Lets take a run through and crop a video.  This will provide you some hands on experience of how the interface works.  

Goal: Our goal is to get the above video of the bike, and take out the "525 Chain conversion" part.  We are going to clip that out so that it's not visible, and create a new video in the process.  In addition, the source video is in the "Apple Intermediate Codec" format. You can see it's 197.4Mb and we'd like to reduce that to something more sensible.

What we'll do is specify a crop area, have Stomp output the video using a medium quality H264 and also compress the PCM audio to AAC.  Lets begin!

1. Step one - get the video into Stomp.  In this example it's already done.  It's easy though: All you need to do is drag the video that you want to compress into the main UI area.  Or if you like click the + button on the left hand side to bring up an Open dialog so that you can add media that way.
2. Choose H264 as the preset.
3. At this point you should also unlock the presets, so they can be edited. Press the Unlock icon to the right hand side of the settings panel. It's a simple toggle switch that prevents unintentional changes to existing presets.
4. With the preset now unlocked you can click on the crop option to enable it.  You'll notice a "marching ants" overlay on the video. Resize this so that it's like the picture.
5. In order to compress the audio into AAC we need to do ... nothing!  Stomps H264 preset is setup by default to compress to AAC. If you're curious, click the "Settings..." button to the right of "Recompress Audio" and it'll show you what it's setup to do.
6. That's it!  Click the Process button to kick off the compression.