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如何从相机保存图片？

androidcamera
4

这是我的代码：

package com.commonsware.android.skeleton;

import android.app.Activity;
import android.content.Context;
import android.hardware.Camera;
import android.hardware.Camera.*;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Display;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;
import android.view.WindowManager;
import android.widget.FrameLayout;

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

// ----------------------------------------------------------------------

public class SimpleBulbActivity extends Activity {
    private Preview mPreview;
    private static final String TAG = "CameraDemo";
    FrameLayout preview;
    Camera mCamera;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Hide the window title.
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.main);
    }

    protected void onResume() {
        super.onResume();
        //Setup the FrameLayout with the Camera Preview Screen
        mPreview = new Preview(this);
        preview = (FrameLayout)findViewById(R.id.preview); 
        preview.addView(mPreview);
    }

    public void snap() {
        mCamera.takePicture(shutterCallback, rawCallback, jpegCallback);
    }
    ShutterCallback shutterCallback = new ShutterCallback() {
      public void onShutter() {
          Log.d(TAG, "onShutter'd");
      }
    };

    PictureCallback rawCallback = new PictureCallback() {
      public void onPictureTaken(byte[] _data, Camera _camera) {
          Log.d(TAG, "onPictureTaken - raw");
      }
    };

    PictureCallback jpegCallback = new PictureCallback() {
      public void onPictureTaken(byte[] data, Camera _camera) {
          FileOutputStream outStream = null;
            try {
                // write to local sandbox file system
                // outStream =
                // CameraDemo.this.openFileOutput(String.format("%d.jpg",
                // System.currentTimeMillis()), 0);
                // Or write to sdcard
                outStream = new FileOutputStream(String.format(
                        "/sdcard/%d.jpg", System.currentTimeMillis()));
                outStream.write(data);
                outStream.close();
                Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
            }
            Log.d(TAG, "onPictureTaken - jpeg");
      }
    };

 // ----------------------------------------------------------------------

    class Preview extends SurfaceView implements SurfaceHolder.Callback {
        SurfaceHolder mHolder;

        Preview(Context context) {
            super(context);

            // Install a SurfaceHolder.Callback so we get notified when the
            // underlying surface is created and destroyed.
            mHolder = getHolder();
            mHolder.addCallback(this);
            mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

        public void surfaceCreated(SurfaceHolder holder) {
            // The Surface has been created, acquire the camera and tell it where
            // to draw.
            mCamera = Camera.open();
            try {
               mCamera.setPreviewDisplay(holder);
               mCamera.setPreviewCallback(new PreviewCallback() {

                public void onPreviewFrame(byte[] data, Camera arg1) {
                    FileOutputStream outStream = null;
                    try {
                        outStream = new FileOutputStream(Environment.getExternalStorageDirectory().toString());
                        outStream.write(data);
                        outStream.close();
                        Log.d(TAG, "onPreviewFrame - wrote bytes: "
                                + data.length);
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    } finally {
                    }
                    Preview.this.invalidate();
                }
            });
        } catch (IOException e) {
                mCamera.release();
                mCamera = null;
                e.printStackTrace();
            }
        }

        public void surfaceDestroyed(SurfaceHolder holder) {
            // Surface will be destroyed when we return, so stop the preview.
            // Because the CameraDevice object is not a shared resource, it's very
            // important to release it when the activity is paused.
            mCamera.stopPreview();
            mCamera.release();
            mCamera = null;
        }


        private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
            final double ASPECT_TOLERANCE = 0.05;
            double targetRatio = (double) w / h;
            if (sizes == null) return null;

            Size optimalSize = null;
            double minDiff = Double.MAX_VALUE;

            int targetHeight = h;

            // Try to find an size match aspect ratio and size
            for (Size size : sizes) {
                double ratio = (double) size.width / size.height;
                if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }

