Help with capturing requirements from scenarios

Hello,

Travis has asked for some help with getting the requirements distilled 
from our scenarios document for GetUserMedia:
https://dvcs.w3.org/hg/dap/raw-file/tip/media-stream-capture/scenarios.html

There are some requirements that are really obvious, like these, all 
distilled from 2.1 "Check out my new hat!":

- Abilty to show the image stream from a camera on the screen
- Ability to capture a still image from camera and store the result
- Ability to trigger image capture from a timed event, not just from a 
button click
- Ability to capture sound and store the result
- Ability to display the volume of sound captured from from a microphone
- Abillity to trigger an event based on the volume of sound over some 
time (silence, in this case)

Many of these are covered in the numbered list under the scenario; some 
might not be, and some of the numbered items are out of scope for this 
WG (file upload, for instance).

I'd like to ask the TF to help with doing this distillation work:
- Check the scenarios document
- Help summarize and aggregate the requirements
- If there are requrements you think should be removed, or added, 
identify them

If we can get the requirements explicit on the list, that is an 
important aid in capturing them in the document.

                       Harald