android - Camera.open() occur error (using MediaRecorder) -

my action flow:

1. camera.open()
2. camera.unlock()
3. recorder = new mediarecorder();
4. recorder.setcamera(), , then.. more setting.

(click start button)

5. recorder.start()

(click stop button)

6. recorder.stop()
7. recorder.release()
8. recorder = null;

(save recorded video file)

9. camera.open() <= occur error

step 9 recording again more video.

but, step occur error.

it's logcat :

it's source :

---

public class talk extends activity implements surfaceholder.callback{

context context;   surfaceview sfv_preview; progressbar progressbar; private surfaceholder holder; private mediarecorder recorder = null; camera camera;  boolean recording = false;  private static final string output_file = "/sdcard/vitalk/temp.mp4"; private static final string output_file_name = "temp.mp4"; private static final int recording_time = 10000;  //uri fileuri;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_talk);       file mediastoragedir = new file("/sdcard/vitalk/");     if (!mediastoragedir.exists()) mediastoragedir.mkdirs();      sfv_preview = (surfaceview) findviewbyid(r.id.sfv_preview);     progressbar = (progressbar) findviewbyid(r.id.progressbar);      holder = sfv_preview.getholder();     holder.addcallback(this);     holder.settype(surfaceholder.surface_type_push_buffers);        initrecorder();        context = this;       ((imagebutton)findviewbyid(r.id.ibt_record)).setontouchlistener(new ontouchlistener(){          @override         public boolean ontouch(view v, motionevent event) {             if (motionevent.action_down == event.getaction()) {                 sfv_preview.setvisibility(view.visible);                 recorder.start();                 recording = true;                 log.d("recod", "click start");             }             else if (motionevent.action_up == event.getaction() || event.getaction() == motionevent.action_cancel) {                 log.d("recod", "click stop");                 if (recording) {                     recorder.stop();                     recording = false;                     recorder.release();                     new handler().post(new runnable() {                         @suppresslint("newapi")                         @override                         public void run() {                             progressbar.setvisibility(view.visible);                         }                     });                      uploadfile(output_file);                       recorder = null;                      initrecorder();                     preparerecorder();                    }             }             return false;         }     });  }   @override public void surfacecreated(surfaceholder holder) {     // todo auto-generated method stub     preparerecorder(); }  @override public void surfacechanged(surfaceholder holder, int format, int width,         int height) {     // todo auto-generated method stub  }  @override public void surfacedestroyed(surfaceholder holder) {     // todo auto-generated method stub }  private void initrecorder() {      camera camera = camera.open(1);     camera.setdisplayorientation(90);     camera.unlock();       recorder = new mediarecorder();     recorder.setcamera(camera);      recorder.setaudiosource(mediarecorder.audiosource.mic);     recorder.setvideosource(mediarecorder.videosource.camera);      recorder.setprofile(camcorderprofile.get(camcorderprofile.quality_480p));       recorder.setoutputfile(output_file);     recorder.setmaxduration(recording_time);     recorder.setmaxfilesize(10485760); // approximately 5 megabytes }  private void preparerecorder() {     recorder.setpreviewdisplay(holder.getsurface());     recorder.setorientationhint(90);      try {         recorder.prepare();         //finish();     } catch (illegalstateexception e) {         e.printstacktrace();         //finish();     } catch (ioexception e) {         e.printstacktrace();         //finish();     } }  public void uploadfile(string sourcefileuri) {      string filename = sourcefileuri;      httpurlconnection conn = null;     dataoutputstream dos = null;      string lineend = "\r\n";     string twohyphens = "--";     string boundary = "*****";     int bytesread, bytesavailable, buffersize;     byte[] buffer;     int maxbuffersize = 1 * 1024 * 1024;     file sourcefile = new file(sourcefileuri);        try {             // open url connection servlet          fileinputstream fileinputstream = new fileinputstream(sourcefile);          url url = new url("http://133.130.117.56/visualtalk/func/fileupload.php");           // open http  connection  url          conn = (httpurlconnection) url.openconnection();          conn.setdoinput(true); // allow inputs          conn.setdooutput(true); // allow outputs          conn.setusecaches(false); // don't use cached copy          conn.setrequestmethod("post");          conn.setrequestproperty("connection", "keep-alive");          conn.setrequestproperty("enctype", "multipart/form-data");          conn.setrequestproperty("content-type", "multipart/form-data;boundary=" + boundary);          conn.setrequestproperty("uploaded_file", filename);           dos = new dataoutputstream(conn.getoutputstream());           dos.writebytes(twohyphens + boundary + lineend);          dos.writebytes("content-disposition: form-data; name=\"uploaded_file\";filename=\""                  + filename + "\"" + lineend);           dos.writebytes(lineend);           // create buffer of  maximum size          bytesavailable = fileinputstream.available();           buffersize = math.min(bytesavailable, maxbuffersize);          buffer = new byte[buffersize];           // read file , write form...          bytesread = fileinputstream.read(buffer, 0, buffersize);            while (bytesread > 0) {             dos.write(buffer, 0, buffersize);            bytesavailable = fileinputstream.available();            buffersize = math.min(bytesavailable, maxbuffersize);            bytesread = fileinputstream.read(buffer, 0, buffersize);              }           // send multipart form data necesssary after file data...          dos.writebytes(lineend);          dos.writebytes(twohyphens + boundary + twohyphens + lineend);           // responses server (code , message)          int serverresponsecode = conn.getresponsecode();          string serverresponsemessage = conn.getresponsemessage();           log.i("uploadfile", "http response : "                  + serverresponsemessage + ": " + serverresponsecode);           if(serverresponsecode == 200){            }              //close streams //          fileinputstream.close();          dos.flush();          dos.close();        } catch (malformedurlexception ex) {         log.e("upload file server", "error: " + ex.getmessage(), ex);      } catch (exception e) {          log.e("upload file server exception", "exception : "                                          + e.getmessage(), e);      }         new handler().post(new runnable() {             @suppresslint("newapi")             @override             public void run() {                  sfv_preview.setvisibility(view.invisible);                 progressbar.setvisibility(view.invisible);             }         });  } 

}

what problem?..

maybe should try use camera.release() before next open()