            // Cannot find the one match the aspect ratio, ignore the requirement
            if (optimalSize == null) {
                minDiff = Double.MAX_VALUE;
                for (Size size : sizes) {
                    if (Math.abs(size.height - targetHeight) < minDiff) {
                        optimalSize = size;
                        minDiff = Math.abs(size.height - targetHeight);
                    }
                }
            }
            return optimalSize;
        }

        public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
            // Now that the size is known, set up the camera parameters and begin
            // the preview.
            Camera.Parameters parameters = mCamera.getParameters();

            List<Size> sizes = parameters.getSupportedPreviewSizes();
            Size optimalSize = getOptimalPreviewSize(sizes, w, h);

            Display display = ((WindowManager)getSystemService(WINDOW_SERVICE)).getDefaultDisplay();

            if(display.getRotation() == Surface.ROTATION_0)
            {
                parameters.setPreviewSize(optimalSize.height, optimalSize.width);                           
                mCamera.setDisplayOrientation(90);
            }

            if(display.getRotation() == Surface.ROTATION_90)
            {
                parameters.setPreviewSize(optimalSize.width, optimalSize.height);                         
            }

            if(display.getRotation() == Surface.ROTATION_180)
            {
                parameters.setPreviewSize(optimalSize.width, optimalSize.height);               
            }

            if(display.getRotation() == Surface.ROTATION_270)
            {
                parameters.setPreviewSize(optimalSize.width, optimalSize.height);
                mCamera.setDisplayOrientation(0);
            }

            mCamera.setParameters(parameters);
            mCamera.startPreview();
        }

    }

}

好的，我稍微修改了一下代码。

在我的主布局中，我有这样一个代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent" android:id="@+id/layout">
    <TextView android:layout_width="fill_parent"
        android:layout_height="wrap_content" android:text="Camera Demo"
        android:textSize="24sp" />

    <FrameLayout android:layout_weight="1" android:layout_width="fill_parent"
        android:layout_height="fill_parent">

    <FrameLayout android:id="@+id/preview"
        android:layout_weight="1" android:layout_width="fill_parent"
        android:layout_height="fill_parent">
    </FrameLayout>

    <ImageView android:src="@drawable/litbulb"
                   android:layout_width="match_parent"
                   android:layout_height="112dip" />

    </FrameLayout>

    <Button android:layout_width="wrap_content"
        android:layout_height="wrap_content" android:id="@+id/buttonClick"
        android:text="Snap!" android:layout_gravity="center"></Button>

</LinearLayout>

当我点击“Snap！”或buttonClick按钮时，应该捕获并保存图像，但实际上没有。有人能帮我修改这段代码吗？另外，每次离开应用程序时都会崩溃。以下是相关的日志数据：
12-21 13:30:47.820: ERROR/AndroidRuntime(3906): FATAL EXCEPTION: main
12-21 13:30:47.820: ERROR/AndroidRuntime(3906): java.lang.RuntimeException: Method called after release()
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.hardware.Camera.setHasPreviewCallback(Native Method)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.hardware.Camera.access$600(Camera.java:114)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.hardware.Camera$EventHandler.handleMessage(Camera.java:519)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.os.Handler.dispatchMessage(Handler.java:99)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.os.Looper.loop(Looper.java:123)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at android.app.ActivityThread.main(ActivityThread.java:4627)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at java.lang.reflect.Method.invokeNative(Native Method)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at java.lang.reflect.Method.invoke(Method.java:521)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
12-21 13:30:47.820: ERROR/AndroidRuntime(3906):     at dalvik.system.NativeStart.main(Native Method)
你可以尝试这个： https://dev59.com/zHRB5IYBdhLWcg3wXWG2 - Itian
3个回答
2

仅浏览您的代码，您需要将回调传递到takePicture方法中：

mPreview.getCamera().takePicture(shutterCallback, rawCallback,  null, jpegCallback);

