base64 decode + encode sample

ofApp.h

// reference : https://gist.github.com/satoruhiga/1687325

#pragma once

static int WIDTH = 300;
static int HEIGHT = 300;

#include "ofMain.h"

#include "Poco/Base64Encoder.h"
#include "Poco/Base64Decoder.h"


class ofApp : public ofBaseApp
{
    protected:
    string _base64ImageData = "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";
    
    ofImage _image;
    ofImage _image2;
    
    
	public:
        void setup()
        {
            
            _image = base64decode(_base64ImageData);
            
            string base64string = base64endode(_image);
            cout << base64string << endl; // <- 最初に入れたstrと違っている・・・！！
            
            _image2 = base64decode( base64string );
        }

    
    
		void draw()
        {
            //２つのほぼ同じイメージがみえる
            _image.draw(0, 0);
            _image2.draw(WIDTH*0.5,0);
        }
    
    
        // base64 str -> ofImage
        ofImage base64decode(string base64str)
        {
            stringstream ss;
            ss << base64str;
            Poco::Base64Decoder decoder(ss);
            
            ofBuffer buffer;
            decoder >> buffer;
            
            ofImage image;
            image.load(buffer);
            
            return image;
        }
    
        // ofImage -> base64 str
        string base64endode(ofImage image)
        {
            ofPixels pixel = image.getPixels();
            
            ofBuffer imageBuffer;
            ofSaveImage(pixel, imageBuffer);
            
            stringstream ss;
            ss.str("");
            
            Poco::Base64Encoder encoder(ss);
            encoder << imageBuffer;
            encoder.close();

            return ss.str();
        }


	
};