A imagem de fundo precisa ser cortada antes de ser usada na sobreposição
ffmpeg -loop 1 -i hinh1.jpg -i 2.mp4 \
-filter_complex "[1]scale=iw/2.5:-1[ovrl]; \
[0]crop=in_w:in_h-360[bg]; \
[bg][ovrl]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[v],\
[1]pan=stereo|c0<c0+0*c1|c1<c0+0*c1,aeval=val(0)|-val(1)[a]" \
-map "[v]" -map "[a]" -vcodec libx264 -pix_fmt yuv420p -r 30 -g 60 -b:v 2500k \
-acodec libmp3lame -b:a 128k -ar 44100 -preset ultrafast tap2.mp4
Se você precisar voltar a colocar a imagem na altura original, use
ffmpeg -loop 1 -i hinh1.jpg -i 2.mp4 \
-filter_complex "[1]scale=iw/2.5:-1[ovrl]; \
[0]crop=in_w:in_h-360,pad=iw:ih+360:0:180[bg]; \
[bg][ovrl]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[v],\
[1]pan=stereo|c0<c0+0*c1|c1<c0+0*c1,aeval=val(0)|-val(1)[a]" \
-map "[v]" -map "[a]" -vcodec libx264 -pix_fmt yuv420p -r 30 -g 60 -b:v 2500k \
-acodec libmp3lame -b:a 128k -ar 44100 -preset ultrafast tap2.mp4