请在此处查看更多详细信息。

您的堆栈跟踪似乎表明它不知道在拍照后该做什么。

此外，我怀疑您可能正在指向错误的根目录进行写入操作...尝试使用以下代码：

Environment.getExternalStorageDirectory().toString()
当我尝试这样做时，它会显示“SimpleBulbActivity.Preview的getCamera()方法未定义”。我应该在哪里插入第二行？ - Willem Ellis
好的，我按照我理解你的意思修改了代码。程序不再崩溃，但是图像仍然无法保存。 - Willem Ellis
抱歉，崩溃仍在发生。 - Willem Ellis
我找出了为什么它没有拍照的原因。现在它可以拍照了，但是当我离开应用程序时，在我的相册中看不到照片。有什么想法吗？ - Willem Ellis
它不会自动添加到您的相册中。谷歌正在添加照片到您的相册，以实现这一目标。 - Yevgeny Simkin
2
pre.camera.takePicture(shutterCallback, rawCallback,
                            jpegCallback);
            PictureCallback rawCallback = new PictureCallback() {
            public void onPictureTaken(byte[] data, Camera camera) {
                System.out.println( "onPictureTaken - raw");
            }
        };

        /** Handles data for jpeg picture */
        PictureCallback jpegCallback = new PictureCallback() {
            public void onPictureTaken(byte[] data, Camera camera) {


                 BitmapFactory.Options options=new BitmapFactory.Options();
                    options.inSampleSize = 5;

                m=BitmapFactory.decodeByteArray(data,0,data.length,options);
您需要调用回调函数，这样您的应用程序就不会崩溃。 - Reddy
好的，我觉得我已经理解你的意思了，崩溃问题已经解决，但是它仍然没有保存图片。 - Willem Ellis
抱歉，崩溃问题仍在发生。 - Willem Ellis
1
这是它：
public class PictureSaver {

private static final String TAG = "PictureSaver";

public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;

/** null if unable to save the file */
public static File savePicture(byte[] data, String folder_name) throws SaveFileException {
    File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE, folder_name);
    if (pictureFile == null){
        Log.d(TAG, "Error creating media file, check storage permissions!");
        throw new SaveFileException(TAG, "Error creating media file, check storage permissions!");
    }

    try {
        FileOutputStream fos = new FileOutputStream(pictureFile);
        fos.write(data);
        fos.close();
    } catch (FileNotFoundException e) {
        Log.d(TAG, "File not found: " + e.getMessage());
        throw new SaveFileException(TAG, "File not found: " + e.getMessage());
    } catch (IOException e) {
        Log.d(TAG, "Error accessing file: " + e.getMessage());
        throw new SaveFileException(TAG, "Error accessing file: " + e.getMessage());
    }
    return pictureFile;
}

/** Create a File for saving an image or video 
 *  null if unable to create the file */
private static File getOutputMediaFile(int type, String folder_name) throws SaveFileException {
    // To be safe, you should check that the SDCard is mounted
    // using Environment.getExternalStorageState() before doing this.

    File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
              Environment.DIRECTORY_PICTURES), folder_name);
    // This location works best if you want the created images to be shared
    // between applications and persist after your app has been uninstalled.

    // Create the storage directory if it does not exist
    if (! mediaStorageDir.exists()){
        if (! mediaStorageDir.mkdirs()){
            Log.d(TAG, "Unable to create directory!");
            throw new SaveFileException(TAG, "Unable to create directory!");
        }
    }

    // Create a media file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    File mediaFile;
    if (type == MEDIA_TYPE_IMAGE){
        mediaFile = new File(mediaStorageDir.getPath() + File.separator +
        "IMG_"+ timeStamp + ".jpg");
    } else if(type == MEDIA_TYPE_VIDEO) {
        mediaFile = new File(mediaStorageDir.getPath() + File.separator +
        "VID_"+ timeStamp + ".mp4");
    } else {
        throw new SaveFileException(TAG, "Unkknown media type!");
    }
    Log.d(TAG,mediaStorageDir.getPath() + File.separator +
            "IMG_"+ timeStamp + ".jpg");
    return mediaFile;
}}

记得还要做类似以下的事情：

sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
                         Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE,
                         Uri.parse("file://"+ Environment.getExternalStorageDirectory())));

如果图片已经被正确保存，那么下一次用户打开相册或其他媒体浏览应用程序时，您新拍摄的图像将会正确列出。
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