// Create TXVideoJoiner (nil for preview param indicates no preview needed)
TXVideoJoiner* _videoJoin = [[TXVideoJoiner alloc] initWithPreview:nil];

// Set video files to concatenate (_composeArray)
[_videoJoin setVideoPathList:_composeArray];

// Set delegate for progress/completion callbacks
_videoJoin.joinerDelegate = self;

// Start merging (540p compressed output)
[_videoJoin joinVideo:VIDEO_COMPRESSED_540P videoOutputPath:_outFilePath];

// Configure preview view
TXPreviewParam *param = [[TXPreviewParam alloc] init];
param.videoView = _videoPreview.renderView;
param.renderMode = PREVIEW_RENDER_MODE_FILL_EDGE;

// Create TXVideoJoiner with preview
TXVideoJoiner* _videoJoin = [[TXVideoJoiner alloc] initWithPreview:param];
_videoJoin.previewDelegate = _videoPreview;

// Set video files
[_videoJoin setVideoPathList:_composeArray];

// Start preview playback
[_videoJoin startPlay];

TXVideoJoiner* _videoJoin = [[TXVideoJoiner alloc] initWithPreview:nil];
[_videoJoin setVideoPathList:_composeArray];
_videoJoin.joinerDelegate = self;

// Configure split-screen layout
TXSplitScreenParams* splitScreenParams = [[TXSplitScreenParams alloc] init];
splitScreenParams.canvasWidth = 720 * 2;  // Total output width
splitScreenParams.canvasHeight = 1280;     // Total output height

// Define positions for each video
splitScreenParams.rects = @[
    [NSValue valueWithCGRect:CGRectMake(0, 0, splitScreenParams.canvasWidth/2, splitScreenParams.canvasHeight)],
    [NSValue valueWithCGRect:CGRectMake(splitScreenParams.canvasWidth/2, 0, splitScreenParams.canvasWidth/2, splitScreenParams.canvasHeight)]
];

splitScreenParams.durationMode = ALIGNS_TO_LONGEST;  // Duration matches longest input
[_videoJoiner setSplitScreenList:splitScreenParams];

// Set audio mix ratios (0: muted, 1: full volume)
[_videoJoiner setVideoVolumes:@[@0, @1]];

// Start merging
[_videoJoin joinVideo:VIDEO_COMPRESSED_540P videoOutputPath:_outFilePath];