分享磨砺营马剑威老师讲解-Android开发中相机录制视频的实现

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
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");
FileOutputStr
3ff8
eam 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 onCreate(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 previewsizes = parameters.getSupportedPreviewSizes();
Iterator 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, 10241024);
//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(510241024);
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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