src/ResponseFactory.php
private function getXsendfileHeaders(ImageResource $resource, array $originalHeaders = [])
    {
        return array_merge($originalHeaders, [
            'content-disposition' => sprintf('inline; filename="%s"', basename($file = $resource->getPath())),
            'content-lenght' => filesize($file),
            'x-sendfile' => $file
        ]);
    }
private function getXsendfileHeaders(ImageResource $resource, array $originalHeaders = [])
    {
        return array_merge($originalHeaders, [
            'content-disposition' => sprintf('inline; filename="%s"', basename($file = $resource->getPath())),
            'content-lenght' => filesize($file),
            'x-sendfile' => $file
        ]);
    }
getXsendfileHeaders

@param ImageResource $resource
@param array $originalHeaders

@return array