基于Android TextureView与SurfaceTexture实现相机Camera拍照预览与保存照片

向右看齐 2023-10-17 15:48 72阅读 0赞

**基于Android TextureView与SurfaceTexture实现相机Camera拍照预览与保存照片**

写一个简单的例子，实现一个常见的开发功能：拍照功能。  
技术路线：通过TextureView的通道获取SurfaceTexture作为相机的预览，然后通过Camera的take方法把相机抓取的byte字节数据转换为Bitmap，然后存放到手机的存储器上，至此，一个最简单的拍照功能完成。  
注意，本例如果运行在Android高版本（6.0+，7.0+或更高），需要多写运行时权限申请代码。本例出于功能演示，不再冗余的写这部分代码。只给出最骨干的关键代码逻辑。

布局文件activity\_main.xml：

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/holo_blue_light"
        tools:context="zhangphil.view.MainActivity">
    
        <zhangphil.view.MyTextureView
            android:id="@+id/textureView"
            android:layout_width="300dp"
            android:layout_height="200dp"
            android:layout_centerInParent="true" />
    
        <Button
            android:id="@+id/capture"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_centerHorizontal="true"
            android:text="拍摄" />
    </RelativeLayout>

MyTextureView.java：

package zhangphil.view;
    
    import android.content.Context;
    import android.graphics.Bitmap;
    import android.graphics.BitmapFactory;
    import android.graphics.SurfaceTexture;
    import android.hardware.Camera;
    import android.os.Environment;
    import android.util.AttributeSet;
    import android.util.Log;
    import android.view.TextureView;
    
    import java.io.BufferedOutputStream;
    import java.io.File;
    import java.io.FileOutputStream;
    
    /**
     * Created by Phil on 2017/9/13.
     */
    
    public class MyTextureView extends TextureView {
        public Camera mCamera;
    
        public MyTextureView(Context context, AttributeSet attrs) {
            super(context, attrs);
            init();
        }
    
        private void init() {
            mCamera = Camera.open();
    
            this.setSurfaceTextureListener(new SurfaceTextureListener() {
    
                @Override
                public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int width, int height) {
                    try {
                        mCamera.setPreviewTexture(surfaceTexture);
                        mCamera.startPreview();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
    
                @Override
                public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int width, int height) {
    
                }
    
                @Override
                public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
                    mCamera.stopPreview();
                    mCamera.release();
                    mCamera = null;
    
                    return true;
                }
    
                @Override
                public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {
    
                }
            });
        }
    
        public void take() {
            if(mCamera!=null)
                mCamera.takePicture(null, null, mPictureCallback);
        }
    
        Camera.PictureCallback mPictureCallback = new Camera.PictureCallback() {
            @Override
            public void onPictureTaken(byte[] data, Camera camera) {
                mCamera.stopPreview();
                new FileSaver(data).save();
            }
        };
    
        private class FileSaver implements Runnable {
            private byte[] buffer;
    
            public FileSaver(byte[] buffer) {
                this.buffer = buffer;
            }
    
            public void save() {
                new Thread(this).start();
            }
    
            @Override
            public void run() {
                try {
                    File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "zhangphil.png");
                    file.createNewFile();
    
                    FileOutputStream os = new FileOutputStream(file);
                    BufferedOutputStream bos = new BufferedOutputStream(os);
    
                    Bitmap bitmap = BitmapFactory.decodeByteArray(buffer, 0, buffer.length);
                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, bos);
    
                    bos.flush();
                    bos.close();
                    os.close();
    
                    Log.d("照片已保存", file.getAbsolutePath());
    
                    mCamera.startPreview();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

MainActivity.java：

package zhangphil.view;
    
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.View;
    
    public class MainActivity extends AppCompatActivity {
        private MyTextureView textureView;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            textureView = (MyTextureView) findViewById(R.id.textureView);
            findViewById(R.id.capture).setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    textureView.take();
                }
            });
        }
    }

权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
        <uses-permission android:name="android.permission.CAMERA"/>

代码运行结果：

![Center][]

[Center]: https://img-blog.csdn.net/20170914101607175?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvemhhbmdwaGls/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center