android实现简单拍照功能

时间:2021-05-20

拍照可以调用系统的相机进行拍照,拍完保存到相应的SD卡目录。最近要用到拍照这个功能,首先试了下调用相机拍照,保存到相应目录,然后用imageview显示的时候感觉,很模糊。可能是图片被压缩的太狠了。所以自己使用Camera写了一个拍照的功能,拍出来的还挺清晰的,不过文件有点大一张图片差不多1.7M。如果想拍高清图可以使用下面的代码。

代码很简单,我就不做过多解释了。

package com.example.testsimple; import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.util.Date; import android.os.AsyncTask;import android.os.Bundle;import android.os.Environment;import android.app.Activity;import android.content.Intent;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.PixelFormat;import android.hardware.Camera;import android.text.format.DateFormat;import android.util.Log;import android.view.KeyEvent;import android.view.Menu;import android.view.SurfaceHolder;import android.view.SurfaceView;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ImageView; public class MainActivity extends Activity { private SurfaceView surfaceView; private SurfaceHolder surfaceHolder; private Camera camera; private File picture; private Button btnSave; private final static String TAG = "CameraActivity"; private ImageView open_picIcon; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); setupViews(); } private void setupViews(){ surfaceView = (SurfaceView) findViewById(R.id.camera_preview); // Camera interface to instantiate components surfaceHolder = surfaceView.getHolder(); // Camera interface to instantiate components surfaceHolder.addCallback(surfaceCallback); // Add a callback for the SurfaceHolder surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); btnSave = (Button) findViewById(R.id.save_pic); open_picIcon=(ImageView) findViewById(R.id.open_picIcon); btnSave.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { surfaceView.setVisibility(View.VISIBLE); open_picIcon.setVisibility(View.GONE); takePic(); } }); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_CAMERA || keyCode == KeyEvent.KEYCODE_SEARCH) { takePic(); return true; } return super.onKeyDown(keyCode, event); } private void takePic() { camera.stopPreview();// stop the preview camera.takePicture(null, null, pictureCallback); // picture } // Photo call back Camera.PictureCallback pictureCallback = new Camera.PictureCallback() { //@Override public void onPictureTaken(byte[] data, Camera camera) { new SavePictureTask().execute(data); camera.startPreview(); } }; // save pic class SavePictureTask extends AsyncTask<byte[], String, String> { @Override protected String doInBackground(byte[]... params) { String fname = DateFormat.format("yyyyMMddhhmmss", new Date()).toString()+".jpg"; Log.i(TAG, "fname="+fname+";dir="+Environment.getExternalStorageDirectory()); //picture = new File(Environment.getExternalStorageDirectory(),fname);// create file picture = new File(Environment.getExternalStorageDirectory()+"/images/"+fname); File file= picture.getParentFile(); if(!file.exists()) file.mkdir(); try { FileOutputStream fos = new FileOutputStream(picture.getPath()); // Get file output stream fos.write(params[0]); // Written to the file fos.close(); } catch (Exception e) { e.printStackTrace(); } return null; } @Override protected void onPostExecute(String result) { // TODO Auto-generated method stub super.onPostExecute(result); Bitmap bitmap=getDiskBitmap(picture.getPath()); surfaceView.setVisibility(View.GONE); open_picIcon.setVisibility(View.VISIBLE); open_picIcon.setImageBitmap(bitmap); } } private Bitmap getDiskBitmap(String pathString) { Bitmap bitmap = null; try { File file = new File(pathString); if(file.exists()) { bitmap = BitmapFactory.decodeFile(pathString); } } catch (Exception e) { // TODO: handle exception } return bitmap; } // SurfaceHodler Callback handle to open the camera, off camera and photo size changes SurfaceHolder.Callback surfaceCallback = new SurfaceHolder.Callback() { public void surfaceCreated(SurfaceHolder holder) { Log.i(TAG, "surfaceCallback===="); camera = Camera.open(); // Turn on the camera try { camera.setPreviewDisplay(holder); // Set Preview } catch (IOException e) { camera.release();// release camera camera = null; } } public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { Log.i(TAG,"====surfaceChanged"); Camera.Parameters parameters = camera.getParameters(); // Camera parameters to obtain parameters.setPictureFormat(PixelFormat.JPEG);// Setting Picture Format // parameters.set("rotation", 180); // Arbitrary rotation camera.setDisplayOrientation(0); parameters.setPreviewSize(400, 300); // Set Photo Size camera.setParameters(parameters); // Setting camera parameters camera.startPreview(); // Start Preview } public void surfaceDestroyed(SurfaceHolder holder) { Log.i(TAG,"====surfaceDestroyed"); camera.stopPreview();// stop preview camera.release(); // Release camera resources camera = null; } }; }

拍完以后自动保存到SD卡中的images目录下

下面是图片存放路径

1.8M 确实有点大,不过是高清图片

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