android-拍照

package com.example.android_camera;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Toast;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class MainActivity extends AppCompatActivity {

private SurfaceView sv_main_surface;
private Camera camera;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sv_main_surface = (SurfaceView) findViewById(R.id.sv_main_surface);

sv_main_surface.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder surfaceHolder) {
//打开照相机
camera = Camera.open();
//设置参数
Camera.Parameters parameters=camera.getParameters();

parameters.setPictureFormat(PixelFormat.JPEG);

parameters.set("jpeg-quality",85);

camera.setParameters(parameters);

//将画面展示到surfaceView
try {
camera.setPreviewDisplay(sv_main_surface.getHolder());
} catch (IOException e) {
e.printStackTrace();
}

//开启预览效果
camera.startPreview();
}

@Override
public void surfaceChanged(SurfaceHolder surfaceHolder, int i, int i1, int i2) {

}

@Override
public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
if(camera!=null){
camera.stopPreview();
camera.release();
camera=null;
}
}
});

}

public void takePhoto(View view){
camera.takePicture(null, null, new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] bytes, Camera camera) {
//技术：图片压缩技术

Bitmap bitmap=BitmapFactory.decodeByteArray(bytes,0,bytes.length);

try {
FileOutputStream fos=new FileOutputStream("/mnt/sdcard/6666"+System.currentTimeMillis()+".png");
bitmap.compress(Bitmap.CompressFormat.PNG,85,fos);

camera.stopPreview();
camera.startPreview();
} catch (FileNotFoundException e) {
e.printStackTrace();
}

}
});
}
}

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