Ajax not post base64 data of large image
I agree with TrueBlueAussie. This looks like a server side setting in PHP.
Open you php.ini file and find the line stating upload_max_filesize. The default it set to 2M, which is 2MB. Try increasing it to 3MB and see if you are still receiving the error.
Note: You'll need to restart Apache/Nginx/webserver for this to take affect from the php.ini file.
Even though you are sending the file as a variable, the application/x-www-form-urlencoded might be interpreted in PHP as being an actual file upload. The other php.ini setting you can take a look at will be post_max_size which has a default of 8M, which is the maximum that you can POST to your PHP script.
First of all: the code that you indicate in base64 returns a corrupted image;when you send the code in base64, uses the function encodeURIComponent to avoid errors when sending.
Try this code:
var srcdata = "data:image/jpeg;base64,/9j/4SxvRXhpZgAASUkqAAgAAAANAAABBAABAAAAwAwAAAEBBAABAAAALAcAAA8BAgAIAAAAqgAAABABAgARAAAAsgAAABIBAwABAAAABgAAABoBBQABAAAAxAAAABsBBQABAAAAzAAAACgBAwABAAAAAgAAADEBAgAMAAAA1AAAADIBAgAUAAAA4AAAABMCAwABAAAAAQAAAGmHBAABAAAA9AAAACWIBAABAAAA3gkAAPAJAABTQU1TVU5HAFNBTVNVTkctU0dILUk1MzcAAEgAAAABAAAASAAAAAEAAABJNTM3VUNVQ05DOQAyMDE0OjA2OjIyIDEwOjE3OjEwACEAmoIFAAEAAACGAgAAnYIFAAEAAACOAgAAIogDAAEAAAADAAAAJ4gDAAEAAAB9AAAAAJAHAAQAAAAwMjIwA5ACABQAAACWAgAABJACABQAAACqAgAAAZEHAAQAAAABAgMAAZIKAAEAAAC AgAAApIFAAEAAADGAgAAA5IKAAEAAADOAgAABJIKAAEAAADWAgAABZIFAAEAAADeAgAAB5IDAAEAAAACAAAACJIDAAEAAAAAAAAACZIDAAEAAAAAAAAACpIFAAEAAADmAgAAfJIHAGIAAABeCQAAhpIHAFwGAADuAgAAAKAHAAQAAAAwMTAwAaADAAEAAAABAAAAAqAEAAEAAADADAAAA6AEAAEAAAAsBwAABaAEAAEAAADACQAAF6IDAAEAAAACAAAAAaMDAAEAAAABAAAAAqQDAAEAAAAAAAAAA6QDAAEAAAAAAAAABKQFAAEAAABKCQAABqQDAAEAAAAAAAAACaQDAAEAAAAAAAAACqQDAAEAAAAAAAAAIKQCAAsAAABSCQAAAAAAAAEAAAAUAAAABAEAAGQAAAAyMDE0OjA2OjIyIDEwOjE3OjEwADIwMTQ6MDY6MjIgMTA6MTc6MTAAAQAAABQAAAAUAQAAZAAAAFAAAAABAAAAAAAAAAoAAAAUAQAAZAAAAHIBAABkAAAAQVNDSUkAAABLSktKFwUHhQABAF4AAQAAAAAAAAAAkaMAAQAAAAFYZAABAAAAAFJqAAT4awAFib0AAhBHAAAAAAAAT6EAAQAAAAGFbQABTIgAAQAAAAGAPQAB1GYAAR/F//8L1QAAzfH//yRxAAENngAAFK4AAErK// giAABS0pLSmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGVXEABVVxAAVVcQAFmWAACWZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABZlwAAlmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAWZcAAJZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABlVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFmXAACWZxAAZmcQAGZnEABmZxAAZmcQAGZnEABplwAAlVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABZlwAAlmcQAGZnEABmZxAAZmcQAGZnEABmZxAAaZcAAJVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAWZcAAJZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGmXAACVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFmXAACWZxAAZmcQAGZnEABmZxAAZmcQAGZnEABplwAAlVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABZlwAAlmcQAGZnEABmZxAAZmcQAGZnEABmZxAAaZcAAJVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAWZcAAJmXAACWZxAAZmcQAGZnEABmZxAAZmcQAGmXAACVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFmWAACZlwAAlmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGVXEABVVxAAVVcQAFVXEABVVxAAVVcQAFVXEABZlgAAmZcAAJZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAYRUAABmXAACWZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZmcQAGZnEABmZxAAZLSktKAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAASLAAAf/8AACRQAABVo8AAf/3AAB25wABAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAATv8AAf/2AACFNwABTv8AAf/2AACFNwABT5QAAf/2AACFXgABT5QAAf/2AACFXgABAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEtKABYAAEZBRkEAHIjEAAEAHOcsAAEAMRzRAAIARn5sAAIAWwYuAAMAcAgFAAMAmtFlAAEAmnjxAAEAmpN5AAEAjPohAAEAfnrCAAIAcNwgAAIAYjlTAAMAVDJzAAMARuH8AAIAVOH8AAIBgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAABgQAAAAAAAAAARkFGQQADAD8AAwArAABGQUZBABg8AAAAPAAAAFMwOFFFTENHQzAxAAcAAQAHAAQAAAAwMTAwAgAEAAEAAAAAIAEADAAEAAEAAAAAAAAAEAAFAAEAAABaAAAAQAAEAAEAAAAAAAAAUAAEAAEAAAABAAAAAAEDAAEAAAAAAAAAAAAAAAAAAAAAAAAAAgABAAIABAAAAFI5OAACAAcABAAAADAxMDAAAAAAAQAAAAEABAAAAAICAAAAAAAACQAAAQQAAQAAAAABAAABAQQAAQAAAJAAAAADAQMAAQAAAAYAAAASAQMAAQAAAAYAAAAaAQUAAQA `"; var count = 1; var name = 'test'; $.ajax({ type: "POST", url: "./createImage.php", data: { img_data:srcdata, img_id:count, name:name }, cache: false, contentType: "application/x-www-form-urlencoded", success: function (result) { alert(result); } });<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>