ffmpeg -i /storage/emulated/0/videomixer/1507106526128.mp4 -i /storage/emulated/0/videomixer/1507106535260.mp4 -i /storage/emulated/0/videomixer/watermark.jpg -c:v libx264 -preset ultrafast -crf 22 -filter_complex [0:v0][1:v1]concat=n=2:v=1 [v];[0:v] [1:v] overlay=10:main_h-overlay_h-10 -map [v] /storage/emulated/0/videomixer/1507106541979.mp4