Creating image from base64 string in NodeJS
I am trying to upload an image that I extract from a my canvas and post via ajax, and I have trouble creating the image file on my server side.
I have following this answer: https://stackoverflow.com/a/7347358/1358670 but still I seem to miss something here or there.
Here is my javascript (browser) code:
var img = myCanvas.toDataURL("image/jpeg");
// ajax request to send the image
and in server side, I do the following:
var fd = fs.openSync('./img.jpeg', 'w');
req.body.image = req.body.image.replace(/^data:image/w+;base64,/, "");
console.log( req.body.image );
var buff = new Buffer(req.body.image, 'base64');
fs.write(fd, buff, 0, buff.length, 0, function(err,written){
console.log( ">> "+ err );
fs.closeSync( fd );
});
As you can see, I've logged the image to see if it was properly sent, and IT IS, but still I can't open the created img.jpeg file
any help or hint is very welcome.
EDIT
I've also tried the solution in here: https://stackoverflow.com/a/6933413/1358670 but I still have the same problem
EDIT:2
I've tested my front-end side, with a PHP script in the server side, and the image produced was very good, so I would conclude that the problem is in my NodeJS code.
The problem was in the treatment on NodeJS, and I didn't doubt the code since it was the same every where with people commenting that its worked for them, nothing were different so I didn't doubt the process, but either something done wrong.
When checking it in my PHP script I've found a step that is not in the NodeJS code, and here is the PHP code:
$img = $_POST[ 'image' ];
$img = str_replace('data:image/jpeg;base64,', '', $img);
$img = str_replace(' ', '+', $img);
$data = base64_decode($img);
$file = "./". uniqid() . '.png';
$success = file_put_contents($file, $data);
print $success ? $file : 'Unable to save the file.';
The difference is here: str_replace(' ', '+', $img);
I don't know how it worked for others, but for me replacing EVERY space in the base64 by + solved my problem.
New NodeJS code
req.body.image = req.body.image.replace(/^data:image/w+;base64,/, "");
req.body.image = req.body.image.replace(/ /g, '+');
console.log( req.body.image );
var buff = new Buffer(req.body.image, 'base64');
fs.write(fd, buff, 0, buff.length, 0, function(err,written){
console.log( ">> "+ err );
fs.closeSync( fd );
});
I hope this will help someone else
A better version of the code:
req.body.image = req.body.image.replace(/^data:image/jpeg+;base64,/, "");
req.body.image = req.body.image.replace(/ /g, '+');
fs.writeFile('./records/'+model+'/out.jpeg', req.body.image, 'base64', function(err) {
console.log(err);
});