);
     assert(width!=-1);
     assert(height!=-1);
     assert(windowLevel!=-1);
     assert(windowWidth!=-1);
     assert(dib!=NULL);
     assert(dibSize==width*height*2);

     // 反图做修正
     if(invert)
     {
         for(int i=0; i
             dib[i] ^= 0xFFFF;
         windowLevel = 65535-windowLevel;
     }

     delete[] dcm;
     return dib;
 }


 void dcmReleaseImage(unsigned short* dib)
 {
     delete[] dib;
 }