wp_stream_image example

$w    = $size['width'];
    $h    = $size['height'];

    $ratio = _image_get_preview_ratio( $w, $h );
    $w2    = max( 1, $w * $ratio );
    $h2    = max( 1, $h * $ratio );

    if ( is_wp_error( $img->resize( $w2, $h2 ) ) ) {
        return false;
    }

    return wp_stream_image( $img, $post->post_mime_type, $post_id );
}

/** * Restores the metadata for a given attachment. * * @since 2.9.0 * * @param int $post_id Attachment post ID. * @return stdClass Image restoration message object. */
function wp_restore_image( $post_id ) {