別のサイトで同じような質問をさせて頂きました。

処理の流れとしてはカメラで撮ったcv::Matをunsined char化し、stringの動的配列として共有メモリに格納し、子プロセスでstringをイテレータで順次，unsigned char化してcv::Matに戻して再生したいです。

しかし、問題があり、

vcap >> mat;

MatToBytes(mat, &pBuf );
std::string sName;
myshmvector->push_back(sName(pBuf));、

というコードで、MatToBytesにMatと pBufというunsigned charの二重ポインタを引数でとり、格納し、memcpyしたいのですが、
共有メモリのVectorにてStringで格納する際、
コンパイルエラーでno match for call to ‘(std::string {aka std::basic_string}) (uchar*&)’
myshmvector->push_back(sName(pBuf));

pBufのucharがbasic_stringにどうしても合わないようです。

子プロセスのイテレータのも問題があるようで

  MyShmStringVector::iterator it;
  cv::Mat mat;
  cv::VideoCapture vcap(0);
  uchar* pBuf = NULL;

  for(it = myvector->begin(); it !=myvector->end(); ++it){
        pBuf = (unsigned char*)(*it).c_str();
        std::memcpy(mat, pBuf, it->size());
        cv::imshow("window1", mat);
  }

エラーでは

cv::Mat’ to ‘void*’ for argument ‘1’ to ‘void* memcpy(void*, const void*, size_t)’
    std::memcpy(mat, pBuf, it->size());

が出力されます。
ご教授の方お願いします。

全体のコードになります。（解りずらいと思いますが、説明下手と状況把握が不十分なので）

#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/string.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <string>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <cstdlib> // std::system

using namespace boost::interprocess;

typedef unsigned char uchar;

typedef allocator<char, managed_shared_memory::segment_manager> CharAllocator;

typedef basic_string<char, std::char_traits<char>, CharAllocator> MyShmString;

typedef allocator<MyShmString, managed_shared_memory::segment_manager> StringAllocator;

typedef vector<MyShmString, StringAllocator> MyShmStringVector;

int MatToBytes(cv::Mat image, uchar ** pimage_uchar)
{
    uchar * image_uchar = * pimage_uchar;
    // class data members of ints
    int image_rows = image.rows;
    int image_cols = image.cols;
    int image_type = image.type();

    int image_size = image.total() * image.elemSize();
    image_uchar = new uchar[image_size];
    std::memcpy(image_uchar, image.data, image_size * sizeof(uchar));
    return 1;
}

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

    struct shm_remove
    {
        shm_remove(){shared_memory_object::remove("MySharedMemory");}
        ~shm_remove(){shared_memory_object::remove("MySharedMemory");}
    }remover;


    if(argc == 1){ //Parent process
        // Remove shared memory on construction and destruction

    // Create a new segment with given name and size
    managed_shared_memory segment(create_only,"MySharedMemory",65536);

    //Initialize shared memory STL-compatible allocator
    CharAllocator charallocator(segment.get_segment_manager());
    StringAllocator stringallocator(segment.get_segment_manager());
    //Construct a vector named "MyVector" in shared memory with argument alloc_inst
    MyShmStringVector *myshmvector = segment.construct<MyShmStringVector>("MyVector")(stringallocator);


    cv::Mat InputImage;
    cv::Mat mat;
    cv::VideoCapture vcap(0);
    uchar* pBuf = NULL;


    if (!vcap.isOpened())
        return -1;

    while (1) {
        vcap >> mat;

        MatToBytes(mat, &pBuf );
        std::string sName;
        myshmvector->push_back(sName(pBuf));
        //Launch child process
        if(cv::waitKey(30) >= 0) break;
    }
    // Launch child process
    std::string s(argv[0]); s += " child";
    if(0 != std::system(s.c_str()))
        return 1;

    // check child has destroyed the vector
    if(segment.find<MyShmStringVector>("MyVector").first)
        return 1;
    }
    else{// child process
        // Open the managed segment
        managed_shared_memory segment(open_only, "MySharedMemory");

        // Find the vector using c-string name
        MyShmStringVector *myvector = segment.find<MyShmStringVector>("MyVector").first;

        // Use vector in reverse order

        MyShmStringVector::iterator it;
        cv::Mat mat;
        cv::VideoCapture vcap(0);
        uchar* pBuf = NULL;

        for(it = myvector->begin(); it !=myvector->end(); ++it){
            pBuf = (unsigned char*)(*it).c_str();
            std::memcpy(mat, pBuf, it->size());
            cv::imshow("window1", mat);
        }

        segment.destroy<MyShmStringVector>("MyVector");

    }
    return 0;
}