Base 64 encode image. Upload twitter avatar

I'm trying to make an image upload form for twitter to change avatar. Twitter says the image has to be base 64 encoded before I upload it. So here's a sample

https://dev.twitter.com/docs/api/1/post/account/update_profile_image

How can I do this so far I've been getting errors

PHP Code:

<?php // process form data 
    if ($_POST['image']){ 
        // post profile update 
        $post_data = array( 
            "image" => $_POST['image'] 
        ); 

         $post_data = base64_encode($post_data); 

        echo $post_data; 
        } 
        else{ 
        echo     
        "  <form action='post.php' method='POST' enctype='multipart/form-data'> 
<br><input type='hidden' name='image' value='update_profile_image'> 

    <input type='file' name='image' size='30'/><br> 

    <input type='submit' value='开发者_C百科Upload' class='button'/> 


    </form>";} 

    ?>

Please help

From the looks of this, you aren't retrieving the image from the POST at all. The image itself will be available in $_FILES

// See what's in $_FILES
var_dump($_FILES);

// You need the temporary name of your image from $_FILES
$filedata = file_get_contents($_FILES['image']['tmp_name']);
$post_data = base64_encode($filedata);

// Now you should have a base64 ascii string
echo $post_data;

This should do it. Move the uploaded file to a directory because you cannot get required results by encrypting the [tmp_name]

if ($_FILES['image']){

move_uploaded_file($_FILES["image"]["tmp_name"], "path" .basename($_FILES["image"]["name"]));
$meh = file_get_contents("path/" .basename($_FILES["image"]["name"]));
$results = base64_encode($meh);
}