I'm trying to upload an image to odoo via Php, but it doesn't work

My code:

/*getting image from bytea column in postgres sql*/

$imageOdoo = (String)base64_encode($line["data"]);

/*trying to upload to Odoo*/

$models->execute_kw($db, $uid, $password, 'product.template', 'write', array(array(2637), array('image_1920'=>$imageOdoo)));

The error i'm always getting is:

[_response] => faultCode 2 faultString This file could not be decoded as an image file. [_request]