keypoints点数太多，编译的时候出错

[cugcsu]

`{
vectorcv::KeyPoint tmvKeys;
size_t kpn;
ifkfKeys.read(reinterpret_cast<char*>(hd),2);
if(hd[0]!=0xeb || hd[1]!=0x90)
cerr<<"header error kfKeyPoints, shouldn't"<<endl;

            ifkfKeys.read(reinterpret_cast<char*>(&kpn), sizeof(size_t));
            tmvKeys.resize(kpn);
            //for(size_t vit=0;vit<kpn;vit++)
            for(vector<cv::KeyPoint>::iterator vitkeys=tmvKeys.begin(), vendkeys=tmvKeys.end(); vitkeys!=vendkeys; vitkeys++)
            {
                float ptx,pty,size,angle,response;
                int octave,classid;
                ifkfKeys.read(reinterpret_cast<char*>(&ptx), sizeof(float));
                ifkfKeys.read(reinterpret_cast<char*>(&pty), sizeof(float));
                ifkfKeys.read(reinterpret_cast<char*>(&size), sizeof(float));
                ifkfKeys.read(reinterpret_cast<char*>(&angle), sizeof(float));
                ifkfKeys.read(reinterpret_cast<char*>(&response), sizeof(float));
                ifkfKeys.read(reinterpret_cast<char*>(&octave), sizeof(int));
                ifkfKeys.read(reinterpret_cast<char*>(&classid), sizeof(int));
                //tmvKeys[vit] = cv::KeyPoint(ptx,pty,size,angle,response,octave,classid);
                *vitkeys = cv::KeyPoint(ptx,pty,size,angle,response,octave,classid);
                if(ifkfKeys.fail())  cerr<<"loopcnt: "<<skfcnt<<" mnId "<<mnId<<" ifkfKeys fail. shouldn't"<<endl;
            }
            tmpKF->SetKeyPoints(tmvKeys);
        }`

kpn的数值超过几百亿