Try changing your js-script this:
<script>$('#editor').redactor({ imageUpload: "/{{$post->id}}/postimage"});</script>
In the upload function return the path of the image after upload
public function postImage($blogId)
{
$path = base_path().'/public/uploads/img/posts/' . (int)$blogId;
$image = Input::file('photo');
if (Input::hasFile('photo'))
{
$fileName = $file->getClientOriginalName();
$image->move($path,$fileName);
$image = new Image;
$image->name = $fileName.name;
$image->save();
// resizing an uploaded file
Image::make($image->getRealPath())->resize(300, 200)->save($path.'thumb-'.$fileName);
Image::make($image->getRealPath())->resize(300, 200)->save($path.'thumb-'.$fileName);
// Return Image path as JSON
if ($file->move($path, $fileName))
{
return Response::json(array('filelink' => $path . '/' . $fileName));
}
}
}