对于我的大学论文，我需要一个可以实时检测和识别面部的android程序。我读过关于“android-vision＆＃39;库并测试了示例代码。
修改后的代码：
package com.google.android.gms.samples.vision.face.facetracker;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.AsyncTask;
import android.os.Environment;
import android.util.Log;
import android.widget.Toast;
import com.google.android.gms.samples.vision.face.facetracker.ui.camera.GraphicOverlay;
import com.google.android.gms.vision.face.Face;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.net.Socket;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* Graphic instance for rendering face position, orientation, and landmarks within an associated
* graphic overlay view.
*/
class FaceGraphic extends GraphicOverlay.Graphic
{
private static final float FACE_POSITION_RADIUS = 10.0f;
private static final float ID_TEXT_SIZE = 40.0f;
private static final float ID_Y_OFFSET = 50.0f;
private static final float ID_X_OFFSET = -50.0f;
private static final float BOX_STROKE_WIDTH = 5.0f;
public Canvas canvas1;
public Face face;
int i =0;
int flag = 0;
private static final int COLOR_CHOICES[] = {
Color.BLUE,
Color.CYAN,
Color.GREEN,
Color.MAGENTA,
Color.RED,
Color.WHITE,
Color.YELLOW
};
private static int mCurrentColorIndex = 0;
private Paint mFacePositionPaint;
private Paint mIdPaint;
private Paint mBoxPaint;
private volatile Face mFace;
private int mFaceId;
private float mFaceHappiness;
public Bitmap myBitmap ;
FaceGraphic(GraphicOverlay overlay)
{
super(overlay);
mCurrentColorIndex = (mCurrentColorIndex + 1) % COLOR_CHOICES.length;
final int selectedColor = COLOR_CHOICES[mCurrentColorIndex];
mFacePositionPaint = new Paint();
mFacePositionPaint.setColor(selectedColor);
mIdPaint = new Paint();
mIdPaint.setColor(selectedColor);
mIdPaint.setTextSize(ID_TEXT_SIZE);
mBoxPaint = new Paint();
mBoxPaint.setColor(selectedColor);
mBoxPaint.setStyle(Paint.Style.STROKE);
mBoxPaint.setStrokeWidth(BOX_STROKE_WIDTH);
}
void setId(int id)
{
mFaceId = id;
flag = 1;
}
/**
* Updates the face instance from the detection of the most recent frame. Invalidates the
* relevant portions of the overlay to trigger a redraw.
*/
void updateFace(Face face)
{
mFace = face;
postInvalidate();
}
/**
* Draws the face annotations for position on the supplied canvas.
*/
@Override
public void draw(Canvas canvas)
{
face = mFace;
if (face == null)
{
return;
}
// Draws a circle at the position of the detected face, with the face's track id below.
float x = translateX(face.getPosition().x + face.getWidth() / 2);
float y = translateY(face.getPosition().y + face.getHeight() / 2);
// canvas.drawCircle(x, y, FACE_POSITION_RADIUS, mFacePositionPaint);
canvas.drawText("id: " + mFaceId, x + ID_X_OFFSET, y + ID_Y_OFFSET, mIdPaint);
// canvas.drawText("happiness: " + String.format("%.2f", face.getIsSmilingProbability()), x - ID_X_OFFSET, y - ID_Y_OFFSET, mIdPaint);
// canvas.drawText("right eye: " + String.format("%.2f", face.getIsRightEyeOpenProbability()), x + ID_X_OFFSET * 2, y + ID_Y_OFFSET * 2, mIdPaint);
// canvas.drawText("left eye: " + String.format("%.2f", face.getIsLeftEyeOpenProbability()), x - ID_X_OFFSET*2, y - ID_Y_OFFSET*2, mIdPaint);
// Draws a bounding box around the face.
float xOffset = scaleX(face.getWidth() / 2.0f);
float yOffset = scaleY(face.getHeight() / 2.0f);
float left = x - xOffset;
float top = y - yOffset;
float right = x + xOffset;
float bottom = y + yOffset;
canvas.drawRect(left, top, right, bottom, mBoxPaint);
Log.d("MyTag", "hello "+i);
i++;
if (flag == 1)
{
flag = 0;
canvas1=canvas;
// send face image to server for recognition
new MyAsyncTask().execute("ppppp");
}
}
class MyAsyncTask extends AsyncTask<String, Void, String>
{
private Context context;
public MyAsyncTask()
{
// TODO Auto-generated constructor stub
//context = applicationContext;
}
protected String doInBackground(String... params)
{
try
{
Log.d("MyTag", "face.getWidth() "+face.getWidth());
Bitmap temp_bitmap = Bitmap.createBitmap((int)face.getWidth(), (int)face.getHeight(), Bitmap.Config.RGB_565);
canvas1.setBitmap(temp_bitmap);
}
catch (Exception e)
{
Log.e("MyTag", "I got an error", e);
e.printStackTrace();
}
Log.d("MyTag", "doInBackground");
return null;
}
protected void onPostExecute(String result) {
Log.d("MyTag", "onPostExecute " + result);
// tv2.setText(s);
}
}
}
它给了我这个错误：
12-16 03:08:00.310 22926-23044/com.google.android.gms.samples.vision.face.facetracker E/MyTag: I got an error
java.lang.UnsupportedOperationException
at android.view.HardwareCanvas.setBitmap(HardwareCanvas.java:39)
at com.google.android.gms.samples.vision.face.facetracker.FaceGraphic$MyAsyncTask.doInBackground(FaceGraphic.java:175)
at com.google.android.gms.samples.vision.face.facetracker.FaceGraphic$MyAsyncTask.doInBackground(FaceGraphic.java:158)
此代码可以实时检测面部。对于识别部分，我打算使用JavaCV＆＃39; https://github.com/bytedeco/javacv。如果我可以在位图中捕获面部，那么我可以将其保存在.jpg图像中然后我就可以识别它。你能不能给我一些建议，如何保存检测到的脸。谢谢。
答案 0 :(得分：0)
TL; DR：捕获一个Frame，对其进行处理，然后保存/导出。
@Override
public void setBitmap(Bitmap bitmap) {
throw new UnsupportedOperationException();
}
这意味着Canvas无法处理setBitmap(Bitmap bitmap)方法
您的执行情况有几个问题。
首先：加载了AsynkTask，其中许多是无用/冗余的
如果您使用的是com.google.android.gms.vision.*类，则每秒可能会收到约30个事件。当发生事件时，几乎可以确保所捕获的帧与所评估的帧不同。 You are racing against your conditions。
第二：使用画布设置位图
在使用类时，请始终检查其文档和祖先，最后是其实现。
ImageView将按照您的期望执行。通过接收位图，然后对其进行设置。所有竞争条件将由OS <处理，而多余的请求将由Main Looper
丢弃最后
如果您需要的是“拍照，当有人闭着眼睛微笑时”，那么您需要颠倒您的逻辑。使用源生成框架。然后处理框架，如果框架符合您的条件，请保存它。
This codelabs project does almost what you want，它很好地解释了其详细信息