写一个可以拍摄raw图并可以直接获取它的预览流的camera app,包括xml和注释
时间: 2024-03-17 10:46:41 浏览: 19
好的,以下是一个可以拍摄raw图并可以直接获取预览流的camera app的主要代码以及相应的注释:
1. 首先,在AndroidManifest.xml文件中添加以下权限:
```xml
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
```
2. 在布局文件中添加SurfaceView用于实时预览相机:
```xml
<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
```
3. 在Activity中初始化相机和SurfaceView:
```java
public class CameraActivity extends AppCompatActivity implements SurfaceHolder.Callback {
private Camera camera;
private SurfaceView surfaceView;
private SurfaceHolder surfaceHolder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera);
// 初始化SurfaceView
surfaceView = findViewById(R.id.surfaceView);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
}
}
```
4. 实现SurfaceHolder.Callback接口,重写surfaceCreated、surfaceChanged和surfaceDestroyed方法:
```java
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
// 初始化相机
camera = Camera.open();
try {
// 设置预览显示的Surface
camera.setPreviewDisplay(surfaceHolder);
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int i, int i1, int i2) {
// 开始预览
camera.startPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
// 释放相机资源
camera.stopPreview();
camera.release();
}
```
5. 添加拍照按钮,设置拍照监听器:
```java
public void takePicture(View view) {
// 设置拍照回调
camera.takePicture(null, null, new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] bytes, Camera camera) {
// 保存raw图像到SD卡
String fileName = "raw_" + System.currentTimeMillis() + ".dng";
File file = new File(Environment.getExternalStorageDirectory(), fileName);
try {
FileOutputStream fos = new FileOutputStream(file);
fos.write(bytes);
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
// 将raw图像转换为Bitmap并显示
Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
ImageView imageView = findViewById(R.id.imageView);
imageView.setImageBitmap(bitmap);
}
});
}
```
6. 在AndroidManifest.xml文件中添加以下特性,以支持拍摄raw图像:
```xml
<uses-feature android:name="android.hardware.camera2.full" />
<uses-feature android:name="android.hardware.camera.raw" />
```
以上就是一个可以拍摄raw图并可以直接获取预览流的camera app的主要代码以及注释。