geobray.com » HowTo

Live TV Streaming to iPhone with HTTP

George Bray — Fri, 26 Mar 2010 04:26:58 +0000

This "How To" recipe builds a transcoder to process live multicast streams into live and on-demand streams suitable for iPhone and similar devices.

This single-stream example uses a multicast transport stream containing MPEG-2, but could easily use a multicast or unicast stream in a different format. This example runs on Xserve and MacPro machines, it's a requirement that mediastreamsegmenter runs on OS X.

Warning: Reticulation of broadcast TV services requires the permission of the broadcaster.

Thanks to ANU for the opportunity to test this on a multicast-rich network.

Live BBC stream on iPhone via HTTP at 750Kbps

The Result

One live MPEG-2 transport stream transcoded to be visible on the iPhone. VLC (and x264) transcode the stream to the required format for mediastreamsegmenter, which then saves the stream on disk under the webserver. It continually updates the index file so viewers can keep up. Depending on the content, the bitrate of the stream can be 500-900Kbps.

Web page on iPhone with text links to .m3u8 index file

Viewing the stream in the iPhone simulator

Screen shot of iPhone movieplayer without controls overlaid

A mid-range server can transcode three standard-definition 720×576 MPEG-2 services.

Required Parts

A live MPEG-2 TV service
The VLC application from www.videolan.org
The mediastreamsegmenter program, free from Apple's Developer Connect

Documentation

mediastreamsegmenter Man Page

Apple's HTTP Live Streaming Documentation

IETF Standard Submission

VLC Command Line Help

Installation

The Apache webserver is running above a directory that will contain the media.
( /Volumes/mydisk/www/abc/ in this example).

The webserver is available to the outside
(http://mywebserver.edu/abc/ in this example)

Apache mime types to be added:
AddType application/x-mpegURL m3u8
AddType video/MP2T ts

VLC is expected to be at /Applications/VLC.app/

mediastreamsegmenter gets installed to /usr/bin/mediastreamsegmenter

Your source stream is playable in VLC.
( udp://@239.224.0.2:1234 in this example)

The Script

Save the script below to a text file, say abcstreamer.sh - ensure there are no carriage returns in the command lines. Customise the bold items in the command lines to suit your environment.

#!/bin/sh

rm -rf /Volumes/mydisk/www/abc/*

/Applications/VLC.app/Contents/MacOS/VLC udp://@239.224.0.2:1234 –intf=dummy –sout-transcode-audio-sync –sout='#transcode{vcodec=h264,venc=x264{aud,profile=baseline,level=30,keyint=30,bframes=0,ref=1,nocabac},acodec=mp4a,ab=56,deinterlace}:duplicate{dst=std{access=file,mux=ts,dst=-}}' | mediastreamsegmenter -O -b http://mywebserver.edu/abc/ -f /Volumes/mydisk/www/abc/ -t 10 -s 4 -D

Change permissions for you to execute it
chmod 744 abcstreamer.sh

Run it with
./abcstreamer.sh

The Stream

Watch the directory in the Finder to see the segments arrive. After a while the index file will be written, so you can now get the stream from your iPhone.

The stream should be available at

http://mywebserver.edu/abc/prog_index.m3u8

Open the URL in Safari on your iPhone. You can also use QuickTime Player X on a Mac desktop to "Open URL".

Serve It Up

Here's an index.html file for your web server showing text links to your stream. Alternatively, try the video tag in that fancy new HTML5 browser you downloaded.

iPhoneTV

iPhone TV

ABC

BBC

Stats

Peaks are starting a new stream.

Tips

These are by no means optimal settings, please post improvements in the comments.
Reset VLC's preferences to be sure you don't have any clashing settings.
Use mediastreamvalidator to debug the transport stream.
Consider DVBlast or Multicat as additional tools for streaming and routing.

Updates

Added stats

Many thanks to the Videolan and x264 devs, and hats off to ioncannon and nerdlogger for prior art.

Woktenna for 3G

George Bray — Sun, 07 Feb 2010 08:26:51 +0000

After looking for inexpensive external antennae I came upon a great thread on Whirlpool describing how to make your own. I also wanted a better way to measure the signal strength while I point the dish, and found this page detailing the AT commands for the Optus/Huawei E169.

On a spare Sunday afternoon I put it all together, and to my surprise, it works exceptionally well!

With the dongle plugged into my computer I rarely get a 3G service. With this woktenna I get 4-5 bars of 3G. The best I've got is number 13 or -87dBm, a workable connection with 5 bars solid.

Parts:

One Mesh fruit bowl from Myers $30
One Active USB cable (5m) from Jaycar $14.95
One Paper Towel Holder from a bargain shop $2
One beer coaster
An old speaker mounting bracket
Scraps of aluminium, bike parts and a drink bottle lid.

The focal point of the dish is 190^2/(4*105) = 85.95mm. This is just shy from the edge plane of the rim.

Here's a small ruby script that displays the signal strength directly from the Huawei E169. It requires

sudo gem install ruby-serialport

#!/usr/bin/ruby

#puts "hi"

require 'rubygems'

require 'serialport'

require 'readline'

sp = SerialPort.new "/dev/tty.HUAWEIMobile-Modem", 38400

sp.read_timeout == 200

1000.times do

sp.write "AT+CSQ\r\n"

j1 = sp.readline

t = Time.new.to_s

puts "TIME: " + t + "SIGNAL: " + sp.readline

sp.flush

sleep(1)

end

#puts "ho"

Broadband from the Beach

George Bray — Tue, 19 Jan 2010 01:01:30 +0000

Recipe

3G USB Modem with external antenna connector
Pigtail cable from USB modem to external antenna
DrayTek 2820n 3G/ADSL/Wifi Router
G-Spotter Broadband Antenna
Optional : Big Wifi Antenna

Commentary

I've used an Optus E169, and Telstra Sierra Wireless 301 USB modems in pre-paid mode to maintain great, permanent 3G connectivity in places where the service is unreliable via a 3G handset.

Both of these dongles have an external antenna connector.

I use an external antenna mounted on a tripod.

3G Long Range Antenna
http://www.broadbandantennas.com.au/

To share the 3G connection I use a Draytek Vigor2820n. This ADSL/Wifi router also has a USB port and displays the 3G radio reception signal strength in the browser. It redials the 3G connection on demand, if required.

Draytek Vigor2820n
http://www.draytek.com.au/products/Vigor2820.php

This was my setup while travelling recently. Using it I can scan the horizon for the strongest signal (much like peaking a satellite dish). In some remote places where there is no GSM service on phones I can at least get a GPRS service to the outside world.

If you can get a 3G service, adjusting the directional antenna can optimise it.

There's no webpage on either carrier showing you how much trafficyou've used with prepaid, you have to put the dongle in a laptop and (optus: send an SMS with their software, Telstra: use the connection app to query the balance).

The latency on both 3G services I used was fine for my use. I conduced multi-party (8) videoconferences with US and EU endpoints. Skype video fine, YouTube fine. No sweat with the 4Mbps connection I'd usually get. As a test, I was watching the recent Broadband Futures event streamed live to my beachside cabin – it worked fine.

Re-charging a Telstra prepaid connection takes (some time? - 48hrs). If you use the service before the credit is made to your account, the usage on the re-charge you bought is billed at the maximum price. Only after does the billing rate adjust to what you've just paid for.