绘制文本

drawtext 滤镜

ffplay -f lavfi -i testsrc -vf "drawtext=fontfile=站酷庆科黄油体.ttf:text='Hello world!':fontsize=32:fontcolor=red:bordercolor=green:borderw=5:x=(sin(t)+1)*w/2:y=(cos(t)+1)*h/2"

ffmpeg -i mandelbrot.mp4 -vf "drawtext=fontfile=站酷庆科黄油体.ttf:text='Hello world!':fontsize=64:fontcolor=red:bordercolor=green:borderw=5" mandelbrot-drawtext.mp4