現在手機上的空間往往不夠，所以影片最好就是直接連到server 上透過串流回來看就好了，在tornado 上串流的 demo:

class StaticFileHandler(RequestHandler):

Alright this time I found the actual solution:

            # Note: only return HTTP 206 if less than the entire range has been
            # requested. Not only is this semantically correct, but Chrome
 

            # refuses to play audio if it gets an HTTP 206 in response to
            # ``Range: bytes=0-``.

This note applies to audio only, chrome will play video that begins be returning a 206.

    @asynchronous
    @gen.coroutine
    def get(self, path, include_body=True):
        #Assume that path is correct, validation will be handeled elsewhere
 

        self.absolute_path = os.path.abspath(path)
        self.path = self.absolute_path
        if self.absolute_path is None:
            return

        self.modified = self.get_modified_time()
        self.set_headers()

        if self.should_return_304():
            self.set_status(304
 
)
            return

        request_range = None
        range_header = self.request.headers.get("Range")
        if range_header:
            # As per RFC 2616 14.16, if an invalid Range header is specified,
            # the request will be treated as if the header didn't exist.
            request_range = httputil._parse_request_range(range_header)

        if request_range:
            start, end = request_range
            size = self.get_content_size()
            if (start is not None and start >= size) or end == 0:
                # As per RFC 2616 14.35.1, a range is not satisfiable only: if
                # the first requested byte is equal to or greater than the
                # content, or when a suffix with length 0 is specified
                self.set_status(416)  # Range Not Satisfiable
                self.set_header("Content-Type", "text/plain")
                self.set_header("Content-Range", "bytes */%s" % (size, ))
                return
            if start is not None and start < 0:
                start += size
            if end is not None and end > size:
                # Clients sometimes blindly use a large range to limit their
                # download size; cap the endpoint at the actual file size.
                end = size

            self.set_status(206)  # Partial Content
            self.set_header("Content-Range",
                            httputil._get_content_range(start, end, size))
        else:
            start = end = None

        content = self.get_content(self.absolute_path, start, end)

        for chunk in content:
            self.write(chunk)
            yield gen.Task(self.flush)
        self.finish()