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最近完善了一下相机的app，除了拍照功能，现在增加了开启闪光灯，切换前后置摄像头，相册功能，图片删除，图片分享功能，设置照片大小，以及照片的质量，视频方面，有录制视频，设置视频录制大小，本应用拍摄的视频预览，以及视频播放界面。

下面是应用的一些截图，由于项目是自己开发，没有美工优化界面，所以界面比较难看，另外附上github的地址：代码方面并没有做过多的优化，只是供新人学习相机开发流程，大神勿喷：

github : https://github.com/jingxiongdi/CameraJXD

应用部分界面截图：

记录一下Android摄像头拍照的问题：

前言：权限问题，一定别忘记

    <uses-permission android:name="android.permission.FLASHLIGHT" />    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <uses-permission android:name="android.permission.CAMERA" />    <uses-feature android:name="android.hardware.camera" />    <uses-feature android:name="android.hardware.camera.autofocus" />

1.摄像头开启：0为后置，1为前置

判断是否有前后置摄像头

由于getNumberOfCameras以及getCameraInfo均为API 9 引入，所以方法只适用于2.3及其以上

private boolean checkCamera(final int facing) {     if (getSdkVersion() < Build.VERSION_CODES.GINGERBREAD) {         return false;     }     final int cameraCount = Camera.getNumberOfCameras();     CameraInfo info = new CameraInfo();     for (int i = 0; i < cameraCount; i++) {         Camera.getCameraInfo(i, info);         if (facing == info.facing) {             return true;         }     }     return false; } public static boolean hasBackFacingCamera() {     final int CAMERA_FACING_BACK = 0;     return checkCameraFacing(CAMERA_FACING_BACK); } public static boolean hasFrontFacingCamera() {     final int CAMERA_FACING_FRONT = 1;     return checkCameraFacing(CAMERA_FACING_FRONT); } public static int getSdkVersion() {     return android.os.Build.VERSION.SDK_INT; } 

mCamera = Camera.open(0);

public void setCameraDisplayOrientation ( Activity activity , int cameraId , android.hardware.Camera camera )    { android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo(); android.hardware.Camera.getCameraInfo ( cameraId , info );        int rotation = activity.getWindowManager ().getDefaultDisplay ().getRotation ();        int degrees = 0 ;        switch ( rotation )        {            case Surface.ROTATION_0 :                degrees = 0 ;                break ;            case Surface.ROTATION_90 :                degrees = 90 ;                break ;            case Surface.ROTATION_180 :                degrees = 180 ;                break ;            case Surface.ROTATION_270 :                degrees = 270 ;                break ;        }        int result = 0;        if ( info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT )        {            result = ( info.orientation + degrees ) % 360 ;            result = ( 360 - result ) % 360 ; // compensate the mirror        }        else        {         // back-facing             result = ( info.orientation - degrees + 360 ) % 360 ;        }        camera.setDisplayOrientation ( result );    }

4.获取和设置相机参数：

   try {                Camera.Parameters parameters = mCamera.getParameters();//                List<Camera.Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();//                for(int i = 0; i<supportedPreviewSizes.size();i++)//                {//                    Log.d("jxd","supportedPreviewSizes : "+supportedPreviewSizes.get(i).width +" * "+supportedPreviewSizes.get(i).height);//                }                List<Camera.Size> supportedVideoSize =  parameters.getSupportedVideoSizes();                for(int i = 0; i<supportedVideoSize.size();i++)                {                    Log.d("jxd","supportedVideoSize : "+supportedVideoSize.get(i).width +" * "+supportedVideoSize.get(i).height);                }//                List<Camera.Size> supportedJpegThumbnailSizes = parameters.getSupportedJpegThumbnailSizes();//                for(int i = 0; i<supportedJpegThumbnailSizes.size();i++)//                {//                    Log.d("jxd","supportedJpegThumbnailSizes : "+supportedJpegThumbnailSizes.get(i).width +" * "+supportedJpegThumbnailSizes.get(i).height);//                }                if(!Hawk.contains(Contants.PHOTO_SIZE))                {                    List<Camera.Size> supportedPictureSizes =  parameters.getSupportedPictureSizes();                    for(int i = 0; i<supportedPictureSizes.size();i++)                    {                        Log.d("jxd","supportedPictureSizes : "+supportedPictureSizes.get(i).width +" * "+supportedPictureSizes.get(i).height);                    }                    Hawk.put(Contants.PHOTO_SIZE,supportedPictureSizes);                }//                List<int[]> supportedPreviewFpsRange = parameters.getSupportedPreviewFpsRange();//                for(int i = 0; i<supportedPreviewFpsRange.size();i++)//                {//                    Log.d("jxd","supportedPreviewFpsRange : =============== "+supportedPreviewFpsRange.get(i).length);//                    for(int k = 0;k<supportedPreviewFpsRange.get(i).length;k++)//                    {//                        Log.d("jxd","supportedPreviewFpsRange : "+supportedPreviewFpsRange.get(i)[k]);//                    }//                }                //设置预览照片的大小        //        parameters.setPreviewFpsRange(viewWidth, viewHeight);                //设置相机预览照片帧数         //      parameters.setPreviewFpsRange(4, 10);                //设置图片格式                parameters.setPictureFormat(ImageFormat.JPEG);                //设置图片的质量                int pos = 100;                if(Hawk.contains(Contants.CURRENT_PHOTO_QUALITY))                {                    String p = Hawk.get(Contants.CURRENT_PHOTO_QUALITY);                    try {                        pos = Integer.parseInt(p);                    }                    catch (Exception e)                    {                        e.printStackTrace();                    }                    Log.d("jxd","jpeg CURRENT_PHOTO_QUALITY : "+pos);                }                parameters.set("jpeg-quality", pos);                //设置照片的大小                Camera.Size size = null;                if(Hawk.contains(Contants.CURRENT_PHOTO_SIZE))                {                    int p  = Hawk.get(Contants.CURRENT_PHOTO_SIZE);                    size = parameters.getSupportedPictureSizes().get(p);                    Log.d("jxd","jpeg CURRENT_PHOTO_SIZE : "+size.width+" * "+size.height);                }                if(size != null)                {                    parameters.setPictureSize(size.width, size.height);                }                else                {                    parameters.setPictureSize(viewWidth, viewHeight);                }                parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);                mCamera.setParameters(parameters);

5.开启预览

                //通过SurfaceView显示预览                mCamera.setPreviewDisplay(mHolder);                //开始预览                mCamera.startPreview();

6.点击拍照以及设置图片旋转

 private void takePhoto() {        if (mCamera == null ) {            return;        }       // mCamera.stopPreview();        Log.d("jxd","takePhoto ");        mCamera.takePicture(null, null, 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("jxd", "fname="+fname+";dir="+ Environment.getExternalStorageDirectory());            //picture = new File(Environment.getExternalStorageDirectory(),fname);// create file            File picture = new File(Environment.getExternalStorageDirectory()+"/CameraJXD/"+fname);            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();            }            /**             * 解决照片旋转90度的问题             */            Bitmap bitmap = BitmapFactory.decodeFile(picture.getPath());            Matrix matrix = new Matrix();            matrix.postRotate(90);            Bitmap dstbmp = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(),                    matrix, true);            FileOutputStream fOut = null;            try {                fOut = new FileOutputStream(Environment.getExternalStorageDirectory()+"/CameraJXD/"+"rotate"+fname);                dstbmp.compress(Bitmap.CompressFormat.JPEG, 90, fOut);                fOut.flush();                fOut.close();            } catch (Exception e) {            }            picture.delete();            return null;        }    }