Android开发经验分享- 用相机录制视频

现在的手机一般都会提供相机功能，有些相机大镜头已经支持1000万以上的像素，有些还支持光学变焦，这些手机已经变成了专业数码相机，为了充分利用手机上的相机功能，Android应用可以控制拍照和录制视频。

首先在项目中添加以下权限

<!--摄像头相关-->

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

<uses-feature android:name="android.hardware.camera" />

<uses-feature android:name="android.hardware.camera.autofocus" />

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

<!--音视频相关-->

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

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

拍照

一、通过系统Intent进行拍照

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

创建Uri方法一：

//添加参数

ContentValues values = new ContentValues();

//设置文件名称

values.put(MediaStore.Images.Media.DISPLAY_NAME, String.valueOf(System.currentTimeMillis())+".jpg");

//设置文件类型

values.put(MediaStore.Images.Media.MIME_TYPE, "image/png");

//添加存储的位置的uri

uri = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);

创建Uri方法二：

File file = new File(Environment.getExternalStorageDirectory().getAbsolutePath()+"/"+System.currentTimeMillis()+".jpg");

uri = Uri.fromFile(file);

//添加图像方向

intent.putExtra(MediaStore.Images.Media.ORIENTATION, 0);

//设置图像输出位置

intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);

startActivityForResult(intent,1);

获取返回的图像路径

public static String getPathFromUri(Context mContext,Uri contentUri){

String[] proj = { MediaStore.Images.Media.DATA };

CursorLoader loader = new CursorLoader(mContext, contentUri, proj, null, null, null);

Cursor cursor = loader.loadInBackground();

int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);

cursor.moveToFirst();

return cursor.getString(column_index);

}

通过路径加载Bitmap

Bitmap bitmap = BitmapFactory.decodeFile(getPathFromUri(this, uri));

二、利用Camrea拍照

1、调用Camera的open()打开相机

2、调用Camera的getParameters()获取拍照参数。该方法返回一个Camera.Paremeters对象

3、调用Camera.Parameters对象方法设置拍照的参数

4、调用Camera.startPreview()方法开始预览取景，在预览取景之前需要调用Camera的setPreviewDisplay(SurfaceHolder holder)方法设置使用哪个SurfaceView来显示取景图片。

5、调用Camera的takePicture()方法进行拍照

6、结束程序时，调用Camera的stopPreview()结束取景预览，并调用release()方法释放资源

public class CameraActivity extends Activity {

private SurfaceView mSurfaceView;

private View mTake,mCancle;

private SurfaceHolder mSurfaceHolder;

private boolean isPreview = false;

private Camera mCamera;

private Camera.AutoFocusCallback autoFocusCallback = new Camera.AutoFocusCallback() {

@Override

public void onAutoFocus(boolean success, Camera camera) {

if(success){

// 第一个监听器；当用户按下快门时激发该监听器

// 第二个监听器；当相机获取原始照片时激发该监听器

// 第三个监听器；当相机获取JPG照片时激发该监听器

mCamera.takePicture(new Camera.ShutterCallback() {

@Override

public void onShutter() {

//快门按下时

}

}, new Camera.PictureCallback() {

@Override

public void onPictureTaken(byte[] data, Camera camera) {

//此处代码可以决定是否需要保存原始照片信息

}

}, new Camera.PictureCallback() {

@Override

public void onPictureTaken(byte[] data, Camera camera) {

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

//创建矩阵 旋转图像

Matrix matrix = new Matrix();

matrix.setRotate(90f,bitmap.getWidth()/2,bitmap.getHeight()/2);

Bitmap bit =Bitmap.createBitmap(bitmap,0,0,bitmap.getWidth(),bitmap.getHeight(),matrix,true);

//销毁原图

bitmap.recycle();

mImage.setImageBitmap(bit);

File file = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis()+".jpg");

FileOutputStream fos = null;

try {

fos = new FileOutputStream(file);

bit.compress(Bitmap.CompressFormat.JPEG,100,fos);

try {

fos.close();

} catch (IOException e) {

e.printStackTrace();

}

} catch (FileNotFoundException e) {

e.printStackTrace();

}

mCamera.stopPreview();;

mCamera.startPreview();

isPreview=true;

}

});

}

}

};

private ImageView mImage;

@Override

protected void onCre

ate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_camera);

initView();

process();

setAllClick();

}

private void setAllClick() {

mSurfaceHolder.addCallback(new SurfaceHolder.Callback() {

@Override

public void surfaceCreated(SurfaceHolder holder) {

initCamera();

}

@Override

public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

}

@Override

public void surfaceDestroyed(SurfaceHolder holder) {

if (mCamera != null) {

if (isPreview) {

mCamera.stopPreview();

mCamera.release();

mCamera = null;

}

}

}

});

mTake.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

//拍照

if (mCamera != null) {

//添加自动聚焦

mCamera.autoFocus(autoFocusCallback);

// takePhoto();

}

}

});

}

private int mPreviewWidth=0;

private int mPreviewHeight=0;

