Canon PowerShot V10 Advanced User's Manual page 49

Note
You can tap [ ] to activate autofocus during standby, after
which focusing is locked. The icon changes to [
focusing, tap it again.
If [ ] is not displayed, press the <
A green frame appears once the subject is in focus. A yellow
frame is displayed with [!] when the camera cannot focus on
subjects.
Caution
If you perform camera operations during movie recording, the
camera's built-in microphone may also record sounds of the
camera operations.
> key.
49
]. To unlock