C++ base64 opencv Mat 转换

static std::string base64Decode(const char* Data, int DataByte) { //解码表 const char DecodeTable[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, // '+' 0, 0, 0, 63, // '/' 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // '0'-'9' 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // 'A'-'Z' 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // 'a'-'z' }; std::string strDecode; int nValue; int i = 0; while (i < DataByte) { if (*Data != '\r' && *Data != '\n') { nValue = DecodeTable[*Data++] << 18; nValue += DecodeTable[*Data++] << 12; strDecode += (nValue & 0x00FF0000) >> 16; if (*Data != '=') { nValue += DecodeTable[*Data++] << 6; strDecode += (nValue & 0x0000FF00) >> 8; if (*Data != '=') { nValue += DecodeTable[*Data++]; strDecode += nValue & 0x000000FF; } } i += 4; } else { Data++; i++; } } return strDecode; } static std::string base64Encode(const unsigned char* Data, int DataByte) { //编码表 const char EncodeTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; //返回值 std::string strEncode; unsigned char Tmp[4] = { 0 }; int LineLength = 0; for (int i = 0; i < (int)(DataByte / 3); i++) { Tmp[1] = *Data++; Tmp[2] = *Data++; Tmp[3] = *Data++; strEncode += EncodeTable[Tmp[1] >> 2]; strEncode += EncodeTable[((Tmp[1] << 4) | (Tmp[2] >> 4)) & 0x3F]; strEncode += EncodeTable[((Tmp[2] << 2) | (Tmp[3] >> 6)) & 0x3F]; strEncode += EncodeTable[Tmp[3] & 0x3F]; if (LineLength += 4, LineLength == 76) { strEncode += "\r\n"; LineLength = 0; } } //对剩余数据进行编码 int Mod = DataByte % 3; if (Mod == 1) { Tmp[1] = *Data++; strEncode += EncodeTable[(Tmp[1] & 0xFC) >> 2]; strEncode += EncodeTable[((Tmp[1] & 0x03) << 4)]; strEncode += "=="; } else if (Mod == 2) { Tmp[1] = *Data++; Tmp[2] = *Data++; strEncode += EncodeTable[(Tmp[1] & 0xFC) >> 2]; strEncode += EncodeTable[((Tmp[1] & 0x03) << 4) | ((Tmp[2] & 0xF0) >> 4)]; strEncode += EncodeTable[((Tmp[2] & 0x0F) << 2)]; strEncode += "="; } return strEncode; }

 

static std::string Mat2Base64(const cv::Mat &img, std::string imgType)
{
    //Mat转base64
    std::string img_data;
    std::vector<uchar> vecImg;
    std::vector<int> vecCompression_params;
    vecCompression_params.push_back(CV_IMWRITE_JPEG_QUALITY);
    vecCompression_params.push_back(90);
    imgType = "." + imgType;
    cv::imencode(imgType, img, vecImg, vecCompression_params);
    img_data = base64Encode(vecImg.data(), vecImg.size());
    return img_data;
}
 
static cv::Mat Base2Mat(std::string &base64_data)
{
    cv::Mat img;
    std::string s_mat;
    s_mat = base64Decode(base64_data.data(), base64_data.size());
    std::vector<char> base64_img(s_mat.begin(), s_mat.end());
    img = cv::imdecode(base64_img, CV_LOAD_IMAGE_COLOR);
    return img;
}