1、在Activity界面代码中：
private var mCamera: Camera? = null
private val mWidth = GwApplication.DEFAULT_REMOTE_WIDTH_EXT
private val mHeight = GwApplication.DEFAULT_REMOTE_HEIGHT_EXT
private var imgData: ImageData = ImageData(mWidth, mHeight)

/**
 * Camera初始化
 **/
private fun initCameara() {
    //log("====initCameara()")
    try {
        mCamera = Camera.open(GwApplication.DEFAULT_CR_CAMERA)
        val params = mCamera!!.getParameters()
        params.previewFormat = ImageFormat.NV21
        params.setPreviewSize(mWidth, mHeight)
        //params.pictureFormat = ImageFormat.NV21
        params.setPictureSize(mWidth, mHeight)
        //params.zoom = 0
        //params.setRotation(0)
        params.setPreviewFpsRange(10, 15)
        mCamera!!.setParameters(params)
    } catch (ex: RuntimeException) {
        ex.printStackTrace()
    }
}

/**
 * 开始监听回调，设置预览
 **/
private fun setCallback() {
    //log("====setCallback()")
    try {
        // 主要是surfaceTexture获取预览数据，但不显示
        val surfaceTexture = SurfaceTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES)
        mCamera!!.setPreviewTexture(surfaceTexture)
    } catch (e: IOException) {
        e.printStackTrace()
    }
    // 设置 mCamera.addCallbackBuffer(mPreviewData) 后才会回调，旨在每处理完一帧数据回调一次
    mCamera!!.setPreviewCallbackWithBuffer(mPreviewCallback)
    mCamera!!.addCallbackBuffer(imgData.data)
    mCamera!!.startPreview()
}

/**
 * 帧数据监听实现
**/
private val mPreviewCallback =
    android.hardware.Camera.PreviewCallback { data, camera -> // 在此处处理当前帧数据，并设置下一帧回调
        //log("====PreviewCallback()")
        imgData.setTempData(data)
        mCamera!!.addCallbackBuffer(imgData.data)
        //        if (isShow) {
        //            showPic(imgData.previewData)
        //        }
    }

/**
 * 关闭相机
**/
private fun closeCamera() {
    mCamera!!.stopPreview()
    mCamera!!.setPreviewCallbackWithBuffer(null)
    mCamera!!.release()
    mCamera = null
}

/**
 * 显示图片
 **/
private fun showPic(data: ByteArray) {
    val time = System.currentTimeMillis()
    try {
        val image = YuvImage(data, ImageFormat.NV21, mWidth, mHeight, null)
        if (image != null) {
            val stream = ByteArrayOutputStream()
            image.compressToJpeg(Rect(0, 0, mWidth, mHeight), 80, stream)
            runOnUiThread {
                val curTime = System.currentTimeMillis()
                ivCamera.setImageBitmap(null)
                releaseBitmap()
                mBitmap = BitmapFactory.decodeByteArray(stream.toByteArray(), 0, stream.size())//fastYUVtoRGB!!.convertYUVtoRGB(data, mWidth, mHeight)
                stream.close()
                ivCamera.setImageBitmap(mBitmap)
                ivCamera.invalidate()
            }
        }
    } catch (e: Exception) {
    }
}

private fun releaseBitmap() {
    if(mBitmap != null) {
        if(!mBitmap!!.isRecycled) {
            mBitmap!!.recycle()
        }
        mBitmap = null
    }
}

2、屏幕和视频图像的效果图：

其他依赖代码：
ImageData.java文件

/**

• author zoufeng

• date:2021/10/15

• desc:
  */
  public class ImageData {
  private int width;
  private int height;
  private int size;
  private byte[] data;
  private byte[] temp;
  private Boolean isNew;

  public ImageData(int width, int height) {
  this.width = width;
  this.height = height;
  size = width * height * 3 / 2;
  data = new byte[size];
  temp = new byte[size];
  isNew = true;
  }

  public int getWidth() {
  return width;
  }

  public int getHeight() {
  return height;
  }

  public byte[] getData() {
  return data;
  }

  public void setTempData(byte[] preData) {
  synchronized (isNew) {
  if(!isNew) {
  System.arraycopy(preData, 0, temp, 0, preData.length);
  isNew = true;
  }
  }
  }

  public byte[] getTempData() {
  return temp;
  }

  public boolean isNew() {
  return isNew;
  }

  public void setNew(boolean isNew) {
  synchronized (this.isNew) {
  this.isNew = isNew;
  }
  }
  }

FastYUVtoRGB.java文件：（用于YUV直接转换成Bitmap，速度比较快，图像转换在4毫秒一下。）

/**

• author zoufeng
• date:2021/11/17
• desc:
  */
  import android.content.Context;
  import android.graphics.Bitmap;
  import android.graphics.Canvas;
  import android.graphics.Matrix;
  import android.renderscript.Allocation;
  import android.renderscript.Element;
  import android.renderscript.RenderScript;
  import android.renderscript.ScriptIntrinsicYuvToRGB;
  import android.renderscript.Type;

