FFMPEG shows error message
You can only pad frames to a size as large as or larger than the source size. In your case, 16/9 multiplier of 1500 is 2666.66 which is rounded down to 2666 and hence smaller than source width. Since your source aspect is so close, just skip the pad.
&quot;/usr/bin/ffmpeg&quot; -y -f concat -safe 0 -i &quot;/home/abc/def/data/tmp/gVQO7wUc.txt&quot; -vf &quot;scale=1920:1080:flags=lanczos,setsar=1&quot; -c:v libx264 -crf 18 -preset veryslow -pix_fmt yuv420p -movflags +faststart &quot;/home/abc/def/data/tmp/964MX26P.mp4&quot;