Android Camera API 1.0，2.0，3.0 知多少

Posted 2023-05-03

参考技术A 　　看到源码里面有诸如Camera.h , Camera2.h， Camera3.h的文件，觉得奇怪，后面在Camera3.h

　　中找到了对前后3个版本的概要性描述。

　　BTW， 我们看代码的过程中，如何避免不需要的文件被添加到工程？

　　我是指： 我只想看Camera3.0的代码，怎么去除掉其他版本的呢？

　　不知道各位是否知道这些牵涉到哪些文件？ 谢谢！！

　　* S1. Version history:
　　* 1.0: Initial android camera HAL (Android 4.0) [camera.h]:
　　*
　　* - Converted from C3;3; CameraHardwareInterface abstraction layer.
　　*
　　* - Supports android.hardware.Camera API.
　　*
　　* 2.0: Initial release of expanded-capability HAL (Android 4.2) [camera2.h]:
　　*
　　* - Sufficient for implementing existing android.hardware.Camera API.
　　*
　　* - Allows for ZSL queue in camera service layer
　　*
　　* - Not tested for any new features such manual capture control, Bayer RAW
　　* capture, reprocessing of RAW data.
　　* 3.0: First revision of expanded-capability HAL:
　　*
　　* - Major version change since the ABI is completely different. No change to
　　* the required hardware capabilities or operational model from 2.0.
　　*
　　* - Reworked input request and stream queue interfaces: Framework calls into
　　* HAL with next request and stream buffers already dequeued. Sync framework
　　* support is included, necessary for efficient implementations.
　　*
　　* - Moved triggers into requests, most notifications into results.
　　*
　　* - Consolidated all callbacks into framework into one structure, and all
　　* setup methods into a single initialize() call.
　　* - Made stream configuration into a single call to simplify stream
　　* management. Bidirectional streams replace STREAM_FROM_STREAM construct.本回答被提问者和网友采纳

Android 音视频开发：使用 Camera API 采集视频数据

本文主要将的是：使用 Camera API 采集视频数据并保存到文件，分别使用 SurfaceView、TextureView 来预览 Camera 数据，取到 NV21 的数据回调。

注： 需要权限：<uses-permission android:name="android.permission.CAMERA" />

一、预览 Camera 数据

做过Android开发的人一般都知道，有两种方法能够做到这一点：SurfaceView、TextureView。

下面是使用SurfaceView预览数据的方式：

SurfaceView surfaceView;
Camera camera;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    surfaceView = (SurfaceView) findViewById(R.id.surface_view);
    surfaceView.getHolder().addCallback(this);

    // 打开摄像头并将展示方向旋转90度
    camera = Camera.open();
    camera.setDisplayOrientation(90);

}

//------ Surface 预览 -------
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
    try {
        camera.setPreviewDisplay(surfaceHolder);
        camera.startPreview();
    } catch (IOException e) {
        e.printStackTrace();
    }
}


@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int format, int w, int h) {

}

@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
    camera.release();
}

下面是使用TextureView预览数据的方式：

    TextureView textureView;
    Camera camera;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textureView = (TextureView) findViewById(R.id.texture_view);
        textureView.setSurfaceTextureListener(this);// 打开摄像头并将展示方向旋转90度
        camera = Camera.open();
        camera.setDisplayOrientation(90);
    }
//------ Texture 预览 -------
    @Override
    public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int i, int i1) {
        try {
            camera.setPreviewTexture(surfaceTexture);
            camera.startPreview();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int i, int i1) {

    }

    @Override
    public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
        camera.release();
        return false;
    }

    @Override
    public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {

    }