LLF Windows Encoder/Decoder

LLF Windows Encoder/Decoder
Updated January 29, 2001

Introduction

This information is in BETA. Please use at your own risk.

The Lending Library Format is described here. It allows media files to be loaned by a webserver and then played back for up to 24 hours using Microsoft's Media Player.

Two extra components are needed to make LLF work on Windows - the ISAPI filter that encodes the media as it's served to the user and a DirectShow filter that checks the date validity of the LLF file before allowing it to be played by Media Player.

DirectShow Filter

You can download the DirectShow filter here. To install:

Open the ZIP file and extract the contents to any folder on your PC - you can use \Windows\System if you want
Launch the batch file "register.bat"

You will now be able to open LLF files with Media Player and they will continue to play until the loan expires, at which point you'll see:

ISAPI Filter

This filter is available here. Follow these instructions to install:

Extract the contents of the ZIP file to a folder where you can run ISAPI extensions - see the IIS documentation. This doesn't have to be the same location as the media files.
Edit the "llfenc.reg" file (right click and choose Edit). You need to change the "FileLocation"="d:\\streams" line to reflect the folder where you've installed the contents of the ZIP. Don't forget that in registry files, you must use \\ rather than \ to seperate the folder names.
After you've saved changes to the registry file, double-click it to enter it's contents into the registry
Edit the contents of the llfenc_notfound.html and llfenc_checkedout.html files to customize them for your library. Make sure the special tag  is not deleted in the llfenc_checkedout.html file since the ISAPI filter will replace this with the date/time when the outstanding loan expires.

To construct a URL that runs the filter, you need to provide two parameters: file and email

file points to the Windows filename for the file that's to be served in LLF format with the Windows backslash replaced with a forward slashes. For example, if you wanted to serve "d:\streams\music\sample.mp3", the file parameter would be "file=d:/streams/music/sample.mp3.llf". Pay special attention to the filename extension - it needs both the real filename extension (mp3 in this case) and llf.

email points to the email address of the person borrowing the media. You should try to make sure that this is a correct email address, since we'll probably use it in the future. For now, it's used to determine if the user can download the file again within the 24 hour period or whether to tell a different user that the file is checked out.

So, if the ISASPI filter was accessed at http://www.coolstf.com/isapi/llfenc.dll, the full URL might be:

http://www.coolstf.com/isapi/llfenc.dll?file=d:/streams/music/[email protected]

How to get Help

If you're a user trying to playback an LLF file, please contact the owner of the website that provided the LLF file. If you're a web server administrator and you're trying to get the LLF ISAPI filter working, please contact us via email.