Required software:

• DivX Codec
• VirtualDub
• Xfire

0. Enable the developer console

In order to run use console commands, you must first enable the developer console. At the main L4D menu:

1. Click Options
2. Click Keyboard/Mouse
3. Change Allow Developer Console to enabled
4. Click Done

1. Record a demo using the source engine

Recording a demo in L4D is the same as any other source game. A demo doesn’t save an actual video; it saves the sound and the movements in game. To record a demo:

1. Join the L4D game
2. Press the tilde (~) to bring down the console
3. Type “record mydemo_01″
4. Play the game like normal
5. Type “stop” in the console when the game is finished

2. Play back the demo while recording in Xfire

Before recording anything with Xfire, change your resolution. For YouTube, the minimum resolution (640 x 480) will work just fine. Recording these videos consumes a large amount of space and the bigger your resolution – the more space it takes. I change my resolution to 640 x 480 and put it in windowed mode so that I can easily flip back and forth. Unforunately, it seems I have to also restart L4D when I change my video settings.

1. Lower resolution to 640 x 480
2. Make sure Xfire is running
3. Open the console (~)
4. Type “playdemo mydemo_01″
5. Wait for the map to load
6. Press [Scroll lock] + V to start recording with Xfire
7. When finished, press [Scroll lock] + V to stop recording with Xfire
8. Type stopdemo to stop the demo

3. Convert from the Xfire avi format to Divx

Xfire uses a special codec when it records the demo from L4D. In order to get this into a friendlier format, we need to use VirtualDub to convert it. Converting this format will also reduce the file size by A LOT which will make it a lot quicker to upload to YouTube.

1. Open up VirtualDub
2. Open your video in the Xfire videos folder (on Vista mine is):
   C:\ProgramData\Xfire\videos
3. Click Video
4. Click Compression
5. Click Divx Codec
   (If you do not see the Divx Codec, you don’t have Divx installed. Install it from divx.com)
6. Click File
7. Click Save As Avi

Now it should be MUCH smaller in size, perfect for uploading to Youtube!

Here is an example of me booming the survivors on Blood Harvest:

Miscellaneous

Recording your own voice

The only way that I know of to reliably record your own voice is by using the following console command:

voice_loopback 1

Basically, all it does is play whatever you say into your microphone back through your speakers/headphones. This is incredibly annoying, but so far I don’t know of a better way. Most of the time I just leave it off.

Useful console commands when recording the video of a demo

Some useful console commands that may be of some use when recording your demo playback. These require “sv_cheats 1″ to be run first.

Problems I still have…

• Unable to use a free camera – I definitely would like to figure out how to record using a free camera.
• Still unable to remove parts of the HUD
• Not sure how to remove glow (necessary?)

References:

• Recording a demo in L4D
• Useful console commands when playing a demo
• Essential Console commands
• L4D Community AutoExec
• Complete list of L4D Console commands
• Using Third-Person view in L4D
• Recording a video in L4D on Tactical Gamer