Hi, On Wednesday 16 March 2011 05:50:11 Kim, HeungJun wrote: > 2011-03-16 ìì 9:14, Laurent Pinchart ì ê: [snip] > > What bothers me with your auto-focus implementation is that the user > > might want to perform auto-focus several times. Let's imagine this use > > case: > > > > 1. The user points the camera (webcam, cellphone camera, digital camera, > > it doesn't matter) at an object. > > > > 2. The user presses a button to perform singleshot auto-focus (it can be > > a physical button or a button on the camera screen, once again it > > doesn't matter). > > > > 3. The application sets the focus control to AUTO. > > > > 4. The driver and device perform auto-focus once. The lens is moved so > > that the object is in focus. > > > > 5. The user points the camera at another object. > > > > 6. The user presses a button to perform singleshot auto-focus. > > > > 7. The applications sets the focus control to AUTO. As the focus control > > value was already AUTO, nothing is done. > > > > This is clearly broken. That's why we need a V4L2 button control in > > addition to the menu control. > > Yes. Youre'rignt. The menu control dosen't called one more with the same > value. It's now worked I know. But, the reason why I choose menu type for > focus, is because the menu type can let the user-application know how many > kinds of focus this sensor have & support, using querymenu. The only way > letting know, is currently the menu type. > > On the other hand, not-working twice or more executions is handled by > user-application. The user-application want twice auto focus, it calls > AUTO-Manual-(or any other control value)-and AUTO once again. It's wierd, > but It can satisfy application and drivers. > > And, but it might be irrelevant, the user-application(or upper layer > platform) can determine how to draw & arrange the UI objects after it > knows the kinds of focus method at last. > > It may be a time to need another type of control. And such control should > satisfy these: 1. letting the user-application know how many kinds in the > controls(like a querymenu) 2. being available to be called one more. > > How about your opinion? I think we need a menu control (to select the focus type) and a button control (to run singleshot auto-focus). When the menu control is in auto-focus mode, setting the button control will run the auto-focus algorithm once. Is the macro focus mode a singleshot focus or a continuous auto-focus ? -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
