android 4.0 USB Camera范例(二)应用层

android 4.0 USB Camera实例(二)应用层

上一篇说了HAL层 这一篇具体应用HAL层 实例预览与拍照的功能

首先贴上两个主文件的源码

Fimcgzsd.java

package com.dao.usbcam;public class Fimcgzsd {	static public native int open(byte[] devname);	static public native int qbuf(int index);	static public native int streamon();	static public native int streamoff();	static public native int dqbuf(byte[] videodata);	static public native int release();	static public native int init(int width, int height,int numbuf);	static {		System.loadLibrary("fimcgzsd");	}}

这个主要是HAL层的一些接口函数

MainActivity.java

package com.dao.usbcam;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.os.Bundle;import android.os.Environment;import android.os.Handler;import android.text.format.Time;import android.view.Menu;import android.view.View;import android.view.Window;import android.view.WindowManager;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ImageView;import android.widget.Toast;public class MainActivity extends Activity {	private ImageView mImag;	private int width = 640;	private int height = 480;	private String devname = "/dev/video3";	private byte[] mdata;	private Handler mHandler;	private int numbuf = 0;	private int index = 0;	private int ret = 0;	public Button mcap;	private Bitmap bitmap;	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		requestWindowFeature(Window.FEATURE_NO_TITLE);		getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,		  WindowManager.LayoutParams.FLAG_FULLSCREEN);		setContentView(R.layout.activity_main);		mImag = (ImageView)findViewById(R.id.mimg);		mcap = (Button)findViewById(R.id.mcap);		numbuf  = 4;		mdata = new byte[width * height * numbuf];		ret = Fimcgzsd.open(devname.getBytes());		if(ret < 0)			finish();		ret = Fimcgzsd.init(width, height, numbuf);		if(ret < 0)			finish();		ret = Fimcgzsd.streamon();		if(ret < 0)			finish();		mHandler = new Handler();		new StartThread().start();		mcap.setOnClickListener(new CaptureListener());	}	final Runnable mUpdateUI = new Runnable() {		@Override		public void run() {			// TODO Auto-generated method stub			mImag.setImageBitmap(bitmap);		    		}	};		class StartThread extends Thread {		@Override		public void run() {			// TODO Auto-generated method stub			//super.run();			while(true) {				index = Fimcgzsd.dqbuf(mdata);				if(index < 0) {					onDestroy();					break;				}				mHandler.post(mUpdateUI);				bitmap = BitmapFactory.decodeByteArray(mdata, 0, width * height);				Fimcgzsd.qbuf(index);			}		}	}	public static void saveMyBitmap(Bitmap mBitmap) {    	Time mtime = new Time();    	mtime.setToNow();    	File fdir = new File(Environment.getExternalStorageDirectory().getPath() + "/DCIM/" + "/gzsd/");    	if(!fdir.exists()) {    		fdir.mkdir();    	}        File f = new File(Environment.getExternalStorageDirectory().getPath() + "/DCIM/" + "/gzsd/" + mtime.year + mtime.month + mtime.monthDay + mtime.hour + mtime.minute +mtime.second+".png");        try {                f.createNewFile();        } catch (IOException e) {        	e.printStackTrace();        }        FileOutputStream fOut = null;        try {                fOut = new FileOutputStream(f);                mBitmap.compress(Bitmap.CompressFormat.PNG, 100, fOut);                fOut.flush();                fOut.close();        } catch (FileNotFoundException e) {        	e.printStackTrace();        } catch (IOException e) {        	e.printStackTrace();        }    }	    class CaptureListener implements OnClickListener{		@Override		public void onClick(View v) {			// TODO Auto-generated method stub			//new CapThread().start();			//Fimcgzsd.streamoff();			saveMyBitmap(bitmap);			//Fimcgzsd.streamon();			Toast.makeText(MainActivity.this, "Capture Successfully", Toast.LENGTH_LONG).show();		}    	    }    	class CapThread extends Thread {		@Override		public void run() {			// TODO Auto-generated method stub			//super.run();			saveMyBitmap(bitmap);			Toast.makeText(MainActivity.this, "Capture Successfully", Toast.LENGTH_LONG).show();		}			}		@Override	protected void onStop() {		// TODO Auto-generated method stub		super.onStop();		Fimcgzsd.release();		finish();	}	@Override	protected void onPause() {		// TODO Auto-generated method stub		super.onPause();		Fimcgzsd.release();		finish();	}	@Override	protected void onDestroy() {		// TODO Auto-generated method stub		super.onDestroy();		Fimcgzsd.release();	}	@Override	public boolean onCreateOptionsMenu(Menu menu) {		// Inflate the menu; this adds items to the action bar if it is present.		getMenuInflater().inflate(R.menu.main, menu);		finish();		return true;	}}

整体过程 其实很简单

首先open

这里usb camera设备为/dev/video3 为了修改方面所以我把这个参数放在应用层里传到HAL层 分辨率为640*480

然后init

Fimcgzsd.init(width, height, numbuf);

传入宽，高 以及 缓冲帧的数目

然后开启视频流

Fimcgzsd.streamon();

开另外一个进程 循环获取数据 由于这里获取到的数据直接是jpeg格式的所以 我直接把他转成bmp然后用imageview直接显示 又省了不少事

贴上我的效果图

30W像素的摄像头，目前capture似乎还有问题，似乎是驱动有问题 继续研究中...