Stop mipmap level from dropping

{
    "providers": [
        {
            "type": "bitmap",
            "file": "minecraft:item/font/ascii.png",
            "ascent": 10,
            "height": 12,
            "chars": [
                "\u0061\u0062\u0063\u0064\u0065\u0066\u0067\u0068\u0069\u006a\u006b\u006c\u006d\u006e\u006f\u0070",
                "\u0071\u0072\u0073\u0074\u0075\u0076\u0077\u0078\u0079\u007a\u0041\u0042\u0043\u0044\u0045\u0046",
                "\u0047\u0048\u0049\u004a\u004b\u004c\u004d\u004e\u004f\u0050\u0051\u0052\u0053\u0054\u0055\u0056",
                "\u0057\u0058\u0059\u005a\u0020\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0020"
                ]
        }
    ]
}

Is my .json file for defnining the font, the attached image is the .png file with the characters. 
Is there any way to stop this from breaking the mip map? The problem is that my characters are 13 pixels high which doesn't really fit any reasonable power of 2