/**

* 初始化相机

*/

private void initCamera() {

if(!isPreview){

//打开相机

// mCamera = Camera.open(Camera.getNumberOfCameras()-1);

mCamera = Camera.open(0);

}

if(mCamera!=null&&!isPreview){

//获取相关设置

Camera.Parameters parameters = mCamera.getParameters();

List<Camera.Size> previewsizes = parameters.getSupportedPreviewSizes();

Iterator<Camera.Size> iterator = previewsizes.iterator();

while(iterator.hasNext()){

Camera.Size next = iterator.next();

if(next.width>mPreviewWidth&&next.height>mPreviewHeight){

mPreviewWidth=next.width;

mPreviewHeight=next.height;

}

Log.i("TAG","camera->"+mPreviewWidth+":"+mPreviewHeight);

}

Log.i("TAG","surface->"+mSurfaceView.getWidth()+":"+mSurfaceView.getHeight());

//设置预览招聘时每秒显示多少帧的最小值和最大值

// parameters.setPreviewFpsRange(10, 20);

//设置图片格式

parameters.setPictureFormat(PixelFormat.JPEG);

//设置预览大小

// parameters.setPreviewSize(mPreviewWidth, mPreviewHeight);

//设置照片大小

parameters.setPictureSize(mPreviewWidth, mPreviewHeight);

//设置JPG照片的质量

parameters.set("jpeg-quality", 100);

//设置取景的SutfaceView

try {

//设置显示方向

mCamera.setDisplayOrientation(90);

mCamera.setParameters(parameters);

//设置配置

mCamera.setPreviewDisplay(mSurfaceHolder);

mCamera.startPreview();

} catch (IOException e) {

e.printStackTrace();

}

}

isPreview=true;

}

/**

* 业务过程

*/

private void process() {

mSurfaceHolder = mSurfaceView.getHolder();

//设置Surface不需要自己维护还冲区

mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

}

/**

* 初始化视图

*/

private void initView() {

mSurfaceView =(SurfaceView) findViewById(R.id.camera_view);

mTake = findViewById(R.id.take_photo);

mCancle = findViewById(R.id.cancle);

mImage = (ImageView)findViewById(R.id.image);

}

}

录像

一、使用系统Intent

Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);

//限制时长 s

intent.putExtra(MediaStore.EXTRA_DURATION_LIMIT, 5);

//限制大小

intent.putExtra(MediaStore.EXTRA_SIZE_LIMIT, 1024*1024);

//设置质量

intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);

//设置输出位置

intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);

startActivityForResult(intent, 1);

返回

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);

if(resultCode==RESULT_OK){

Uri uri = data.getData();

//视频地址

String videoPath = getPathFromUri(this,uri);

}

}

public static String getPathFromUri(Context mContext,Uri contentUri){

String[] proj = { MediaStore.Images.Media.DATA };

CursorLoader loader = new CursorLoader(mContext, contentUri, proj, null, null, null);

Cursor cursor = loader.loadInBackground();

int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);

cursor.moveToFirst();

return cursor.getString(column_index);

}

二、使用MediaRecord

public class RecordeActivity extends Activity {

private SurfaceView mRecordView;

private View mStart, mStop;

private boolean isRecord = false;

private SurfaceHolder mSurfaceHolder;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_recorde);

initView();

process();

setAllClick();

}

private void setAllClick() {

mStart.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

if(!isRecord){

startRecord();

}

}

});

mStop.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

if(isRecord){

//停止录制

mRecorder.stop();

//释放资源

mRecorder.release();

mRecorder=null;

}

}

});

}

private File file;

private MediaRecorder mRecorder;

/**

* 开始录制

*/

private void startRecord() {

file = new File(Environment.getExternalStorageDirectory() + "/" + System.currentTimeMillis() + ".mp4");

try {

//创建MediaPay对象

mRecorder = new MediaRecorder();

mRecorder.reset();

//设置从麦克风采集声音

mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);

//设置从摄像头采集图像

mRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

mRecorder.setOrientationHint(90);

//设置视频文件输出格式，这个设置必须在声音编码格式，图像编码格式之前设置

mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);

//设置声音编码格式、图像编码格式

mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);

mRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.MPEG_4_SP);

//设置视频大小

mRecorder.setVideoSize(1280, 960);

//设置帧率 每秒32帧

mRecorder.setVideoFrameRate(32);

//设置编码比特率

mRecorder.setVideoEncodingBitRate(5*1024*1024);

mRecorder.setOutputFile(file.getAbsolutePath());

//指定使用Surface来预览视频

mRecorder.setPreviewDisplay(mSurfaceHolder.getSurface());

//准备

mRecorder.prepare();

//开始录制

mRecorder.start();

isRecord = true;

} catch (IOException e) {

e.printStackTrace();

}

}

private void process() {

mSurfaceHolder = mRecordView.getHolder();

mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

mSurfaceHolder.setKeepScreenOn(true);

}

private void initView() {

mRecordView = (SurfaceView) findViewById(R.id.video_recorde);

mStart = findViewById(R.id.start);

mStop = findViewById(R.id.stop);

}

}

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