Merge remote-tracking branch 'origin/master'

Author: azaat

README.md

@@ -1,6 +1,4 @@
-## RecSync Android: Sub-millisecond Video Synchronization of Multiple Android Smartphones
-
-Andrioid application which allows you to record synchronized smarpthone videos with sub-millisecond accuracy.
+![Logo](https://imgur.com/YtJA0E2.png)
 
 ### Usage:
 
@@ -21,6 +19,22 @@ Andrioid application which allows you to record synchronized smarpthone videos w
 3.  Adjust exposure and ISO to your needs.
 4.  Press the ```record video``` button to start synchronized video recording.
 
+#### Extraction and matching of the frames
+
+```
+Requirements:
+
+- Python
+- ffmpeg
+```
+
+1. Navigate to ```utils``` directory in the repository.
+2. Run ```./match.sh <VIDEO_1> <VIDEO_2>```.
+3. Frames will be extracted to directories ```output/1``` and ```output/2``` with timestamps in filenames, output directory will also contain ```match.csv``` file in the following format:
+    ```
+    timestamp_1(ns) timestamp_2(ns)
+    ```
+
 ### Our contribution:
 
 - Integrated **synchronized video recording**

app/src/main/java/com/googleresearch/capturesync/ImageMetadataSynchronizer.java

@@ -30,6 +30,7 @@
 
 import androidx.annotation.NonNull;
 
+import java.io.File;
 import java.util.ArrayList;
 import java.util.LinkedList;
 import java.util.List;
@@ -392,13 +393,18 @@ public void onCaptureCompleted(
           @Override
           public void onCaptureSequenceCompleted(@NonNull CameraCaptureSession session, int sequenceId, long frameNumber) {
             super.onCaptureSequenceCompleted(session, sequenceId, frameNumber);
-            Log.v(TAG, "YAAAY I've completed succesfully");
             if (context.getLastVideoSeqId() != null && sequenceId == context.getLastVideoSeqId() && context.getLogger() != null) {
               context.getMediaRecorder().stop();
-//        mLogger.close();
-//        mLogger = null;
+
+              if (context.isVideoRecording()) {
+                context.setVideoRecording(false);
+              } else {
+                // MediaRecorder created an empty video on preview, should perform a cleanup
+                  context.deleteUnusedVideo();
+              }
+
               context.getMediaRecorder().reset();
-              context.setVideoRecording(false);
+
               context.getLogger().close();
               context.setLogger(null);
             }

app/src/main/java/com/googleresearch/capturesync/MainActivity.java

@@ -79,7 +79,6 @@
 import java.util.Date;
 import java.util.List;
 import java.util.Locale;
-import java.util.concurrent.Future;
 import java.util.concurrent.FutureTask;
 import java.util.stream.Collectors;
 
@@ -95,6 +94,21 @@ public class MainActivity extends Activity {
     private String lastTimeStamp;
     private PeriodCalculator periodCalculator;
 
+    public String getLastVideoPath() {
+        return lastVideoPath;
+    }
+
+    public void deleteUnusedVideo() {
+        String videoPath = getLastVideoPath();
+        File videoFile = new File(videoPath);
+        boolean result = videoFile.delete();
+        if (!result) {
+            Log.d(TAG, "Video file could not be deleted");
+        }
+    }
+
+    private String lastVideoPath;
+
     public Integer getLastVideoSeqId() {
         return lastVideoSeqId;
     }
@@ -951,6 +965,7 @@ private void createRecorderSurface() throws IOException {
         MediaRecorder recorder = setUpMediaRecorder(surface, false);
         recorder.prepare();
         recorder.release();
+        deleteUnusedVideo();
     }
 
     private MediaRecorder setUpMediaRecorder(Surface surface) throws IOException {
@@ -968,8 +983,8 @@ private MediaRecorder setUpMediaRecorder(Surface surface, boolean specifyOutput)
          * set output file in media recorder
          */
 
-        String currentPath = getOutputMediaFilePath();
-        recorder.setOutputFile(currentPath);
+        lastVideoPath = getOutputMediaFilePath();
+        recorder.setOutputFile(lastVideoPath);
 
         CamcorderProfile profile = CamcorderProfile.get(CamcorderProfile.QUALITY_1080P);
         recorder.setVideoSize(profile.videoFrameWidth, profile.videoFrameHeight);