updated post and edited.
1: i first create 5 seconds clip using 55.png.
55.png click here
2: i create intermediate1.ts using outputxx.mp4
3: than i create intermediate2.ts using 55.mp4
4:finally i use the last command
problem is the second video clip does not show but sound plays and i want it to show its original size after first video clip has finished.
original size
https://streamable.com/jpkqps
ffmpeg -loop 1 -i 55.png -t 5 -vcodec mpeg2video -s 1280x720 -acodec copy -f mpegts -y outputxx.mp4
ffmpeg -i outputxx.mp4 -vcodec mpeg2video -s 1280x720 -q:v 1 -acodec copy -f mpegts -y intermediate1.ts
ffmpeg -i 55.mp4 -c copy -bsf:v h264_mp4toannexb -f mpegts -s 1920x1080 -q:v 1 -c:a copy -y intermediate2.ts
ffmpeg -i "concat:intermediate1.ts|intermediate2.ts" -c copy -y output.mp4
so main results should be like first clip should play then start the second just like you will add intro then the video
can i modify this to make conversion faster
ffmpeg -i "concat:intermediate1.ts|intermediate2.ts" -vcodec libx264 -s 1280x720 -aspect 16:9 -q:v 1 -preset fast -c:a copy -f mpegts -y output1.ts.
or what is the fastest way to make 5 seconds clip from 55.png then add a 55.mp4
this is not right probly but it will give you idea.
ffmpeg -loop 1 -i 55.png -t 5 -vcodec mpeg2video -s 1280x720 -acodec copy -f mpegts i- 55.mp4 -y intermediate1.ts