Unknown encoder 'libx264'

[ominfowave]

Describe the bug
Getting this error message while applying complex filter "Unknown encoder 'libx264'"

To Reproduce
Use the following command:
"-i " + clipUri + " -i " + videoUri + " -t 0.1 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 -filter_complex " +
"[0:v]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:-1:-1,setsar=1,fps=30,format=yuv420p[v0];" +
"[1:v]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:-1:-1,setsar=1,fps=30,format=yuv420p[v1];" +
"[1:a]aformat=sample_rates=48000:channel_layouts=stereo[a1];" +
"[v0][2:a][v1][a1]concat=n=2:v=1:a=1[v][a]" +
" -map [v] -map [a] -c:v libx264 -c:a aac -movflags +faststart " + outputUri

Expected behavior
Merged video output file

Smartphone (please complete the following information):

• Device: Redmi note 5 pro
• OS: 9

[RGdevz]

same

[rehmanjameel]

Describe the bug Getting this error message while applying complex filter "Unknown encoder 'libx264'"

To Reproduce Use the following command: "-i " + clipUri + " -i " + videoUri + " -t 0.1 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 -filter_complex " + "[0:v]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720-1-1,setsar=1,fps=30,format=yuv420p[v0];" + "[1:v]scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720-1-1,setsar=1,fps=30,format=yuv420p[v1];" + "[1:a]aformat=sample_rates=48000:channel_layouts=stereo[a1];" + "[v0][2:a][v1][a1]concat=n=2:v=1:a=1[v][a]" + " -map [v] -map [a] -c:v libx264 -c:a aac -movflags +faststart " + outputUri

Expected behavior Merged video output file

Smartphone (please complete the following information):

• Device: Redmi note 5 pro
• OS: 9

Remove libx264 it will not work with it and use mpeg4 instead
visit these links:
https://superuser.com/a/944874
https://stackoverflow.com/a/67488418