ffmpeg -f v4l2 -video_size 1280x720 -framerate 30 -vcodec mjpeg -i /dev/v4l/by-id/usb-046d_HD_Pro_Webcam_C920_82A3901F-video-index0 -f v4l2 -video_size 1280x720 -framerate 60.0002 -vcodec mjpeg -i /dev/v4l/by-id/usb-HD_Camera_Manufacturer_USB_2.0_Camera-video-index0 -preset ultrafast -threads 0 -filter_complex "color=black:2560x60[b], [0:v][1:v]hstack[t], [t][b]vstack, drawtext=fontfile=UbuntuMono-R.ttf: textfile=send.txt: reload=1: x=10: y=740: fontsize=40: fontcolor=white, drawtext=fontfile=UbuntuMono-R.ttf: text=%{n}: x=w-tw-10: y=h-th-10: fontsize=40: fontcolor=white" -r 30 dualwtext.ts