Your first script
It's time to create your first script. Go to the Filters tab and expand the Debug category. Double-click Version and the text Version() will appear in the editor. Highlight Version() and the Parameters tab automatically becomes visible. At the top of the tab is a dropdown list that says Core::Version and below that is empty space. Core::Version tells you that you're using an AviSynth Core filter (built in to AviSynth) called Version. If there was more than one Version filter you could click the arrow next to it and select the correct one. The blank space tells you there are no parameters to enter.
The Preview Window allows you to test the output from your script. On the Extras menu click Preview. The output from the Version filter is information about the AviSynth version you're using. Pressing
The parameters tab
Now that you know how to create a script it's time to learn about parameters. Some filters, like Version, don't have any parameters. Most filters do have parameters, some of which are required, and some of which are optional. In order to learn how to work with them we're going to look at the AVISource filter. If you don't have an AVI file to open you can save your version script (select Save As from the File menu) and use it like a normal AVI. Start a new script by clicking the furthest button on the left side of the toolbar or selecting New from the File menu. Go to the Filters tab, expand the Source category, and add the AVISource filter to your script. Highlight the filter in the editor and look at the Parameters tab. Once again you'll see that this is a Core filter, but this time there are 3 parameters listed - filename, [audio], and [pixel_type]. The brackets around the last 2 parameters indicate that they are optional so you don't have to enter anything in them. Click the button next to the filename parameter and a window will open for you to select an AVI to open. Preview the script and start playing the AVI. Now close the preview and select the field next to the audio parameter. Change it to false by clicking the button to the right and selecting false. Preview your script again. If you're opening the Preview script nothing will change since it didn't have any audio to begin with. If it's a normal AVI (with sound), the video will still play, but there won't be any sound.