使用的是android的uvccamera库写一个使用AppCompatImageView控件显示摄像头实时图像的例子
时间: 2024-02-23 21:58:30 浏览: 78
好的,以下是使用android的uvccamera库写一个使用AppCompatImageView控件显示摄像头实时图像的例子的步骤:
1. 在build.gradle文件中添加依赖:
```
implementation 'com.github.saki4510t:UVCCamera:2.5.9'
```
2. 在AndroidManifest.xml文件中添加权限:
```
<uses-feature android:name="android.hardware.usb.host" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />
```
3. 在Activity中声明以下变量:
```
private UVCCamera mUVCCamera;
private SurfaceView mSurfaceView;
private SurfaceHolder mSurfaceHolder;
private AppCompatImageView mImageView;
```
4. 在onCreate()方法中初始化SurfaceView、SurfaceHolder和UVCCamera:
```
mSurfaceView = findViewById(R.id.surface_view);
mSurfaceHolder = mSurfaceView.getHolder();
mSurfaceHolder.addCallback(mSurfaceHolderCallback);
mUVCCamera = new UVCCamera();
mUVCCamera.setDefaultPreviewSize(640, 480);
mUVCCamera.setPreviewDisplay(mSurfaceHolder);
mUVCCamera.setPreviewCallback(mPreviewCallback);
mUVCCamera.startPreview();
```
5. 在onCreate()方法中初始化AppCompatImageView:
```
mImageView = findViewById(R.id.image_view);
```
6. 在SurfaceHolder.Callback中实现SurfaceView的大小改变后重新设置UVCCamera的预览大小:
```
private final SurfaceHolder.Callback mSurfaceHolderCallback = new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
mUVCCamera.setDefaultPreviewSize(640, 480);
mUVCCamera.setPreviewDisplay(holder);
mUVCCamera.startPreview();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
mUVCCamera.setPreviewSize(width, height);
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
mUVCCamera.stopPreview();
mUVCCamera.release();
}
};
```
7. 在UVCCamera.PreviewCallback中实现从UVCCamera获取图像数据并显示在AppCompatImageView中:
```
private final UVCCamera.PreviewCallback mPreviewCallback = new UVCCamera.PreviewCallback() {
@Override
public void onPreviewFrame(byte[] data, UVCCamera camera) {
YuvImage yuvImage = new YuvImage(data, ImageFormat.NV21, mUVCCamera.getPreviewSize().width, mUVCCamera.getPreviewSize().height, null);
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
yuvImage.compressToJpeg(new Rect(0, 0, mUVCCamera.getPreviewSize().width, mUVCCamera.getPreviewSize().height), 80, byteArrayOutputStream);
byte[] jpegData = byteArrayOutputStream.toByteArray();
Bitmap bitmap = BitmapFactory.decodeByteArray(jpegData, 0, jpegData.length);
runOnUiThread(() -> {
mImageView.setImageBitmap(bitmap);
});
}
};
```
注意:以上代码仅供参考,应根据具体情况进行修改和完善。
阅读全文