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字符数组的base64编解码
base64.h
#include <string>std::string base64_encode(unsigned char const* , unsigned int len);std::string base64_decode(std::string const& s);
base64.cpp
#include "base64.h"#include <iostream>static const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ""abcdefghijklmnopqrstuvwxyz""0123456789+/";static inline bool is_base64(unsigned char c) {return (isalnum(c) || (c == '+') || (c == '/'));}std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {std::string ret;int i = 0;int j = 0;unsigned char char_array_3[3];unsigned char char_array_4[4];while (in_len--) {char_array_3[i++] = *(bytes_to_encode++);if (i == 3) {char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);char_array_4[3] = char_array_3[2] & 0x3f;for(i = 0; (i <4) ; i++)ret += base64_chars[char_array_4[i]];i = 0;}}if (i){for(j = i; j < 3; j++)char_array_3[j] = '\0';char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);char_array_4[3] = char_array_3[2] & 0x3f;for (j = 0; (j < i + 1); j++)ret += base64_chars[char_array_4[j]];while((i++ < 3))ret += '=';}return ret;}std::string base64_decode(std::string const& encoded_string) {int in_len = encoded_string.size();int i = 0;int j = 0;int in_ = 0;unsigned char char_array_4[4], char_array_3[3];std::string ret;while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {char_array_4[i++] = encoded_string[in_]; in_++;if (i ==4) {for (i = 0; i <4; i++)char_array_4[i] = base64_chars.find(char_array_4[i]);char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];for (i = 0; (i < 3); i++)ret += char_array_3[i];i = 0;}}if (i) {for (j = i; j <4; j++)char_array_4[j] = 0;for (j = 0; j <4; j++)char_array_4[j] = base64_chars.find(char_array_4[j]);char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];for (j = 0; (j < i - 1); j++) ret += char_array_3[j];}return ret;}
测试文件 base64_test.cpp
#include "base64.h" #include <iostream> int main() { const std::string s = "hello world\n11111111111 & 333333333\n444 dasssss" ; std::string encoded = base64_encode(reinterpret_cast<const unsigned char*>(s.c_str()), s.length()); std::string decoded = base64_decode(encoded); std::cout << "encoded: " << encoded << std::endl; std::cout << "decoded: " << decoded << std::endl; return 0; }
运行测试:
当前目录下执行
g++ -c base64.cpp 编译成.o格式g++ -c base64_test.cpp 编译成.o格式ar -rc base64.a base64.o 打包成静态库文件g++ -o test base64_test.o base64.a 链接成可执行文件./test运行可执行文件
图片的base64位编解码
base64.h
#include <string>using namespace std;class ZBase64{public:/*编码DataByte[in]输入的数据长度,以字节为单位*/string Encode(const unsigned char* Data,int DataByte);/*解码DataByte[in]输入的数据长度,以字节为单位OutByte[out]输出的数据长度,以字节为单位,请不要通过返回值计算输出数据的长度*/string Decode(const char* Data,int DataByte,int& OutByte);};
base64.cpp
#include "base64.h"string ZBase64::Encode(const unsigned char* Data,int DataByte){//编码表const char EncodeTable[]="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";//返回值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;}string ZBase64::Decode(const char* Data,int DataByte,int& OutByte){//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'};//返回值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;OutByte++;if (*Data != '='){nValue += DecodeTable[*Data++] << 6;strDecode+=(nValue & 0x0000FF00) >> 8;OutByte++;if (*Data != '='){nValue += DecodeTable[*Data++];strDecode+=nValue & 0x000000FF;OutByte++;}}i += 4;}else// 回车换行,跳过{Data++;i++;}}return strDecode;}
测试 base64_test.cpp
用到了opencv来读取图片, ubuntu下的opencv安装教程可参考:/luanpeng825485697/article/details/81181825
#include<opencv2/opencv.hpp>#include<iostream>#include"ZBase64.h"#include<vector>using namespace std;using namespace cv;void main(){Mat img = imread("1.bmp");vector<uchar> vecImg; //Mat 图片数据转换为vector<uchar>vector<int> vecCompression_params;vecCompression_params.push_back(CV_IMWRITE_JPEG_QUALITY);vecCompression_params.push_back(90);imencode(".jpg", img, vecImg, vecCompression_params);ZBase64 base64;string imgbase64 = base64.Encode(vecImg.data(), vecImg.size());//实现图片的base64编码cout << imgbase64 << endl;}
运行测试:
当前目录下执行
g++ -c base64.cpp 编译成.o格式g++ -c base64_test.cpp 编译成.o格式ar -rc base64.a base64.o 打包成静态库文件g++ -o test base64_test.o base64.a 链接成可执行文件./test运行可执行文件
