将Base64缓冲区另存为映像到磁盘

Question

in a Node.js app, i send an image via Socket.io to the server. in the server, i get it like this and i wanted to save it on the disk. it save's but i cant open that image and image viewer says it's damaged! file size is correct but i can't open it. is there anything that i miss in the code?

    socket.on('newImage', function (data) {
       var img = data.image;
       var coded_img = new Buffer(img, 'base64');

       fs.writeFile("out.png", coded_img,'base64', function(err) {
             if (err) throw err;
             console.log('File saved.')
       });
    });

Answer 1

I solved it, With this function, i recovered main image data:

decodeBase64Image = function(dataString) {
    var matches = dataString.match(/^data:([A-Za-z-+\/]+);base64,(.+)$/),
        response = {};

    if (matches.length !== 3) {
        return new Error('Invalid input string');
    }

    response.type = matches[1];
    response.data = new Buffer(matches[2], 'base64');

    return response;
};