Question

我想在相机保持不动时自动对焦Android相机。我正在寻找教程或示例如何做到这一点或至少是小样本，显示我可以用来挂钩此类事件的类。

Answer 1

对我而言，这是一种享受：

//set camera to continually auto-focus
Camera.Parameters params = c.getParameters();
//*EDIT*//params.setFocusMode("continuous-picture");
//It is better to use defined constraints as opposed to String, thanks to AbdelHady
params.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
c.setParameters(params);

Answer 2

尝试使用Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO或Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE。见下文：

Camera.Parameters params = camera.getParameters();
if (params.getSupportedFocusModes().contains(
    Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO)) {
  params.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
}
camera.setParameters(params);

在尝试使用手机之前测试手机是否支持您选择的模式非常重要，否则setParameters()会抛出运行时异常。（编辑代码现在正常工作）

Answer 3

以下代码适用于我。

设置自动对焦（预览类）：

Parameters params = camera.getParameters();
params.setFocusMode(Parameters.FOCUS_MODE_AUTO);
//some more settings
camera.setParameters(params);

如果自动对焦准备就绪，请调用相机拍摄照片（活动类别）：

public void butClick(View v){
    preview.camera.autoFocus(new AutoFocusCallback() {
        public void onAutoFocus(boolean success, Camera camera) {
            if(success){
                camera.takePicture(shutterCallback, rawCallback, jpegCallback);
            }
        }
    });
}

获取图片（活动类）：

PictureCallback jpegCallback = new PictureCallback() {
    public void onPictureTaken(byte[] data, Camera camera) {
        //do something
    }
};

Answer 4

看起来你应该continuous autofocus，如下所述。

您可以参考question here。

Answer 5

这适用于预览回调：

Camera.Parameters parameters = camera.getParameters();
if (parameters.getSupportedFocusModes().contains(
        Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO)) {
    parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
}
camera.setParameters(parameters);

Answer 6

你可以试试代码：

ShutterCallback _pfnShutterCallback = new ShutterCallback() {

        @Override
        public void onShutter() {
            // TODO Auto-generated method stub

        }

    };

    PictureCallback _pfnRawPictureCallback = new PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            // TODO Auto-generated method stub

        }
    };

    private AutoFocusCallback _pfnAutoFocusCallback = new AutoFocusCallback() {

        @Override
        public void onAutoFocus(boolean success, Camera camera) {
            // TODO Auto-generated method stub
            camera.autoFocus(null);
            camera.takePicture(_pfnShutterCallback, _pfnRawPictureCallback,
                    mPicture);

        }
    };
    private PictureCallback mPicture = new PictureCallback() {

        public void onPictureTaken(byte[] data, Camera camera) {
            new SavePhotoTask().execute(data);
            camera.startPreview();

        }
    };
class SavePhotoTask extends AsyncTask<byte[], String, String> {
// Process save file image
}

呼叫捕获：mCamera.autoFocus(autoFocusCallback);

您可以参考： http://android-er.blogspot.com/2011/01/start-camera-auto-focusing-autofocus.html

如何自动对焦Android相机？

6 个答案: