Step1 To concatenate the two videos together, and exports the resulting video, with a (resized) width of 240 pixels and moderately heavy compression:
ffmpeg -i tile.MOV -i silver.MOV -filter_complex “[0:v]scale=240:-2[v0];[1:v]scale=240:-2[v1];[v0][0:a][v1][1:a]concat=n=2:v=1:a=1[v][a]” -map “[v]” -map “[a]” -c:v libx264 -crf 28 -preset medium test.MOV
Step2 To convert a .mov file to .mp4 because workpress only preview mp4:
ffmpeg -i test.mov -vcodec h264 -acodec aac test.mp4