[FFmpeg-user] drawbox: text subpixel rendering (expected result)

[Nikita Zlobin]

For comparison, how could it look with RGB for libfreetype subpixel
layout: https://imgur.com/vFxavmR.png

Command:

stdbuf -o0 yes | SDL_AUDIODRIVER=alsa \
ffplay -v info -f rawvideo -pixel_format gray -video_size 1x1 -codec:v
rawvideo -framerate 20000 \ -vf "
    nullsink, nullsrc = $((128*3))x$((32*3)), scale = flags = bicubic,
format = gray, drawtext = text=Example : x=9 : y=9 : font=serif :
fontsize=14*3 : fontcolor=white, scale = 0:32:flags=bicubic, rgbashift
= rh=1:bh=-1, scale = 128:0:flags=area " -