FFmpeg guides & templates

-i $MEDIA_1
-i $MEDIA_2
-filter_complex
[0:v]loop=loop=150:size=1:start=0,setdar=16/9,scale=1280:720:force_original_aspect_ra
[1:v]loop=loop=150:size=1:start=0,setdar=16/9,scale=1280:720:force_original_aspect_ra
[v0?][v1?]concat=n=2:v=1:a=0,settb=expr=1/30[c1?];
[c1?]settb=expr=1/30[v_layer0];
[v_layer0]split[v_main][v_overlay];[v_main]settb=expr=1/30[v_concat];[v_overlay]nullsink
aevalsrc=0:d=5[s0];[s0]adelay=delays=0|0,volume=10[a0?];
aevalsrc=0:d=5[s1];[s1]adelay=delays=5000|5000,volume=10[a1?];
[a0?][a1?]amix=inputs=2:duration=longest[a_concat]
-aspect 16/9
-movflags +faststart
-map [v_concat]
-map [a_concat]
-r 30
-ss 00:00:00
-to 00:00:10
-y $OUTPUT_PATH