Dave, I think you are slightly missing my point. This query is not related to continuous auto focus. Let me try to explain again.
Say for instance you have a hardware platform with an auto focus module that requires power to hold the lens in position (except for the infinity position). When autoFocus() called, the power to the AF module is enabled and the auto focus algorithm runs moving the lens until focus is achieved. Assume the lens position is now not in the infinity position, so in order to maintain the lens position you must keep the auto focus module powered up. The AF process is complete and a callback is made to the application to denote the focus status. If the user now simply releases the half pressed capture key, not performing a capture, how is the CameraHardwareInterface layer to know that it should now turn power off to the AF module and let the lens move back to the infinity position? The auto focus module power is not the only thing that gets locked during the camera key half press. Other algorithms run and lock and need to be released when the user simply releases the key. Steve. On Feb 10, 11:30 am, Dave Sparks <[email protected]> wrote: > When you call autoFocus(), you get a callback after focus is completed > with a success or fail indicator. This is where you would display your > in-focus indicator in the view finder. If the user releases the > shutter button, then the app does nothing. If the user presses the > shutter button, you call takePicture(). > > We don't have an API that supports continuous auto-focus. This is > where the user holds the shutter half-down and the lens is > continuously. This is an enhancement that will probably come in the > Donuts release. > > On Feb 10, 8:24 am, steve2641 <[email protected]> wrote: > > > > > Hi, > > > I'm trying to understand how to implement a solution for a two stage > > camera key. There is an "autoFocus()" call in the Java world which > > translates down to an "autoFocus()" call CameraHardwareInterface. > > This seems to be the proper place to direct the camera key half press > > event, but how is the release event of camera key half press > > communicated down to the CameraHardwareInterface? > > > A typical scenario for the camera key half press is that a number of > > algorithms are kicked off and at the completion the results are locked > > in until either a capture occurs or the user releases the camera key. > > The case of a capture occuring is handled by the APIs, but again the > > case where the user releases the camera key does not seems to be > > considered, or I'm totally missing it :) > > > One of the more common, and obvious, examples of the use of a camera > > key half press release event/call is the focus indication. On many > > cameras, and some mobile devices, when the user half presses the > > camera key an indication of the focus state is shown in preview > > window. This indication will often be a small box in the center of > > the window. While the user continues to hold the camera key in the > > half pressed state, this indication will stay on the screen. When the > > user releases the camera key, this indication will disappear. In > > order to allow this indication to be drawn within the > > CameraHardwareInterface implementation, as well as to unlock the other > > less obvious half press features, a half press release event/call is > > needed. > > > Thoughts? > > > Steve.- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ unsubscribe: [email protected] website: http://groups.google.com/group/android-porting -~----------~----~----~----~------~----~------~--~---