/**

• 使用RenderScript将视频YUV流转换为BMP

• 注：这个类适用于CameraPreview不变的情况
  */
  public class FastYUVtoRGB {
  private RenderScript rs;
  private ScriptIntrinsicYuvToRGB yuvToRgbIntrinsic;
  private Type.Builder yuvType, rgbaType;
  private Allocation in, out;

  public FastYUVtoRGB(Context context) {
  rs = RenderScript.create(context);
  yuvToRgbIntrinsic = ScriptIntrinsicYuvToRGB.create(rs, Element.U8_4(rs));
  }

  public Bitmap convertYUVtoRGB(byte[] yuvData, int width, int height) {
  if (yuvType == null) {
  yuvType = new Type.Builder(rs, Element.U8(rs)).setX(yuvData.length);
  in = Allocation.createTyped(rs, yuvType.create(), Allocation.USAGE_SCRIPT);

       rgbaType = new Type.Builder(rs, Element.RGBA_8888(rs)).setX(width).setY(height);
       out = Allocation.createTyped(rs, rgbaType.create(), Allocation.USAGE_SCRIPT);
   }
   in.copyFrom(yuvData);
   yuvToRgbIntrinsic.setInput(in);
   yuvToRgbIntrinsic.forEach(out);
   Bitmap bmpout = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
   out.copyTo(bmpout);
   return bmpout;
  

  }

  /**

  • Returns a transformation matrix from one reference frame into another.

  • Handles cropping (if maintaining aspect ratio is desired) and rotation.

  • @param srcWidth Width of source frame.

  • @param srcHeight Height of source frame.

  • @param dstWidth Width of destination frame.

  • @param dstHeight Height of destination frame.

  • @param applyRotation Amount of rotation to apply from one frame to another.

  •                        Must be a multiple of 90.
    

  • @param flipHorizontal should flip horizontally

  • @param flipVertical should flip vertically

  • @param maintainAspectRatio If true, will ensure that scaling in x and y remains constant,

  •                        cropping the image if necessary.
    

  • @return The transformation fulfilling the desired requirements.
    */
    public static Matrix getTransformationMatrix(
    final int srcWidth,
    final int srcHeight,
    final int dstWidth,
    final int dstHeight,
    final int applyRotation, boolean flipHorizontal, boolean flipVertical,
    final boolean maintainAspectRatio) {
    final Matrix matrix = new Matrix();

    if (applyRotation != 0) {
    if (applyRotation % 90 != 0) {
    throw new IllegalArgumentException(String.format(“Rotation of %d % 90 != 0”, applyRotation));
    }

     // Translate so center of image is at origin.
     matrix.postTranslate(-srcWidth / 2.0f, -srcHeight / 2.0f);
    
     // Rotate around origin.
     matrix.postRotate(applyRotation);
    

    }

    // Account for the already applied rotation, if any, and then determine how
    // much scaling is needed for each axis.
    final boolean transpose = (Math.abs(applyRotation) + 90) % 180 == 0;

    final int inWidth = transpose ? srcHeight : srcWidth;
    final int inHeight = transpose ? srcWidth : srcHeight;

    int flipHorizontalFactor = flipHorizontal ? -1 : 1;
    int flipVerticalFactor = flipVertical ? -1 : 1;

    // Apply scaling if necessary.
    if (inWidth != dstWidth || inHeight != dstHeight) {
    final float scaleFactorX = flipHorizontalFactor * dstWidth / (float) inWidth;
    final float scaleFactorY = flipVerticalFactor * dstHeight / (float) inHeight;

     if (maintainAspectRatio) {
         // Scale by minimum factor so that dst is filled completely while
         // maintaining the aspect ratio. Some image may fall off the edge.
         final float scaleFactor = Math.max(Math.abs(scaleFactorX), Math.abs(scaleFactorY));
         matrix.postScale(scaleFactor, scaleFactor);
     } else {
         // Scale exactly to fill dst from src.
         matrix.postScale(scaleFactorX, scaleFactorY);
     }
    

    }

    if (applyRotation != 0) {
    // Translate back from origin centered reference to destination frame.
    float dx = dstWidth / 2.0f;
    float dy = dstHeight / 2.0f;
    matrix.postTranslate(dx, dy);
    // postScale中心点如果出错，图像不会被变换
    matrix.postScale(flipHorizontalFactor, flipVerticalFactor, dx, dy);
    }

    return matrix;
    }

  /*
  /*
  example
  final Canvas canvas = new Canvas(out);
  // 这里的空白bitmap尺寸需要与变换后的预期尺寸一致
  Bitmap src = Bitmap.createBitmap(height, width, Bitmap.Config.ARGB_8888);
  Matrix transformation = getTransformationMatrix(src.getWidth(), src.getHeight(), targetWidth, targetHeight, rotation,true,false, true);
  canvas.drawBitmap(src, transformation, null);
  */
  }