如何从 Surface View 获取位图

Posted 2023-04-17

【中文标题】如何从 Surface View 获取位图

【英文标题】：How to get bitmap from Surface View

【发布时间】：2021-06-29 15:54:31

【问题描述】：

我正在尝试从我的表面视图中获取位图。我已经在这个论坛和几乎所有论坛上看到了很多答案。我正在使用 ViewGroup 的自定义类，其中我使用表面视图来预览相机图像和图形叠加。

这是我的 CameraSourcePreview.class

import android.content.Context;
import android.content.res.Configuration;
import android.graphics.SurfaceTexture;
import android.support.v7.util.AsyncListUtil;
import android.util.AttributeSet;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.TextureView;
import android.view.View;
import android.view.ViewGroup;

import com.google.android.gms.common.images.Size;
import com.google.android.gms.vision.CameraSource;

import java.io.IOException;

public class CameraSourcePreview extends ViewGroup 
    private static final String TAG = "CameraSourcePreview";

    private Context mContext;
    private SurfaceView mSurfaceView;
    private boolean mStartRequested;
    private boolean mSurfaceAvailable;
    private CameraSource mCameraSource;

    private GraphicOverlay mOverlay;

    public CameraSourcePreview(Context context, AttributeSet attrs) 
        super(context, attrs);
        mContext = context;
        mStartRequested = false;
        mSurfaceAvailable = false;

        mSurfaceView = new SurfaceView(context);
        mSurfaceView.getHolder().addCallback(new SurfaceCallback());
        addView(mSurfaceView);
    

    public void start(CameraSource cameraSource) throws IOException 
        if (cameraSource == null) 
            stop();
        

        mCameraSource = cameraSource;

        if (mCameraSource != null) 
            mStartRequested = true;
            startIfReady();
        
    

    public void start(CameraSource cameraSource, GraphicOverlay overlay) throws IOException 
        mOverlay = overlay;
        start(cameraSource);
    

    public void stop() 
        if (mCameraSource != null) 
            mCameraSource.stop();
        
    

    public void release() 
        if (mCameraSource != null) 
            mCameraSource.release();
            mCameraSource = null;
        
    

    private void startIfReady() throws IOException 
        if (mStartRequested && mSurfaceAvailable) 
            mCameraSource.start(mSurfaceView.getHolder());
            if (mOverlay != null) 
                Size size = mCameraSource.getPreviewSize();
                int min = Math.min(size.getWidth(), size.getHeight());
                int max = Math.max(size.getWidth(), size.getHeight());
                if (isPortraitMode()) 
                    // Swap width and height sizes when in portrait, since it will be rotated by
                    // 90 degrees
                    mOverlay.setCameraInfo(min, max, mCameraSource.getCameraFacing());
                 else 
                    mOverlay.setCameraInfo(max, min, mCameraSource.getCameraFacing());
                
                mOverlay.clear();
            
            mStartRequested = false;
        
    

    private class SurfaceCallback implements SurfaceHolder.Callback 
        @Override
        public void surfaceCreated(SurfaceHolder surface) 
            mSurfaceAvailable = true;
            try 
                startIfReady();
             catch (IOException e) 
                Log.e(TAG, "Could not start camera source.", e);
            
        

        @Override
        public void surfaceDestroyed(SurfaceHolder surface) 
            mSurfaceAvailable = false;
        

        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) 
        
    

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) 
        int width = 320;
        int height = 240;
        if (mCameraSource != null) 
            Size size = mCameraSource.getPreviewSize();
            if (size != null) 
                width = size.getWidth();
                height = size.getHeight();
            
        

        // Swap width and height sizes when in portrait, since it will be rotated 90 degrees
        if (isPortraitMode()) 
            int tmp = width;
            width = height;
            height = tmp;
        

        final int layoutWidth = right - left;
        final int layoutHeight = bottom - top;

        // Computes height and width for potentially doing fit width.
        int childWidth = layoutWidth;
        int childHeight = layoutHeight;
                //(int)(((float) layoutWidth / (float) width) * height);
/*
        // If height is too tall using fit width, does fit height instead.
        if (childHeight > layoutHeight) 
            childHeight = layoutHeight;
            childWidth = (int)(((float) layoutHeight / (float) height) * width);
        */

        for (int i = 0; i < getChildCount(); ++i) 
            getChildAt(i).layout(0, 0, childWidth, childHeight);
        

        try 
            startIfReady();
         catch (IOException e) 
            Log.e(TAG, "Could not start camera source.", e);
        
    

    private boolean isPortraitMode() 
        int orientation = mContext.getResources().getConfiguration().orientation;
        if (orientation == Configuration.ORIENTATION_LANDSCAPE) 
            return false;
        
        if (orientation == Configuration.ORIENTATION_PORTRAIT) 
            return true;
        

        Log.d(TAG, "isPortraitMode returning false by default");
        return false;
    

现在，当我从 CameraSource 捕捉图像时，它会捕捉图像，但不会捕捉我在表面视图上膨胀的图形叠加层。表面视图也不允许我从中获取位图。如果我尝试获取根视图的屏幕截图，则它仅捕获图形叠加而不是表面视图图像。

我的应用程序正在处理面部过滤器 github 项目的逻辑（将根据要求提供链接） 我基本上被卡住了，因为我想同时捕获两者。

【参考方案1】：

您必须截取特定的视图屏幕截图，例如以这种方式将任何视图转换为位图

How to convert Views to bitmaps?

【讨论】：

我尝试截取表面视图。但它只捕获图形覆盖而不是人的图片。