Image source not readable

hi friends this is my code

            if ($data->hasFile('product_img')) {
                $image = $data->file('product_img');
                $input['image_name'] = uniqid() . '.' . $image->getExtension();

                $destinationPath = public_path('/images/backend/products');
                $img = Image::make($image->getRealPath());
                $img->orientate()
                    ->resize(600, 600, function ($constraint) {
                        $constraint->aspectRatio();
                        $constraint->upsize();
                    })
                    ->save($destinationPath . '/' . $input['image_name']);
            }

thanks