How to stream your Desktop of your Mac to your phone:
Aim:
After using ScreenBroadcasting and seeing the potential behind the application, I thought I'd put it to good use with mobile learning.
I'm guessing that the concept behind ScreenBroadcasting was driven by the medical development that the developers do on the OsiriX project - for more info click here.
I feel that there could be great potential for the application in mobile learning, with cell phones displaying medical still or video footage to hospital staff, medical students etc. for collaborative working.
To see proof of concept: - click here to download H.264 movie.
You will need QuickTime 7 player to view the file.
PC users - click here 14.7 Mb download.
What will you need:
Hardware: G4 Mac or above running OS X.
Software:
Download - ScreenBroadcasting - for more info click here. There is a small cost for ScreenBroadcasting.
Download - QuickTime Broadcaster - for more info click here. QuickTime Broadcaster is free.
1. Download all the applications listed above and install them.
After that, open the ScreenBroadcasting application. All you will see is the application icon in the Dock.
- Tip: a short cut to the Applications folder when in the Finder is to press "Shift + Apple key + A"
2. Next, we will open QuickTime Broadcaster and in this demo, I'll use 'Automatic Unicast'. The nice thing about Automatic Unicast is that the .sdp file you need will automatically be generated on the fly, on the server. For Automatic Unicast to work, you will to have to set up an account on the server. To set up account on your server, see your administrator or read the admin guide for QuickTime Streaming Server - for more info click here.
- Transmission: Automatic Unicast (Announce).
- Address: Your Streaming Server IP address: whatever your Administrator has given you.
- File: eg. 'shows/rave_home-adam' location to where your sdp will be generated. Note: no need to add .sdp at the end.
- Username: Your user name on the streaming server.
- Password: Your password on the streaming server..
- Buffer Delay: 8 - you can leave as default if you wish..
Note: In the bottom left hand side of the QuickTime Broadcaster window, under Location, you can see the URL that you will need to type into QuickTime Player eg. rtsp://10.0.6.27/shows/rave_home-adam.sdp You will also see that QuickTime Broadcaster has added '.sdp' to the end of the URL for you.
3. Now we will have a look at the settings for video. By default, you should see RGB DV listed on the Source pop-up menu.
- Enable Video Stream: tick
- Preset: Custom
- Source: RGB DV
- Compression:
- Width: 176
- Height: 144
- Compressor: H.263
- Options: tick 'Specify Encoded Image Resolution' & 176 x 144 (QCIF)
- Depth: Colour
- Quality: Medium - High - Best
- Frames per second: 6
- Key frame every: default if you wish & tick the box.
- Limit data rate to: 22 & tick the box.
4. Staying with the video settings, there is one last thing to do and that's set the packet size.
To set the Packet size, click on the 'Packetizer...' button at the bottom of the window. A little box will drop from above: in the 'bytes' box, type in 380
5. Now we will have a look at the settings for audio.
- Enable Audio Stream: tick
- Preset: 3G - GPRS
- Source: internal. (External mic if you have one.)
- Play-though speaker: your discretion but there is no point if the Mac is locked away in a server room.
- Gain (your discretion)
- Compressor: AMR Narrowband (this will be set up for you if you picked '3G - GPRS' from the Presets above).
- Rate: 8.000 kHz
- Size: 16 bit
- Use: Mono
6. Within the audio section, we will also have a look at the options for the AMR Narrowband compressor. In here, we will tick 4.75 kbit/s and then click on ok.
Now, all you have to do is to is click on 'Broadcast' and you should be up and running and streaming.
