I am getting a base64 string from the server for a png file and i would like to save this image on the file system. It looks like phonegap filewriter only supports binary. Does anyone know how i can convert this base64 string to use in phonegap. I was looking at window.atob and window.btoa but couldnt make sense of things.

I am getting a base64 string from the server for a png file and i would like to save this image on the file system. It looks like phonegap filewriter only supports binary. Does anyone know how i can convert this base64 string to use in phonegap. I was looking at window.atob and window.btoa but couldnt make sense of things.

• javascript
• android
• jquery
• cordova

• If its a single file then you can store it in local storage – Divesh Salian Commented Jan 29, 2014 at 8:37
• my requirement i to save it on the file system – vijar Commented Jan 29, 2014 at 8:39
• You may want to check this post, it saves dataUrl which is base64 to a png image on android file system – Hazem Hagrass Commented Jan 29, 2014 at 10:05

3 Answers 3

You can not use the PhoneGap FileWriter to write binary data. You'd need to write a plugin to send your base64 encoded data to the native side, encode it into binary then write it using native code.

Check out the plugins info at: HERE also take a look at the phonegap source code to see how we do the file writer and you can add some code to do the base64 decode before writing.

As far as I know, phonegap don't provide a way to save an image to the filesystem. You need a phonegap plugin to do that.
Canvas2Image nearly do what you want. It take a canvas id, extract a base64 string from the canvas and save it as an image. You can slightly alter the javascript part of the plugins to accept a base64 string instead of a canvas id.

Just found a good plugin to save BASE64 into filesystem.

Phonegap Image Resizer

window.imageResizer.storeImage(
  function(json) { 
    console.log('Saved to ' + json.url) 
  }, function (error) {
    console.log("Error : \r\n" + error);
  }, imageDataInBase64);

More detail see the ment imageresize.js