Converting from MPEG-1 files is very straight forward, requiring no special decoding codecs. To conversion from MPEG-2 requires an MPEG-2 decoder. MPEG-4 may require multiple codecs.

As you can see from the table below, converting to MPEG-2 require some very specific parameters in height and width where you can use any size for MPEG-1.

Before we proceed it is important to note that the file extension conventions for MPEG movies are less than intuitive. Typically MPEG-1 files have an extension of MPG or MPEG where MPEG-2 and MPEG-4 files have an almost unlimited variety of extensions including AVI.

Since this is so confusing, in the below example we are going to assume that you wish to convert and MPEG-1 file to a specific MPEG-4 format by selecting a codec and you will save the files as AVI.

The Fx MPEG Writer interface opens with the "Movie in" and "Movie out" fields empty. The "Video Format" drop-down list will have the last format you used selected. To convert your MPEG-1 file to MPEG-4 we will select AVI from the "Video Format" drop-down list.

To select the movie in, click the "Source" button and browse to the location of your file.

You can set some properties of the movie you intend to create from the Fx MPEG Writer interface, others must be set from within the codec's interface. There's no standard for AVI codec interfaces so you'll have to experiment.

If you want to change the size of your target movie, set the "AVI Target Width/Height" in the Fx MPEG Writer interface just in case the codec doesn't have that ability (or it doesn't work, which happens often).

When you click the "Start" button to encode your new, converted file, a list of the codecs that are installed on your computer will be displayed. Codecs are installable components, therefore the list below may not even resemble the codecs that are installed on your computer.

Some of the codecs are clearly identified as MPEG-4 where in other cases they are displayed using the brand name only. We have selected the DivX 6 codec below.

Clicking the "Configure" button on the codec selection window will display the interface that was created by the codec manufacturer. These interfaces vary widely; some have almost no configurable settings where others are very complicated. For more information about how to configure a particular codec you can normally find help on the manufacturer's web site.

We have accepted the default values from the above and now the conversion process starts.

There may be a long delay while the file is being parsed depending upon file size. When loading a very large file, if Windows is busy it may seem that the program is hung simply because Windows is keeping the processor for itself and not permitting Fx MPEG Writer to update progress.

The same thing is true after the file has been converted and Windows is cleaning up the temp files. That is, the Fx MPEG Writer progress bar might show 100% converted but the mouse pointer and interface will still show busy. Wait until the button text changes to Start for Stop before trying to close the application.

Note: You can speed up conversion significantly by defragmenting your hard drive.

In our example, after the target was encoded the file extension was automatically changed to "divx" by Fx MPEG Writer because we had that option selected.