- Add Audio streams by clicking the ‘Add Audio Stream’ button (right pane).
- Click on the Edit button to show the audio option screen.
- If you want to add audio from an external file, click on the 'Add External File' button and choose the file containing the audio you need. This does not necessarily have to be an audio only file.
- If no re-encoding is needed, set audio codec to Passthru.

Note: Depending on which container you have chosen, you can add multiple audio streams.

- Click on the 'Add Subtitle' button in the right hand panel. Choose whether you want a soft subtitle or to hard burn subtitle.
- If you have a subtitle file, you can drag it into the batch view. A subtitle will then be automatically added in the right pane.

Note: Depending on which container you have chosen, you can add more subtitles.

- Click the "Add Filter" button (right pane) and select the "Overlay" filter.
- Click the Load Image/Movie button and choose an image or video file.
- With the position X and Y offset options you can adjust the position of the image/video.

- Click on the ‘disc’ icon in the preset selector to save.

- Add the files whose data you want to compare.
- Click on the ‘Show Media Informtation’.
- Use the search field to filter text.

To extend the functionality of ffWorks so that you can also edit/convert media files, you need an FFmpeg file.

You can compile FFmpeg yourself. There are several tutorials or scripts available online. You can also download ready compiled versions or use Homebrew or Macports to compile your own version.
Once you have a working FFmpeg file, you can install it for ffWorks in two ways.
The first method is to drag the FFmpeg file into the ffWorks window.
A second method is by using the FFmpeg Manager (preferences).

Click on the + sign in the lower left corner. Then choose which version. The best choice is Static FFmpeg.
If you have compiled FFmpeg with Homebrew or MacPorts, choose the corresponding button.