Um dies zu konvertieren, benötigen Sie einen Encoder und Decoder, den Sie von Base64Coder erhalten - einem Open-Source-Base64-Encoder / Decoder in Java . Es ist die Datei Base64Coder.java, die Sie benötigen.
Um nun gemäß Ihren Anforderungen auf diese Klasse zugreifen zu können, benötigen Sie die folgende Klasse:
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
public class Base64 {
public static void main(String args[]) throws IOException {
/*
* if (args.length != 2) {
* System.out.println(
* "Command line parameters: inputFileName outputFileName");
* System.exit(9);
* } encodeFile(args[0], args[1]);
*/
File sourceImage = new File("back3.png");
File sourceImage64 = new File("back3.txt");
File destImage = new File("back4.png");
encodeFile(sourceImage, sourceImage64);
decodeFile(sourceImage64, destImage);
}
private static void encodeFile(File inputFile, File outputFile) throws IOException {
BufferedInputStream in = null;
BufferedWriter out = null;
try {
in = new BufferedInputStream(new FileInputStream(inputFile));
out = new BufferedWriter(new FileWriter(outputFile));
encodeStream(in, out);
out.flush();
}
finally {
if (in != null)
in.close();
if (out != null)
out.close();
}
}
private static void encodeStream(InputStream in, BufferedWriter out) throws IOException {
int lineLength = 72;
byte[] buf = new byte[lineLength / 4 * 3];
while (true) {
int len = in.read(buf);
if (len <= 0)
break;
out.write(Base64Coder.encode(buf, 0, len));
out.newLine();
}
}
static String encodeArray(byte[] in) throws IOException {
StringBuffer out = new StringBuffer();
out.append(Base64Coder.encode(in, 0, in.length));
return out.toString();
}
static byte[] decodeArray(String in) throws IOException {
byte[] buf = Base64Coder.decodeLines(in);
return buf;
}
private static void decodeFile(File inputFile, File outputFile) throws IOException {
BufferedReader in = null;
BufferedOutputStream out = null;
try {
in = new BufferedReader(new FileReader(inputFile));
out = new BufferedOutputStream(new FileOutputStream(outputFile));
decodeStream(in, out);
out.flush();
}
finally {
if (in != null)
in.close();
if (out != null)
out.close();
}
}
private static void decodeStream(BufferedReader in, OutputStream out) throws IOException {
while (true) {
String s = in.readLine();
if (s == null)
break;
byte[] buf = Base64Coder.decodeLines(s);
out.write(buf);
}
}
}
In Android können Sie Ihre Bitmap zum Hochladen auf einen Server oder Webdienst in Base64 konvertieren.
Bitmap bmImage = //Data
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bmImage.compress(Bitmap.CompressFormat.JPEG, 100, baos);
byte[] imageData = baos.toByteArray();
String encodedImage = Base64.encodeArray(imageData);
Dieses "encodedImage" ist eine Textdarstellung Ihres Bildes. Sie können dies entweder zum Hochladen oder zum direkten Anzeigen in eine HTML-Seite wie folgt verwenden ( Referenz ):
<img alt="" src="data:image/png;base64,<?php echo $encodedImage; ?>" width="100px" />
<img alt="" src="data:image/png;base64,/9j/4AAQ...........1f/9k=" width="100px" />
Dokumentation: http://dwij.co.in/java-base64-image-encoder