// Shoot page
mVideoView = mVideoViewFollowShotRecord;
// Played back video
mFollowShotVideoPath = intent.getStringExtra(TCConstants.VIDEO_EDITER_PATH);
mFollowShotVideoDuration = (int)(intent.getFloatExtra(TCConstants.VIDEO_RECORD_DURATION, 0) * 1000);
initPlayer();
// The maximum length of the shoot progress bar should be the length of the source video. The frame rate (`fps`) of the source video should also be used for the shot video
mMaxDuration = (int)mFollowShotVideoDuration;
mFollowShotVideoFps = intent.getIntExtra(TCConstants.RECORD_CONFIG_FPS, 20);
mFollowShotAudioSampleRateType = intent.getIntExtra(TCConstants.VIDEO_RECORD_AUDIO_SAMPLE_RATE_TYPE, TXRecordCommon.AUDIO_SAMPLERATE_48000);
// Initialize the duet API
mTXVideoJoiner = new TXVideoJoiner(this);
mTXVideoJoiner.setVideoJoinerListener(this);

// Initialize the player. Here, `TXVideoEditer` is used. You can also use `TXVodPlayer`
mTXVideoEditer = new TXVideoEditer(this);
mTXVideoEditer.setVideoPath(mFollowShotVideoPath);
TXVideoEditConstants.TXPreviewParam param = new TXVideoEditConstants.TXPreviewParam();
param.videoView = mVideoViewPlay;
param.renderMode = TXVideoEditConstants.PREVIEW_RENDER_MODE_FILL_EDGE;
mTXVideoEditer.initWithPreview(param);

customConfig.videoFps = mFollowShotVideoFps;
customConfig.audioSampleRate = mFollowShotAudioSampleRateType; // The audio sample rate of the shot video must be the same as that of the source video
customConfig.needEdit = false;
mTXCameraRecord.setVideoRenderMode(TXRecordCommon.VIDEO_RENDER_MODE_ADJUST_RESOLUTION); // Set the rendering mode to fit mode
mTXCameraRecord.setMute(true); // The duet audio played back by the speaker will not be recorded, because if it is recorded by mic, the source and shot videos' audios will be mixed

private void prepareToJoiner(){
 List<String> videoSourceList = new ArrayList<>();
 videoSourceList.add(mRecordVideoPath);
 videoSourceList.add(mFollowShotVideoPath);
 mTXVideoJoiner.setVideoPathList(videoSourceList);
 mFollowShotVideoOutputPath = getCustomVideoOutputPath("Follow_Shot_");
 // Proportionally scale the video on the right by the width and height of the shot video on the left
 int followVideoWidth;
 int followVideoHeight;
 if ((float) followVideoInfo.width / followVideoInfo.height >= (float)recordVideoInfo.width / recordVideoInfo.height) {
     followVideoWidth = recordVideoInfo.width;
     followVideoHeight = (int) ((float)recordVideoInfo.width * followVideoInfo.height / followVideoInfo.width);
 } else {
     followVideoWidth = (int) ((float)recordVideoInfo.height * followVideoInfo.width / followVideoInfo.height);
     followVideoHeight = recordVideoInfo.height;
 }

 TXVideoEditConstants.TXAbsoluteRect rect1 = new TXVideoEditConstants.TXAbsoluteRect();
 rect1.x = 0;                     // Top-left point position of the first video
 rect1.y = 0;
 rect1.width = recordVideoInfo.width;   // Width and height of the first video
 rect1.height = recordVideoInfo.height;

 TXVideoEditConstants.TXAbsoluteRect rect2 = new TXVideoEditConstants.TXAbsoluteRect();
 rect2.x = rect1.x + rect1.width; // Top-left point position of the second video
 rect2.y = (recordVideoInfo.height - followVideoHeight) / 2;
 rect2.width = followVideoWidth;  // Width and height of the second video
 rect2.height = followVideoHeight;

 List<TXVideoEditConstants.TXAbsoluteRect> list = new ArrayList<>();
 list.add(rect1);
 list.add(rect2);
 mTXVideoJoiner.setSplitScreenList(list, recordVideoInfo.width + followVideoWidth, recordVideoInfo.height); // The second and third parameters: width and height of the video composition canvas
 mTXVideoJoiner.splitJoinVideo(TXVideoEditConstants.VIDEO_COMPRESSED_540P, mFollowShotVideoOutputPath);
}

@Override
public void onJoinComplete(TXVideoEditConstants.TXJoinerResult result) {
 mCompleteProgressDialog.dismiss();
 if(result.retCode == TXVideoEditConstants.JOIN_RESULT_OK){
     runOnUiThread(new Runnable() {
         @Override
         public void run() {
             isReadyJoin = true;
             startEditerPreview(mFollowShotVideoOutputPath);
             if(mTXVideoEditer != null){
                 mTXVideoEditer.release();
                 mTXVideoEditer = null;
             }
         }
     });
 }else{
     runOnUiThread(new Runnable() {
         @Override
         public void run() {
             Toast.makeText(TCVideoRecordActivity.this, "Composition failed", Toast.LENGTH_SHORT).show();
         }
     });
 }
}