Getting an image from its URL

I am using visual c++. I have the URL and the size of an image and i want to manipulate it. how can i get the image

Is there a variable in c++ specific for images? If it's possible some code samples would be very helpful! this is my code for more details:

string Excella::AfficherImage(char *Device, unsigned int nIndex, char *DocInfo)
    {
        char cValue1[512] = "";
        char cValue2[512] = "";
        DWORD nValueSize;
        nValueSize = 512;
        // Get the image size from DocInfo
        // cValue1 contains the image size
        MTMICRGetIndexValue(DocInfo, "ImageInfo", "ImageSize", nIndex, cValue1, &nValueSize);
        // Get the image URL from DocInfo
        // cValue2 contains the image URL
        MTMICRGetIndexValue(DocInfo, "ImageInfo", "ImageURL", nIndex, cValue2, &nValueSize);


     // Image treatment
    }

I also need to know how i can convert a char* to an image?! thanks for ur help!!!!!!!!!!!!