Getting error Undefined index: optimus_uploader_thumbnail_height

Hi:
I have integrated fineuploader-server with laravel 5.4 and followed all the steps as described here https://github.com/esbenp/fineuploader-server/blob/master/README.md
but getting error Undefined index: optimus_uploader_thumbnail_height.

I created following route :

Route::group(['prefix' => 'uploader'], function () {

Route::post('/upload', '\Optimus\FineuploaderServer\Controller\LaravelController@upload');
Route::delete('/delete/{uuid}', '\Optimus\FineuploaderServer\Controller\LaravelController@delete');
Route::get('/session', '\Optimus\FineuploaderServer\Controller\LaravelController@session');

});
but getting MethodNotAllowed error on Route::post('/upload', '\Optimus\FineuploaderServer\Controller\LaravelController@upload');

changing it to Route;:get and changing method to 'GET' and paramsInBody to false.
This is my javascript code:

``javascript
var restrictedUploader = new qq.FineUploader({
element: document.getElementById("fine-uploader-validation"),
template: 'qq-template-validation',
request: {
endpoint: "{{url('/').'/uploader/upload'}}",
method: 'GET',
paramsInBody:false
},
thumbnails: {
placeholders: {
waitingPath: "{{asset('/libraries/fine-uploader/placeholders/waiting-generic.png')}}",
notAvailablePath: "{{asset('/libraries/fine-uploader/placeholders/not_available-generic.png')}}"
}
},
validation: {
allowedExtensions: ['jpeg', 'jpg', 'png'],
itemLimit: 1,
sizeLimit: 51200 // 50 kB = 50 * 1024 bytes
}
});
``

where am i making mistakes ?