Derived from Product Requirements

We will break down requirements into each phase of use:

Boot / Shutdown

The software must:

1. Respond to an input device to initiate system boot.
2. Initialize from external flash.
3. Initialize all device subsystems, handling failure gracefully.
4. Shutdown gracefully, preserving device state so that use can resume on boot.

Capture

The software must:

1. Display a low-latency video from the image sensor on the screen.
2. Respond to an input device to initiate an image capture.
3. Display a view of the captured image to the user.
4. Store the captured image on the removable memory.

Review

The software must:

1. Display captured images to the user.
2. Respond to an input device to display the photo selected by the user.