How to insert alternate frames from multipule video sources to create a single output file using ffmpeg

I have a 4K 50fps video file that is split into 4 quadrants (only 3 are needed). It is generated by a slow motion camera running at 150 FPS. Each of the quadrants contains the same image shifted by a frame.

I want to cut out the 3 sections of the picture, take a frame from each image and insert them sequentially. This will result in a 1920×1080 50FPS clip 3 times a long as the original, but the motion in the picture will run slower.

I know how to cut the sections from the image, but I’m struggling to find a filter to insert the frames sequentially.

ffmpeg -i TriMotion.ts -filter:v "crop=1920:1080:0:0" out.mp4

ffmpeg -i TriMotion.ts -filter:v "crop=1920:1080:1920:0" out.mp4

ffmpeg -i TriMotion.ts -filter:v "crop=1920:1080:0:1080" out.mp4

I have tried the following, but the output is normal speed;

ffmpeg -i TriMotion.ts -filter_complex "[0]crop=1920:1080:0:0[v1];[0]crop=1920:1080:1920:0[v2];[0]crop=1920:1080:0:1080[v3];[v1][v2][v3] interleave=nb_inputs=3" -c:v libx265

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